TY - JOUR T1 - Metagenome sequencing-based strain-level and functional characterization of supragingival microbiome associated with dental caries in children JF - Journal of Oral Microbiology Y1 - 2019 A1 - Al-Hebshi, Nezar Noor A1 - Baraniya, Divyashri A1 - Chen, Tsute A1 - Hill, Jennifer A1 - Puri, Sumant A1 - Tellez, Marisol A1 - Hassan, Nur A. A1 - Rita R Colwell A1 - Ismail, Amid AB - Studies of the microbiome associated with dental caries have largely relied on 16S rRNA sequence analysis, which is associated with PCR biases, low taxonomic resolution, and inability to accurately study functions. Here, we employed whole metagenome shotgun sequencing, coupled with high-resolution analysis algorithm, to analyze supragingival microbiomes from 30 children with or without dental caries. A total of 726 bacterial strains belonging to 406 species, in addition to 34 bacteriophages were identified. A core bacteriome was identified at the species and strain levels. Species of Prevotella, Veillonella, as yet unnamed Actinomyces, and Atopobium showed strongest association with caries; Streptococcus sp. AS14 and Leptotrichia sp. Oral taxon 225, among others, were overabundant in caries-free. For several species, the association was strain-specific. Furthermore, for some species, e.g. Streptococcus mitis and Streptococcus sanguinis, sister strains showed differential associations. Noteworthy, associations were also identified for phages: Streptococcus phage M102 with caries and Haemophilus phage HP1 with caries-free. Functionally, potentially relevant features were identified including urate, vitamin K2, and polyamine biosynthesis in association with caries; and three deiminases and lactate dehydrogenase with health. The results demonstrate new associations between the microbiome and dental caries at the strain and functional levels that need further investigation. UR - https://www.tandfonline.com/doi/full/10.1080/20002297.2018.1557986 CP - 118 J1 - Journal of Oral Microbiology M3 - 10.1080/20002297.2018.1557986 ER - TY - JOUR T1 - Quantum Capacitance-Limited MoS2 Biosensors Enable Remote Label-Free Enzyme Measurements JF - Nanoscale Y1 - 2019 A1 - Le, Son T A1 - Guros, Nicholas B A1 - Bruce, Robert C A1 - Cardone, Antonio A1 - Amin, Niranjana D A1 - Zhang, Siyuan A1 - Klauda, Jeffery A1 - Pant, Harish C A1 - Richter, Curt A A1 - Balijepalli, Arvind UR - http://pubs.rsc.org/en/Content/ArticleLanding/2019/NR/C9NR03171Ehttp://pubs.rsc.org/en/content/articlepdf/2019/NR/C9NR03171E J1 - Nanoscale M3 - 10.1039/C9NR03171E ER - TY - JOUR T1 - Biofilms Comprise a Component of the Annual Cycle of Vibrio cholerae in the Bay of Bengal Estuary JF - mBio Y1 - 2018 A1 - Sultana, Marzia A1 - Nusrin, Suraia A1 - Hasan, Nur A. A1 - Sadique, Abdus A1 - Ahmed, Kabir U. A1 - Islam, Atiqul A1 - Hossain, Anwar A1 - Longini, Ira A1 - Nizam, Azhar A1 - Huq, Anwar A1 - Siddique, Abul K. A1 - Sack, David A. A1 - Sack, Richard B. A1 - Rita R Colwell A1 - Alam, Munirul ED - Vidaver, Anne K. AB - Vibrio cholerae, an estuarine bacterium, is the causative agent of cholera, a severe diarrheal disease that demonstrates seasonal incidence in Bangladesh. In an extensive study of V. cholerae occurrence in a natural aquatic environment, water and plankton samples were collected biweekly between December 2005 and November 2006 from Mathbaria, an estuarine village of Bangladesh near the mangrove forests of the Sundarbans. Toxigenic V. cholerae exhibited two seasonal growth peaks, one in spring (March to May) and another in autumn (September to November), corresponding to the two annual seasonal outbreaks of cholera in this region. The total numbers of bacteria determined by heterotrophic plate count (HPC), representing culturable bacteria, accounted for 1% to 2.7% of the total numbers obtained using acridine orange direct counting (AODC). The highest bacterial culture counts, including toxigenic V. cholerae, were recorded in the spring. The direct fluorescent antibody (DFA) assay was used to detect V. cholerae O1 cells throughout the year, as free-living cells, within clusters, or in association with plankton. V. cholerae O1 varied significantly in morphology, appearing as distinctly rod-shaped cells in the spring months, while small coccoid cells within thick clusters of biofilm were observed during interepidemic periods of the year, notably during the winter months. Toxigenic V. cholerae O1 was culturable in natural water during the spring when the temperature rose sharply. The results of this study confirmed biofilms to be a means of persistence for bacteria and an integral component of the annual life cycle of toxigenic V. cholerae in the estuarine environment of Bangladesh. UR - https://mbio.asm.org/content/9/2/e00483-18 CP - 2 J1 - mBio M3 - 10.1128/mBio.00483-18 ER - TY - JOUR T1 - Environmental and hydroclimatic factors influencing Vibrio populations in the estuarine zone of the Bengal delta JF - Environmental Monitoring and Assessment Y1 - 2018 A1 - Neogi, Sucharit A1 - Rubin, Lara A1 - Alam, Munirul A1 - Harder, Jens A1 - Yamasaki, Shinji A1 - Rita R Colwell AB - The objective of this study was to determine environmental parameters driving Vibrio populations in the estuarine zone of the Bengal delta. Spatio-temporal data were collected at river estuary, mangrove, beach, pond, and canal sites. Effects of salinity, tidal amplitude, and a cyclone and tsunami were included in the study. Vibrio population shifts were found to be correlated with tide-driven salinity and suspended particulate matter (SPM). Increased abundance of Vibrio spp. in surface water was observed after a cyclone, attributed to re-suspension of benthic particulate organic carbon (POC), and increased availability of chitin and dissolved organic carbon (DOC). Approximately a two log10 increase in the (p < 0.05) number of Vibrio spp. was observed in < 20 μm particulates, compared with microphytoplankton (20–60 μm) and zooplankton > 60 μm fractions. Benthic and suspended sediment comprised a major reservoir of Vibrio spp. Results of microcosm experiments showed enhanced growth of vibrios was related to concentration of organic matter in SPM. It is concluded that SPM, POC, chitin, and salinity significantly influence abundance and distribution of vibrios in the Bengal delta estuarine zone. Keywords Vibrio Salinity Cyclone Tide Chitin Sediment dynamics UR - https://link.springer.com/article/10.1007%2Fs10661-018-6925-7 CP - 10 J1 - Environ Monit Assess M3 - 10.1007/s10661-018-6925-7 ER - TY - JOUR T1 - A Metagenomic Approach to Evaluating Surface Water Quality in Haiti JF - International Journal of Environmental Research and Public Health Y1 - 2018 A1 - Roy, Monika A1 - Arnaud, Jean A1 - Jasmin, Paul A1 - Hamner, Steve A1 - Hasan, Nur A1 - Rita R Colwell A1 - Ford, Timothy AB - The cholera epidemic that occurred in Haiti post-earthquake in 2010 has resulted in over 9000 deaths during the past eight years. Currently, morbidity and mortality rates for cholera have declined, but cholera cases still occur on a daily basis. One continuing issue is an inability to accurately predict and identify when cholera outbreaks might occur. To explore this surveillance gap, a metagenomic approach employing environmental samples was taken. In this study, surface water samples were collected at two time points from several sites near the original epicenter of the cholera outbreak in the Central Plateau of Haiti. These samples underwent whole genome sequencing and subsequent metagenomic analysis to characterize the microbial community of bacteria, fungi, protists, and viruses, and to identify antibiotic resistance and virulence associated genes. Replicates from sites were analyzed by principle components analysis, and distinct genomic profiles were obtained for each site. Cholera toxin converting phage was detected at one site, and Shiga toxin converting phages at several sites. Members of the Acinetobacter family were frequently detected in samples, including members implicated in waterborne diseases. These results indicate a metagenomic approach to evaluating water samples can be useful for source tracking and the surveillance of pathogens such as Vibrio cholerae over time, as well as for monitoring virulence factors such as cholera toxin. VL - 1542 UR - https://www.ncbi.nlm.nih.gov/pubmed/30309013 CP - 10 J1 - IJERPH ER - TY - JOUR T1 - Satellites and Cell Phones Form a Cholera Early-Warning System JF - Eos Y1 - 2018 A1 - Akanda, Ali A1 - Aziz, Sonia A1 - Jutla, Antarpreet A1 - Huq, Anwar A1 - Alam, Munirul A1 - Ahsan, Gias A1 - Rita R Colwell VL - 99 UR - https://eos.org/project-updates/satellites-and-cell-phones-form-a-cholera-early-warning-system J1 - Eos M3 - 10.1029/2018EO094839 ER - TY - JOUR T1 - Virulence-Related Genes Identified from the Genome Sequence of the Non-O1/Non-O139 Vibrio cholerae Strain VcN1, Isolated from Dhaka, Bangladesh JF - Genome Announcements Y1 - 2018 A1 - Hossain, Maqsud A1 - Alam, Munirul A1 - Khaleque, Abdul A1 - Islam, Sohidul A1 - Sadique, Abdus A1 - Khan, Nayeim A1 - Halim, Zahra A1 - Sarker, Mrinmoy A1 - El-Sayed, Najib M. A1 - Huq, Anwar A1 - Ahsan, Gias Uddin A1 - Rita R Colwell AB - We report here the first draft genome sequence of the non-O1/non-O139 Vibrio cholerae strain VcN1, isolated from Dhaka, Bangladesh. The data submitted to GenBank for this strain will contribute to advancing our understanding of this environmentally disseminated bacterium, including its virulence and its evolution as an important pathogen. UR - https://mra.asm.org/content/6/10/e01513-17 CP - 10 J1 - Genome Announc M3 - 10.1128/genomeA.01513-17 ER - TY - JOUR T1 - Assessment of Risk of Cholera in Haiti following Hurricane Matthew JF - The American Journal of Tropical Medicine and Hygiene Y1 - 2017 A1 - Huq, Anwar A1 - Anwar, Rifat A1 - Rita R Colwell A1 - McDonald, Michael D. A1 - Khan, Rakib A1 - Jutla, Antarpreet A1 - Akanda, Shafqat AB - Damage to the inferior and fragile water and sanitation infrastructure of Haiti after Hurricane Matthew has created an urgent public health emergency in terms of likelihood of cholera occurring in the human population. Using satellite-derived data on precipitation, gridded air temperature, and hurricane path and with information on water and sanitation (WASH) infrastructure, we tracked changing environmental conditions conducive for growth of pathogenic vibrios. Based on these data, we predicted and validated the likelihood of cholera cases occurring past hurricane. The risk of cholera in the southwestern part of Haiti remained relatively high since November 2016 to the present. Findings of this study provide a contemporary process for monitoring ground conditions that can guide public health intervention to control cholera in human population by providing access to vaccines, safe WASH facilities. Assuming current social and behavioral patterns remain constant, it is recommended that WASH infrastructure should be improved and considered a priority especially before 2017 rainy season. VL - 97 UR - http://www.ajtmh.org/content/journals/10.4269/ajtmh.17-0048 CP - 3 M3 - 10.4269/ajtmh.17-0048 ER - TY - JOUR T1 - Comparative Genomics of Escherichia coli Isolated from Skin and Soft Tissue and Other Extraintestinal Infections JF - mBio Y1 - 2017 A1 - Ranjan, Amit A1 - Shaik, Sabiha A1 - Nandanwar, Nishant A1 - Hussain, Arif A1 - Tiwari, Sumeet K. A1 - Semmler, Torsten A1 - Jadhav, Savita A1 - Wieler, Lothar H. A1 - Alam, Munirul A1 - Rita R Colwell A1 - Ahmed, Niyaz ED - Cossart, Pascale F. AB - Escherichia coli, an intestinal Gram-negative bacterium, has been shown to be associated with a variety of diseases in addition to intestinal infections, such as urinary tract infections (UTIs), meningitis in neonates, septicemia, skin and soft tissue infections (SSTIs), and colisepticemia. Thus, for nonintestinal infections, it is categorized as extraintestinal pathogenic E. coli (ExPEC). It is also an opportunistic pathogen, causing cross infections, notably as an agent of zoonotic diseases. However, comparative genomic data providing functional and genetic coordinates for ExPEC strains associated with these different types of infections have not proven conclusive. In the study reported here, ExPEC E. coli isolated from SSTIs was characterized, including virulence and drug resistance profiles, and compared with isolates from patients suffering either pyelonephritis or septicemia. Results revealed that the majority of the isolates belonged to two pathogenic phylogroups, B2 and D. Approximately 67% of the isolates were multidrug resistant (MDR), with 85% producing extended-spectrum beta-lactamase (ESBL) and 6% producing metallo-beta-lactamase (MBL). The blaCTX-M-15 genotype was observed in at least 70% of the E. coli isolates in each category, conferring resistance to an extended range of beta-lactam antibiotics. Whole-genome sequencing and comparative genomics of the ExPEC isolates revealed that two of the four isolates from SSTIs, NA633 and NA643, belong to pandemic sequence type ST131, whereas functional characteristics of three of the ExPEC pathotypes revealed that they had equal capabilities to form biofilm and were resistant to human serum. Overall, the isolates from a variety of ExPEC infections demonstrated similar resistomes and virulomes and did not display any disease-specific functional or genetic coordinates. IMPORTANCE Infections caused by extraintestinal pathogenic E. coli (ExPEC) are of global concern as they result in significant costs to health care facilities management. The recent emergence of a multidrug-resistant pandemic clone, Escherichia coli ST131, is of primary concern as a global threat. In developing countries, such as India, skin and soft tissue infections (SSTIs) associated with E. coli are marginally addressed. In this study, we employed both genomic analysis and phenotypic assays to determine relationships, if any, among the ExPEC pathotypes. Similarity between antibiotic resistance and virulence profiles was observed, ST131 isolates from SSTIs were reported, and genomic similarities among strains isolated from different disease conditions were detected. This study provides functional molecular infection epidemiology insight into SSTI-associated E. coli compared with ExPEC pathotypes. UR - http://mbio.asm.org/lookup/doi/10.1128/mBio.01070-17 CP - 4 J1 - mBio M3 - 10.1128/mBio.01070-17 ER - TY - JOUR T1 - Comprehensive benchmarking and ensemble approaches for metagenomic classifiers JF - Genome Biology Y1 - 2017 A1 - McIntyre, Alexa B. R. A1 - Ounit, Rachid A1 - Afshinnekoo, Ebrahim A1 - Prill, Robert J. A1 - Hénaff, Elizabeth A1 - Alexander, Noah A1 - Minot, Samuel S. A1 - Danko, David A1 - Foox, Jonathan A1 - Ahsanuddin, Sofia A1 - Tighe, Scott A1 - Hasan, Nur A. A1 - Subramanian, Poorani A1 - Moffat, Kelly A1 - Levy, Shawn A1 - Lonardi, Stefano A1 - Greenfield, Nick A1 - Rita R Colwell A1 - Rosen, Gail L. A1 - Mason, Christopher E. UR - http://genomebiology.biomedcentral.com/articles/10.1186/s13059-017-1299-7 CP - 1210 J1 - Genome Biol M3 - 10.1186/s13059-017-1299-7 ER - TY - JOUR T1 - Genomic Methods and Microbiological Technologies for Profiling Novel and Extreme Environments for the Extreme Microbiome Project (XMP) JF - Journal of Biomolecular Techniques : JBT Y1 - 2017 A1 - Tighe, Scott A1 - Afshinnekoo, Ebrahim A1 - Rock, Tara M. A1 - McGrath, Ken A1 - Alexander, Noah A1 - McIntyre, Alexa A1 - Ahsanuddin, Sofia A1 - Bezdan, Daniela A1 - Green, Stefan J. A1 - Joye, Samantha A1 - Stewart Johnson, Sarah A1 - Baldwin, Don A. A1 - Bivens, Nathan A1 - Ajami, Nadim A1 - Carmical, Joseph R. A1 - Herriott, Ian Charold A1 - Rita R Colwell A1 - Donia, Mohamed A1 - Foox, Jonathan A1 - Greenfield, Nick A1 - Hunter, Tim A1 - Hoffman, Jessica A1 - Hyman, Joshua A1 - Jorgensen, Ellen A1 - Krawczyk, Diana A1 - Lee, Jodie A1 - Levy, Shawn A1 - Garcia-Reyero, àlia A1 - Settles, Matthew A1 - Thomas, Kelley A1 - ómez, Felipe A1 - Schriml, Lynn A1 - Kyrpides, Nikos A1 - Zaikova, Elena A1 - Penterman, Jon A1 - Mason, Christopher E. AB - The Extreme Microbiome Project (XMP) is a project launched by the Association of Biomolecular Resource Facilities Metagenomics Research Group (ABRF MGRG) that focuses on whole genome shotgun sequencing of extreme and unique environments using a wide variety of biomolecular techniques. The goals are multifaceted, including development and refinement of new techniques for the following: 1) the detection and characterization of novel microbes, 2) the evaluation of nucleic acid techniques for extremophilic samples, and 3) the identification and implementation of the appropriate bioinformatics pipelines. Here, we highlight the different ongoing projects that we have been working on, as well as details on the various methods we use to characterize the microbiome and metagenome of these complex samples. In particular, we present data of a novel multienzyme extraction protocol that we developed, called Polyzyme or MetaPolyZyme. Presently, the XMP is characterizing sample sites around the world with the intent of discovering new species, genes, and gene clusters. Once a project site is complete, the resulting data will be publically available. Sites include Lake Hillier in Western Australia, the “Door to Hell” crater in Turkmenistan, deep ocean brine lakes of the Gulf of Mexico, deep ocean sediments from Greenland, permafrost tunnels in Alaska, ancient microbial biofilms from Antarctica, Blue Lagoon Iceland, Ethiopian toxic hot springs, and the acidic hypersaline ponds in Western Australia. VL - 28 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5345951/ CP - 1 J1 - J Biomol Tech M3 - 10.7171/jbt.17-2801-004 ER - TY - JOUR T1 - Hydroclimatic sustainability assessment of changing climate on cholera in the Ganges-Brahmaputra basin JF - Advances in Water Resources Y1 - 2017 A1 - Nasr-Azadani, Fariborz A1 - Khan, Rakibul A1 - Rahimikollu, Javad A1 - Unnikrishnan, Avinash A1 - Akanda, Ali A1 - Alam, Munirul A1 - Huq, Anwar A1 - Jutla, Antarpreet A1 - Rita R Colwell AB - The association of cholera and climate has been extensively documented. However, determining the effects of changing climate on the occurrence of disease remains a challenge. Bimodal peaks of cholera in Bengal Delta are hypothesized to be linked to asymmetric flow of the Ganges and Brahmaputra rivers. Spring cholera is related to intrusion of bacteria-laden coastal seawater during low flow seasons, while autumn cholera results from cross-contamination of water resources when high flows in the rivers cause massive inundation. Coarse resolution of General Circulation Model (GCM) output (usually at 100 – 300 km)cannot be used to evaluate variability at the local scale(10–20 km),hence the goal of this study was to develop a framework that could be used to understand impacts of climate change on occurrence of cholera. Instead of a traditional approach of downscaling precipitation, streamflow of the two rivers was directly linked to GCM outputs, achieving reasonable accuracy (R2 = 0.89 for the Ganges and R2 = 0.91 for the Brahmaputra)using machine learning algorithms (Support Vector Regression-Particle Swarm Optimization). Copula methods were used to determine probabilistic risks of cholera under several discharge conditions. Key results, using model outputs from ECHAM5, GFDL, andHadCM3for A1B and A2 scenarios, suggest that the combined low flow of the two rivers may increase in the future, with high flows increasing for first half of this century, decreasing thereafter. Spring and autumn cholera, assuming societal conditions remain constant e.g., at the current rate, may decrease. However significant shifts were noted in the magnitude of river discharge suggesting that cholera dynamics of the delta may well demonstrate an uncertain predictable pattern of occurrence over the next century. VL - 108 UR - https://linkinghub.elsevier.com/retrieve/pii/S030917081630728X J1 - Advances in Water Resources M3 - 10.1016/j.advwatres.2016.11.018 ER - TY - JOUR T1 - Vibrio cholerae O1 with Reduced Susceptibility to Ciprofloxacin and Azithromycin Isolated from a Rural Coastal Area of Bangladesh JF - Frontiers in Microbiology Y1 - 2017 A1 - Rashed, Shah M. A1 - Hasan, Nur A. A1 - Alam, Munirul A1 - Sadique, Abdus A1 - Sultana, Marzia A1 - Hoq, Md. Mozammel A1 - Sack, R. Bradley A1 - Rita R Colwell A1 - Huq, Anwar AB - Cholera outbreaks occur each year in the remote coastal areas of Bangladesh and epidemiological surveillance and routine monitoring of cholera in these areas is challenging. In this study, a total of 97 Vibrio cholerae O1 isolates from Mathbaria, Bangladesh, collected during 2010 and 2014 were analyzed for phenotypic and genotypic traits, including antimicrobial susceptibility. Of the 97 isolates, 95 possessed CTX-phage mediated genes, ctxA, ace, and zot, and two lacked the cholera toxin gene, ctxA. Also both CTX+ and CTX− V. cholerae O1 isolated in this study carried rtxC, tcpAET, and hlyA. The classical cholera toxin gene, ctxB1, was detected in 87 isolates, while eight had ctxB7. Of 95 CTX+ V. cholerae O1, 90 contained rstRET and 5 had rstRCL. All isolates, except two, contained SXT related integrase intSXT. Resistance to penicillin, streptomycin, nalidixic acid, sulfamethoxazole-trimethoprim, erythromycin, and tetracycline varied between the years of study period. Most importantly, 93% of the V. cholerae O1 were multidrug resistant. Six different resistance profiles were observed, with resistance to streptomycin, nalidixic acid, tetracycline, and sulfamethoxazole-trimethoprim predominant every year. Ciprofloxacin and azithromycin MIC were 0.003–0.75 and 0.19–2.00 μg/ml, respectively, indicating reduced susceptibility to these antibiotics. Sixteen of the V. cholerae O1 isolates showed higher MIC for azithromycin (≥0.5 μg/ml) and were further examined for 10 macrolide resistance genes, erm(A), erm(B), erm(C), ere(A), ere(B), mph(A), mph(B), mph(D), mef(A), and msr(A) with none testing positive for the macrolide resistance genes. UR - http://journal.frontiersin.org/article/10.3389/fmicb.2017.00252 J1 - Front. Microbiol. M3 - 10.3389/fmicb.2017.00252 ER - TY - JOUR T1 - The microbiomes of blowflies and houseflies as bacterial transmission reservoirs JF - Scientific Reports Y1 - 2017 A1 - Junqueira, AC A1 - Ratan, Aakrosh A1 - Acerbi, Enzo A1 - Drautz-Moses, Daniela I. A1 - Premkrishnan, BNV A1 - Costea, PI A1 - Linz, Bodo A1 - Purbojati, Rikky W. A1 - Paulo, Daniel F. A1 - Gaultier, Nicolas E. A1 - Subramanian, Poorani A1 - Hasan, Nur A. A1 - Rita R Colwell A1 - Bork, Peer A1 - Azeredo-Espin, Ana Maria L. A1 - Bryant, Donald A. A1 - Schuster, Stephan C. AB - Blowflies and houseflies are mechanical vectors inhabiting synanthropic environments around the world. They feed and breed in fecal and decaying organic matter, but the microbiome they harbour and transport is largely uncharacterized. We sampled 116 individual houseflies and blowflies from varying habitats on three continents and subjected them to high-coverage, whole-genome shotgun sequencing. This allowed for genomic and metagenomic analyses of the host-associated microbiome at the species level. Both fly host species segregate based on principal coordinate analysis of their microbial communities, but they also show an overlapping core microbiome. Legs and wings displayed the largest microbial diversity and were shown to be an important route for microbial dispersion. The environmental sequencing approach presented here detected a stochastic distribution of human pathogens, such as Helicobacter pylori, thereby demonstrating the potential of flies as proxies for environmental and public health surveillance. UR - http://www.nature.com/articles/s41598-017-16353-x CP - 1 J1 - Sci Rep M3 - 10.1038/s41598-017-16353-x ER - TY - JOUR T1 - Comparison of inferred relatedness based on multilocus variable-number tandem-repeat analysis and whole genome sequencing of Vibrio cholerae O1 JF - FEMS Microbiology Letters Y1 - 2016 A1 - Rashid, Mahamud-ur A1 - Almeida, Mathieu A1 - Azman, Andrew S. A1 - Lindsay, Brianna R. A1 - Sack, David A. A1 - Rita R Colwell A1 - Huq, Anwar A1 - Morris, J. Glenn A1 - Alam, Munirul A1 - Stine, O. Colin ED - Winstanley, Craig AB - Vibrio cholerae causes cholera, a severe diarrheal disease. Understanding the local genetic diversity and transmission of V. cholerae will improve our ability to control cholera. Vibrio cholerae isolates clustered in genetically related groups (clonal complexes, CC) by multilocus variable tandem-repeat analysis (MLVA) were compared by whole genome sequencing (WGS). Isolates in CC1 had been isolated from two geographical locations. Isolates in a second genetically distinct group, CC2, were isolated only at one location. Using WGS, CC1 isolates from both locations revealed, on average, 43.8 nucleotide differences, while those strains comprising CC2 averaged 19.7 differences. Strains from both MLVA-CCs had an average difference of 106.6. Thus, isolates comprising CC1 were more closely related (P < 10−6) to each other than to isolates in CC2. Within a MLVA-CC, after removing all paralogs, alternative alleles were found in all possible combinations on separate chromosomes indicative of recombination within the core genome. Including recombination did not affect the distinctiveness of the MLVA-CCs when measured by WGS. We found that WGS generally reflected the same genetic relatedness of isolates as MLVA, indicating that isolates from the same MLVA-CC shared a more recent common ancestor than isolates from the same location that clustered in a distinct MLVA-CC. VL - 36389 UR - https://academic.oup.com/femsle/article-lookup/doi/10.1093/femsle/fnw116 CP - 12 J1 - FEMS Microbiology Letters M3 - 10.1093/femsle/fnw116 ER - TY - JOUR T1 - Cross-talk among flesh-eating Aeromonas hydrophila strains in mixed infection leading to necrotizing fasciitis JF - Proceedings of the National Academy of Sciences Y1 - 2016 A1 - Ponnusamy, Duraisamy A1 - Kozlova, Elena V. A1 - Sha, Jian A1 - Erova, Tatiana E. A1 - Azar, Sasha R. A1 - Fitts, Eric C. A1 - Kirtley, Michelle L. A1 - Tiner, Bethany L. A1 - Andersson, Jourdan A. A1 - Grim, Christopher J. A1 - Isom, Richard P. A1 - Hasan, Nur A. A1 - Rita R Colwell A1 - Chopra, Ashok K. AB - Necrotizing fasciitis (NF) caused by flesh-eating bacteria is associated with high case fatality. In an earlier study, we reported infection of an immunocompetent individual with multiple strains of Aeromonas hydrophila (NF1–NF4), the latter three constituted a clonal group whereas NF1 was phylogenetically distinct. To understand the complex interactions of these strains in NF pathophysiology, a mouse model was used, whereby either single or mixed A. hydrophila strains were injected intramuscularly. NF2, which harbors exotoxin A (exoA) gene, was highly virulent when injected alone, but its virulence was attenuated in the presence of NF1 (exoA-minus). NF1 alone, although not lethal to animals, became highly virulent when combined with NF2, its virulence augmented by cis-exoA expression when injected alone in mice. Based on metagenomics and microbiological analyses, it was found that, in mixed infection, NF1 selectively disseminated to mouse peripheral organs, whereas the other strains (NF2, NF3, and NF4) were confined to the injection site and eventually cleared. In vitro studies showed NF2 to be more effectively phagocytized and killed by macrophages than NF1. NF1 inhibited growth of NF2 on solid media, but ExoA of NF2 augmented virulence of NF1 and the presence of NF1 facilitated clearance of NF2 from animals either by enhanced priming of host immune system or direct killing via a contact-dependent mechanism. VL - 11312161268 UR - http://www.pnas.org/lookup/doi/10.1073/pnas.1523817113 CP - 3321029 J1 - Proc Natl Acad Sci USA M3 - 10.1073/pnas.1523817113 ER - TY - JOUR T1 - Enrichment dynamics of Listeria monocytogenes and the associated microbiome from naturally contaminated ice cream linked to a listeriosis outbreak JF - BMC Microbiology Y1 - 2016 A1 - Ottesen, Andrea A1 - Ramachandran, Padmini A1 - Reed, Elizabeth A1 - White, James R. A1 - Hasan, Nur A1 - Subramanian, Poorani A1 - Ryan, Gina A1 - Jarvis, Karen A1 - Grim, Christopher A1 - Daquiqan, Ninalynn A1 - Hanes, Darcy A1 - Allard, Marc A1 - Rita R Colwell A1 - Brown, Eric A1 - Chen, Yi UR - http://bmcmicrobiol.biomedcentral.com/articles/10.1186/s12866-016-0894-1 J1 - BMC Microbiol M3 - 10.1186/s12866-016-0894-1 ER - TY - JOUR T1 - Modeling Sustainability: Population, Inequality, Consumption, and Bidirectional Coupling of the Earth and Human Systems JF - National Science Review Y1 - 2016 A1 - Motesharrei, Safa A1 - Rivas, Jorge A1 - Kalnay, Eugenia A1 - Asrar, Ghassem R. A1 - Busalacchi, Antonio J. A1 - Cahalan, Robert F. A1 - Cane, Mark A. A1 - Rita R Colwell A1 - Feng, Kuishuang A1 - Franklin, Rachel S. A1 - Hubacek, Klaus A1 - Miralles-Wilhelm, Fernando A1 - Miyoshi, Takemasa A1 - Ruth, Matthias A1 - Sagdeev, Roald A1 - Shirmohammadi, Adel A1 - Shukla, Jagadish A1 - Srebric, Jelena A1 - Yakovenko, Victor M. A1 - Zeng, Ning AB - Over the last two centuries, the impact of the Human System has grown dramatically, becoming strongly dominant within the Earth System in many different ways. Consumption, inequality, and population have increased extremely fast, especially since about 1950, threatening to overwhelm the many critical functions and ecosystems of the Earth System. Changes in the Earth System, in turn, have important feedback effects on the Human System, with costly and potentially serious consequences. However, current models do not incorporate these critical feedbacks. We argue that in order to understand the dynamics of either system, Earth System Models must be coupled with Human System Models through bidirectional couplings representing the positive, negative, and delayed feedbacks that exist in the real systems. In particular, key Human System variables, such as demographics, inequality, economic growth, and migration, are not coupled with the Earth System but are instead driven by exogenous estimates, such as United Nations population projections. This makes current models likely to miss important feedbacks in the real Earth–Human system, especially those that may result in unexpected or counterintuitive outcomes, and thus requiring different policy interventions from current models. The importance and imminence of sustainability challenges, the dominant role of the Human System in the Earth System, and the essential roles the Earth System plays for the Human System, all call for collaboration of natural scientists, social scientists, and engineers in multidisciplinary research and modeling to develop coupled Earth–Human system models for devising effective science-based policies and measures to benefit current and future generations. UR - https://academic.oup.com/nsr/article-lookup/doi/10.1093/nsr/nww081 J1 - Nat. Sci. Rev. M3 - 10.1093/nsr/nww081 ER - TY - JOUR T1 - Phylogenetic Diversity of Vibrio cholerae Associated with Endemic Cholera in Mexico from 1991 to 2008 JF - mBio Y1 - 2016 A1 - Choi, Seon Y A1 - Rashed, Shah M. A1 - Hasan, Nur A. A1 - Alam, Munirul A1 - Islam, Tarequl A1 - Sadique, Abdus A1 - Johura, Fatema-Tuz A1 - Eppinger, Mark A1 - Ravel, Jacques A1 - Huq, Anwar A1 - Cravioto, Alejandro A1 - Rita R Colwell AB - An outbreak of cholera occurred in 1991 in Mexico, where it had not been reported for more than a century and is now endemic. Vibrio cholerae O1 prototype El Tor and classical strains coexist with altered El Tor strains (1991 to 1997). Nontoxigenic (CTX−) V. cholerae El Tor dominated toxigenic (CTX+) strains (2001 to 2003), but V. cholerae CTX+ variant El Tor was isolated during 2004 to 2008, outcompeting CTX− V. cholerae. Genomes of six Mexican V. cholerae O1 strains isolated during 1991 to 2008 were sequenced and compared with both contemporary and archived strains of V. cholerae. Three were CTX+ El Tor, two were CTX− El Tor, and the remaining strain was a CTX+ classical isolate. Whole-genome sequence analysis showed the six isolates belonged to five distinct phylogenetic clades. One CTX− isolate is ancestral to the 6th and 7th pandemic CTX+ V. cholerae isolates. The other CTX− isolate joined with CTX− non-O1/O139 isolates from Haiti and seroconverted O1 isolates from Brazil and Amazonia. One CTX+ isolate was phylogenetically placed with the sixth pandemic classical clade and the V. cholerae O395 classical reference strain. Two CTX+ El Tor isolates possessing intact Vibrio seventh pandemic island II (VSP-II) are related to hybrid El Tor isolates from Mozambique and Bangladesh. The third CTX+ El Tor isolate contained West African-South American (WASA) recombination in VSP-II and showed relatedness to isolates from Peru and Brazil. Except for one isolate, all Mexican isolates lack SXT/R391 integrative conjugative elements (ICEs) and sensitivity to selected antibiotics, with one isolate resistant to streptomycin. No isolates were related to contemporary isolates from Asia, Africa, or Haiti, indicating phylogenetic diversity. VL - 7 UR - http://mbio.asm.org/lookup/doi/10.1128/mBio.02160-15 CP - 2 J1 - mBio M3 - 10.1128/mBio.02160-15 ER - TY - JOUR T1 - Reduced Susceptibility to Extended-Spectrum β-Lactams in Vibrio cholerae Isolated in Bangladesh JF - Frontiers in Public Health Y1 - 2016 A1 - Ceccarelli, Daniela A1 - Alam, Munirul A1 - Huq, Anwar A1 - Rita R Colwell UR - http://journal.frontiersin.org/article/10.3389/fpubh.2016.00231/full J1 - Front. Public Health M3 - 10.3389/fpubh.2016.00231 ER - TY - JOUR T1 - Downscaling river discharge to assess the effects of climate change on cholera outbreaks in the Bengal Delta JF - Climate Research Y1 - 2015 A1 - Nasr-Azadani, F A1 - Unnikrishnan, A A1 - Akanda, A A1 - Islam, S A1 - Alam, M A1 - Huq, A A1 - Jutla, A A1 - Rita R Colwell AB - Endemic cholera in the Bengal Delta region of South Asia has been associated with asymmetric and episodic variability of river discharge. Spring cholera was found to be related to intrusion of bacteria-laden coastal seawater during low flow seasons. Autumn cholera was hypothesized to result from cross-contamination of water resources when high river discharge causes massive inland inundation. The effect of climate change on diarrheal diseases has not been explored, because of the difficulties in establishing linkages between coarse-resolution global climate model outputs with localized disease outbreaks. Since rivers act as corridors for transport of cholera bacteria, the first step is to understand the discharge variability that may occur with climate change and whether it is linked to cholera. Here, we present a framework for downscaling precipitation from global climate models for river discharge in the Ganges-Brahmaputra-Meghna basin. Using a data-mining method that includes particle swarm optimization-based support vector regression, precipitation was downscaled for a statistical multiple regressive model to estimate river discharge in the basin. Key results from an ensemble of HadCM3, GFDL, and ECHAM5 models indicated 8 and 7.5% increase in flows for the IPCC A1B and A2 scenarios, respectively. The majority of the changes are attributable to increases in flows from February through August for both scenarios, with little to no change in seasonality of high and low flows during the next century. The probability of spring and autumn cholera is likely to increase steadily in the endemic region of the Bengal Delta. VL - 64 UR - http://www.int-res.com/abstracts/cr/v64/n3/p257-274/ CP - 3 J1 - Clim. Res. M3 - 10.3354/cr01310 ER - TY - JOUR T1 - Hybrid Vibrio cholerae El Tor Lacking SXT Identified as the Cause of a Cholera Outbreak in the Philippines JF - mBio Y1 - 2015 A1 - Klinzing, David C. A1 - Choi, Seon Young A1 - Hasan, Nur A. A1 - Matias, Ronald R. A1 - Tayag, Enrique A1 - Geronimo, Josefina A1 - Skowronski, Evan A1 - Rashed, Shah M. A1 - Kawashima, Kent A1 - Rosenzweig, C. Nicole A1 - Gibbons, Henry S. A1 - Torres, Brian C. A1 - Liles, Veni A1 - Alfon, Alicia C. A1 - Juan, Maria Luisa A1 - Natividad, Filipinas F. A1 - Cebula, Thomas A. A1 - Rita R Colwell AB - Cholera continues to be a global threat, with high rates of morbidity and mortality. In 2011, a cholera outbreak occurred in Palawan, Philippines, affecting more than 500 people, and 20 individuals died. Vibrio cholerae O1 was confirmed as the etiological agent. Source attribution is critical in cholera outbreaks for proper management of the disease, as well as to control spread. In this study, three V. cholerae O1 isolates from a Philippines cholera outbreak were sequenced and their genomes analyzed to determine phylogenetic relatedness to V. cholerae O1 isolates from recent outbreaks of cholera elsewhere. The Philippines V. cholerae O1 isolates were determined to be V. cholerae O1 hybrid El Tor belonging to the seventh-pandemic clade. They clustered tightly, forming a monophyletic clade closely related to V. cholerae O1 hybrid El Tor from Asia and Africa. The isolates possess a unique multilocus variable-number tandem repeat analysis (MLVA) genotype (12-7-9-18-25 and 12-7-10-14-21) and lack SXT. In addition, they possess a novel 15-kb genomic island (GI-119) containing a predicted type I restriction-modification system. The CTXΦ-RS1 array of the Philippines isolates was similar to that of V. cholerae O1 MG116926, a hybrid El Tor strain isolated in Bangladesh in 1991. Overall, the data indicate that the Philippines V. cholerae O1 isolates are unique, differing from recent V. cholerae O1 isolates from Asia, Africa, and Haiti. Furthermore, the results of this study support the hypothesis that the Philippines isolates of V. cholerae O1 are indigenous and exist locally in the aquatic ecosystem of the Philippines. UR - http://mbio.asm.org/lookup/doi/10.1128/mBio.00047-15 CP - 2 J1 - mBio M3 - 10.1128/mBio.00047-15 ER - TY - JOUR T1 - Molecular tools in understanding the evolution of Vibrio cholerae JF - Frontiers in Microbiology Y1 - 2015 A1 - Rahaman, Md. Habibur A1 - Islam, Tarequl A1 - Rita R Colwell A1 - Alam, Munirul AB - Vibrio cholerae, the etiological agent of cholera, has been a scourge for centuries. Cholera remains a serious health threat for developing countries and has been responsible for millions of deaths globally over the past 200 years. Identification of V. cholerae has been accomplished using a variety of methods, ranging from phenotypic strategies to DNA based molecular typing and currently whole genomic approaches. This array of methods has been adopted in epidemiological investigations, either singly or in the aggregate, and more recently for evolutionary analyses of V. cholerae. Because the new technologies have been developed at an ever increasing pace, this review of the range of fingerprinting strategies, their relative advantages and limitations, and cholera case studies was undertaken. The task was challenging, considering the vast amount of the information available. To assist the study, key references representative of several areas of research are provided with the intent to provide readers with a comprehensive view of recent advances in the molecular epidemiology of V. cholerae. Suggestions for ways to obviate many of the current limitations of typing techniques are also provided. In summary, a comparative report has been prepared that includes the range from traditional typing to whole genomic strategies. UR - http://journal.frontiersin.org/Article/10.3389/fmicb.2015.01040/abstract CP - e0120311154e00398-13822020380817190 J1 - Front. Microbiol. M3 - 10.3389/fmicb.2015.01040 ER - TY - JOUR T1 - Predictive Time Series Analysis Linking Bengal Cholera with Terrestrial Water Storage Measured from Gravity Recovery and Climate Experiment Sensors JF - The American Journal of Tropical Medicine and Hygiene Y1 - 2015 A1 - Rita R Colwell A1 - Unnikrishnan, Avinash A1 - Jutla, Antarpreet A1 - Huq, Anwar A1 - Akanda, Ali AB - Outbreaks of diarrheal diseases, including cholera, are related to floods and droughts in regions where water and sanitation infrastructure are inadequate or insufficient. However, availability of data on water scarcity and abundance in transnational basins, are a prerequisite for developing cholera forecasting systems. With more than a decade of terrestrial water storage (TWS) data from the Gravity Recovery and Climate Experiment, conditions favorable for predicting cholera occurrence may now be determined. We explored lead–lag relationships between TWS in the Ganges–Brahmaputra–Meghna basin and endemic cholera in Bangladesh. Since bimodal seasonal peaks in cholera in Bangladesh occur during spring and autumn seasons, two separate logistical models between TWS and disease time series (2002–2010) were developed. TWS representing water availability showed an asymmetrical, strong association with cholera prevalence in the spring (τ = −0.53; P < 0.001) and autumn (τ = 0.45; P < 0.001) up to 6 months in advance. One unit (centimeter of water) decrease in water availability in the basin increased odds of above normal cholera by 24% (confidence interval [CI] = 20–31%; P < 0.05) in the spring, while an increase in regional water by 1 unit, through floods, increased odds of above average cholera in the autumn by 29% (CI = 22–33%; P < 0.05). VL - 93 UR - http://www.ajtmh.org/content/journals/10.4269/ajtmh.14-0648 CP - 6 M3 - 10.4269/ajtmh.14-0648 ER - TY - JOUR T1 - Satellite Based Assessment of Hydroclimatic Conditions Related to Cholera in Zimbabwe JF - PLOS ONE Y1 - 2015 A1 - Jutla, Antarpreet A1 - Aldaach, Haidar A1 - Billian, Hannah A1 - Akanda, Ali A1 - Huq, Anwar A1 - Rita R Colwell ED - Schumann, Guy J-P. AB - Introduction Cholera, an infectious diarrheal disease, has been shown to be associated with large scale hydroclimatic processes. The sudden and sporadic occurrence of epidemic cholera is linked with high mortality rates, in part, due to uncertainty in timing and location of outbreaks. Improved understanding of the relationship between pathogenic abundance and climatic processes allows prediction of disease outbreak to be an achievable goal. In this study, we show association of large scale hydroclimatic processes with the cholera epidemic in Zimbabwe reported to have begun in Chitungwiza, a city in Mashonaland East province, in August, 2008. Principal Findings Climatic factors in the region were found to be associated with triggering cholera outbreak and are shown to be related to anomalies of temperature and precipitation, validating the hypothesis that poor conditions of sanitation, coupled with elevated temperatures, and followed by heavy rainfall can initiate outbreaks of cholera. Spatial estimation by satellite of precipitation and global gridded air temperature captured sensitivities in hydroclimatic conditions that permitted identification of the location in the region where the disease outbreak began. Discussion Satellite derived hydroclimatic processes can be used to capture environmental conditions related to epidemic cholera, as occurred in Zimbabwe, thereby providing an early warning system. Since cholera cannot be eradicated because the causative agent, Vibrio cholerae, is autochthonous to the aquatic environment, prediction of conditions favorable for its growth and estimation of risks of triggering the disease in a given population can be used to alert responders, potentially decreasing infection and saving lives. UR - https://dx.plos.org/10.1371/journal.pone.0137828 CP - 9Suppl 1 J1 - PLoS ONE M3 - 10.1371/journal.pone.0137828 ER - TY - JOUR T1 - A unified initiative to harness Earth's microbiomes JF - Science Y1 - 2015 A1 - Alivisatos, A. P. A1 - Blaser, M. J. A1 - Brodie, E. L. A1 - Chun, M. A1 - Dangl, J. L. A1 - Donohue, T. J. A1 - Dorrestein, P. C. A1 - Gilbert, J. A. A1 - Green, J. L. A1 - Jansson, J. K. A1 - Knight, R. A1 - Maxon, M. E. A1 - McFall-Ngai, M. J. A1 - Miller, J. F. A1 - Pollard, K. S. A1 - Ruby, E. G. A1 - Taha, S. A. A1 - Rita R Colwell UR - http://www.sciencemag.org/cgi/doi/10.1126/science.aac8480 CP - 62607551614341176 J1 - Science M3 - 10.1126/science.aac8480 ER - TY - JOUR T1 - Global diarrhoea action plan needs integrated climate-based surveillance JF - The Lancet Global Health Y1 - 2014 A1 - Akanda, Ali S A1 - Jutla, Antarpreet S A1 - Rita R Colwell VL - 2 UR - https://linkinghub.elsevier.com/retrieve/pii/S2214109X13701554 CP - 2 J1 - The Lancet Global Health M3 - 10.1016/S2214-109X(13)70155-4 ER - TY - JOUR T1 - Microbial Community Profiling of Human Saliva Using Shotgun Metagenomic Sequencing JF - PLoS ONE Y1 - 2014 A1 - Hasan, Nur A. A1 - Young, Brian A. A1 - Minard-Smith, Angela T. A1 - Saeed, Kelly A1 - Li, Huai A1 - Heizer, Esley M. A1 - McMillan, Nancy J. A1 - Isom, Richard A1 - Abdullah, Abdul Shakur A1 - Bornman, Daniel M. A1 - Faith, Seth A. A1 - Choi, Seon Young A1 - Dickens, Michael L. A1 - Cebula, Thomas A. A1 - Rita R Colwell ED - Ahmed, Niyaz AB - Human saliva is clinically informative of both oral and general health. Since next generation shotgun sequencing (NGS) is now widely used to identify and quantify bacteria, we investigated the bacterial flora of saliva microbiomes of two healthy volunteers and five datasets from the Human Microbiome Project, along with a control dataset containing short NGS reads from bacterial species representative of the bacterial flora of human saliva. GENIUS, a system designed to identify and quantify bacterial species using unassembled short NGS reads was used to identify the bacterial species comprising the microbiomes of the saliva samples and datasets. Results, achieved within minutes and at greater than 90% accuracy, showed more than 175 bacterial species comprised the bacterial flora of human saliva, including bacteria known to be commensal human flora but also Haemophilus influenzae, Neisseria meningitidis, Streptococcus pneumoniae, and Gamma proteobacteria. Basic Local Alignment Search Tool (BLASTn) analysis in parallel, reported ca. five times more species than those actually comprising the in silico sample. Both GENIUS and BLAST analyses of saliva samples identified major genera comprising the bacterial flora of saliva, but GENIUS provided a more precise description of species composition, identifying to strain in most cases and delivered results at least 10,000 times faster. Therefore, GENIUS offers a facile and accurate system for identification and quantification of bacterial species and/or strains in metagenomic samples. UR - https://dx.plos.org/10.1371/journal.pone.0097699 CP - 5 J1 - PLoS ONE M3 - 10.1371/journal.pone.0097699 ER - TY - JOUR T1 - Occurrence in Mexico, 1998–2008, of Vibrio cholerae CTX + El Tor carrying an additional truncated CTX prophage JF - Proceedings of the National Academy of Sciences Y1 - 2014 A1 - Alam, Munirul A1 - Rashed, Shah M A1 - Mannan, Shahnewaj Bin A1 - Islam, Tarequl A1 - Lizarraga-Partida, Marcial L. A1 - Delgado, Gabriela A1 - Morales-Espinosa, Rosario A1 - Mendez, Jose Luis A1 - Navarro, Armando A1 - Watanabe, Haruo A1 - Ohnishi, Makoto A1 - Hasan, Nur A. A1 - Huq, Anwar A1 - Sack, R. Bradley A1 - Rita R Colwell A1 - Cravioto, Alejandro VL - 111 UR - http://www.pnas.org/lookup/doi/10.1073/pnas.1323408111 CP - 27 J1 - Proc Natl Acad Sci USA M3 - 10.1073/pnas.1323408111 ER - TY - JOUR T1 - Phylodynamic Analysis of Clinical and Environmental Vibrio cholerae Isolates from Haiti Reveals Diversification Driven by Positive Selection JF - mBio Y1 - 2014 A1 - Azarian, Taj A1 - Ali, Afsar A1 - Johnson, Judith A. A1 - Mohr, David A1 - Prosperi, Mattia A1 - Veras, Nazle M. A1 - Jubair, Mohammed A1 - Strickland, Samantha L. A1 - Rashid, Mohammad H. A1 - Alam, Meer T. A1 - Weppelmann, Thomas A. A1 - Katz, Lee S. A1 - Tarr, Cheryl L. A1 - Rita R Colwell A1 - Morris, J. Glenn A1 - Salemi, Marco AB - Phylodynamic analysis of genome-wide single-nucleotide polymorphism (SNP) data is a powerful tool to investigate underlying evolutionary processes of bacterial epidemics. The method was applied to investigate a collection of 65 clinical and environmental isolates of Vibrio cholerae from Haiti collected between 2010 and 2012. Characterization of isolates recovered from environmental samples identified a total of four toxigenic V. cholerae O1 isolates, four non-O1/O139 isolates, and a novel nontoxigenic V. cholerae O1 isolate with the classical tcpA gene. Phylogenies of strains were inferred from genome-wide SNPs using coalescent-based demographic models within a Bayesian framework. A close phylogenetic relationship between clinical and environmental toxigenic V. cholerae O1 strains was observed. As cholera spread throughout Haiti between October 2010 and August 2012, the population size initially increased and then fluctuated over time. Selection analysis along internal branches of the phylogeny showed a steady accumulation of synonymous substitutions and a progressive increase of nonsynonymous substitutions over time, suggesting diversification likely was driven by positive selection. Short-term accumulation of nonsynonymous substitutions driven by selection may have significant implications for virulence, transmission dynamics, and even vaccine efficacy. UR - http://mbio.asm.org/lookup/doi/10.1128/mBio.01824-14 CP - 6 J1 - mBio M3 - 10.1128/mBio.01824-14 ER - TY - JOUR T1 - Bear-with-me: an embodied prototype to explore tangible two-way exchanges of emotional language JF - CHI'13 Extended Abstracts on Human Factors in Computing Systems Y1 - 2013 A1 - Fong, A A1 - Ashktorab, Z A1 - Jon Froehlich AB - Abstract Given the busy day-to-day schedule of families and couples, communication between loved ones is often limited to text-messaging, email, or phone calls. These forms of communication do not allow for more tangible modes of intimate expression like hugging. ... UR - http://dl.acm.org/citation.cfm?id=2468537 ER - TY - JOUR T1 - Clutter noise removal in binary document images JF - International Journal on Document Analysis and Recognition (IJDAR) Y1 - 2013 A1 - Agrawal, Mudit A1 - David Doermann AB - Abstract The paper presents a clutter detection and removal algorithm for complex document images. This distance transform based technique aims to remove irregular and independent unwanted clutter while preserving the text content. The novelty of this approach is in its ... PB - Springer Berlin Heidelberg VL - 16 UR - http://link.springer.com/article/10.1007/s10032-012-0196-6/fulltext.html CP - 4 J1 - IJDAR M3 - 10.1007/s10032-012-0196-6 ER - TY - JOUR T1 - Detection of Vibrio cholerae in environmental waters including drinking water reservoirs of Azerbaijan JF - Environmental Microbiology Reports Y1 - 2013 A1 - Rashid, Ahmadov A1 - Haley, Bradd J. A1 - Rajabov, Mukhtar A1 - Ahmadova, Sevinj A1 - Gurbanov, Shair A1 - Rita R Colwell A1 - Huq, Anwar UR - https://onlinelibrary.wiley.com/doi/10.1111/j.1758-2229.2012.00369.x CP - 1 J1 - Environmental Microbiology Reports M3 - 10.1111/j.1758-2229.2012.00369.x ER - TY - JOUR T1 - Dirichlet Mixtures, the Dirichlet Process, and the Structure of Protein Space JF - Journal of Computational Biology Y1 - 2013 A1 - Nguyen,Viet-An A1 - Jordan Boyd-Graber A1 - Altschul, Stephen F. KW - ALIGNMENT KW - computational molecular biology KW - dynamic programming KW - multiple alignment KW - sequence analysis AB - The Dirichlet process is used to model probability distributions that are mixtures of an unknown number of components. Amino acid frequencies at homologous positions within related proteins have been fruitfully modeled by Dirichlet mixtures, and we use the Dirichlet process to derive such mixtures with an unbounded number of components. This application of the method requires several technical innovations to sample an unbounded number of Dirichlet-mixture components. The resulting Dirichlet mixtures model multiple-alignment data substantially better than do previously derived ones. They consist of over 500 components, in contrast to fewer than 40 previously, and provide a novel perspective on the structure of proteins. Individual protein positions should be seen not as falling into one of several categories, but rather as arrayed near probability ridges winding through amino acid multinomial space. VL - 20 M3 - 10.1089/cmb.2012.0244 ER - TY - JOUR T1 - Distribution of Virulence Genes in Clinical and Environmental Vibrio cholerae Strains in Bangladesh JF - Applied and Environmental Microbiology Y1 - 2013 A1 - Hasan, Nur A. A1 - Ceccarelli, Daniela A1 - Grim, Christopher J. A1 - Taviani, Elisa A1 - Choi, Jinna A1 - Sadique, Abdus A1 - Alam, Munirul A1 - Siddique, Abul K. A1 - Sack, R. Bradley A1 - Huq, Anwar A1 - Rita R Colwell AB - Vibrio cholerae, an environmental organism, is a facultative human pathogen. Here, we report the virulence profiles, comprising 18 genetic markers, of 102 clinical and 692 environmental V. cholerae strains isolated in Bangladesh between March 2004 and January 2006, showing the variability of virulence determinants within the context of public health. UR - http://aem.asm.org/lookup/doi/10.1128/AEM.01113-13 CP - 18 J1 - Appl. Environ. Microbiol. M3 - 10.1128/AEM.01113-13 ER - TY - JOUR T1 - Drug response and genetic properties of Vibrio cholerae associated with endemic cholera in north-eastern Thailand, 2003-2011 JF - Journal of Medical Microbiology Y1 - 2013 A1 - Chomvarin, C. A1 - Johura, F.-T. A1 - Mannan, S. B. A1 - Jumroenjit, W. A1 - Kanoktippornchai, B. A1 - Tangkanakul, W. A1 - Tantisuwichwong, N. A1 - Huttayananont, S. A1 - Watanabe, H. A1 - Hasan, N. A. A1 - Huq, A. A1 - Cravioto, A. A1 - Rita R Colwell A1 - Alam, M. AB - Cholera, caused by Vibrio cholerae, results in significant morbidity and mortality worldwide, including Thailand. Representative V. cholerae strains associated with endemic cholera (n = 32), including strains (n = 3) from surface water sources, in Khon Kaen, Thailand (2003–2011), were subjected to microbiological, molecular and phylogenetic analyses. According to phenotypic and related genetic data, all tested V. cholerae strains belonged to serogroup O1, biotype El Tor (ET), Inaba (IN) or Ogawa (OG). All of the strains were sensitive to gentamicin and ciprofloxacin, while multidrug-resistant (MDR) strains showing resistance to erythromycin, tetracycline, trimethoprim/sulfamethoxazole and ampicillin were predominant in 2007. V. cholerae strains isolated before and after 2007 were non-MDR. All except six diarrhoeal strains possessed ctxA and ctxB genes and were toxigenic altered ET, confirmed by MAMA-PCR and DNA sequencing. Year-wise data revealed that V. cholerae INET strains isolated between 2003 and 2004, plus one strain isolated in 2007, lacked the RS1 sequence (rstC) and toxin-linked cryptic plasmid (TLC)-specific genetic marker, but possessed CTXCL prophage genes ctxB CL and rstR CL. A sharp genetic transition was noted, namely the majority of V. cholerae strains in 2007 and all in 2010 and 2011 were not repressor genotype rstR CL but instead were rstR ET, and all ctx + strains possessed RS1 and TLC-specific genetic markers. DNA sequencing data revealed that strains isolated since 2007 had a mutation in the tcpA gene at amino acid position 64 (N→S). Four clonal types, mostly of environmental origin, including subtypes, reflected genetic diversity, while distinct signatures were observed for clonally related, altered ET from Thailand, Vietnam and Bangladesh, confirmed by distinct subclustering patterns observed in the PFGE (NotI)-based dendrogram, suggesting that endemic cholera is caused by V. cholerae indigenous to Khon Kaen. UR - http://jmm.microbiologyresearch.org/content/journal/jmm/10.1099/jmm.0.053801-0 J1 - Journal of Medical Microbiology M3 - 10.1099/jmm.0.053801-0 ER - TY - JOUR T1 - Engaging Actively with Issues in the Responsible Conduct of Science: Lessons from International Efforts Are Relevant for Undergraduate Education in the United States JF - CBE—Life Sciences Education Y1 - 2013 A1 - Clements, John D. A1 - Connell, Nancy D. A1 - Dirks, Clarissa A1 - El-Faham, Mohamed A1 - Hay, Alastair A1 - Heitman, Elizabeth A1 - Stith, James H. A1 - Bond, Enriqueta C. A1 - Rita R Colwell A1 - Anestidou, Lida A1 - Husbands, Jo L. A1 - Labov, Jay B. AB - Numerous studies are demonstrating that engaging undergraduate students in original research can improve their achievement in the science, technology, engineering, and mathematics (STEM) fields and increase the likelihood that some of them will decide to pursue careers in these disciplines. Associated with this increased prominence of research in the undergraduate curriculum are greater expectations from funders, colleges, and universities that faculty mentors will help those students, along with their graduate students and postdoctoral fellows, develop an understanding and sense of personal and collective obligation for responsible conduct of science (RCS). This Feature describes an ongoing National Research Council (NRC) project and a recent report about educating faculty members in culturally diverse settings (Middle East/North Africa and Asia) to employ active-learning strategies to engage their students and colleagues deeply in issues related to RCS. The NRC report describes the first phase of this project, which took place in Aqaba and Amman, Jordan, in September 2012 and April 2013, respectively. Here we highlight the findings from that report and our subsequent experience with a similar interactive institute in Kuala Lumpur, Malaysia. Our work provides insights and perspectives for faculty members in the United States as they engage undergraduate and graduate students, as well as postdoctoral fellows, to help them better understand the intricacies of and connections among various components of RCS. Further, our experiences can provide insights for those who may wish to establish “train-the-trainer” programs at their home institutions. UR - https://www.lifescied.org/doi/10.1187/cbe.13-09-0184 CP - 4 J1 - LSE M3 - 10.1187/cbe.13-09-0184 ER - TY - JOUR T1 - Environmental Factors Influencing Epidemic Cholera JF - The American Journal of Tropical Medicine and Hygiene Y1 - 2013 A1 - Huq, Anwar A1 - Hasan, Nur A1 - Akanda, Ali A1 - Whitcombe, Elizabeth A1 - Rita R Colwell A1 - Haley, Bradd A1 - Alam, Munir A1 - Jutla, Antarpreet A1 - Sack, R. Bradley AB - Cholera outbreak following the earthquake of 2010 in Haiti has reaffirmed that the disease is a major public health threat. Vibrio cholerae is autochthonous to aquatic environment, hence, it cannot be eradicated but hydroclimatology-based prediction and prevention is an achievable goal. Using data from the 1800s, we describe uniqueness in seasonality and mechanism of occurrence of cholera in the epidemic regions of Asia and Latin America. Epidemic regions are located near regional rivers and are characterized by sporadic outbreaks, which are likely to be initiated during episodes of prevailing warm air temperature with low river flows, creating favorable environmental conditions for growth of cholera bacteria. Heavy rainfall, through inundation or breakdown of sanitary infrastructure, accelerates interaction between contaminated water and human activities, resulting in an epidemic. This causal mechanism is markedly different from endemic cholera where tidal intrusion of seawater carrying bacteria from estuary to inland regions, results in outbreaks. VL - 89 UR - http://www.ajtmh.org/content/journals/10.4269/ajtmh.12-0721 CP - 3 M3 - 10.4269/ajtmh.12-0721 ER - TY - JOUR T1 - Improving public transit accessibility for blind riders by crowdsourcing bus stop landmark locations with Google street view JF - The 15th International ACM SIGACCESS Conference Y1 - 2013 A1 - Hara, Kotaro A1 - Azenkot, Shiri A1 - Campbell, Megan A1 - Bennett, Cynthia L A1 - Le, Vicki A1 - Pannella, Sean A1 - Moore, Robert A1 - Minckler, Kelly A1 - Ng, Rochelle H A1 - Jon Froehlich AB - Abstract Low-vision and blind bus riders often rely on known physical landmarks to help locate and verify bus stop locations (eg., by searching for a shelter, bench, newspaper bin). However, there are currently few, if any, methods to determine this information a priori via ... PB - SIGACCESS, ACM Special Interest Group on Accessible ComputingACM CY - New York, New York, USA SN - 9781450324052 UR - http://dl.acm.org/citation.cfm?doid=2513383.2513448 J1 - ASSETS '13 M3 - 10.1145/2513383.2513448 ER - TY - CONF T1 - Large-Scale Signature Matching Using Multi-stage Hashing T2 - Document Analysis and Recognition (ICDAR), 2013 12th International Conference on Y1 - 2013 A1 - Du, Xianzhi A1 - Abdalmageed, W A1 - David Doermann AB - In this paper, we propose a fast large-scale signature matching method based on locality sensitive hashing (LSH). Shape Context features are used to describe the structure of signatures. Two stages of hashing are performed to find the nearest neighbours for query signatures. In the first stage, we use M randomly generated hyper planes to separate shape context feature points into different bins, and compute a term-frequency histogram to represent the feature point distribution as a feature vector. In the second stage we again use LSH to categorize the high-level features into different classes. The experiments are carried out on two datasets - DS-I, a small dataset contains 189 signatures, and DS-II, a large dataset created by our group which contains 26,000 signatures. We show that our algorithm can achieve a high accuracy even when few signatures are collected from one same person and perform fast matching when dealing with a large dataset. View full abstract JA - Document Analysis and Recognition (ICDAR), 2013 12th International Conference on PB - IEEE SN - 978-0-7695-4999-6 UR - http://ieeexplore.ieee.org/lpdocs/epic03/wrapper.htm?arnumber=6628762 M3 - 10.1109/ICDAR.2013.197 ER - TY - JOUR T1 - Species composition of limnetic zooplankton from the southern coastal areas (Mathbaria and Bakerganj) in Bangladesh JF - Journal of the Asiatic Society of Bangladesh, Science Y1 - 2013 A1 - Mozumder, Pronob K A1 - Nahar, Samsun A1 - Naser, M Niamul A1 - Alam, Munirul A1 - Huq, Anwar A1 - Sack, R Bradley A1 - Rita R Colwell AB - We studied the coastal zooplankton community structure of six waterbodies of Mathbaria and Bakerganj from January 2008 to June 2009. In total 35 zooplankton species were identified under 26 genera under 20 families under 8 orders from Mathbaria. Among them 6 were protozoans, 24 were rotifers, 3 were copepods, 1 was cladocerans and 1 was ostracods. From Bakergonj a total of 42 zooplankton species were identified under 23 genera under 17 Families under 7 orders. Among them 3 were protozoans, 25 were rotifers, 7 were copepods, 6 were cladocerans and 1 was ostracods. Results showed that abundance of rotifera group from both area was higher in Mathbaria (64.86%) and Bakerganj (60.98%) than other groups while abundance of ostracoda of Bakerganj area was lowest. VL - 38 UR - http://banglajol.info/index.php/JASBS/article/view/15326 CP - 1 J1 - J. Asiat. Soc. Bangladesh, Sci. M3 - 10.3329/jasbs.v38i1.15326 ER - TY - JOUR T1 - A water marker monitored by satellites to predict seasonal endemic cholera JF - Remote Sensing Letters Y1 - 2013 A1 - Jutla, Antarpreet A1 - Akanda, Ali Shafqat A1 - Huq, Anwar A1 - Faruque, Abu Syed Golam A1 - Rita R Colwell A1 - Islam, Shafiqul AB - The ability to predict an occurrence of cholera, a water-related disease, offers a significant public health advantage. Satellite-based estimates of chlorophyll, a surrogate for plankton abundance, have been linked to cholera incidence. However, cholera bacteria can survive under a variety of coastal ecological conditions, thus constraining the predictive ability of the chlorophyll, since it provides only an estimate of greenness of seawater. Here, a new remote-sensing-based index is proposed: Satellite Water Marker (SWM), which estimates the condition of coastal water, based on observed variability in the difference between blue (412 nm) and green (555 nm) wavelengths that can be related to seasonal cholera incidence. The index is bounded between physically separable wavelengths for relatively clear (blue) and turbid (green) water. Using SWM, prediction of cholera with reasonable accuracy, at least two months in advance, can potentially be achieved in the endemic coastal regions. VL - 4472741982394456 UR - http://www.tandfonline.com/doi/abs/10.1080/2150704X.2013.802097 CP - 8 J1 - Remote Sensing Letters M3 - 10.1080/2150704X.2013.802097 ER - TY - JOUR T1 - An additional step in the transmission of Yersinia pestis? JF - The ISME Journal Y1 - 2012 A1 - Easterday, W Ryan A1 - Kausrud, Kyrre L A1 - Star, Bastiaan A1 - Heier, Lise A1 - Haley, Bradd J A1 - Ageyev, Vladimir A1 - Rita R Colwell A1 - Stenseth, Nils Chr AB - Plague, caused by the bacterium Yersinia pestis, is a mammalian vector-borne disease, transmitted by fleas that serve as the vector between rodent hosts. For many pathogens, including Y. pestis, there are strong evolutionary pressures that lead to a reduction in ‘useless genes’, with only those retained that reflect function in the specific environment inhabited by the pathogen. Genetic traits critical for survival and transmission between two environments, the rodent and the flea, are conserved in epizootic/epidemic plague strains. However, there are genes that remain conserved for which no function in the flea–rodent cycle has yet been observed, indicating an additional environment may exist in the transmission cycle of plague. Here, we present evidence for highly conserved genes that suggests a role in the persistence of Y. pestis after death of its host. Furthermore, maintenance of these genes points to Y. pestis traversing a post-mortem path between, and possibly within, epizootic periods and offering insight into mechanisms that may allow Y. pestis an alternative route of transmission in the natural environment. UR - http://www.nature.com/articles/ismej2011105 CP - 2 J1 - ISME J M3 - 10.1038/ismej.2011.105 ER - TY - JOUR T1 - BEAGLE: An Application Programming Interface and High-Performance Computing Library for Statistical Phylogenetics JF - Systematic BiologySyst Biol Y1 - 2012 A1 - Ayres,Daniel L A1 - Darling,Aaron A1 - Zwickl,Derrick J A1 - Beerli,Peter A1 - Holder,Mark T A1 - Lewis,Paul O A1 - Huelsenbeck,John P A1 - Ronquist,Fredrik A1 - Swofford,David L A1 - Cummings, Michael P. A1 - Rambaut,Andrew A1 - Suchard,Marc A KW - Bayesian phylogenetics KW - gpu KW - maximum likelihood KW - parallel computing AB - Phylogenetic inference is fundamental to our understanding of most aspects of the origin and evolution of life, and in recent years, there has been a concentration of interest in statistical approaches such as Bayesian inference and maximum likelihood estimation. Yet, for large data sets and realistic or interesting models of evolution, these approaches remain computationally demanding. High-throughput sequencing can yield data for thousands of taxa, but scaling to such problems using serial computing often necessitates the use of nonstatistical or approximate approaches. The recent emergence of graphics processing units (GPUs) provides an opportunity to leverage their excellent floating-point computational performance to accelerate statistical phylogenetic inference. A specialized library for phylogenetic calculation would allow existing software packages to make more effective use of available computer hardware, including GPUs. Adoption of a common library would also make it easier for other emerging computing architectures, such as field programmable gate arrays, to be used in the future. We present BEAGLE, an application programming interface (API) and library for high-performance statistical phylogenetic inference. The API provides a uniform interface for performing phylogenetic likelihood calculations on a variety of compute hardware platforms. The library includes a set of efficient implementations and can currently exploit hardware including GPUs using NVIDIA CUDA, central processing units (CPUs) with Streaming SIMD Extensions and related processor supplementary instruction sets, and multicore CPUs via OpenMP. To demonstrate the advantages of a common API, we have incorporated the library into several popular phylogenetic software packages. The BEAGLE library is free open source software licensed under the Lesser GPL and available from http://beagle-lib.googlecode.com. An example client program is available as public domain software. VL - 61 SN - 1063-5157, 1076-836X UR - http://sysbio.oxfordjournals.org/content/61/1/170 CP - 1 M3 - 10.1093/sysbio/syr100 ER - TY - JOUR T1 - Biases from model assumptions in texture sub-cellular image segmentation JF - SPIE Newsroom Y1 - 2012 A1 - Cardone, Antonio A1 - Amelot, Julien A1 - Li-Baboud, Ya-Shian A1 - Brady, Mary A1 - Bajcsy, Peter VL - 13 ER - TY - JOUR T1 - Disaggregated water sensing from a single, pressure-based sensor: An extended analysis of HydroSense using staged experiments JF - Pervasive and Mobile Computing Y1 - 2012 A1 - Larson,Eric A1 - Jon Froehlich A1 - Campbell,Tim A1 - Haggerty,Conor A1 - Atlas,Les A1 - Fogarty,James A1 - Patel,Shwetak N. KW - Activity sensing KW - H1.2 KW - H5.2 KW - Infrastructure-mediated sensing KW - Sensors KW - Water usage AB - We present an extended analysis of our previous work on the HydroSense technology, which is a low-cost and easily installed single-point sensor of pressure for automatically disaggregating water usage activities in the home (Froehlich et al., 2009 [53]). We expand upon this work by providing a survey of existing and emerging water disaggregation techniques, a more comprehensive description of the theory of operation behind our approach, and an expanded analysis section that includes hot versus cold water valve usage classification and a comparison between two classification approaches: the template-based matching scheme used in Froehlich et al. (2009) [53] and a new stochastic approach using a Hidden Markov Model. We show that both are successful in identifying valve- and fixture-level water events with greater than 90% accuracies. We conclude with a discussion of the limitations in our experimental methodology and open problems going forward. VL - 8 SN - 1574-1192 UR - http://www.sciencedirect.com/science/article/pii/S1574119210000842 CP - 1 M3 - 10.1016/j.pmcj.2010.08.008 ER - TY - JOUR T1 - Fast track article: Disaggregated water sensing from a single, pressure-based sensor: An extended analysis of HydroSense using staged experiments JF - Pervasive Mob. Comput. Y1 - 2012 A1 - Larson,Eric A1 - Jon Froehlich A1 - Campbell,Tim A1 - Haggerty,Conor A1 - Atlas,Les A1 - Fogarty,James A1 - Patel,Shwetak N. KW - Activity sensing KW - H1.2 KW - H5.2 KW - Infrastructure-mediated sensing KW - Sensors KW - Water usage AB - We present an extended analysis of our previous work on the HydroSense technology, which is a low-cost and easily installed single-point sensor of pressure for automatically disaggregating water usage activities in the home (Froehlich et al., 2009 [53]). We expand upon this work by providing a survey of existing and emerging water disaggregation techniques, a more comprehensive description of the theory of operation behind our approach, and an expanded analysis section that includes hot versus cold water valve usage classification and a comparison between two classification approaches: the template-based matching scheme used in Froehlich et al. (2009) [53] and a new stochastic approach using a Hidden Markov Model. We show that both are successful in identifying valve- and fixture-level water events with greater than 90% accuracies. We conclude with a discussion of the limitations in our experimental methodology and open problems going forward. VL - 8 SN - 1574-1192 UR - http://dx.doi.org/10.1016/j.pmcj.2010.08.008 CP - 1 M3 - 10.1016/j.pmcj.2010.08.008 ER - TY - JOUR T1 - A framework for human microbiome research JF - Nature Y1 - 2012 A1 - Methé, B.A. A1 - Nelson,K. E A1 - Pop, Mihai A1 - Creasy, H.H. A1 - Giglio, M.G. A1 - Huttenhower, C. A1 - Gevers, D. A1 - Petrosino, J.F. A1 - Abubucker, S. A1 - Badger, J.H. AB - A variety of microbial communities and their genes (the microbiome) exist throughout the human body, with fundamental roles in human health and disease. The National Institutes of Health (NIH)-funded Human Microbiome Project Consortium has established a population-scale framework to develop metagenomic protocols, resulting in a broad range of quality-controlled resources and data including standardized methods for creating, processing and interpreting distinct types of high-throughput metagenomic data available to the scientific community. Here we present resources from a population of 242 healthy adults sampled at 15 or 18 body sites up to three times, which have generated 5,177 microbial taxonomic profiles from 16S ribosomal RNA genes and over 3.5 terabases of metagenomic sequence so far. In parallel, approximately 800 reference strains isolated from the human body have been sequenced. Collectively, these data represent the largest resource describing the abundance and variety of the human microbiome, while providing a framework for current and future studies. VL - 486 ER - TY - JOUR T1 - Genetic characteristics of drug-resistant Vibrio cholerae O1 causing endemic cholera in Dhaka, 2006-2011 JF - Journal of Medical Microbiology Y1 - 2012 A1 - Rashed, S. M. A1 - Mannan, S. B. A1 - Johura, F.-T. A1 - Islam, M. T. A1 - Sadique, A. A1 - Watanabe, H. A1 - Sack, R. B. A1 - Huq, A. A1 - Rita R Colwell A1 - Cravioto, A. A1 - Alam, M. AB - Vibrio cholerae O1 biotype El Tor (ET), causing the seventh cholera pandemic, was recently replaced in Bangladesh by an altered ET possessing ctxB of the Classical (CL) biotype, which caused the first six cholera pandemics. In the present study, V. cholerae O1 strains associated with endemic cholera in Dhaka between 2006 and 2011 were analysed for major phenotypic and genetic characteristics. Of 54 representative V. cholerae isolates tested, all were phenotypically ET and showed uniform resistance to trimethoprim/sulfamethoxazole (SXT) and furazolidone (FR). Resistance to tetracycline (TE) and erythromycin (E) showed temporal fluctuation, varying from year to year, while all isolates were susceptible to gentamicin (CN) and ciprofloxacin (CIP). Year-wise data revealed erythromycin resistance to be 33.3 % in 2006 and 11 % in 2011, while tetracycline resistance accounted for 33, 78, 0, 100 and 27 % in 2006, 2007, 2008, 2009 and 2010, respectively; interestingly, all isolates tested were sensitive to TE in 2011, as observed in 2008. All V. cholerae isolates tested possessed genetic elements such as SXT, ctxAB, tcpA ET, rstR ET and rtxC; none had IntlI (Integron I). Double mismatch amplification mutation assay (DMAMA)-PCR followed by DNA sequencing and analysis of the ctxB gene revealed a point mutation at position 58 (C→A), which has resulted in an amino acid substitution from histidine (H) to asparagine (N) at position 20 (genotype 7) since 2008. Although the multi-resistant strains having tetracycline resistance showed minor genetic divergence, V. choleraestrains were clonal, as determined by a PFGE (NotI)-based dendrogram. This study shows 2008–2010 to be the time of transition from ctxB genotype 1 to genotype 7 in V. cholerae ET causing endemic cholera in Dhaka, Bangladesh. UR - http://jmm.microbiologyresearch.org/content/journal/jmm/10.1099/jmm.0.049635-0 J1 - Journal of Medical Microbiology M3 - 10.1099/jmm.0.049635-0 ER - TY - JOUR T1 - Genomic diversity of 2010 Haitian cholera outbreak strains JF - Proceedings of the National Academy of Sciences Y1 - 2012 A1 - Hasan, N. A. A1 - Choi, S. Y. A1 - Eppinger, M. A1 - Clark, P. W. A1 - Chen, A. A1 - Alam, M. A1 - Haley, B. J. A1 - Taviani, E. A1 - Hine, E. A1 - Su, Q. A1 - Tallon, L. J. A1 - Prosper, J. B. A1 - Furth, K. A1 - Hoq, M. M. A1 - Li, H. A1 - Fraser-Liggett, C. M. A1 - Cravioto, A. A1 - Huq, A. A1 - Ravel, J. A1 - Cebula, T. A. A1 - Rita R Colwell UR - http://www.pnas.org/cgi/doi/10.1073/pnas.1207359109 J1 - Proceedings of the National Academy of Sciences M3 - 10.1073/pnas.1207359109 ER - TY - JOUR T1 - Global secretome analysis identifies novel mediators of bone metastasis JF - Cell Research Y1 - 2012 A1 - Blanco, Mario Andres A1 - LeRoy, Gary A1 - Zia Khan A1 - Alečković, Maša A1 - Zee, Barry M. A1 - Garcia, Benjamin A. A1 - Kang, Yibin KW - bone KW - cancer KW - metastasis KW - proteomics KW - secretome AB - Bone is the one of the most common sites of distant metastasis of solid tumors. Secreted proteins are known to influence pathological interactions between metastatic cancer cells and the bone stroma. To comprehensively profile secreted proteins associated with bone metastasis, we used quantitative and non-quantitative mass spectrometry to globally analyze the secretomes of nine cell lines of varying bone metastatic ability from multiple species and cancer types. By comparing the secretomes of parental cells and their bone metastatic derivatives, we identified the secreted proteins that were uniquely associated with bone metastasis in these cell lines. We then incorporated bioinformatic analyses of large clinical metastasis datasets to obtain a list of candidate novel bone metastasis proteins of several functional classes that were strongly associated with both clinical and experimental bone metastasis. Functional validation of selected proteins indicated that in vivo bone metastasis can be promoted by high expression of (1) the salivary cystatins CST1, CST2, and CST4; (2) the plasminogen activators PLAT and PLAU; or (3) the collagen functionality proteins PLOD2 and COL6A1. Overall, our study has uncovered several new secreted mediators of bone metastasis and therefore demonstrated that secretome analysis is a powerful method for identification of novel biomarkers and candidate therapeutic targets. VL - 22 SN - 1001-0602 UR - http://www.nature.com/cr/journal/v22/n9/abs/cr201289a.html CP - 9 J1 - Cell Res ER - TY - JOUR T1 - Grey-box GUI Testing: Efficient Generation of Event Sequences JF - arXiv:1205.4928 Y1 - 2012 A1 - Arlt,Stephan A1 - Banerjee,Ishan A1 - Bertolini,Cristiano A1 - Memon, Atif M. A1 - Schäf,Martin KW - 68N30 KW - Computer Science - Software Engineering AB - Graphical user interfaces (GUIs), due to their event driven nature, present a potentially unbounded space of all possible ways to interact with software. During testing it becomes necessary to effectively sample this space. In this paper we develop algorithms that sample the GUI's input space by only generating sequences that (1) are allowed by the GUI's structure, and (2) chain together only those events that have data dependencies between their event handlers. We create a new abstraction, called an event-dependency graph (EDG) of the GUI, that captures data dependencies between event handler code. We develop a mapping between EDGs and an existing black-box user-level model of the GUI's workflow, called an event-flow graph (EFG). We have implemented automated EDG construction in a tool that analyzes the bytecode of each event handler. We evaluate our "grey-box" approach using four open-source applications and compare it with the current state-of-the-art EFG approach. Our results show that using the EDG reduces the number of test cases while still achieving at least the same coverage. Furthermore, we were able to detect 2 new bugs in the subject applications. UR - http://arxiv.org/abs/1205.4928 ER - TY - JOUR T1 - InterPro in 2011: new developments in the family and domain prediction database. JF - Nucleic Acids Res Y1 - 2012 A1 - Hunter, Sarah A1 - Jones, Philip A1 - Mitchell, Alex A1 - Apweiler, Rolf A1 - Attwood, Teresa K A1 - Bateman, Alex A1 - Bernard, Thomas A1 - Binns, David A1 - Bork, Peer A1 - Burge, Sarah A1 - de Castro, Edouard A1 - Coggill, Penny A1 - Corbett, Matthew A1 - Das, Ujjwal A1 - Daugherty, Louise A1 - Duquenne, Lauranne A1 - Finn, Robert D A1 - Fraser, Matthew A1 - Gough, Julian A1 - Haft, Daniel A1 - Hulo, Nicolas A1 - Kahn, Daniel A1 - Kelly, Elizabeth A1 - Letunic, Ivica A1 - Lonsdale, David A1 - Lopez, Rodrigo A1 - Madera, Martin A1 - Maslen, John A1 - McAnulla, Craig A1 - McDowall, Jennifer A1 - McMenamin, Conor A1 - Mi, Huaiyu A1 - Mutowo-Muellenet, Prudence A1 - Mulder, Nicola A1 - Natale, Darren A1 - Orengo, Christine A1 - Pesseat, Sebastien A1 - Punta, Marco A1 - Quinn, Antony F A1 - Rivoire, Catherine A1 - Sangrador-Vegas, Amaia A1 - Jeremy D Selengut A1 - Sigrist, Christian J A A1 - Scheremetjew, Maxim A1 - Tate, John A1 - Thimmajanarthanan, Manjulapramila A1 - Thomas, Paul D A1 - Wu, Cathy H A1 - Yeats, Corin A1 - Yong, Siew-Yit KW - Databases, Protein KW - Protein Structure, Tertiary KW - Proteins KW - Sequence Analysis, Protein KW - software KW - Terminology as Topic KW - User-Computer Interface AB -

InterPro (http://www.ebi.ac.uk/interpro/) is a database that integrates diverse information about protein families, domains and functional sites, and makes it freely available to the public via Web-based interfaces and services. Central to the database are diagnostic models, known as signatures, against which protein sequences can be searched to determine their potential function. InterPro has utility in the large-scale analysis of whole genomes and meta-genomes, as well as in characterizing individual protein sequences. Herein we give an overview of new developments in the database and its associated software since 2009, including updates to database content, curation processes and Web and programmatic interfaces.

VL - 40 CP - Database issue M3 - 10.1093/nar/gkr948 ER - TY - JOUR T1 - Vibrio Cholerae Classical Biotype Strains Reveal Distinct Signatures in Mexico JF - Journal of Clinical Microbiology Y1 - 2012 A1 - Alam,Munirul A1 - Islam,M. Tarequl A1 - Rashed,Shah Manzur A1 - Johura,Fatema-Tuz A1 - Bhuiyan,Nurul A. A1 - Delgado,Gabriela A1 - Morales,Rosario A1 - Mendez,Jose Luis A1 - Navarro,Armando A1 - Watanabe,Haruo A1 - Hasan,Nur-A. A1 - Rita R Colwell A1 - Cravioto,Alejandro AB - Vibrio cholerae O1 Classical (CL) biotype caused the 5th and 6th, and probably the earlier cholera pandemics, before the El Tor (ET) biotype initiated the 7th pandemic in Asia in the 1970's by completely displacing the CL biotype. Although the CL biotype was thought to be extinct in Asia, and it had never been reported from Latin America, V. cholerae CL and ET biotypes, including hybrid ET were found associated with endemic cholera in Mexico between 1991 and 1997. In this study, CL biotype strains isolated from endemic cholera in Mexico, between 1983 and 1997 were characterized in terms of major phenotypic and genetic traits, and compared with CL biotype strains isolated in Bangladesh between 1962 and 1989. According to sero- and bio-typing data, all V. cholerae strains tested had the major phenotypic and genotypic characteristics specific for the CL biotype. Antibiograms revealed the majority of the Bangladeshi strains to be resistant to trimethoprim/sulfamethoxazole, furazolidone, ampicillin, and gentamycin, while the Mexican strains were sensitive to all of these drugs, as well as to ciprofloxacin, erythromycin, and tetracycline. Pulsed-field gel electrophoresis (PFGE) of NotI-digested genomic DNA revealed characteristic banding patterns for all the CL biotype strains, although the Mexican strains differed with the Bangladeshi strains in 1-2 DNA bands. The difference may be subtle, but consistent, as confirmed by the sub-clustering patterns in the PFGE-based dendrogram, and can serve as regional signature, suggesting pre-1991 existence and evolution of the CL biotype strains in the Americas, independent from that of Asia. SN - 0095-1137, 1098-660X UR - http://jcm.asm.org/content/early/2012/04/12/JCM.00189-12 M3 - 10.1128/JCM.00189-12 ER - TY - CONF T1 - Mr. LDA: A Flexible Large Scale Topic Modeling Package using Variational Inference in MapReduce T2 - Proceedings of ACM International Conference on World Wide Web, 2012 Y1 - 2012 A1 - Zhai,Ke A1 - Jordan Boyd-Graber A1 - Asadi,Nima A1 - Alkhouja,Mohamad AB - Latent Dirichlet Allocation (LDA) is a popular topic modeling tech- nique for exploring document collections. Because of the increasing prevalence of large datasets, there is a need to improve the scal- ability of inference for LDA. In this paper, we introduce a novel and flexible large scale topic modeling package in MapReduce (Mr. LDA). As opposed to other techniques which use Gibbs sampling, our proposed framework uses variational inference, which easily fits into a distributed environment. More importantly, this variational implementation, unlike highly tuned and specialized implementa- tions based on Gibbs sampling, is easily extensible. We demonstrate two extensions of the models possible with this scalable framework: informed priors to guide topic discovery and extracting topics from a multilingual corpus. We compare the scalability of Mr. LDA against Mahout, an existing large scale topic modeling package. Mr. LDA out-performs Mahout both in execution speed and held-out likelihood. JA - Proceedings of ACM International Conference on World Wide Web, 2012 ER - TY - JOUR T1 - Occurrence of protozoans & their limnological relationships in some ponds of Mathbaria, Bangladesh JF - University Journal of Zoology, Rajshahi University Y1 - 2012 A1 - Mozumder,P. K. A1 - Banu,M. A. A1 - Naser,M. N. A1 - Ali,M. S. A1 - Alam,M. A1 - Sack,R. B. A1 - Rita R Colwell A1 - Huq,A. VL - 29 SN - 1023-6104 UR - http://journals.sfu.ca/bd/index.php/UJZRU CP - 1 ER - TY - CONF T1 - Polytope approximation and the Mahler volume T2 - Proceedings of the Twenty-Third Annual ACM-SIAM Symposium on Discrete Algorithms Y1 - 2012 A1 - Arya,Sunil A1 - da Fonseca,Guilherme D. A1 - Mount, Dave AB - The problem of approximating convex bodies by polytopes is an important and well studied problem. Given a convex body K in Rd, the objective is to minimize the number of vertices (alternatively, the number of facets) of an approximating polytope for a given Hausdorff error ε. Results to date have been of two types. The first type assumes that K is smooth, and bounds hold in the limit as ε tends to zero. The second type requires no such assumptions. The latter type includes the well known results of Dudley (1974) and Bronshteyn and Ivanov (1976), which show that in spaces of fixed dimension, O((diam(K)/ε)(d−1)/2) vertices (alt., facets) suffice. Our results are of this latter type. In our first result, under the assumption that the width of the body in any direction is at least ε, we strengthen the above bound to [EQUATION]. This is never worse than the previous bound (by more than logarithmic factors) and may be significantly better for skinny bodies. Our analysis exploits an interesting analogy with a classical concept from the theory of convexity, called the Mahler volume. This is a dimensionless quantity that involves the product of the volumes of a convex body and its polar dual. In our second result, we apply the same machinery to improve upon the best known bounds for answering ε-approximate polytope membership queries. Given a convex polytope P defined as the intersection of halfspaces, such a query determines whether a query point q lies inside or outside P, but may return either answer if q's distance from P's boundary is at most ε. We show that, without increasing storage, it is possible to reduce the best known search times for ε-approximate polytope membership significantly. This further implies improvements to the best known search times for approximate nearest neighbor searching in spaces of fixed dimension. JA - Proceedings of the Twenty-Third Annual ACM-SIAM Symposium on Discrete Algorithms T3 - SODA '12 PB - SIAM UR - http://dl.acm.org/citation.cfm?id=2095116.2095119 ER - TY - JOUR T1 - Quantitative measurement of allele‐specific protein expression in a diploid yeast hybrid by LC‐MS JF - Molecular Systems Biology Y1 - 2012 A1 - Zia Khan A1 - Bloom, Joshua S. A1 - Amini, Sasan A1 - Singh, Mona A1 - Perlman, David H. A1 - Caudy, Amy A. A1 - Kruglyak, Leonid KW - allele specific KW - divergence KW - mass spectrometry KW - protein expression KW - proteomics AB - Understanding the genetic basis of gene regulatory variation is a key goal of evolutionary and medical genetics. Regulatory variation can act in an allele‐specific manner (cis‐acting) or it can affect both alleles of a gene (trans‐acting). Differential allele‐specific expression (ASE), in which the expression of one allele differs from another in a diploid, implies the presence of cis‐acting regulatory variation. While microarrays and high‐throughput sequencing have enabled genome‐wide measurements of transcriptional ASE, methods for measurement of protein ASE (pASE) have lagged far behind. We describe a flexible, accurate, and scalable strategy for measurement of pASE by liquid chromatography‐coupled mass spectrometry (LC‐MS). We apply this approach to a hybrid between the yeast species Saccharomyces cerevisiae and Saccharomyces bayanus. Our results provide the first analysis of the relative contribution of cis‐acting and trans‐acting regulatory differences to protein expression divergence between yeast species.Synopsis A novel strategy for the quantitative measurement of allele‐specific protein expression is used to infer the contributions of cis‐ and trans‐acting factors influencing the divergence of protein levels between yeast species. Rigorous experimental controls and analyses confirm the accuracy of the new strategy for the quantitative measurement of allele‐specific protein expression by high‐throughput mass spectrometry.Analysis of allele‐specific protein expression in an interspecies yeast hybrid and protein expression differences between species reveals that both cis‐effects and trans‐effects contribute to protein expression divergence between two yeast species, Saccharomyces cerevisiae and Saccharomyces bayanus. VL - 8 UR - http://msb.embopress.org/content/8/1/602 CP - 1 ER - TY - JOUR T1 - Role of Shrimp Chitin in the Ecology of Toxigenic Vibrio cholerae and Cholera Transmission JF - Frontiers in Microbiology Y1 - 2012 A1 - Nahar,Shamsun A1 - Sultana,Marzia A1 - Naser,M. Niamul A1 - Nair,Gopinath B. A1 - Watanabe,Haruo A1 - Ohnishi,Makoto A1 - Yamamoto,Shouji A1 - Endtz,Hubert A1 - Cravioto,Alejandro A1 - Sack,R. Bradley A1 - Hasan,Nur A. A1 - Sadique,Abdus A1 - Huq,Anwar A1 - Rita R Colwell A1 - Alam,Munirul AB - Seasonal plankton blooms correlate with occurrence of cholera in Bangladesh, although the mechanism of how dormant Vibrio cholerae, enduring interepidemic period in biofilms and plankton, initiates seasonal cholera is not fully understood. In this study, laboratory microcosms prepared with estuarine Mathbaria water (MW) samples supported active growth of toxigenic V. cholerae O1 up to 7 weeks as opposed to 6 months when microcosms were supplemented with dehydrated shrimp chitin chips (CC) as the single source of nutrient. Bacterial counting and detection of wbe and ctxA genes were done employing culture, direct fluorescent antibody (DFA) assay, and multiplex-polymerase chain reaction methods. In MW microcosm, the aqueous phase became clear as the non-culturable cells settled, whereas the aqueous phase of the MW–CC microcosm became turbid from bacterial growth stimulated by chitin. Bacterial chitin degradation and biofilm formation proceeded from an initial steady state to a gradually declining bacterial culturable count. V. cholerae within the microenvironments of chitin and chitin-associated biofilms remained metabolically active even in a high acidic environment without losing either viability or virulence. It is concluded that the abundance of chitin that occurs during blooms plays an important role in the aquatic life cycle of V. cholerae and, ultimately, in the seasonal transmission of cholera. VL - 2:260 SN - 1664-302X M3 - 10.3389/fmicb.2011.00260 ER - TY - JOUR T1 - Structure, function and diversity of the healthy human microbiome JF - Nature Y1 - 2012 A1 - Huttenhower, C. A1 - Gevers, D. A1 - Knight,R. A1 - Abubucker, S. A1 - Badger, J.H. A1 - Chinwalla, A.T. A1 - Creasy, H.H. A1 - Earl, A.M. A1 - Fitzgerald, M.G. A1 - Fulton, R.S. A1 - others AB - Studies of the human microbiome have revealed that even healthy individuals differ remarkably in the microbes that occupy habitats such as the gut, skin and vagina. Much of this diversity remains unexplained, although diet, environment, host genetics and early microbial exposure have all been implicated. Accordingly, to characterize the ecology of human-associated microbial communities, the Human Microbiome Project has analysed the largest cohort and set of distinct, clinically relevant body habitats so far. We found the diversity and abundance of each habitat’s signature microbes to vary widely even among healthy subjects, with strong niche specialization both within and among individuals. The project encountered an estimated 81–99% of the genera, enzyme families and community configurations occupied by the healthy Western microbiome. Metagenomic carriage of metabolic pathways was stable among individuals despite variation in community structure, and ethnic/racial background proved to be one of the strongest associations of both pathways and microbes with clinical metadata. These results thus delineate the range of structural and functional configurations normal in the microbial communities of a healthy population, enabling future characterization of the epidemiology, ecology and translational applications of the human microbiome. VL - 486 ER - TY - PAT T1 - Systems and Methods for Energy Harvesting in a Contained Fluid Circuit Y1 - 2012 A1 - Campbell,Tim A1 - Larson,Eric A1 - Cohn, Gabriel A1 - Alcaide,Ramses A1 - Jon Froehlich A1 - Patel,Shwetak KW - Systems and Methods for Energy Harvesting in a Contained Fluid Circuit AB - Systems and methods for harvesting energy from a closed fluid circuit, such as a water pipe system in a building. An energy harvester can be installed at a point in a water circuit and can generate energy from pressure differentials caused when a valve is opened or closed at any other point in the water circuit that is in fluid communication with the energy harvester. The energy can be used to power, for example, a sensor and/or a transmitter., L'invention concerne des systèmes et des procédés de collecte de l'énergie qui provient d'un circuit de fluide fermé, comme un système de conduites d'eau dans un immeuble. Un collecteur d'énergie peut être installé à un certain point au sein d'un circuit d'eau et peut générer de l'énergie à partir des différentiels de pression provoqués lorsqu'une soupape est ouverte ou fermée à n'importe quel autre point au sein du circuit d'eau qui est en communication fluidique avec le collecteur d'énergie. L'énergie peut être utilisée pour alimenter, par exemple, un capteur et/ou un émetteur. PB - UNIVERSITY OF WASHINGTON THROUGH ITS CENTER FOR COMMERCIALIZATION, CAMPBELL, Tim, LARSON, Eric, COHN, Gabriel, ALCAIDE, Ramses, FROEHLICH, Jon, PATEL, Shwetak SN - WO/2012/021551 UR - http://patentscope.wipo.int/search/en/WO2012021551 ER - TY - JOUR T1 - Accelerated evolution of 3'avian FOXE1 genes, and thyroid and feather specific expression of chicken FoxE1 JF - BMC Evolutionary Biology Y1 - 2011 A1 - Yaklichkin,Sergey Yu A1 - Darnell,Diana K A1 - Pier,Maricela V A1 - Antin,Parker B A1 - Hannenhalli, Sridhar AB - The forkhead transcription factor gene E1 (FOXE1) plays an important role in regulation of thyroid development, palate formation and hair morphogenesis in mammals. However, avian FOXE1 genes have not been characterized and as such, codon evolution of FOXE1 orthologs in a broader evolutionary context of mammals and birds is not known. VL - 11 SN - 1471-2148 UR - http://www.biomedcentral.com/1471-2148/11/302 CP - 1 M3 - 10.1186/1471-2148-11-302 ER - TY - JOUR T1 - Accurate proteome-wide protein quantification from high-resolution 15N mass spectra JF - Genome Biology Y1 - 2011 A1 - Zia Khan A1 - Amini, Sasan A1 - Bloom, Joshua S. A1 - Ruse, Cristian A1 - Caudy, Amy A. A1 - Kruglyak, Leonid A1 - Singh, Mona A1 - Perlman, David H. A1 - Tavazoie, Saeed AB - In quantitative mass spectrometry-based proteomics, the metabolic incorporation of a single source of 15N-labeled nitrogen has many advantages over using stable isotope-labeled amino acids. However, the lack of a robust computational framework for analyzing the resulting spectra has impeded wide use of this approach. We have addressed this challenge by introducing a new computational methodology for analyzing 15N spectra in which quantification is integrated with identification. Application of this method to an Escherichia coli growth transition reveals significant improvement in quantification accuracy over previous methods.PMID: 22182234 VL - 12 SN - 1465-6906 UR - http://genomebiology.com/2011/12/12/R122/abstract CP - 12 ER - TY - CONF T1 - Active scene recognition with vision and language T2 - 2011 IEEE International Conference on Computer Vision (ICCV) Y1 - 2011 A1 - Yu,Xiaodong A1 - Fermüller, Cornelia A1 - Ching Lik Teo A1 - Yezhou Yang A1 - Aloimonos, J. KW - accuracy KW - active scene recognition KW - classification performance KW - Cognition KW - Computer vision KW - Detectors KW - Equations KW - high level knowledge utilization KW - HUMANS KW - image classification KW - inference mechanisms KW - object detectors KW - Object recognition KW - reasoning module KW - sensing process KW - sensory module KW - support vector machines KW - Training AB - This paper presents a novel approach to utilizing high level knowledge for the problem of scene recognition in an active vision framework, which we call active scene recognition. In traditional approaches, high level knowledge is used in the post-processing to combine the outputs of the object detectors to achieve better classification performance. In contrast, the proposed approach employs high level knowledge actively by implementing an interaction between a reasoning module and a sensory module (Figure 1). Following this paradigm, we implemented an active scene recognizer and evaluated it with a dataset of 20 scenes and 100+ objects. We also extended it to the analysis of dynamic scenes for activity recognition with attributes. Experiments demonstrate the effectiveness of the active paradigm in introducing attention and additional constraints into the sensing process. JA - 2011 IEEE International Conference on Computer Vision (ICCV) PB - IEEE SN - 978-1-4577-1101-5 M3 - 10.1109/ICCV.2011.6126320 ER - TY - CONF T1 - Adapting a map query interface for a gesturing touch screen interface T2 - Proceedings of the 20th international conference companion on World wide web Y1 - 2011 A1 - Samet, Hanan A1 - Teitler,Benjamin E. A1 - Adelfio,Marco D. A1 - Lieberman,Michael D. KW - map query interface KW - newsstand KW - touch screen gesturing interface AB - NewsStand is an example application of a general framework that we are developing to enable searching for information using a map query interface, where the information results from monitoring the output of over 8,000 RSS news sources and is available for retrieval within minutes of publication. The user interface of NewsStand was recently adapted so that NewsStand can execute on mobile and tablet devices with a gesturing touch screen interface such as the iPhone, iPod Touch, and iPad. This action led to a discovery of some shortcomings of current mapping APIs as well as devising some interesting new widgets. These issues are discussed, and the realization can be seen by a demo at http://newsstand.umiacs.umd.edu on any of the above Apple devices as well as other devices that support gestures such as an Android phone. JA - Proceedings of the 20th international conference companion on World wide web T3 - WWW '11 PB - ACM CY - New York, NY, USA SN - 978-1-4503-0637-9 UR - http://doi.acm.org/10.1145/1963192.1963303 M3 - 10.1145/1963192.1963303 ER - TY - JOUR T1 - Approximate polytope membership queries JF - Proceedings of 43rd Annual ACM Symposium on Theory of Computing Y1 - 2011 A1 - Arya,S. A1 - da Fonseca,G. D A1 - Mount, Dave AB - We consider an approximate version of a fundamental geo-metric search problem, polytope membership queries. Given a convex polytope P in Rd, presented as the intersection of halfspaces, the objective is to preprocess P so that, given a query point q, it is possible to determine efficiently whether q lies inside P subject to an error bound ε. Previous solutions to this problem were based on straight- forward applications of classic polytope approximation tech- niques by Dudley (1974) and Bentley et al. (1982). The former yields minimum storage, and the latter yields con- stant query time. A space-time tradeoff can be obtained by interpolating between the two. We present the first sig- nificant improvements to this tradeoff. For example, using the same storage as Dudley, we reduce the query time from O(1/ε (d−1)/2 ) to O(1/ε (d−1)/4 ). Our approach is based on a very simple algorithm. Both lower bounds and upper bounds on the performance of the algorithm are presented. To establish the relevance of our results, we introduce a reduction from approximate nearest neighbor searching to approximate polytope membership queries. We show that our tradeoff provides significant improvements to the best known space-time tradeoffs for approximate nearest neigh- bor searching. Furthermore, this is achieved with construc- tions that are much simpler than existing methods ER - TY - CONF T1 - Approximation algorithms for throughput maximization in wireless networks with delay constraints T2 - 2011 Proceedings IEEE INFOCOM Y1 - 2011 A1 - Guanhong Pei A1 - Anil Kumar,V. S A1 - Parthasarathy,S. A1 - Srinivasan, Aravind KW - Approximation algorithms KW - Approximation methods KW - approximation theory KW - Delay KW - delay constraints KW - delays KW - general interference model KW - Interference KW - multihop wireless networks KW - optimisation KW - Optimized production technology KW - radio networks KW - radiofrequency interference KW - target delay bound KW - Throughput KW - throughput maximization KW - Wireless networks AB - We study the problem of throughput maximization in multi-hop wireless networks with end-to-end delay constraints for each session. This problem has received much attention starting with the work of Grossglauser and Tse (2002), and it has been shown that there is a significant tradeoff between the end-to-end delays and the total achievable rate. We develop algorithms to compute such tradeoffs with provable performance guarantees for arbitrary instances, with general interference models. Given a target delay-bound Δ(c) for each session c, our algorithm gives a stable flow vector with a total throughput within a factor of O (logΔm/log log Δm) of the maximum, so that the per-session (end-to-end) delay is O ((logΔm/log log Δm Δ(c))2), where Δm = maxc{Δ(c)}; note that these bounds depend only on the delays, and not on the network size, and this is the first such result, to our knowledge. JA - 2011 Proceedings IEEE INFOCOM PB - IEEE SN - 978-1-4244-9919-9 M3 - 10.1109/INFCOM.2011.5934887 ER - TY - JOUR T1 - Architecting for innovation JF - SIGCOMM Comput. Commun. Rev. Y1 - 2011 A1 - Koponen,Teemu A1 - Shenker,Scott A1 - Balakrishnan,Hari A1 - Feamster, Nick A1 - Ganichev,Igor A1 - Ghodsi,Ali A1 - Godfrey,P. Brighten A1 - McKeown,Nick A1 - Parulkar,Guru A1 - Raghavan,Barath A1 - Rexford,Jennifer A1 - Arianfar,Somaya A1 - Kuptsov,Dmitriy KW - diversity KW - Evolution KW - innovation KW - internet architecture AB - We argue that the biggest problem with the current Internet architecture is not a particular functional deficiency, but its inability to accommodate innovation. To address this problem we propose a minimal architectural "framework" in which comprehensive architectures can reside. The proposed Framework for Internet Innovation (FII) --- which is derived from the simple observation that network interfaces should be extensible and abstract --- allows for a diversity of architectures to coexist, communicate, and evolve. We demonstrate FII's ability to accommodate diversity and evolution with a detailed examination of how information flows through the architecture and with a skeleton implementation of the relevant interfaces. VL - 41 SN - 0146-4833 UR - http://doi.acm.org/10.1145/2002250.2002256 CP - 3 M3 - 10.1145/2002250.2002256 ER - TY - CONF T1 - AVSS 2011 demo session: A large-scale benchmark dataset for event recognition in surveillance video T2 - Advanced Video and Signal-Based Surveillance (AVSS), 2011 8th IEEE International Conference on Y1 - 2011 A1 - Oh,Sangmin A1 - Hoogs,Anthony A1 - Perera,Amitha A1 - Cuntoor,Naresh A1 - Chen,Chia-Chih A1 - Lee,Jong Taek A1 - Mukherjee,Saurajit A1 - Aggarwal, JK A1 - Lee,Hyungtae A1 - Davis, Larry S. A1 - Swears,Eran A1 - Wang,Xiaoyang A1 - Ji,Qiang A1 - Reddy,Kishore A1 - Shah,Mubarak A1 - Vondrick,Carl A1 - Pirsiavash,Hamed A1 - Ramanan,Deva A1 - Yuen,Jenny A1 - Torralba,Antonio A1 - Song,Bi A1 - Fong,Anesco A1 - Roy-Chowdhury,Amit A1 - Desai,Mita AB - We introduce to the surveillance community the VIRAT Video Dataset[1], which is a new large-scale surveillance video dataset designed to assess the performance of event recognition algorithms in realistic scenes1. JA - Advanced Video and Signal-Based Surveillance (AVSS), 2011 8th IEEE International Conference on M3 - 10.1109/AVSS.2011.6027400 ER - TY - JOUR T1 - Bacillus Anthracis Comparative Genome Analysis in Support of the Amerithrax Investigation JF - Proceedings of the National Academy of SciencesPNAS Y1 - 2011 A1 - Rasko,David A A1 - Worsham,Patricia L A1 - Abshire,Terry G A1 - Stanley,Scott T A1 - Bannan,Jason D A1 - Wilson,Mark R A1 - Langham,Richard J A1 - Decker,R. Scott A1 - Jiang,Lingxia A1 - Read,Timothy D. A1 - Phillippy,Adam M A1 - Salzberg,Steven L. A1 - Pop, Mihai A1 - Van Ert,Matthew N A1 - Kenefic,Leo J A1 - Keim,Paul S A1 - Fraser-Liggett,Claire M A1 - Ravel,Jacques AB - Before the anthrax letter attacks of 2001, the developing field of microbial forensics relied on microbial genotyping schemes based on a small portion of a genome sequence. Amerithrax, the investigation into the anthrax letter attacks, applied high-resolution whole-genome sequencing and comparative genomics to identify key genetic features of the letters’ Bacillus anthracis Ames strain. During systematic microbiological analysis of the spore material from the letters, we identified a number of morphological variants based on phenotypic characteristics and the ability to sporulate. The genomes of these morphological variants were sequenced and compared with that of the B. anthracis Ames ancestor, the progenitor of all B. anthracis Ames strains. Through comparative genomics, we identified four distinct loci with verifiable genetic mutations. Three of the four mutations could be directly linked to sporulation pathways in B. anthracis and more specifically to the regulation of the phosphorylation state of Spo0F, a key regulatory protein in the initiation of the sporulation cascade, thus linking phenotype to genotype. None of these variant genotypes were identified in single-colony environmental B. anthracis Ames isolates associated with the investigation. These genotypes were identified only in B. anthracis morphotypes isolated from the letters, indicating that the variants were not prevalent in the environment, not even the environments associated with the investigation. This study demonstrates the forensic value of systematic microbiological analysis combined with whole-genome sequencing and comparative genomics. VL - 108 SN - 0027-8424, 1091-6490 UR - http://www.pnas.org/content/108/12/5027 CP - 12 M3 - 10.1073/pnas.1016657108 ER - TY - CONF T1 - Believe Me—We Can Do This! Annotating Persuasive Acts in Blog Text T2 - Workshops at the Twenty-Fifth AAAI Conference on Artificial Intelligence Y1 - 2011 A1 - Anand,P. A1 - King,J. A1 - Jordan Boyd-Graber A1 - Wagner,E. A1 - Martell,C. A1 - Oard, Douglas A1 - Resnik, Philip JA - Workshops at the Twenty-Fifth AAAI Conference on Artificial Intelligence ER - TY - JOUR T1 - Capacity of wireless networks under SINR interference constraints JF - Wireless Networks Y1 - 2011 A1 - Chafekar,Deepti A1 - Anil Kumar,V. A1 - Marathe,Madhav A1 - Parthasarathy,Srinivasan A1 - Srinivasan, Aravind AB - A fundamental problem in wireless networks is to estimate their throughput capacity—given a set of wireless nodes and a set of connections, what is the maximum rate at which data can be sent on these connections. Most of the research in this direction has focused either on random distributions of points, or has assumed simple graph-based models for wireless interference. In this paper, we study the capacity estimation problem using a realistic Signal to Interference Plus Noise Ratio (SINR) model for interference, on arbitrary wireless networks without any assumptions on node distributions. The problem becomes much more challenging for this setting, because of the non-locality of the SINR model. Recent work by Moscibroda et al. (IEEE INFOCOM 2006, ACM MobiHoc 2006) has shown that the throughput achieved by using SINR models can differ significantly from that obtained by using graph-based models. In this work, we develop polynomial time algorithms to provably approximate the throughput capacity of wireless network under the SINR model. VL - 17 SN - 1022-0038 UR - http://dx.doi.org/10.1007/s11276-011-0367-2 CP - 7 ER - TY - JOUR T1 - Clonal transmission, dual peak, and off-season cholera in Bangladesh JF - Infection Ecology & Epidemiology Y1 - 2011 A1 - Alam,M. A1 - Islam,A. A1 - Bhuiyan,N. A. A1 - Rahim,N. A1 - Hossain,A. A1 - Khan,G. Y. A1 - Ahmed,D. A1 - Watanabe,H. A1 - Izumiya,H. A1 - Faruque,A. S. G. A1 - Rita R Colwell AB - Vibrio cholerae is an estuarine bacterium associated with a single peak of cholera (March–May) in coastal villages of Bangladesh. For an unknown reason, however, cholera occurs in a unique dual peak (March–May and September–November) pattern in the city of Dhaka that is bordered by a heavily polluted freshwater river system and flood embankment. In August 2007, extreme flooding was accompanied by an unusually severe diarrhea outbreak in Dhaka that resulted in a record high illness. This study was aimed to understand the unusual outbreak and if it was related to the circulation of a new V. cholerae clone. Nineteen V. cholerae isolated during the peak of the 2007 outbreak were subjected to extensive phenotypic and molecular analyses, including multi-locus genetic screening by polymerase chain reaction (PCR), sequence-typing of the ctxB gene, and pulsed-field gel electrophoresis (PFGE). Factors associated with the unusual incidence of cholera were determined and analysis of the disease severity was done. Overall, microbiological and molecular data confirmed that the hypervirulent V. cholerae was O1 biotype El Tor (ET) that possessed cholera toxin (CT) of the classical biotype. The PFGE (NotI) and dendrogram clustering confirmed that the strains were clonal and related to the pre-2007 variant ET from Dhaka and Matlab and resembled one of two distinct clones of the variant ET confirmed to be present in the estuarine ecosystem of Bangladesh. Results of the analyses of both diarrheal case data for three consecutive years (2006–2008) and regional hydroclimatology over three decades (1980–2009) clearly indicate that the pattern of cholera occurring in Dhaka, and not seen at other endemic sites, was associated with flood waters transmitting the infectious clone circulating via the fecal-oral route during and between the dual seasonal cholera peaks in Dhaka. Circular river systems and flood embankment likely facilitate transmission of infectious V. cholerae throughout the year that leads to both sudden and off-season outbreaks in the densely populated urban ecosystem of Dhaka. Clonal recycling of hybrid El Tor with increasing virulence in a changing climate and in a region with a growing urban population represents a serious public health concern for Bangladesh. VL - 1 CP - 1 M3 - 10.3402/iee.v1i0.7273 ER - TY - CONF T1 - A Corpus-Guided Framework for Robotic Visual Perception T2 - Workshops at the Twenty-Fifth AAAI Conference on Artificial Intelligence Y1 - 2011 A1 - Teo,C.L. A1 - Yang, Y. A1 - Daumé, Hal A1 - Fermüller, Cornelia A1 - Aloimonos, J. JA - Workshops at the Twenty-Fifth AAAI Conference on Artificial Intelligence ER - TY - BOOK T1 - Decision and Game Theory for Security: Second International Conference, GameSec 2011, College Park, MD, Maryland, USA, November 14-15, 2011, Proceedings Y1 - 2011 A1 - Baras,John S A1 - Katz, Jonathan A1 - Altman,Eitan KW - Business & Economics / Information Management KW - Computers / Hardware / Network Hardware KW - Computers / Information Technology KW - Computers / Programming / Algorithms KW - Computers / Security / General KW - Mathematics / Applied KW - Mathematics / Game Theory KW - Mathematics / General AB - This book constitutes the refereed proceedings of the Second International Conference on Decision and Game Theory for Security, GameSec 2011, held in College Park, Maryland, USA, in November 2011. The 16 revised full papers and 2 plenary keynotes presented were carefully reviewed and selected from numerous submissions. The papers are organized in topical sections on attacks, adversaries, and game theory, wireless adhoc and sensor networks, network games, security insurance, security and trust in social networks and security investments. PB - Springer SN - 9783642252792 ER - TY - JOUR T1 - Design of Revolute Joints for In-Mold Assembly Using Insert Molding JF - Journal of Mechanical Design Y1 - 2011 A1 - Ananthanarayanan,A. A1 - Ehrlich,L. A1 - Desai,J. P. A1 - Gupta,S.K. VL - 133 ER - TY - JOUR T1 - Direct targeting of Sec23a by miR-200s influences cancer cell secretome and promotes metastatic colonization JF - Nature Medicine Y1 - 2011 A1 - Korpal, Manav A1 - Ell, Brian J. A1 - Buffa, Francesca M. A1 - Ibrahim, Toni A1 - Blanco, Mario A. A1 - Celià-Terrassa, Toni A1 - Mercatali, Laura A1 - Zia Khan A1 - Goodarzi, Hani A1 - Hua, Yuling A1 - Wei, Yong A1 - Hu, Guohong A1 - Garcia, Benjamin A. A1 - Ragoussis, Jiannis A1 - Amadori, Dino A1 - Harris, Adrian L. A1 - Kang, Yibin AB - Although the role of miR-200s in regulating E-cadherin expression and epithelial-to-mesenchymal transition is well established, their influence on metastatic colonization remains controversial. Here we have used clinical and experimental models of breast cancer metastasis to discover a pro-metastatic role of miR-200s that goes beyond their regulation of E-cadherin and epithelial phenotype. Overexpression of miR-200s is associated with increased risk of metastasis in breast cancer and promotes metastatic colonization in mouse models, phenotypes that cannot be recapitulated by E-cadherin expression alone. Genomic and proteomic analyses revealed global shifts in gene expression upon miR-200 overexpression toward that of highly metastatic cells. miR-200s promote metastatic colonization partly through direct targeting of Sec23a, which mediates secretion of metastasis-suppressive proteins, including Igfbp4 and Tinagl1, as validated by functional and clinical correlation studies. Overall, these findings suggest a pleiotropic role of miR-200s in promoting metastatic colonization by influencing E-cadherin–dependent epithelial traits and Sec23a-mediated tumor cell secretome.View full text VL - 17 SN - 1078-8956 UR - http://www.nature.com/nm/journal/v17/n9/abs/nm.2401.html CP - 9 J1 - Nat Med ER - TY - CHAP T1 - Distributed Sensing and Processing for Multi-Camera Networks T2 - Distributed Video Sensor NetworksDistributed Video Sensor Networks Y1 - 2011 A1 - Sankaranarayanan,Aswin C. A1 - Chellapa, Rama A1 - Baraniuk,Richard G. ED - Bhanu,Bir ED - Ravishankar,Chinya V. ED - Roy-Chowdhury,Amit K. ED - Aghajan,Hamid ED - Terzopoulos,Demetri AB - Sensor networks with large numbers of cameras are becoming increasingly prevalent in a wide range of applications, including video conferencing, motion capture, surveillance, and clinical diagnostics. In this chapter, we identify some of the fundamental challenges in designing such systems: robust statistical inference, computationally efficiency, and opportunistic and parsimonious sensing. We show that the geometric constraints induced by the imaging process are extremely useful for identifying and designing optimal estimators for object detection and tracking tasks. We also derive pipelined and parallelized implementations of popular tools used for statistical inference in non-linear systems, of which multi-camera systems are examples. Finally, we highlight the use of the emerging theory of compressive sensing in reducing the amount of data sensed and communicated by a camera network. JA - Distributed Video Sensor NetworksDistributed Video Sensor Networks PB - Springer London SN - 978-0-85729-127-1 UR - http://dx.doi.org/10.1007/978-0-85729-127-1_6 ER - TY - CONF T1 - Do You Know Where Your Data Are? Secure Data Capsules for Deployable Data Protection Y1 - 2011 A1 - Maniatis, P. A1 - Akhawe, D. A1 - Fall,K. A1 - Elaine Shi A1 - McCamant, S. A1 - Song,D. UR - http://static.usenix.org/event/hotos11/tech/final_files/ManiatisAkhawe.pdf ER - TY - CONF T1 - Dynamic inference of static types for ruby T2 - Proceedings of the 38th annual ACM SIGPLAN-SIGACT symposium on Principles of programming languages Y1 - 2011 A1 - An,Jong-hoon (David) A1 - Chaudhuri,Avik A1 - Foster, Jeffrey S. A1 - Hicks, Michael W. KW - dynamic languages KW - dynamic type inference KW - ruby KW - static types AB - There have been several efforts to bring static type inference to object-oriented dynamic languages such as Ruby, Python, and Perl. In our experience, however, such type inference systems are extremely difficult to develop, because dynamic languages are typically complex, poorly specified, and include features, such as eval and reflection, that are hard to analyze. In this paper, we introduce constraint-based dynamic type inference, a technique that infers static types based on dynamic program executions. In our approach, we wrap each run-time value to associate it with a type variable, and the wrapper generates constraints on this type variable when the wrapped value is used. This technique avoids many of the often overly conservative approximations of static tools, as constraints are generated based on how values are used during actual program runs. Using wrappers is also easy to implement, since we need only write a constraint resolution algorithm and a transformation to introduce the wrappers. The best part is that we can eat our cake, too: our algorithm will infer sound types as long as it observes every path through each method body---note that the number of such paths may be dramatically smaller than the number of paths through the program as a whole. We have developed Rubydust, an implementation of our algorithm for Ruby. Rubydust takes advantage of Ruby's dynamic features to implement wrappers as a language library. We applied Rubydust to a number of small programs and found it to be both easy to use and useful: Rubydust discovered 1 real type error, and all other inferred types were correct and readable. JA - Proceedings of the 38th annual ACM SIGPLAN-SIGACT symposium on Principles of programming languages T3 - POPL '11 PB - ACM CY - New York, NY, USA SN - 978-1-4503-0490-0 UR - http://doi.acm.org/10.1145/1926385.1926437 M3 - 10.1145/1926385.1926437 ER - TY - JOUR T1 - The Evolution of Network Configuration: A Tale of Two Campuses JF - Networks Y1 - 2011 A1 - Kim,H. A1 - Benson,T. A1 - Akella,A. A1 - Feamster, Nick AB - Studying network configuration evolution can improve our under- standing of the evolving complexity of networks and can be helpful in making network configuration less error-prone. Unfortunately, the nature of changes that operators make to network configuration is poorly understood. Towards improving our understanding, we examine and analyze five years of router, switch, and firewall con- figurations from two large campus networks using the logs from version control systems used to store the configurations. We study how network configuration is distributed across different network operations tasks and how the configuration for each task evolves over time, for different types of devices and for different loca- tions in the network. To understand the trends of how configura- tion evolves over time, we study the extent to which configuration for various tasks are added, modified, or deleted. We also study whether certain devices experience configuration changes more fre- quently than others, as well as whether configuration changes tend to focus on specific portions of the configuration (or on specific tasks). We also investigate when network operators make configu- ration changes of various types. Our results concerning configura- tion changes can help the designers of configuration languages un- derstand which aspects of configuration might be more automated or tested more rigorously and may ultimately help improve config- uration languages. VL - 7 ER - TY - BOOK T1 - GameSec'11: Proceedings of the Second international conference on Decision and Game Theory for Security Y1 - 2011 ED - Baras,John S ED - Katz, Jonathan ED - Altman,Eitan PB - Springer-Verlag CY - Berlin, Heidelberg SN - 978-3-642-25279-2 ER - TY - JOUR T1 - Gene Coexpression Network Topology of Cardiac Development, Hypertrophy, and FailureClinical Perspective JF - Circulation: Cardiovascular GeneticsCirc Cardiovasc Genet Y1 - 2011 A1 - Dewey,Frederick E A1 - Perez,Marco V A1 - Wheeler,Matthew T A1 - Watt,Clifton A1 - Spin,Joshua A1 - Langfelder,Peter A1 - Horvath,Steve A1 - Hannenhalli, Sridhar A1 - Cappola,Thomas P. A1 - Ashley,Euan A KW - fetal KW - Gene expression KW - heart failure KW - hypertrophy KW - myocardium AB - Background— Network analysis techniques allow a more accurate reflection of underlying systems biology to be realized than traditional unidimensional molecular biology approaches. Using gene coexpression network analysis, we define the gene expression network topology of cardiac hypertrophy and failure and the extent of recapitulation of fetal gene expression programs in failing and hypertrophied adult myocardium.Methods and Results— We assembled all myocardial transcript data in the Gene Expression Omnibus (n=1617). Because hierarchical analysis revealed species had primacy over disease clustering, we focused this analysis on the most complete (murine) dataset (n=478). Using gene coexpression network analysis, we derived functional modules, regulatory mediators, and higher-order topological relationships between genes and identified 50 gene coexpression modules in developing myocardium that were not present in normal adult tissue. We found that known gene expression markers of myocardial adaptation were members of upregulated modules but not hub genes. We identified ZIC2 as a novel transcription factor associated with coexpression modules common to developing and failing myocardium. Of 50 fetal gene coexpression modules, 3 (6%) were reproduced in hypertrophied myocardium and 7 (14%) were reproduced in failing myocardium. One fetal module was common to both failing and hypertrophied myocardium. Conclusions— Network modeling allows systems analysis of cardiovascular development and disease. Although we did not find evidence for a global coordinated program of fetal gene expression in adult myocardial adaptation, our analysis revealed specific gene expression modules active during both development and disease and specific candidates for their regulation. VL - 4 SN - 1942-325X, 1942-3268 UR - http://circgenetics.ahajournals.org/content/4/1/26 CP - 1 M3 - 10.1161/CIRCGENETICS.110.941757 ER - TY - CONF T1 - How secure are networked office devices? Y1 - 2011 A1 - Condon,E. A1 - Cummins,E. A1 - Afoulki,Z. A1 - Michel Cukier KW - computer network security KW - data privacy KW - networked office device security KW - privacy risk assessment KW - Risk management KW - security risk assessment KW - STRIDE threat model KW - university network AB - Many office devices have a history of being networked (such as printers) and others without the same past are increasingly becoming networked (such as photocopiers). The modern networked versions of previously non-networked devices have much in common with traditional networked servers in terms of features and functions. While an organization may have policies and procedures for securing traditional network servers, securing networked office devices providing similar services can easily be overlooked. In this paper we present an evaluation of privacy and security risks found when examining over 1,800 networked office devices connected to a large university network. We use the STRIDE threat model to categorize threats and vulnerabilities and then we group the devices according to assessed risk from the perspective of the university. We found that while steps had been taken to secure some devices, many were using default or unsecured configurations. M3 - 10.1109/DSN.2011.5958259 ER - TY - JOUR T1 - The Importance of Chitin in the Marine Environment JF - Marine Biotechnology Y1 - 2011 A1 - Souza,C. P. A1 - Almeida,B. C. A1 - Rita R Colwell A1 - Rivera,I. N. G. AB - Chitin is the most abundant renewable polymer in the oceans and is an important source of carbon and nitrogen for marine organisms. The process of chitin degradation is a key step in the cycling of nutrients in the oceans and chitinolytic bacteria play a significant role in this process. These bacteria are autochthonous to both marine and freshwater ecosystems and produce chitinases that degrade chitin, an insoluble polysaccharide, to a biologically useful form. In this brief review, a description of the structure of chitin and diversity of chitinolytic bacteria in the oceans is provided, in the context of the significance of chitin degradation for marine life. M3 - 10.1007/s10126-011-9388-1 ER - TY - CONF T1 - A large-scale benchmark dataset for event recognition in surveillance video T2 - Computer Vision and Pattern Recognition (CVPR), 2011 IEEE Conference on Y1 - 2011 A1 - Oh,Sangmin A1 - Hoogs, A. A1 - Perera,A. A1 - Cuntoor, N. A1 - Chen,Chia-Chih A1 - Lee,Jong Taek A1 - Mukherjee,S. A1 - Aggarwal, JK A1 - Lee,Hyungtae A1 - Davis, Larry S. A1 - Swears,E. A1 - Wang,Xioyang A1 - Ji,Qiang A1 - Reddy,K. A1 - Shah,M. A1 - Vondrick,C. A1 - Pirsiavash,H. A1 - Ramanan,D. A1 - Yuen,J. A1 - Torralba,A. A1 - Song,Bi A1 - Fong,A. A1 - Roy-Chowdhury, A. A1 - Desai,M. KW - algorithm;evaluation KW - CVER KW - databases; KW - databases;video KW - dataset;moving KW - event KW - metrics;large-scale KW - object KW - recognition KW - recognition;diverse KW - recognition;video KW - scenes;surveillance KW - surveillance;visual KW - tasks;computer KW - tracks;outdoor KW - video KW - video;computer KW - vision;continuous KW - vision;image KW - visual AB - We introduce a new large-scale video dataset designed to assess the performance of diverse visual event recognition algorithms with a focus on continuous visual event recognition (CVER) in outdoor areas with wide coverage. Previous datasets for action recognition are unrealistic for real-world surveillance because they consist of short clips showing one action by one individual [15, 8]. Datasets have been developed for movies [11] and sports [12], but, these actions and scene conditions do not apply effectively to surveillance videos. Our dataset consists of many outdoor scenes with actions occurring naturally by non-actors in continuously captured videos of the real world. The dataset includes large numbers of instances for 23 event types distributed throughout 29 hours of video. This data is accompanied by detailed annotations which include both moving object tracks and event examples, which will provide solid basis for large-scale evaluation. Additionally, we propose different types of evaluation modes for visual recognition tasks and evaluation metrics along with our preliminary experimental results. We believe that this dataset will stimulate diverse aspects of computer vision research and help us to advance the CVER tasks in the years ahead. JA - Computer Vision and Pattern Recognition (CVPR), 2011 IEEE Conference on M3 - 10.1109/CVPR.2011.5995586 ER - TY - CHAP T1 - A Longitudinal Study of Pressure Sensing to Infer Real-World Water Usage Events in the Home T2 - Pervasive ComputingPervasive Computing Y1 - 2011 A1 - Jon Froehlich A1 - Larson,Eric A1 - Saba,Elliot A1 - Campbell,Tim A1 - Atlas,Les A1 - Fogarty,James A1 - Patel,Shwetak ED - Lyons,Kent ED - Hightower,Jeffrey ED - Huang,Elaine AB - We present the first longitudinal study of pressure sensing to infer real-world water usage events in the home (e.g., dishwasher, upstairs bathroom sink, downstairs toilet). In order to study the pressure-based approach out in the wild , we deployed a ground truth sensor network for five weeks in three homes and two apartments that directly monitored valve-level water usage by fixtures and appliances . We use this data to, first, demonstrate the practical challenges in constructing water usage activity inference algorithms and, second, to inform the design of a new probabilistic-based classification approach. Inspired by algorithms in speech recognition, our novel Bayesian approach incorporates template matching, a language model, grammar, and prior probabilities. We show that with a single pressure sensor, our probabilistic algorithm can classify real-world water usage at the fixture level with 90% accuracy and at the fixturecategory level with 96% accuracy. With two pressure sensors, these accuracies increase to 94% and 98%. Finally, we show how our new approach can be trained with fewer examples than a strict template-matching approach alone. JA - Pervasive ComputingPervasive Computing T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 6696 SN - 978-3-642-21725-8 UR - http://dx.doi.org/10.1007/978-3-642-21726-5_4 ER - TY - CHAP T1 - A Longitudinal Study of Pressure Sensing to Infer Real-World Water Usage Events in the Home T2 - Pervasive Computing Y1 - 2011 A1 - Jon Froehlich A1 - Larson,Eric A1 - Saba,Elliot A1 - Campbell,Tim A1 - Atlas,Les A1 - Fogarty,James A1 - Patel,Shwetak ED - Lyons,Kent ED - Hightower,Jeffrey ED - Huang,Elaine AB - We present the first longitudinal study of pressure sensing to infer real-world water usage events in the home (e.g., dishwasher, upstairs bathroom sink, downstairs toilet). In order to study the pressure-based approach out in the wild , we deployed a ground truth sensor network for five weeks in three homes and two apartments that directly monitored valve-level water usage by fixtures and appliances . We use this data to, first, demonstrate the practical challenges in constructing water usage activity inference algorithms and, second, to inform the design of a new probabilistic-based classification approach. Inspired by algorithms in speech recognition, our novel Bayesian approach incorporates template matching, a language model, grammar, and prior probabilities. We show that with a single pressure sensor, our probabilistic algorithm can classify real-world water usage at the fixture level with 90% accuracy and at the fixturecategory level with 96% accuracy. With two pressure sensors, these accuracies increase to 94% and 98%. Finally, we show how our new approach can be trained with fewer examples than a strict template-matching approach alone. JA - Pervasive Computing T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 6696 SN - 978-3-642-21725-8 UR - http://dx.doi.org/10.1007/978-3-642-21726-5_4 ER - TY - JOUR T1 - Maximum bipartite flow in networks with adaptive channel width JF - Theoretical Computer Science Y1 - 2011 A1 - Azar,Yossi A1 - Mądry,Aleksander A1 - Moscibroda,Thomas A1 - Panigrahi,Debmalya A1 - Srinivasan, Aravind KW - Adaptive channel width KW - graph algorithm KW - Linear program rounding KW - Maximum flow KW - Wireless networks AB - Traditionally, network optimization problems assume that each link in the network has a fixed capacity. Recent research in wireless networking has shown that it is possible to design networks where the capacity of the links can be changed adaptively to suit the needs of specific applications. In particular, one gets a choice of having a few high capacity outgoing links or many low capacity ones at any node of the network. This motivates us to have a re-look at classical network optimization problems and design algorithms to solve them in this new framework. In particular, we consider the problem of maximum bipartite flow, which has been studied extensively in the fixed-capacity network model. One of the motivations for studying this problem arises from the need to maximize the throughput of an infrastructure wireless network comprising base-stations (one set of vertices in the bipartition) and clients (the other set of vertices in the bipartition). We show that this problem has a significantly different combinatorial structure in this new network model from the fixed-capacity one. While there are several polynomial time algorithms for the maximum bipartite flow problem in traditional networks, we show that the problem is NP-hard in the new model. In fact, our proof extends to showing that the problem is APX-hard. We complement our lower bound by giving two algorithms for solving the problem approximately. The first algorithm is deterministic and achieves an approximation factor of O ( log N ) , where N is the number of nodes in the network, while the second algorithm is randomized and achieves an approximation factor of e e − 1 . VL - 412 SN - 0304-3975 UR - http://www.sciencedirect.com/science/article/pii/S0304397510005852 CP - 24 M3 - 10.1016/j.tcs.2010.10.023 ER - TY - JOUR T1 - Metagenomic 16S rDNA Targeted PCR-DGGE in Determining Bacterial Diversity in Aquatic Ecosystem JF - Bangladesh Journal of Microbiology Y1 - 2011 A1 - Hasan,Nur A. A1 - Chowdhury,W Bari A1 - Rahim,Niaz A1 - Sultana,Marzia A1 - Shabnam,S Antara A1 - Mai,Volker A1 - Ali,Afsar A1 - Morris,Glen J A1 - Sack,R. Bradley A1 - Huq,Anwar A1 - Rita R Colwell A1 - Endtz,Hubert Ph A1 - Cravioto,Alejandro A1 - Alam,Munirul AB - Bacterial numbers in surface water samples, collected randomly from six different water bodies, were estimated by acridine orange direct counting (AODC) and conventional culture-based heterotrophic plate counting (HPC). Bacterial genomic DNA was prepared from water samples by employing methods used for stool samples, including the population dynamics, were determined by primer extension of the 16S rDNA (V6/V8 region) using polymerase chain reaction (PCR), followed by denaturing gradient gel electrophoresis (DGGE), a metagenomic tool that is capable of separating unrelated DNAs based on the differences in their sequences and GC contents. The bacterial numbers in water samples ranged from 103 – 106 CFU/ mL for HPC and 104 – 107 cells/ mL for AODC, showing that a great majority of bacteria prevail as uncultivable which do not respond to culture methods that are used widely for tracking bacterial pathogens. The acridine orange-stained bacteria varied in sizes and shapes, and appeared either as planktonic (solitary) cells or as clusters of biofilms, showing the presence of diverse community under the epifluorescence microscope. The DGGE of the ca. 457 bp amplicons, as confirmed by agarose gel electrophoresis, produced bands that ranged in intensities and numbers from 18 to 31, with each band possibly indicating the presence of one or more closely related bacterial species. The enrichment of pathogenic bacteria in the aquatic ecosystem is known to precede the seasonal diarrhoeal outbreaks; therefore, bacterial community dynamics determined by Metagenomic 16S PCR-DGGE during pre-epidemic enrichment appears promising in predicting the upcoming diarrheal outbreaks. VL - 27 SN - 1011-9981 UR - http://www.banglajol.info/bd/index.php/BJM/article/view/9171 CP - 2 M3 - 10.3329/bjm.v27i2.9171 ER - TY - JOUR T1 - Next Generation Sequence Assembly with AMOS JF - Current Protocols in Bioinformatics Y1 - 2011 A1 - Treangen, T.J. A1 - Sommer, D.D. A1 - Angly, F.E. A1 - Koren, S. A1 - Pop, Mihai VL - 11 ER - TY - JOUR T1 - Occurrence of Vibrio cholerae in Municipal and Natural Waters and Incidence of Cholera in Azerbaijan JF - EcoHealth Y1 - 2011 A1 - Gurbanov, Shair A1 - Akhmadov, Rashid A1 - Shamkhalova, Gulnara A1 - Akhmadova, Sevinj A1 - Haley, Bradd J. A1 - Rita R Colwell A1 - Huq, Anwar AB - Cholera, a waterborne disease caused by Vibrio cholerae, is an autochthonous member of the aquatic environment and predominantly reported from developing countries. Technical reports and proceedings were reviewed to determine the relationship between occurrence of V. cholerae in natural waters, including sources of municipal water, and cases of cholera in Azerbaijan. Water samples collected from different environmental sources from 1970 to 1998 were tested for V. cholerae and 0.73% (864/117,893) were positive. The results showed that in April of each year, when the air temperature rose by approximately 5°C, V. cholerae could be isolated. With each increase in air temperature, 6–8 weeks after, impact on cases of cholera was recorded. The incidence of cholera peaked when the air temperature reached >25°C during the month of September. It is concluded that a distinct seasonality in cholera incidence exists in Azerbaijan, with increased occurrence during warmer months. UR - http://link.springer.com/10.1007/s10393-012-0756-8 CP - 4 J1 - EcoHealth M3 - 10.1007/s10393-012-0756-8 ER - TY - JOUR T1 - Role of Zooplankton Diversity in Vibrio Cholerae Population Dynamics and in the Incidence of Cholera in the Bangladesh Sundarbans JF - Applied and Environmental Microbiology Y1 - 2011 A1 - De Magny,Guillaume Constantin A1 - Mozumder,Pronob K. A1 - Grim,Christopher J. A1 - Hasan,Nur A. A1 - Naser,M. Niamul A1 - Alam,Munirul A1 - Sack,R. Bradley A1 - Huq,Anwar A1 - Rita R Colwell AB - Vibrio cholerae, a bacterium autochthonous to the aquatic environment, is the causative agent of cholera, a severe watery, life-threatening diarrheal disease occurring predominantly in developing countries. V. cholerae, including both serogroups O1 and O139, is found in association with crustacean zooplankton, mainly copepods, and notably in ponds, rivers, and estuarine systems globally. The incidence of cholera and occurrence of pathogenic V. cholerae strains with zooplankton were studied in two areas of Bangladesh: Bakerganj and Mathbaria. Chitinous zooplankton communities of several bodies of water were analyzed in order to understand the interaction of the zooplankton population composition with the population dynamics of pathogenic V. cholerae and incidence of cholera. Two dominant zooplankton groups were found to be consistently associated with detection of V. cholerae and/or occurrence of cholera cases, namely, rotifers and cladocerans, in addition to copepods. Local differences indicate there are subtle ecological factors that can influence interactions between V. cholerae, its plankton hosts, and the incidence of cholera. VL - 77 SN - 0099-2240, 1098-5336 UR - http://aem.asm.org/content/77/17/6125 CP - 17 M3 - 10.1128/AEM.01472-10 ER - TY - CONF T1 - Segmentation of Handwritten Textlines in Presence of Touching Components T2 - Intl. Conf. on Document Analysis and Recognition (ICDAR 11) Y1 - 2011 A1 - Kumar,Jayant A1 - Kang,Le A1 - David Doermann A1 - Abd-Almageed, Wael AB - This paper presents an approach to textline extraction in handwritten document images which combines local and global techniques. We propose a graph-based technique to detect touching and proximity errors that are common with handwritten text lines. In a refinement step, we use Expectation-Maximization (EM) to iteratively split the error segments to obtain correct text-lines. We show improvement in accuracies using our correction method on datasets of Arabic document images. Results on a set of artificially generated proximity images show that the method is effective for handling touching errors in handwritten document images. JA - Intl. Conf. on Document Analysis and Recognition (ICDAR 11) ER - TY - CONF T1 - Shape Codebook based Handwritten and Machine Printed Text Zone Extraction T2 - Document Recognition and Retrieval Y1 - 2011 A1 - Kumar,Jayant A1 - Prasad,Rohit A1 - Cao,Huiagu A1 - Abd-Almageed, Wael A1 - David Doermann A1 - Natarajan,Prem AB - We present a novel method for extracting handwritten and printed text zones from noisy document images with mixed content. We use Triple-Adjacent-Segment (TAS) based features which encode local shape characteristics of text in a consistent manner. We first construct two different codebooks of the shape features extracted from a set of handwritten and printed text documents. In the next step, we compute the normalized histogram of codewords for each segmented zone and use it to train Support Vector Machine (SVM) classifier. Due to a codebook based approach, our method is robust to the background noise present in the image. The TAS features used are invariant to translation, scale and rotation of text. In our experimental results, we show that a pixel-weighted zone classification accuracy of 98% can be achieved for noisy Arabic documents. Further, we demonstrate the effectiveness of our method for document page classification and show that a high precision can be achieved for machine printed documents. The proposed method is robust to the size of zones, which may contain text content at word, line or paragraph level. JA - Document Recognition and Retrieval CY - San Francisco ER - TY - JOUR T1 - Silhouette-based gesture and action recognition via modeling trajectories on Riemannian shape manifolds JF - Computer Vision and Image Understanding Y1 - 2011 A1 - Abdelkader,Mohamed F. A1 - Abd-Almageed, Wael A1 - Srivastava,Anuj A1 - Chellapa, Rama KW - Action recognition KW - Gesture recognition KW - Riemannian manifolds KW - Shape space KW - Silhouette-based approaches AB - This paper addresses the problem of recognizing human gestures from videos using models that are built from the Riemannian geometry of shape spaces. We represent a human gesture as a temporal sequence of human poses, each characterized by a contour of the associated human silhouette. The shape of a contour is viewed as a point on the shape space of closed curves and, hence, each gesture is characterized and modeled as a trajectory on this shape space. We propose two approaches for modeling these trajectories. In the first template-based approach, we use dynamic time warping (DTW) to align the different trajectories using elastic geodesic distances on the shape space. The gesture templates are then calculated by averaging the aligned trajectories. In the second approach, we use a graphical model approach similar to an exemplar-based hidden Markov model, where we cluster the gesture shapes on the shape space, and build non-parametric statistical models to capture the variations within each cluster. We model each gesture as a Markov model of transitions between these clusters. To evaluate the proposed approaches, an extensive set of experiments was performed using two different data sets representing gesture and action recognition applications. The proposed approaches not only are successfully able to represent the shape and dynamics of the different classes for recognition, but are also robust against some errors resulting from segmentation and background subtraction. VL - 115 SN - 1077-3142 UR - http://www.sciencedirect.com/science/article/pii/S1077314210002377 CP - 3 M3 - 16/j.cviu.2010.10.006 ER - TY - CONF T1 - Stroke-like Pattern Noise Removal in Binary Document Images T2 - International Conference on Document Analysis and Recognition Y1 - 2011 A1 - Agrawal,Mudit A1 - David Doermann AB - This paper presents a two-phased stroke-like pattern noise (SPN) removal algorithm for binary document images. The proposed approach aims at understanding script-independent prominent text component features using supervised classification as a first step. It then uses their cohesiveness and stroke-width properties to filter and associate smaller text components with them using an unsupervised classification technique. In order to perform text extraction, and hence noise removal, at diacritic-level, this divide-and-conquer technique does not assume the availability of accurate and large amounts of ground-truth data at component-level for training purposes. The method was tested on a collection of degraded and noisy, machine-printed and handwritten binary Arabic text documents. Results show pixel-level precision and recall of 98% and 97% respectively. JA - International Conference on Document Analysis and Recognition ER - TY - JOUR T1 - A task taxonomy of network evolution analysis JF - University of Maryland, Human-Computer Interaction Lab Tech Report HCIL-2011-09 Y1 - 2011 A1 - Ahn,JW A1 - Plaisant, Catherine A1 - Shneiderman, Ben AB - Visualization is a useful tool for understanding the nature of networks. The recent growth of social media requires morepowerful visualization techniques beyond static network diagrams. One of the most important challenges is the visualization of temporal network evolution. In order to provide strong temporal visualization methods, we need to understand what tasks users accomplish. This study provides a taxonomy of the temporal network visualization tasks. We identify (1) the entities, (2) the properties to be visualized, and (3) the hierarchy of temporal features, which were extracted by surveying existing temporal network visualization systems. By building and examining the task taxonomy, we report which tasks have been covered so far and suggest additions for designing the future visualizations. We also present example visualizations constructed using the task taxonomy for a social networking site in order to validate the quality of the taxonomy. ER - TY - CHAP T1 - Temporal Visualization of Social Network Dynamics: Prototypes for Nation of Neighbors T2 - Social Computing, Behavioral-Cultural Modeling and PredictionSocial Computing, Behavioral-Cultural Modeling and Prediction Y1 - 2011 A1 - Ahn,Jae-wook A1 - Taieb-Maimon,Meirav A1 - Sopan,Awalin A1 - Plaisant, Catherine A1 - Shneiderman, Ben ED - Salerno,John ED - Yang,Shanchieh ED - Nau, Dana S. ED - Chai,Sun-Ki AB - Information visualization is a powerful tool for analyzing the dynamic nature of social communities. Using Nation of Neighbors community network as a testbed, we propose five principles of implementing temporal visualizations for social networks and present two research prototypes: NodeXL and TempoVis. Three different states are defined in order to visualize the temporal changes of social networks. We designed the prototypes to show the benefits of the proposed ideas by letting users interactively explore temporal changes of social networks. JA - Social Computing, Behavioral-Cultural Modeling and PredictionSocial Computing, Behavioral-Cultural Modeling and Prediction T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 6589 SN - 978-3-642-19655-3 UR - http://dx.doi.org/10.1007/978-3-642-19656-0_43 ER - TY - JOUR T1 - Threat-Aware Clustering in Wireless Sensor Networks JF - IFIP Advances in Information and Communication Technology (AICT) Y1 - 2011 A1 - Abd-Almageed, Wael A1 - Blace,R.E. A1 - Eltoweissy,M. VL - 264 CP - 264 ER - TY - JOUR T1 - Using Variational Inference and MapReduce to Scale Topic Modeling JF - arXiv:1107.3765 Y1 - 2011 A1 - Zhai,Ke A1 - Jordan Boyd-Graber A1 - Asadi,Nima KW - Computer Science - Artificial Intelligence KW - Computer Science - Distributed, Parallel, and Cluster Computing AB - Latent Dirichlet Allocation (LDA) is a popular topic modeling technique for exploring document collections. Because of the increasing prevalence of large datasets, there is a need to improve the scalability of inference of LDA. In this paper, we propose a technique called ~\emph{MapReduce LDA} (Mr. LDA) to accommodate very large corpus collections in the MapReduce framework. In contrast to other techniques to scale inference for LDA, which use Gibbs sampling, we use variational inference. Our solution efficiently distributes computation and is relatively simple to implement. More importantly, this variational implementation, unlike highly tuned and specialized implementations, is easily extensible. We demonstrate two extensions of the model possible with this scalable framework: informed priors to guide topic discovery and modeling topics from a multilingual corpus. UR - http://arxiv.org/abs/1107.3765 ER - TY - CONF T1 - Visual Analysis of Temporal Trends in Social Networks Using Edge Color Coding and Metric Timelines T2 - Privacy, Security, Risk and Trust (PASSAT), 2011 IEEE Third International Conference on and 2011 IEEE Third International Confernece on Social Computing (SocialCom) Y1 - 2011 A1 - Khurana,U. A1 - Nguyen,Viet-An A1 - Hsueh-Chien Cheng A1 - Ahn,Jae-wook A1 - Chen,Xi A1 - Shneiderman, Ben KW - Color KW - computer scientists KW - data analysts KW - data visualisation KW - Data visualization KW - dynamic social network KW - dynamic timeslider KW - edge color coding KW - excel sheet KW - Image coding KW - image colour analysis KW - Layout KW - measurement KW - metric timelines KW - Microsoft excel KW - multiple graph metrics KW - Net EvViz KW - network components KW - network layout KW - network visualization tool KW - NodeXL template KW - social networking (online) KW - temporal trends KW - Twitter KW - Visualization AB - We present Net EvViz, a visualization tool for analysis and exploration of a dynamic social network. There are plenty of visual social network analysis tools but few provide features for visualization of dynamically changing networks featuring the addition or deletion of nodes or edges. Our tool extends the code base of the Node XL template for Microsoft Excel, a popular network visualization tool. The key features of this work are (1) The ability of the user to specify and edit temporal annotations to the network components in an Excel sheet, (2) See the dynamics of the network with multiple graph metrics plotted over the time span of the graph, called the Timeline, and (3) Temporal exploration of the network layout using an edge coloring scheme and a dynamic Time slider. The objectives of the new features presented in this paper are to let the data analysts, computer scientists and others to observe the dynamics or evolution in a network interactively. We presented Net EvViz to five users of Node XL and received positive responses. JA - Privacy, Security, Risk and Trust (PASSAT), 2011 IEEE Third International Conference on and 2011 IEEE Third International Confernece on Social Computing (SocialCom) PB - IEEE SN - 978-1-4577-1931-8 M3 - 10.1109/PASSAT/SocialCom.2011.212 ER - TY - JOUR T1 - Visual Exploration across Biomedical Databases JF - IEEE/ACM Transactions on Computational Biology and Bioinformatics Y1 - 2011 A1 - Lieberman,M.D. A1 - Taheri, S. A1 - Guo,Huimin A1 - Mirrashed,F. A1 - Yahav,I. A1 - Aris,A. A1 - Shneiderman, Ben KW - Bioinformatics KW - Biomedical computing KW - biomedical databases KW - cross-database exploration KW - Data exploration and discovery KW - Data visualization KW - database management systems KW - Databases, Factual KW - DNA KW - graph theory KW - Information Storage and Retrieval KW - information visualization. KW - Keyword search KW - medical computing KW - natural language processing KW - Proteins KW - semantic networks KW - semantics KW - sequences KW - text mining KW - User-Computer Interface KW - user-defined semantics KW - visual databases AB - Though biomedical research often draws on knowledge from a wide variety of fields, few visualization methods for biomedical data incorporate meaningful cross-database exploration. A new approach is offered for visualizing and exploring a query-based subset of multiple heterogeneous biomedical databases. Databases are modeled as an entity-relation graph containing nodes (database records) and links (relationships between records). Users specify a keyword search string to retrieve an initial set of nodes, and then explore intra- and interdatabase links. Results are visualized with user-defined semantic substrates to take advantage of the rich set of attributes usually present in biomedical data. Comments from domain experts indicate that this visualization method is potentially advantageous for biomedical knowledge exploration. VL - 8 SN - 1545-5963 CP - 2 M3 - 10.1109/TCBB.2010.1 ER - TY - CONF T1 - Visual Scene Interpretation as a Dialogue between Vision and Language T2 - Workshops at the Twenty-Fifth AAAI Conference on Artificial Intelligence Y1 - 2011 A1 - Yu,Xiaodong A1 - Fermüller, Cornelia A1 - Aloimonos, J. AB - We present a framework for semantic visual scene interpretation in a system with vision and language. In this framework the system consists of two modules, a language module and a vision module that communicate with each other in a form of a dialogue to actively interpret the scene. The language module is responsible for obtaining domain knowledge from linguistic resources and reasoning on the basis of this knowledge and the visual input. It iteratively creates questions that amount to an attention mechanism for the vision module which in turn shifts its focus to selected parts of the scene and applies selective segmentation and feature extraction. As a formalism for optimizing this dialogue we use information theory. We demonstrate the framework on the problem of recognizing a static scene from its objects and show preliminary results for the problem of human activity recognition from video. Experiments demonstrate the effectiveness of the active paradigm in introducing attention and additional constraints into the sensing process. JA - Workshops at the Twenty-Fifth AAAI Conference on Artificial Intelligence UR - http://www.aaai.org/ocs/index.php/WS/AAAIW11/paper/viewPaper/3989 ER - TY - JOUR T1 - Warming Oceans, Phytoplankton, and River Discharge: Implications for Cholera Outbreaks JF - The American Journal of Tropical Medicine and Hygiene Y1 - 2011 A1 - Jutla,Antarpreet S. A1 - Akanda,Ali S. A1 - Griffiths,Jeffrey K. A1 - Rita R Colwell A1 - Islam,Shafiqul AB - Phytoplankton abundance is inversely related to sea surface temperature (SST). However, a positive relationship is observed between SST and phytoplankton abundance in coastal waters of Bay of Bengal. This has led to an assertion that in a warming climate, rise in SST may increase phytoplankton blooms and, therefore, cholera outbreaks. Here, we explain why a positive SST-phytoplankton relationship exists in the Bay of Bengal and the implications of such a relationship on cholera dynamics. We found clear evidence of two independent physical drivers for phytoplankton abundance. The first one is the widely accepted phytoplankton blooming produced by the upwelling of cold, nutrient-rich deep ocean waters. The second, which explains the Bay of Bengal findings, is coastal phytoplankton blooming during high river discharges with terrestrial nutrients. Causal mechanisms should be understood when associating SST with phytoplankton and subsequent cholera outbreaks in regions where freshwater discharge are a predominant mechanism for phytoplankton production. VL - 85 SN - 0002-9637, UR - http://www.ajtmh.org/content/85/2/303 CP - 2 M3 - 10.4269/ajtmh.2011.11-0181 ER - TY - CONF T1 - When does simulated data match real data? T2 - Proceedings of the 13th annual conference companion on Genetic and evolutionary computation Y1 - 2011 A1 - Stonedahl,Forrest A1 - Anderson,David A1 - Rand, William KW - Agent-based modeling KW - business KW - Calibration KW - Genetic algorithms KW - information search KW - network analysis AB - Agent-based models can replicate real-world patterns, but finding parameters that achieve the best match can be difficult. To validate a model, a real-world dataset is often divided into a training set (to calibrate the parameters) and a test set (to validate the calibrated model). The difference between the training and test data and the simulated data is determined using an error measure. In the context of evolutionary computation techniques, the error measure also serves as a fitness function, and thus affects evolutionary search dynamics. We survey the effect of five different error measures on both a toy problem and a real world problem of matching a model to empirical online news consumption behavior. We use each error measure separately for calibration on the training dataset, and then examine the results of all five error measures on both the training and testing datasets. We show that certain error measures sometimes serve as better fitness functions than others, and in fact using one error measure may result in better calibration (on a different measure) than using the different measure directly. For the toy problem, the Pearson's correlation measure dominated all other measures, but no single error measure was Pareto dominant for the real world problem. JA - Proceedings of the 13th annual conference companion on Genetic and evolutionary computation T3 - GECCO '11 PB - ACM CY - New York, NY, USA SN - 978-1-4503-0690-4 UR - http://doi.acm.org/10.1145/2001858.2001988 M3 - 10.1145/2001858.2001988 ER - TY - JOUR T1 - Achieving anonymity via clustering JF - ACM Trans. Algorithms Y1 - 2010 A1 - Aggarwal,Gagan A1 - Panigrahy,Rina A1 - Feder,Tomás A1 - Thomas,Dilys A1 - Kenthapadi,Krishnaram A1 - Khuller, Samir A1 - Zhu,An KW - anonymity KW - Approximation algorithms KW - clustering KW - privacy AB - Publishing data for analysis from a table containing personal records, while maintaining individual privacy, is a problem of increasing importance today. The traditional approach of deidentifying records is to remove identifying fields such as social security number, name, etc. However, recent research has shown that a large fraction of the U.S. population can be identified using nonkey attributes (called quasi-identifiers) such as date of birth, gender, and zip code. The k-anonymity model protects privacy via requiring that nonkey attributes that leak information are suppressed or generalized so that, for every record in the modified table, there are at least k−1 other records having exactly the same values for quasi-identifiers. We propose a new method for anonymizing data records, where quasi-identifiers of data records are first clustered and then cluster centers are published. To ensure privacy of the data records, we impose the constraint that each cluster must contain no fewer than a prespecified number of data records. This technique is more general since we have a much larger choice for cluster centers than k-anonymity. In many cases, it lets us release a lot more information without compromising privacy. We also provide constant factor approximation algorithms to come up with such a clustering. This is the first set of algorithms for the anonymization problem where the performance is independent of the anonymity parameter k. We further observe that a few outlier points can significantly increase the cost of anonymization. Hence, we extend our algorithms to allow an ε fraction of points to remain unclustered, that is, deleted from the anonymized publication. Thus, by not releasing a small fraction of the database records, we can ensure that the data published for analysis has less distortion and hence is more useful. Our approximation algorithms for new clustering objectives are of independent interest and could be applicable in other clustering scenarios as well. VL - 6 SN - 1549-6325 UR - http://doi.acm.org/10.1145/1798596.1798602 CP - 3 M3 - 10.1145/1798596.1798602 ER - TY - JOUR T1 - Building a dynamic reputation system for DNS JF - 19th Usenix Security Symposium Y1 - 2010 A1 - Antonakakis,M. A1 - Perdisci,R. A1 - Dagon,D. A1 - Lee,W. A1 - Feamster, Nick AB - The Domain Name System (DNS) is an essential protocolused by both legitimate Internet applications and cyber at- tacks. For example, botnets rely on DNS to support agile com- mand and control infrastructures. An effective way to disrupt these attacks is to place malicious domains on a “blocklist” (or “blacklist”) or to add a filtering rule in a firewall or net- work intrusion detection system. To evade such security coun- termeasures, attackers have used DNS agility, e.g., by using new domains daily to evade static blacklists and firewalls. In this paper we propose Notos, a dynamic reputation system for DNS. The premise of this system is that malicious, agile use of DNS has unique characteristics and can be distinguished from legitimate, professionally provisioned DNS services. No- tos uses passive DNS query data and analyzes the network and zone features of domains. It builds models of known legit- imate domains and malicious domains, and uses these models to compute a reputation score for a new domain indicative of whether the domain is malicious or legitimate. We have eval- uated Notos in a large ISP’s network with DNS traffic from 1.4 million users. Our results show that Notos can identify malicious domains with high accuracy (true positive rate of 96.8%) and low false positive rate (0.38%), and can identify these domains weeks or even months before they appear in public blacklists. ER - TY - JOUR T1 - Building a fast, virtualized data plane with programmable hardware JF - SIGCOMM Comput. Commun. Rev. Y1 - 2010 A1 - Anwer,Muhammad Bilal A1 - Feamster, Nick KW - netfpga KW - network virtualization AB - Network virtualization allows many networks to share the same underlying physical topology; this technology has offered promise both for experimentation and for hosting multiple networks on a single shared physical infrastructure. Much attention has focused on virtualizing the network control plane, but, ultimately, a limiting factor in the deployment of these virtual networks is data-plane performance: Virtual networks must ultimately forward packets at rates that are comparable to native, hardware-based approaches. Aside from proprietary solutions from vendors, hardware support for virtualized data planes is limited. The advent of open, programmable network hardware promises flexibility, speed, and resource isolation, but, unfortunately, hardware does not naturally lend itself to virtualization. We leverage emerging trends in programmable hardware to design a flexible, hardware-based data plane for virtual networks. We present the design, implementation, and preliminary evaluation of this hardware-based data plane and show how the proposed design can support many virtual networks without compromising performance or isolation. VL - 40 SN - 0146-4833 UR - http://doi.acm.org/10.1145/1672308.1672323 CP - 1 M3 - 10.1145/1672308.1672323 ER - TY - JOUR T1 - Comparative Genomics of Clinical and Environmental Vibrio Mimicus JF - Proceedings of the National Academy of SciencesPNAS Y1 - 2010 A1 - Hasan,Nur A. A1 - Grim,Christopher J. A1 - Haley,Bradd J. A1 - Jongsik Chun A1 - Alam,Munirul A1 - Taviani,Elisa A1 - Mozammel Hoq A1 - Munk,A. Christine A1 - Rita R Colwell AB - Whether Vibrio mimicus is a variant of Vibrio cholerae or a separate species has been the subject of taxonomic controversy. A genomic analysis was undertaken to resolve the issue. The genomes of V. mimicus MB451, a clinical isolate, and VM223, an environmental isolate, comprise ca. 4,347,971 and 4,313,453 bp and encode 3,802 and 3,290 ORFs, respectively. As in other vibrios, chromosome I (C-I) predominantly contains genes necessary for growth and viability, whereas chromosome II (C-II) bears genes for adaptation to environmental change. C-I harbors many virulence genes, including some not previously reported in V. mimicus, such as mannose-sensitive hemagglutinin (MSHA), and enterotoxigenic hemolysin (HlyA); C-II encodes a variant of Vibrio pathogenicity island 2 (VPI-2), and Vibrio seventh pandemic island II (VSP-II) cluster of genes. Extensive genomic rearrangement in C-II indicates it is a hot spot for evolution and genesis of speciation for the genus Vibrio. The number of virulence regions discovered in this study (VSP-II, MSHA, HlyA, type IV pilin, PilE, and integron integrase, IntI4) with no notable difference in potential virulence genes between clinical and environmental strains suggests these genes also may play a role in the environment and that pathogenic strains may arise in the environment. Significant genome synteny with prototypic pre-seventh pandemic strains of V. cholerae was observed, and the results of phylogenetic analysis support the hypothesis that, in the course of evolution, V. mimicus and V. cholerae diverged from a common ancestor with a prototypic sixth pandemic genomic backbone. VL - 107 SN - 0027-8424, 1091-6490 UR - http://www.pnas.org/content/107/49/21134 CP - 49 M3 - 10.1073/pnas.1013825107 ER - TY - CONF T1 - Context-Aware and Content-Based Dynamic Voronoi Page Segmentation T2 - The Nineth IAPRInternational Workshop on Document Analysis Systems Y1 - 2010 A1 - Agrawal,Mudit A1 - David Doermann AB - This paper presents a dynamic approach to document page segmentation based on inter-component relationships, local patterns and context features. State-of-the art page segmentation algorithms segment zones based on local properties of neighboring connected components such as distance and orientation, and do not typically consider additional properties other than size. Our proposed approach uses a contextually aware and dynamically adaptive page segmentation scheme. The page is first over-segmented using a dynamically adaptive scheme of separation features based on [2] and adapted from [13]. A decision to form zones is then based on the context built from these local separation features and high-level content features. Zone-based evaluation was performed on sets of printed and handwritten documents in English and Arabic scripts with multiple font types, sizes and we achieved an increase of 15% over the accuracy reported in [2]. JA - The Nineth IAPRInternational Workshop on Document Analysis Systems ER - TY - CONF T1 - Deliberate Interactions: Characterizing Technology Use in Nairobi, Kenya T2 - SIGCHI '10 Y1 - 2010 A1 - Wyche, Susan P. A1 - Smyth, Thomas N. A1 - Marshini Chetty A1 - Aoki, Paul M. A1 - Grinter, Rebecca E. KW - everyday technology KW - hci4d KW - Kenya KW - urban computing AB - We present results from a qualitative study examining how professionals living and working in Nairobi, Kenya regularly use ICT in their everyday lives. There are two contributions of this work for the HCI community. First, we provide empirical evidence demonstrating constraints our participants encountered when using technology in an infrastructure-poor setting. These constraints are limited bandwidth, high costs, differing perceptions of responsiveness, and threats to physical and virtual security. Second, we use our findings to critically evaluate the "access, anytime and anywhere" construct shaping the design of future technologies. We present an alternative vision called deliberate interactions--a planned and purposeful interaction style that involves offline preparation and discuss ways ICT can support this online usage behavior. JA - SIGCHI '10 T3 - CHI '10 PB - ACM SN - 978-1-60558-929-9 UR - http://doi.acm.org/10.1145/1753326.1753719 ER - TY - RPRT T1 - Don't Configure the Network, Program It! Domain-Specific Programming Languages for Network Systems Y1 - 2010 A1 - Feamster, Nick A1 - Voellmy,A. A1 - Agarwal,A. A1 - Hudak,P. A1 - Burnett,S. A1 - Launchbury,J. AB - Network operators must configure networks to accomplish critical, complex, and often conflicting requirements: they must ensure good performance while maintaining security, and satisfy contractual obligations while ensuring profitable use of interdomain connections. Unfortunately, today they have no choice but to implement these high-level goals by configuring hundreds of individual network devices. These interact in complex and unexpected ways, often resulting in misconfigurations or downtime. We propose a new approach: rather than configure individual network devices, operators should program the network holistically, according to high-level policies. Towards this goal, we present Nettle, a system for clearly and concisely expressing network requirements together with mechanisms to control the network accordingly. At the lowest level, we rely on OpenFlow switches for programmable network hardware. On top of this layer, we build an extensible family of embedded domain-specific languages (EDSLs), each aimed at different operational concerns and provide convenient ways to sensibly combine expressions in these languages. We present a case study demonstrating a DSL for networks that provides fine-grained, dynamic access control policies. PB - Yale University VL - YALEU/DCS/RR-1432 ER - TY - CONF T1 - Dynamically checking ownership policies in concurrent c/c++ programs T2 - Proceedings of the 37th annual ACM SIGPLAN-SIGACT symposium on Principles of programming languages Y1 - 2010 A1 - Martin,Jean-Phillipe A1 - Hicks, Michael W. A1 - Costa,Manuel A1 - Akritidis,Periklis A1 - Castro,Miguel KW - concurrency KW - Debugging KW - Dynamic analysis KW - Security KW - Testing KW - tools AB - Concurrent programming errors arise when threads share data incorrectly. Programmers often avoid these errors by using synchronization to enforce a simple ownership policy: data is either owned exclusively by a thread that can read or write the data, or it is read owned by a set of threads that can read but not write the data. Unfortunately, incorrect synchronization often fails to enforce these policies and memory errors in languages like C and C++ can violate these policies even when synchronization is correct. In this paper, we present a dynamic analysis for checking ownership policies in concurrent C and C++ programs despite memory errors. The analysis can be used to find errors in commodity multi-threaded programs and to prevent attacks that exploit these errors. We require programmers to write ownership assertions that describe the sharing policies used by different parts of the program. These policies may change over time, as may the policies' means of enforcement, whether it be locks, barriers, thread joins, etc. Our compiler inserts checks in the program that signal an error if these policies are violated at runtime. We evaluated our tool on several benchmark programs. The run-time overhead was reasonable: between 0 and 49% with an average of 26%. We also found the tool easy to use: the total number of ownership assertions is small, and the asserted specification and implementation can be debugged together by running the instrumented program and addressing the errors that arise. Our approach enjoys a pleasing modular soundness property: if a thread executes a sequence of statements on variables it owns, the statements are serializable within a valid execution, and thus their effects can be reasoned about in isolation from other threads in the program. JA - Proceedings of the 37th annual ACM SIGPLAN-SIGACT symposium on Principles of programming languages T3 - POPL '10 PB - ACM CY - New York, NY, USA SN - 978-1-60558-479-9 UR - http://doi.acm.org/10.1145/1706299.1706351 M3 - 10.1145/1706299.1706351 ER - TY - JOUR T1 - An Efficient and Robust Algorithm for Shape Indexing and Retrieval JF - Multimedia, IEEE Transactions on Y1 - 2010 A1 - Biswas,S. A1 - Aggarwal,G. A1 - Chellapa, Rama KW - activity KW - algorithm;shape KW - classification;human KW - databases;robust KW - estimation;large KW - indexing;shape KW - MATCHING KW - matching;image KW - methods;shape KW - pose KW - recognition; KW - retrieval;image KW - retrieval;indexing;shape AB - Many shape matching methods are either fast but too simplistic to give the desired performance or promising as far as performance is concerned but computationally demanding. In this paper, we present a very simple and efficient approach that not only performs almost as good as many state-of-the-art techniques but also scales up to large databases. In the proposed approach, each shape is indexed based on a variety of simple and easily computable features which are invariant to articulations, rigid transformations, etc. The features characterize pairwise geometric relationships between interest points on the shape. The fact that each shape is represented using a number of distributed features instead of a single global feature that captures the shape in its entirety provides robustness to the approach. Shapes in the database are ordered according to their similarity with the query shape and similar shapes are retrieved using an efficient scheme which does not involve costly operations like shape-wise alignment or establishing correspondences. Depending on the application, the approach can be used directly for matching or as a first step for obtaining a short list of candidate shapes for more rigorous matching. We show that the features proposed to perform shape indexing can be used to perform the rigorous matching as well, to further improve the retrieval performance. VL - 12 SN - 1520-9210 CP - 5 M3 - 10.1109/TMM.2010.2050735 ER - TY - JOUR T1 - Evaluation of the Interaction of Cyclin-Dependent Kinase 5 with Activator p25 and with p25-Derived Inhibitor CIP JF - Journal of Computational Biology Y1 - 2010 A1 - Cardone, Antonio A1 - Albers,R.W. A1 - Sriram,R.D. A1 - Pant,H.C. VL - 17 CP - 5 ER - TY - CHAP T1 - An Experimental Study of Color-Based Segmentation Algorithms Based on the Mean-Shift Concept T2 - Computer Vision – ECCV 2010Computer Vision – ECCV 2010 Y1 - 2010 A1 - Bitsakos,K. A1 - Fermüller, Cornelia A1 - Aloimonos, J. ED - Daniilidis,Kostas ED - Maragos,Petros ED - Paragios,Nikos AB - We point out a difference between the original mean-shift formulation of Fukunaga and Hostetler and the common variant in the computer vision community, namely whether the pairwise comparison is performed with the original or with the filtered image of the previous iteration. This leads to a new hybrid algorithm, called Color Mean Shift, that roughly speaking, treats color as Fukunaga’s algorithm and spatial coordinates as Comaniciu’s algorithm. We perform experiments to evaluate how different kernel functions and color spaces affect the final filtering and segmentation results, and the computational speed, using the Berkeley and Weizmann segmentation databases. We conclude that the new method gives better results than existing mean shift ones on four standard comparison measures ( improvement on RAND and BDE measures respectively for color images), with slightly higher running times ( ). Overall, the new method produces segmentations comparable in quality to the ones obtained with current state of the art segmentation algorithms. JA - Computer Vision – ECCV 2010Computer Vision – ECCV 2010 T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 6312 SN - 978-3-642-15551-2 UR - http://dx.doi.org/10.1007/978-3-642-15552-9_37 ER - TY - CONF T1 - Handwritten Arabic text line segmentation using affinity propagation T2 - Proceedings of the 9th IAPR International Workshop on Document Analysis Systems Y1 - 2010 A1 - Kumar,Jayant A1 - Abd-Almageed, Wael A1 - Kang,Le A1 - David Doermann KW - affinity propagation KW - arabic KW - arabic documents KW - breadth-first search KW - clustering KW - dijkstra's shortest path algorithm KW - handwritten documents KW - line detection KW - text line segmentation AB - In this paper, we present a novel graph-based method for extracting handwritten text lines in monochromatic Arabic document images. Our approach consists of two steps - Coarse text line estimation using primary components which define the line and assignment of diacritic components which are more difficult to associate with a given line. We first estimate local orientation at each primary component to build a sparse similarity graph. We then, use a shortest path algorithm to compute similarities between non-neighboring components. From this graph, we obtain coarse text lines using two estimates obtained from Affinity propagation and Breadth-first search. In the second step, we assign secondary components to each text line. The proposed method is very fast and robust to non-uniform skew and character size variations, normally present in handwritten text lines. We evaluate our method using a pixel-matching criteria, and report 96% accuracy on a dataset of 125 Arabic document images. We also present a proximity analysis on datasets generated by artificially decreasing the spacings between text lines to demonstrate the robustness of our approach. JA - Proceedings of the 9th IAPR International Workshop on Document Analysis Systems T3 - DAS '10 PB - ACM CY - New York, NY, USA SN - 978-1-60558-773-8 UR - http://doi.acm.org/10.1145/1815330.1815348 M3 - 10.1145/1815330.1815348 ER - TY - JOUR T1 - On the importance of sharing negative results JF - SIGKDD explorations Y1 - 2010 A1 - Giraud-Carrier,C. A1 - Dunham,M.H. A1 - Atreya,A. A1 - Elkan,C. A1 - Perlich,C. A1 - Swirszcz,G. A1 - Shi,X. A1 - Philip,S.Y. A1 - Fürnkranz,J. A1 - Sima,J.F. VL - 12 CP - 2 ER - TY - JOUR T1 - Insights into head-related transfer function: Spatial dimensionality and continuous representation JF - The Journal of the Acoustical Society of America Y1 - 2010 A1 - Zhang,Wen A1 - Abhayapala,Thushara D. A1 - Kennedy,Rodney A. A1 - Duraiswami, Ramani KW - acoustic signal processing KW - Bessel functions KW - Fourier series KW - hearing KW - Transfer functions AB - This paper studies head-related transfer function (HRTF) sampling and synthesis in a three-dimensional auditory scene based on a general modal decomposition of the HRTF in all frequency-range-angle domains. The main finding is that the HRTF decomposition with the derived spatial basis function modes can be well approximated by a finite number, which is defined as the spatial dimensionality of the HRTF. The dimensionality determines the minimum number of parameters to represent the HRTF corresponding to all directions and also the required spatial resolution in HRTF measurement. The general model is further developed to a continuous HRTF representation, in which the normalized spatial modes can achieve HRTF near-field and far-field representations in one formulation. The remaining HRTF spectral components are compactly represented using a Fourier spherical Bessel series, where the aim is to generate the HRTF with much higher spectral resolution in fewer parameters from typical measurements, which usually have limited spectral resolution constrained by sampling conditions. A low-computation algorithm is developed to obtain the model coefficients from the existing measurements. The HRTF synthesis using the proposed model is validated by three sets of data: (i) synthetic HRTFs from the spherical head model, (ii) the MIT KEMAR (Knowles Electronics Mannequin for Acoustics Research) data, and (iii) 45-subject CIPIC HRTF measurements. VL - 127 UR - http://link.aip.org/link/?JAS/127/2347/1 CP - 4 M3 - 10.1121/1.3336399 ER - TY - RPRT T1 - Interactive information visualization for exploring and querying electronic health records: A systematic review Y1 - 2010 A1 - Rind,A. A1 - Wang,T. D A1 - Aigner,W. A1 - Miksh,S. A1 - Wongsuphasawat,K. A1 - Plaisant, Catherine A1 - Shneiderman, Ben AB - To overcome the complexity and scale of making medical decisions based on electronic health records (EHRs) a variety of visual methods have been proposed. This paper surveys twelve state-of-the-art information visualization systems described in the scientific literature and compares them based on a set of carefully selected criteria. It aims to systematically examine the systems’ strengths and weaknesses to inform future information visualization designs.We select twelve state-of-the-art information visualization systems from information visualization, medical information systems and human-computer interaction conferences and journals. We compare the systems using the following criteria: (1) data types covered, (2) multivariate analysis support, (3) number of patients records used (one or many), and (4) user intents addressed. The review describes the twelve systems in detail and evaluates the systems using the aforementioned criteria. We discuss how the systems differ in their features and highlight how these differences are related to their design and affect the user intent model. Examples of findings include: (1) most systems handle numerical or categorical data but not both, (2) most systems are specifically designed for looking at a single patient or multiple patients but not both, (3) most systems utilize horizontal time lines to represent time, (4) only systems that handle multiple patient records have good support for Filter, and (5) some specific user intents (e.g. the Encode and Connect intents) are rarely addressed. Based on our review results, we believe that effective information visualization can facilitate analysis of patient records, and we encourage the information visualization community to study the application of their systems and conduct more in depth evaluations. We identify potential future research topics in interactive support for data abstraction and medical tasks that involve looking at a single or multiple records. Finally, we propose to create a repository for data and tasks so benchmarks can be established for both academic and commercial patient record visualization systems. PB - Human-Computer Interaction Lab, University of Maryland ER - TY - CONF T1 - Learning shift-invariant sparse representation of actions T2 - 2010 IEEE Conference on Computer Vision and Pattern Recognition (CVPR) Y1 - 2010 A1 - Li,Yi A1 - Fermüller, Cornelia A1 - Aloimonos, J. A1 - Hui Ji KW - action characterization KW - Action recognition KW - action retrieval KW - action synthesis KW - Character recognition KW - data compression KW - human motion capture KW - HUMANS KW - Image matching KW - Image motion analysis KW - image representation KW - Image sequences KW - Information retrieval KW - joint movements KW - large convex minimizations KW - learning (artificial intelligence) KW - learning shift-invariant sparse representation KW - Matching pursuit algorithms KW - minimisation KW - Minimization methods KW - MoCap data compression KW - Motion analysis KW - motion capture analysis KW - motion disorder disease KW - motion sequences KW - orthogonal matching pursuit KW - Parkinson diagnosis KW - Parkinson's disease KW - Pursuit algorithms KW - shift-invariant basis functions KW - short basis functions KW - snippets KW - sparse linear combination KW - split Bregman algorithm KW - time series KW - time series data KW - Unsupervised learning KW - unsupervised learning algorithm AB - A central problem in the analysis of motion capture (MoCap) data is how to decompose motion sequences into primitives. Ideally, a description in terms of primitives should facilitate the recognition, synthesis, and characterization of actions. We propose an unsupervised learning algorithm for automatically decomposing joint movements in human motion capture (MoCap) sequences into shift-invariant basis functions. Our formulation models the time series data of joint movements in actions as a sparse linear combination of short basis functions (snippets), which are executed (or “activated”) at different positions in time. Given a set of MoCap sequences of different actions, our algorithm finds the decomposition of MoCap sequences in terms of basis functions and their activations in time. Using the tools of L1 minimization, the procedure alternately solves two large convex minimizations: Given the basis functions, a variant of Orthogonal Matching Pursuit solves for the activations, and given the activations, the Split Bregman Algorithm solves for the basis functions. Experiments demonstrate the power of the decomposition in a number of applications, including action recognition, retrieval, MoCap data compression, and as a tool for classification in the diagnosis of Parkinson (a motion disorder disease). JA - 2010 IEEE Conference on Computer Vision and Pattern Recognition (CVPR) PB - IEEE SN - 978-1-4244-6984-0 M3 - 10.1109/CVPR.2010.5539977 ER - TY - CONF T1 - The Metacognitive Loop: An Architecture for Building Robust Intelligent Systems T2 - 2010 AAAI Fall Symposium Series Y1 - 2010 A1 - Shahri,Hamid Haidarian A1 - Dinalankara,Wikum A1 - Fults,Scott A1 - Wilson,Shomir A1 - Perlis, Don A1 - Schmill,Matt A1 - Oates,Tim A1 - Josyula,Darsana A1 - Anderson,Michael KW - commonsense KW - ontologies KW - robust intelligent systems AB - The Metacognitive Loop: An Architecture for Building Robust Intelligent Systems JA - 2010 AAAI Fall Symposium Series UR - http://www.aaai.org/ocs/index.php/FSS/FSS10/paper/view/2161 ER - TY - CHAP T1 - Multidimensional data structures for spatial applications T2 - Algorithms and theory of computation handbookAlgorithms and theory of computation handbook Y1 - 2010 A1 - Samet, Hanan ED - Atallah,Mikhail J. ED - Blanton,Marina AB - An overview is presented of a number of representations of multidimensional data that arise in spatial applications. Multidimensional spatial data consists of points as well as objects that have extent such as line segments, rectangles, regions, and volumes. The points may have locational as well as nonlocational attributes. The focus is on spatial data which is a subset of multidimensional data consisting of points with locational attributes and objects with extent. The emphasis is on hierarchical representations based on the "divide-and-conquer" problem-solving paradigm. They are of interest because they enable focusing computational resources on the interesting subsets of data. Thus, there is no need to expend work where the payoff is small. These representations are of use in operations such as range searching and finding nearest neighbors. JA - Algorithms and theory of computation handbookAlgorithms and theory of computation handbook PB - Chapman & Hall/CRC SN - 978-1-58488-822-2 UR - http://dl.acm.org/citation.cfm?id=1882757.1882763 ER - TY - CONF T1 - Network I/O fairness in virtual machines T2 - Proceedings of the second ACM SIGCOMM workshop on Virtualized infrastructure systems and architectures Y1 - 2010 A1 - Anwer,Muhammad Bilal A1 - Nayak,Ankur A1 - Feamster, Nick A1 - Liu,Ling KW - netfpga KW - network virtualization KW - xen AB - We present a mechanism for achieving network I/O fairness in virtual machines, by applying flexible rate limiting mechanisms directly to virtual network interfaces. Conventional approaches achieve this fairness by implementing rate limiting either in the virtual machine monitor or hypervisor, which generates considerable CPU interrupt and instruction overhead for forwarding packets. In contrast, our design pushes per-VM rate limiting as close as possible to the physical hardware themselves, effectively implementing per-virtual interface rate limiting in hardware. We show that this design reduces CPU overhead (both interrupts and instructions) by an order of magnitude. Our design can be applied either to virtual servers for cloud-based services, or to virtual routers JA - Proceedings of the second ACM SIGCOMM workshop on Virtualized infrastructure systems and architectures T3 - VISA '10 PB - ACM CY - New York, NY, USA SN - 978-1-4503-0199-2 UR - http://doi.acm.org/10.1145/1851399.1851412 M3 - 10.1145/1851399.1851412 ER - TY - PAT T1 - Object Classification Using Taxonomies Y1 - 2010 A1 - Tsaparas,Panayiotis A1 - Papadimitriou,Panagiotis A1 - Fuxman,Ariel D. A1 - Getoor, Lise A1 - Agrawal,Rakesh ED - Microsoft Corporation AB - As provided herein objects from a source catalog, such as a provider's catalog, can be added to a target catalog, such as an enterprise master catalog, in a scalable manner utilizing catalog taxonomies. A baseline classifier determines probabilities for source objects to target catalog classes. Source objects can be assigned to those classes with probabilities that meet a desired threshold and meet a desired rate. A classification cost for target classes can be determined for respective unassigned source objects, which can comprise determining an assignment cost and separation cost for the source objects for respective desired target classes. The separation and assignment costs can be combined to determine the classification cost, and the unassigned source objects can be assigned to those classes having a desired classification cost. VL - 12/414,065 UR - http://www.google.com/patents?id=oXDSAAAAEBAJ ER - TY - CONF T1 - Ontuition: intuitive data exploration via ontology navigation T2 - Proceedings of the 18th SIGSPATIAL International Conference on Advances in Geographic Information Systems Y1 - 2010 A1 - Adelfio,Marco D. A1 - Lieberman,Michael D. A1 - Samet, Hanan A1 - Firozvi,Kashif A. KW - MAPPING KW - ontology KW - ontuition KW - spatio-textual AB - Ontuition, a system for mapping ontologies, is presented. Transforming data to a usable format for Ontuition involves recognizing and resolving data values corresponding to concepts in multiple ontological domains. In particular, for datasets with a geographic component an attempt is made to identify and extract enough spatio-textual data that specific lat/long values to dataset entries can be assigned. Next, a gazetteer is used to transform the textually-specified locations into lat/long values that can be displayed on a map. Non-spatial ontological concepts are also discovered. This methodology is applied to the National Library of Medicine's very popular clinical trials website (http://clinicaltrials.gov/) whose users are generally interested in locating trials near where they live. The trials are specified using XML files. The location data is extracted and coupled with a disease ontology to enable general queries on the data with the result being of use to a very large group of people. The goal is to do this automatically for such ontology datasets with a locational component. JA - Proceedings of the 18th SIGSPATIAL International Conference on Advances in Geographic Information Systems T3 - GIS '10 PB - ACM CY - New York, NY, USA SN - 978-1-4503-0428-3 UR - http://doi.acm.org/10.1145/1869790.1869887 M3 - 10.1145/1869790.1869887 ER - TY - JOUR T1 - Overlap-based cell tracker JF - The Journal of Research of the National Institute of Standards and Technology Y1 - 2010 A1 - Chalfoun, J A1 - Cardone, Antonio A1 - Dima, A.A. A1 - Allen, D.P. A1 - Halter, M.W. AB - order to facilitate the extraction of quantitative data from live cell image sets, automated image analysis methods are needed. This paper presents an introduction to the general principle of an overlap cell tracking software developed by the National Institute of Standards and Technology (NIST). This cell tracker has the ability to track cells across a set of time lapse images acquired at high rates based on the amount of overlap between cellular regions in consecutive frames. It is designed to be highly flexible, requires little user parameterization, and has a fast execution time. VL - 115 CP - 6 ER - TY - JOUR T1 - PADS: A Probabilistic Activity Detection Framework for Video Data JF - Pattern Analysis and Machine Intelligence, IEEE Transactions on Y1 - 2010 A1 - Albanese, M. A1 - Chellapa, Rama A1 - Cuntoor, N. A1 - Moscato, V. A1 - Picariello, A. A1 - V.S. Subrahmanian A1 - Udrea,O. KW - Automated;Programming Languages;Video Recording; KW - Computer-Assisted;Models KW - PADL;PADS;image processing algorithms;offPad algorithm;onPad algorithm;probabilistic activity description language;probabilistic activity detection framework;video data;video sequence;image sequences;object detection;probability;video surveillance;Algorit KW - Statistical;Movement;Pattern Recognition AB - There is now a growing need to identify various kinds of activities that occur in videos. In this paper, we first present a logical language called Probabilistic Activity Description Language (PADL) in which users can specify activities of interest. We then develop a probabilistic framework which assigns to any subvideo of a given video sequence a probability that the subvideo contains the given activity, and we finally develop two fast algorithms to detect activities within this framework. OffPad finds all minimal segments of a video that contain a given activity with a probability exceeding a given threshold. In contrast, the OnPad algorithm examines a video during playout (rather than afterwards as OffPad does) and computes the probability that a given activity is occurring (even if the activity is only partially complete). Our prototype Probabilistic Activity Detection System (PADS) implements the framework and the two algorithms, building on top of existing image processing algorithms. We have conducted detailed experiments and compared our approach to four different approaches presented in the literature. We show that-for complex activity definitions-our approach outperforms all the other approaches. VL - 32 SN - 0162-8828 CP - 12 M3 - 10.1109/TPAMI.2010.33 ER - TY - CONF T1 - Performance Evaluation Tools for Zone Segmentation and Classification (PETS) T2 - International Conference on Pattern Recognition Y1 - 2010 A1 - Seo,W. A1 - Agrawal,Mudit A1 - David Doermann AB - This paper overviews a set of Performance Evaluation ToolS (PETS) for zone segmentation and classification. The tools allow researchers and developers to evaluate, optimize and compare their algorithms by providing a variety of quantitative performance metrics. The evaluation of segmentation quality is based on the pixel-based overlaps between two sets of regions proposed by Randriamasy and Vincent. PETS extends the approach by providing a set of metrics for overlap analysis, RLE and polygonal representation of regions and introduces type-matching to evaluate zone classification. The software is available for research use. JA - International Conference on Pattern Recognition ER - TY - JOUR T1 - Perturbing the Ubiquitin Pathway Reveals How Mitosis Is Hijacked to Denucleate and Regulate Cell Proliferation and Differentiation In Vivo JF - PLoS ONEPLoS ONE Y1 - 2010 A1 - Caceres,Andrea A1 - Shang,Fu A1 - Wawrousek,Eric A1 - Liu,Qing A1 - Avidan,Orna A1 - Cvekl,Ales A1 - Yang,Ying A1 - Haririnia,Aydin A1 - Storaska,Andrew A1 - Fushman, David A1 - Kuszak,Jer A1 - Dudek,Edward A1 - Smith,Donald A1 - Taylor,Allen AB - BackgroundThe eye lens presents a unique opportunity to explore roles for specific molecules in cell proliferation, differentiation and development because cells remain in place throughout life and, like red blood cells and keratinocytes, they go through the most extreme differentiation, including removal of nuclei and cessation of protein synthesis. Ubiquitination controls many critical cellular processes, most of which require specific lysines on ubiquitin (Ub). Of the 7 lysines (K) least is known about effects of modification of K6. Methodology and Principal Findings We replaced K6 with tryptophan (W) because K6 is the most readily modified K and W is the most structurally similar residue to biotin. The backbone of K6W-Ub is indistinguishable from that of Wt-Ub. K6W-Ub is effectively conjugated and deconjugated but the conjugates are not degraded via the ubiquitin proteasome pathways (UPP). Expression of K6W-ubiquitin in the lens and lens cells results in accumulation of intracellular aggregates and also slows cell proliferation and the differentiation program, including expression of lens specific proteins, differentiation of epithelial cells into fibers, achieving proper fiber cell morphology, and removal of nuclei. The latter is critical for transparency, but the mechanism by which cell nuclei are removed has remained an age old enigma. This was also solved by expressing K6W-Ub. p27kip, a UPP substrate accumulates in lenses which express K6W-Ub. This precludes phosphorylation of nuclear lamin by the mitotic kinase, a prerequisite for disassembly of the nuclear membrane. Thus the nucleus remains intact and DNAseIIβ neither gains entry to the nucleus nor degrades the DNA. These results could not be obtained using chemical proteasome inhibitors that cannot be directed to specific tissues. Conclusions and Significance K6W-Ub provides a novel, genetic means to study functions of the UPP because it can be targeted to specific cells and tissues. A fully functional UPP is required to execute most stages of lens differentiation, specifically removal of cell nuclei. In the absence of a functional UPP, small aggregate prone, cataractous lenses are formed. VL - 5 UR - http://dx.doi.org/10.1371/journal.pone.0013331 CP - 10 M3 - 10.1371/journal.pone.0013331 ER - TY - CONF T1 - Pose estimation in heavy clutter using a multi-flash camera T2 - Robotics and Automation (ICRA), 2010 IEEE International Conference on Y1 - 2010 A1 - Ming-Yu Liu A1 - Tuzel, O. A1 - Veeraraghavan,A. A1 - Chellapa, Rama A1 - Agrawal,A. A1 - Okuda, H. KW - 3D KW - algorithm;object KW - based KW - camera;multiview KW - depth KW - detection;object KW - detection;pose KW - distance KW - edge KW - edges;cameras;image KW - edges;integral KW - estimation;binary KW - estimation;multiflash KW - estimation;robot KW - function;depth KW - images;location KW - localization;pose KW - maps KW - matching;cost KW - matching;image KW - pose-refinement KW - texture;object KW - transforms;angular KW - vision;texture KW - vision;transforms; AB - We propose a novel solution to object detection, localization and pose estimation with applications in robot vision. The proposed method is especially applicable when the objects of interest may not be richly textured and are immersed in heavy clutter. We show that a multi-flash camera (MFC) provides accurate separation of depth edges and texture edges in such scenes. Then, we reformulate the problem, as one of finding matches between the depth edges obtained in one or more MFC images to the rendered depth edges that are computed offline using 3D CAD model of the objects. In order to facilitate accurate matching of these binary depth edge maps, we introduce a novel cost function that respects both the position and the local orientation of each edge pixel. This cost function is significantly superior to traditional Chamfer cost and leads to accurate matching even in heavily cluttered scenes where traditional methods are unreliable. We present a sub-linear time algorithm to compute the cost function using techniques from 3D distance transforms and integral images. Finally, we also propose a multi-view based pose-refinement algorithm to improve the estimated pose. We implemented the algorithm on an industrial robot arm and obtained location and angular estimation accuracy of the order of 1 mm and 2 #x00B0; respectively for a variety of parts with minimal texture. JA - Robotics and Automation (ICRA), 2010 IEEE International Conference on M3 - 10.1109/ROBOT.2010.5509897 ER - TY - JOUR T1 - Reversible Post-Translational Carboxylation Modulates the Enzymatic Activity of N-Acetyl-l-ornithine Transcarbamylase JF - Biochemistry Y1 - 2010 A1 - Li,Yongdong A1 - Yu,Xiaolin A1 - Ho,Jeremy A1 - Fushman, David A1 - Allewell,Norma M. A1 - Tuchman,Mendel A1 - Shi,Dashuang AB - N-Acetyl-l-ornithine transcarbamylase (AOTCase), rather than ornithine transcarbamylase (OTCase), is the essential carbamylase enzyme in the arginine biosynthesis of several plant and human pathogens. The specificity of this unique enzyme provides a potential target for controlling the spread of these pathogens. Recently, several crystal structures of AOTCase from Xanthomonas campestris (xc) have been determined. In these structures, an unexplained electron density at the tip of the Lys302 side chain was observed. Using 13C NMR spectroscopy, we show herein that Lys302 is post-translationally carboxylated. The structure of wild-type AOTCase in a complex with the bisubstrate analogue Nδ-(phosphonoacetyl)-Nα-acetyl-l-ornithine (PALAO) indicates that the carboxyl group on Lys302 forms a strong hydrogen bonding network with surrounding active site residues, Lys252, Ser253, His293, and Glu92 from the adjacent subunit either directly or via a water molecule. Furthermore, the carboxyl group is involved in binding N-acetyl-l-ornithine via a water molecule. Activity assays with the wild-type enzyme and several mutants demonstrate that the post-translational modification of lysine 302 has an important role in catalysis.N-Acetyl-l-ornithine transcarbamylase (AOTCase), rather than ornithine transcarbamylase (OTCase), is the essential carbamylase enzyme in the arginine biosynthesis of several plant and human pathogens. The specificity of this unique enzyme provides a potential target for controlling the spread of these pathogens. Recently, several crystal structures of AOTCase from Xanthomonas campestris (xc) have been determined. In these structures, an unexplained electron density at the tip of the Lys302 side chain was observed. Using 13C NMR spectroscopy, we show herein that Lys302 is post-translationally carboxylated. The structure of wild-type AOTCase in a complex with the bisubstrate analogue Nδ-(phosphonoacetyl)-Nα-acetyl-l-ornithine (PALAO) indicates that the carboxyl group on Lys302 forms a strong hydrogen bonding network with surrounding active site residues, Lys252, Ser253, His293, and Glu92 from the adjacent subunit either directly or via a water molecule. Furthermore, the carboxyl group is involved in binding N-acetyl-l-ornithine via a water molecule. Activity assays with the wild-type enzyme and several mutants demonstrate that the post-translational modification of lysine 302 has an important role in catalysis. VL - 49 SN - 0006-2960 UR - http://dx.doi.org/10.1021/bi1007386 CP - 32 M3 - 10.1021/bi1007386 ER - TY - CHAP T1 - Semantic Video Content Analysis T2 - Video Search and MiningVideo Search and Mining Y1 - 2010 A1 - Albanese,Massimiliano A1 - Turaga,Pavan A1 - Chellapa, Rama A1 - Pugliese,Andrea A1 - Subrahmanian,V. ED - Schonfeld,Dan ED - Shan,Caifeng ED - Tao,Dacheng ED - Wang,Liang AB - In recent years, there has been significant interest in the area of automatically recognizing activities occurring in a camera’s field of view and detecting abnormalities. The practical applications of such a system could include airport tarmac monitoring, or monitoring of activities in secure installations, to name a few. The difficulty of the problem is compounded by several factors: detection of primitive actions in spite of changes in illumination, occlusions and noise; complexmultiagent interaction;mapping of higher-level activities to lower-level primitive actions; variations in which the same semantic activity can be performed. In this chapter, we develop a theory of semantic activity analysis that addresses each of these issues in an integrated manner. Specifically, we discuss ontological representations of knowledge of a domain, integration of domain knowledge and statistical models for achieving semantic mappings, definition of logical languages to describe activities, and design of frameworks which integrate all the above aspects in a coherent way, thus laying the foundations of effective Semantic Video Content Analysis systems. JA - Video Search and MiningVideo Search and Mining T3 - Studies in Computational Intelligence PB - Springer Berlin / Heidelberg VL - 287 SN - 978-3-642-12899-8 UR - http://dx.doi.org/10.1007/978-3-642-12900-1_6 ER - TY - JOUR T1 - THE SHAKY LADDER HYPERPLANE-DEFINED FUNCTIONS AND CLASSIC DYNAMIC PROBLEMS JF - International Journal of Computational Intelligence and Applications Y1 - 2010 A1 - Alharbi,Abir A1 - Rand, William AB - To improve the understanding of the GA in dynamic environments we explore a set of test problems, the shaky ladder hyper-defined functions (sl-hdf), and extend these functions to create versions that are equivalent to many classical dynamic problems. We do this by constraining the space of all sl-hdfs to create representations of these classical functions. We have examined three classical problems, and compared sl-hdf versions of these problems with their standard representations. These results show that the sl-hdfs are representative of a larger class of problems, and can represent a larger class of test suite. Previous results on sl-hdf showed that GA performance is best in the Defined Cliffs variant of the sl-hdf. We build upon these results to improve GA performance in several classes of real world dynamic problems by modifying the problem representation. These results lend insight into dynamic problems where the GA will perform well. VL - 09 SN - 1469-0268 UR - http://www.worldscinet.com/ijcia/09/0901/S1469026810002756.html CP - 01 M3 - 10.1142/S1469026810002756 ER - TY - JOUR T1 - Structural and dynamic determinants of ligand binding and regulation of cyclin-dependent kinase 5 by pathological activator p25 and inhibitory peptide CIP. JF - Journal of molecular biology Y1 - 2010 A1 - Cardone, Antonio A1 - Hassan, S A A1 - Albers,R.W. A1 - Sriram,R.D. A1 - Pant,H.C. KW - Crystallography, X-Ray KW - Cyclin-Dependent Kinase 5 KW - Cyclin-Dependent Kinase Inhibitor Proteins KW - HUMANS KW - Ligands KW - molecular dynamics simulation KW - Nerve Tissue Proteins KW - Principal component analysis KW - Protein Binding KW - Protein Conformation AB - The crystal structure of the cdk5/p25 complex has provided information on possible molecular mechanisms of the ligand binding, specificity, and regulation of the kinase. Comparative molecular dynamics simulations are reported here for physiological conditions. This study provides new insight on the mechanisms that modulate such processes, which may be exploited to control pathological activation by p25. The structural changes observed in the kinase are stabilized by a network of interactions involving highly conserved residues within the cyclin-dependent kinase (cdk) family. Collective motions of the proteins (cdk5, p25, and CIP) and their complexes are identified by principal component analysis, revealing two conformational states of the activation loop upon p25 complexation, which are absent in the uncomplexed kinase and not apparent from the crystal. Simulations of the uncomplexed inhibitor CIP show structural rearrangements and increased flexibility of the interfacial loop containing the critical residue E240, which becomes fully hydrated and available for interactions with one of several positively charged residues in the kinase. These changes provide a rationale for the observed high affinity and enhanced inhibitory action of CIP when compared to either p25 or the physiological activators of cdk5. VL - 401 CP - 3 U1 - http://www.ncbi.nlm.nih.gov/pubmed/20599546?dopt=Abstract M3 - 10.1016/j.jmb.2010.06.040 ER - TY - JOUR T1 - SwitchBlade: a platform for rapid deployment of network protocols on programmable hardware JF - SIGCOMM Comput. Commun. Rev. Y1 - 2010 A1 - Anwer,Muhammad Bilal A1 - Motiwala,Murtaza A1 - Bin Tariq,Mukarram A1 - Feamster, Nick KW - netfpga KW - network virtualization AB - We present SwitchBlade, a platform for rapidly deploying custom protocols on programmable hardware. SwitchBlade uses a pipeline-based design that allows individual hardware modules to be enabled or disabled on the fly, integrates software exception handling, and provides support for forwarding based on custom header fields. SwitchBlade's ease of programmability and wire-speed performance enables rapid prototyping of custom data-plane functions that can be directly deployed in a production network. SwitchBlade integrates common packet-processing functions as hardware modules, enabling different protocols to use these functions without having to resynthesize hardware. SwitchBlade's customizable forwarding engine supports both longest-prefix matching in the packet header and exact matching on a hash value. SwitchBlade's software exceptions can be invoked based on either packet or flow-based rules and updated quickly at runtime, thus making it easy to integrate more flexible forwarding function into the pipeline. SwitchBlade also allows multiple custom data planes to operate in parallel on the same physical hardware, while providing complete isolation for protocols running in parallel. We implemented SwitchBlade using NetFPGA board, but SwitchBlade can be implemented with any FPGA. To demonstrate SwitchBlade's flexibility, we use SwitchBlade to implement and evaluate a variety of custom network protocols: we present instances of IPv4, IPv6, Path Splicing, and an OpenFlow switch, all running in parallel while forwarding packets at line rate. VL - 40 SN - 0146-4833 UR - http://doi.acm.org/10.1145/1851275.1851206 CP - 4 M3 - 10.1145/1851275.1851206 ER - TY - CONF T1 - A Systematic Methodology for Accurate Design-Stage Estimation of Energy Consumption for Injection Molded Parts Y1 - 2010 A1 - Weissman,A. A1 - Ananthanarayanan,A. A1 - Gupta,S.K. A1 - Sriram,R.D. AB - Today's ubiquitous use of plastics in product designand manufacturing presents significant environmental and human health challenges. Injection molding, one of the most commonly used processes for making plastic products, consumes a significant amount of energy. A methodology for accurately estimating the energy consumed to injection-mold a part would enable environmentally conscious decision making during the product design. Unfortunately, only limited information is available at the design stage. Therefore, accurately estimating energy consumption before the part has gone into production can be challenging. In this paper, we describe a methodology for energy estimation that works with the limited amount of data available during the design stage, namely the CAD model of the part, the material name, and the production requirements. This methodology uses this data to estimate the parameters of the runner system and an appropriately sized molding machine. It then uses these estimates to compute the machine setup time and the cycle time required for the injection molding operation. This is done by appropriately abstracting information available from the mold flow simulation tools and analytical models that are traditionally used during the manufacturing stage. These times are then multiplied by the power consumed by the appropriately sized machine during each stage of the molding cycle to compute the estimated energy consumption per part. UR - http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.165.4139&rep=rep1&type=pdf ER - TY - CHAP T1 - Technology-Mediated Social Participation: Deep Science and Extreme Technology T2 - Active Media TechnologyActive Media Technology Y1 - 2010 A1 - Shneiderman, Ben ED - An,Aijun ED - Lingras,Pawan ED - Petty,Sheila ED - Huang,Runhe AB - The dramatic success of social media such as Facebook, Twitter, YouTube, Flickr, blogs, and traditional discussion groups empowers individuals to become active in local and global communities. With modest redesign, these technologies can be harnessed to support national priorities such as healthcare/wellness, disaster response, community safety, energy sustainability, etc. This talk describes a research agenda for these topics that develops deep science questions and extreme technology challenges. JA - Active Media TechnologyActive Media Technology T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 6335 SN - 978-3-642-15469-0 UR - http://dx.doi.org/10.1007/978-3-642-15470-6_1 ER - TY - CONF T1 - Tight lower bounds for halfspace range searching T2 - Proceedings of the 2010 annual symposium on Computational geometry Y1 - 2010 A1 - Arya,Sunil A1 - Mount, Dave A1 - Xia,Jian KW - Idempotence KW - lower bounds KW - Range searching AB - We establish two new lower bounds for the halfspace range searching problem: Given a set of n points in ℜd, where each point is associated with a weight from a commutative semigroup, compute the semigroup sum of the weights of the points lying within any query halfspace. Letting $m$ denote the space requirements, we prove a lower bound for general semigroups of Ω(n1-1/(d+1)/m1/(d+1)) and for integral semigroups of Ω(n/m1/d). Our lower bounds are proved in the semigroup arithmetic model. Neglecting logarithmic factors, our result for integral semigroups matches the best known upper bound due to Matoušek. Our result for general semigroups improves upon the best known lower bound due to Brönnimann, Chazelle, and Pach. Moreover, Fonseca and Mount have recently shown that, given uniformly distributed points, halfspace range queries over idempotent semigroups can be answered in O(n1-1/(d+1)/m1/(d+1)) time in the semigroup arithmetic model. As our lower bounds are established for uniformly distributed point sets, it follows that they also resolve the computational complexity of halfspace range searching over idempotent semigroups in this important special case. JA - Proceedings of the 2010 annual symposium on Computational geometry T3 - SoCG '10 PB - ACM CY - New York, NY, USA SN - 978-1-4503-0016-2 UR - http://doi.acm.org/10.1145/1810959.1810964 M3 - 10.1145/1810959.1810964 ER - TY - CONF T1 - Toque: designing a cooking-based programming language for and with children T2 - Proceedings of the 28th international conference on Human factors in computing systems Y1 - 2010 A1 - Tarkan,S. A1 - Sazawal,V. A1 - Druin, Allison A1 - Golub,E. A1 - Bonsignore,E. M A1 - Walsh,G. A1 - Atrash,Z. JA - Proceedings of the 28th international conference on Human factors in computing systems ER - TY - JOUR T1 - A unified approach to approximate proximity searching JF - Algorithms–ESA 2010 Y1 - 2010 A1 - Arya,S. A1 - da Fonseca,G. A1 - Mount, Dave ER - TY - CHAP T1 - Visualizing Threaded Conversation Networks: Mining Message Boards and Email Lists for Actionable Insights T2 - Active Media TechnologyActive Media Technology Y1 - 2010 A1 - Hansen,Derek A1 - Shneiderman, Ben A1 - Smith,Marc ED - An,Aijun ED - Lingras,Pawan ED - Petty,Sheila ED - Huang,Runhe AB - Analyzing complex online relationships is a difficult job, but new information visualization tools are enabling a wider range of users to make actionable insights from the growing volume of online data. This paper describes the challenges and methods for conducting analyses of threaded conversations such as found in enterprise message boards, email lists, and forums. After defining threaded conversation, we characterize the types of networks that can be extracted from them. We then provide 3 mini case studies to illustrate how actionable insights for community managers can be gained by applying the network analysis metrics and visualizations available in the free, open source NodeXL tool, which is a powerful, yet easy-to-use tool embedded in Excel 2007/2010. JA - Active Media TechnologyActive Media Technology T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 6335 SN - 978-3-642-15469-0 UR - http://dx.doi.org/10.1007/978-3-642-15470-6_7 ER - TY - CONF T1 - WATTR: a method for self-powered wireless sensing of water activity in the home T2 - Proceedings of the 12th ACM international conference on Ubiquitous computing Y1 - 2010 A1 - Campbell,Tim A1 - Larson,Eric A1 - Cohn,Gabe A1 - Jon Froehlich A1 - Alcaide,Ramses A1 - Patel,Shwetak N. KW - power harvesting KW - sensing KW - water conservation JA - Proceedings of the 12th ACM international conference on Ubiquitous computing T3 - Ubicomp '10 PB - ACM CY - New York, NY, USA SN - 978-1-60558-843-8 UR - http://doi.acm.org/10.1145/1864349.1864378 M3 - 10.1145/1864349.1864378 ER - TY - JOUR T1 - 3D Face Recognition: Technology and Applications JF - Handbook of Remote Biometrics Y1 - 2009 A1 - Tistarelli,M. A1 - Li, S.Z. A1 - Chellapa, Rama A1 - Akarun, L. ER - TY - CONF T1 - Active segmentation for robotics T2 - IEEE/RSJ International Conference on Intelligent Robots and Systems, 2009. IROS 2009 Y1 - 2009 A1 - Mishra,A. A1 - Aloimonos, J. A1 - Fermüller, Cornelia KW - binocular cues KW - image colour analysis KW - Image segmentation KW - Image texture KW - Intelligent robots KW - Layout KW - Machine vision KW - monocular cues KW - Navigation KW - optical flow KW - Orbital robotics KW - Robot sensing systems KW - robot vision KW - Robot vision systems KW - robotics active segmentation KW - Robotics and automation KW - semantic robot KW - Simultaneous localization and mapping KW - stereo disparity KW - stereo image processing AB - The semantic robots of the immediate future are robots that will be able to find and recognize objects in any environment. They need the capability of segmenting objects in their visual field. In this paper, we propose a novel approach to segmentation based on the operation of fixation by an active observer. Our approach is different from current approaches: while existing works attempt to segment the whole scene at once into many areas, we segment only one image region, specifically the one containing the fixation point. Furthermore, our solution integrates monocular cues (color, texture) with binocular cues (stereo disparities and optical flow). Experiments with real imagery collected by our active robot and from the known databases demonstrate the promise of the approach. JA - IEEE/RSJ International Conference on Intelligent Robots and Systems, 2009. IROS 2009 PB - IEEE SN - 978-1-4244-3803-7 M3 - 10.1109/IROS.2009.5354325 ER - TY - CONF T1 - Analyzing the process of installing rogue software Y1 - 2009 A1 - Berthier,R. A1 - Arjona,J. A1 - Michel Cukier KW - Linux KW - Linux target computers KW - malicious actions KW - rogue software installation KW - security of data AB - This practical experience report presents the results of an experiment aimed at understanding the sequence of malicious actions following a remote compromise. The type of rogue software installed during attacks was used to classify and understand sequences of malicious actions. For this experiment, we used four Linux target computers running SSH with simple passwords. During the eight-month data collection period, we recorded a total of 1,171 attack sessions. In these sessions, attackers typed a total of 20,335 commands that we categorized into 24 specific actions. These actions were analyzed based on the type of rogue software installed by attackers. M3 - 10.1109/DSN.2009.5270293 ER - TY - CONF T1 - Approximate kernel matrix computation on GPUs forlarge scale learning applications T2 - Proceedings of the 23rd international conference on Supercomputing Y1 - 2009 A1 - Hussein,Mohamed E A1 - Abd-Almageed, Wael KW - affinity propagation KW - algorithms KW - arrays KW - gpu KW - kernel methods KW - parallel programming KW - performance KW - space filling curves KW - sparse matrices AB - Kernel-based learning methods require quadratic space and time complexities to compute the kernel matrix. These complexities limit the applicability of kernel methods to large scale problems with millions of data points. In this paper, we introduce a novel representation of kernel matrices on Graphics Processing Units (GPU). The novel representation exploits the sparseness of the kernel matrix to address the space complexity problem. It also respects the guidelines for memory access on GPUs, which are critical for good performance, to address the time complexity problem. Our representation utilizes the locality preserving properties of space filling curves to obtain a band approximation of the kernel matrix. To prove the validity of the representation, we use Affinity Propagation, an unsupervised clustering algorithm, as an example of kernel methods. Experimental results show a 40x speedup of AP using our representation without degradation in clustering performance. JA - Proceedings of the 23rd international conference on Supercomputing T3 - ICS '09 PB - ACM CY - Yorktown Heights, NY, USA SN - 978-1-60558-498-0 M3 - 10.1145/1542275.1542355 ER - TY - CONF T1 - Arabic Cross-Document Coreference Resolution T2 - Proceedings of the ACL-IJCNLP 2009 Conference Short Papers$}$ Y1 - 2009 A1 - Sayeed,A. A1 - Elsayed,T. A1 - Garera,N. A1 - Alexander,D. A1 - Xu,T. A1 - Oard, Douglas A1 - Yarowsky,D. A1 - Piatko,C. JA - Proceedings of the ACL-IJCNLP 2009 Conference Short Papers$}$ ER - TY - JOUR T1 - An architectural level design methodology for smart camera applications JF - International Journal of Embedded Systems Y1 - 2009 A1 - Saha,S. A1 - Kianzad,V. A1 - Schlessman,J. A1 - Aggarwal,G. A1 - Bhattacharyya, Shuvra S. A1 - Chellapa, Rama A1 - Wolf,W. AB - Today's embedded computing applications are characterised by increased functionality, and hence increased design complexity and processing requirements. The resulting design spaces are vast and designers are typically able to evaluate only small subsets of solutions due to lack of efficient design tools. In this paper, we propose an architectural level design methodology that provides a means for a comprehensive design space exploration for smart camera applications and enable designers to select higher quality solutions and provides substantial savings on the overall cost of the system. We present efficient, accurate and intuitive models for performance estimation and validate them with experiments. VL - 4 CP - 1 ER - TY - CONF T1 - Attacking cryptographic schemes based on "perturbation polynomials" T2 - Proceedings of the 16th ACM conference on Computer and communications security Y1 - 2009 A1 - Albrecht,Martin A1 - Gentry,Craig A1 - Halevi,Shai A1 - Katz, Jonathan KW - pairwise key establishment KW - random perturbation polynomial KW - sensor network security AB - We show attacks on several cryptographic schemes that have recently been proposed for achieving various security goals in sensor networks. Roughly speaking, these schemes all use "perturbation polynomials" to add "noise" to polynomialbased systems that offer information-theoretic security, in an attempt to increase the resilience threshold while maintaining efficiency. We show that the heuristic security arguments given for these modified schemes do not hold, and that they can be completely broken once we allow even a slight extension of the parameters beyond those achieved by the underlying information-theoretic schemes. Our attacks apply to the key predistribution scheme of Zhang et al. (MobiHoc 2007), the access-control schemes of Subramanian et al. (PerCom 2007), and the authentication schemes of Zhang et al. (INFOCOM 2008). Our results cast doubt on the viability of using "perturbation polynomials" for designing secure cryptographic schemes. JA - Proceedings of the 16th ACM conference on Computer and communications security T3 - CCS '09 PB - ACM CY - New York, NY, USA SN - 978-1-60558-894-0 UR - http://doi.acm.org/10.1145/1653662.1653664 M3 - 10.1145/1653662.1653664 ER - TY - JOUR T1 - Characterization and control of pin diameter during in-mold assembly of mesoscale revolute joints JF - North American Manufacturing Research Institute Y1 - 2009 A1 - Ananthanarayanan,A. A1 - Gupta,S.K. A1 - Bruck,H. A. AB - Macro-scale revolute joints can be formed byfirst molding the hole and then molding the pin inside the hole. As the pin shrinks during the solidification process, it moves away from the hole and provides the clearance for the joint to function. The value of clearance in the macro- scale joint can be controlled by carefully selecting the process parameters and the material for the pin. However, in order for this strategy to work at the mesoscale, it requires the use of very thin cores to form sub-millimeter holes. Such thin cores are very difficult to make, are easily damaged during the molding process, and very difficult to retract from the hole. Our previous work has shown that making the pins first and then creating holes on the top of pins leads to successful mesoscale joints. This strategy is counter intuitive based on our experiences at the macro-scale. At the macroscale, as the hole shrinks on top of the pin, the joint is jammed. So a fundamental question is why this counter-intuitive strategy works at the mesoscale. In this paper we show that at the mesoscale, the joint jamming is prevented because of the deformation of the pin under the compressive loading during the second stage molding. We also describe features in the mold that can control the pin deformation and hence control the joint parameters. We present experimental data and computational models to show how mesoscale revolute joints can be formed. VL - 37 UR - http://web.mit.edu/arvinda/www/NAMRI_2009_draft.pdf ER - TY - CONF T1 - Characterizing VLAN-induced sharing in a campus network T2 - Proceedings of the 9th ACM SIGCOMM conference on Internet measurement conference Y1 - 2009 A1 - Bin Tariq,Mukarram A1 - Mansy,Ahmed A1 - Feamster, Nick A1 - Ammar,Mostafa KW - network diagnosis KW - network virtualization KW - VLAN KW - vlan-induced dependency AB - Many enterprise, campus, and data-center networks have complex layer-2 virtual LANs ("VLANs") below the IP layer. The interaction between layer-2 and IP topologies in these VLANs introduces hidden dependencies between IP level network and the physical infrastructure that has implications for network management tasks such as planning for capacity or reliability, and for fault diagnosis. This paper characterizes the extent and effect of these dependencies in a large campus network. We first present the design and implementation of EtherTrace, a tool that we make publicly available, which infers the layer-2 topology using data passively collected from Ethernet switches. Using this tool, we infer the layer-2 topology for a large campus network and compare it with the IP topology. We find that almost 70% of layer-2 edges are shared by 10 or more IP edges, and a single layer-2 edge may be shared by as many as 34 different IP edges. This sharing of layer-2 edges and switches among IP paths commonly results from trunking multiple VLANs to the same access router, or from colocation of academic departments that share layer-2 infrastructure, but have logically separate IP subnet and routers. We examine how this sharing affects the accuracy and specificity of fault diagnosis. For example, applying network tomography to the IP topology to diagnose failures caused by layer-2 devices results in only 54% accuracy, compared to 100% accuracy when our tomography algorithm takes input across layers. JA - Proceedings of the 9th ACM SIGCOMM conference on Internet measurement conference T3 - IMC '09 PB - ACM CY - New York, NY, USA SN - 978-1-60558-771-4 UR - http://doi.acm.org/10.1145/1644893.1644907 M3 - 10.1145/1644893.1644907 ER - TY - CONF T1 - Clutter Noise Removal in Binary Document Images T2 - International Conference on Document Analysis and Recognition (ICDAR '09) Y1 - 2009 A1 - Agrawal,Mudit A1 - David Doermann AB - The paper presents a clutter detection and removal algorithm for complex document images. The distance transform based approach is independent of clutter's position, size, shape and connectivity with text. Features are based on a new technique called `nth erosion' and clutter elements are identified with an SVM classifier. Removal is restrictive, so text attached to the clutter is not deleted in the process. The method was tested on a mix of degraded and noisy, machine-printed and handwritten Arabic and English text documents. Results show pixel-level accuracies of 97.5% and 95% for clutter detection and removal respectively. This approach was also extended with a noise detection and removal model for documents having a mix of clutter and salt-n-pepper noise. JA - International Conference on Document Analysis and Recognition (ICDAR '09) ER - TY - JOUR T1 - Collusion-free multiparty computation in the mediated model JF - Advances in Cryptology-CRYPTO 2009 Y1 - 2009 A1 - Alwen,J. A1 - Katz, Jonathan A1 - Lindell,Y. A1 - Persiano,G. A1 - Shelat,A. A1 - Visconti,I. AB - Collusion-free protocols prevent subliminal communication (i.e., covert channels) between parties running the protocol. In the standard communication model, if one-way functions exist, then protocols satisfying any reasonable degree of privacy cannot be collusion-free. To circumvent this impossibility, Alwen, shelat and Visconti (CRYPTO 2008) recently suggested the mediated model where all communication passes through a mediator. The goal is to design protocols where collusion-freeness is guaranteed as long as the mediator is honest, while standard security guarantees hold if the mediator is dishonest. In this model, they gave constructions of collusion-free protocols for commitments and zero-knowledge proofs in the two-party setting.We strengthen the definition of Alwen et al., and resolve the main open questions in this area by showing a collusion-free protocol (in the mediated model) for computing any multi-party functionality. M3 - 10.1007/978-3-642-03356-8_31 ER - TY - JOUR T1 - Computational linguistics for metadata building (CLiMB): using text mining for the automatic identification, categorization, and disambiguation of subject terms for image metadata JF - Multimedia Tools and Applications Y1 - 2009 A1 - Klavans,J. L A1 - Sheffield,C. A1 - Abels,E. A1 - Jimmy Lin A1 - Passonneau,R. A1 - Sidhu,T. A1 - Soergel,D. AB - In this paper, we present a system using computational linguistic techniques to extract metadata for image access. We discuss the implementation, functionality and evaluation of an image catalogers’ toolkit, developed in the Computational Linguistics for Metadata Building (CLiMB) research project. We have tested components of the system, including phrase finding for the art and architecture domain, functional semantic labeling using machine learning, and disambiguation of terms in domain-specific text vis a vis a rich thesaurus of subject terms, geographic and artist names. We present specific results on disambiguation techniques and on the nature of the ambiguity problem given the thesaurus, resources, and domain-specific text resource, with a comparison of domain-general resources and text. Our primary user group for evaluation has been the cataloger expert with specific expertise in the fields of painting, sculpture, and vernacular and landscape architecture. VL - 42 CP - 1 M3 - 10.1007/s11042-008-0253-9 ER - TY - CONF T1 - Cross-document coreference resolution: A key technology for learning by reading T2 - AAAI Spring Symposium on Learning by Reading and Learning to Read Y1 - 2009 A1 - Mayfield,J. A1 - Alexander,D. A1 - Dorr, Bonnie J A1 - Eisner,J. A1 - Elsayed,T. A1 - Finin,T. A1 - Fink,C. A1 - Freedman,M. A1 - Garera,N. A1 - McNamee,P. A1 - others JA - AAAI Spring Symposium on Learning by Reading and Learning to Read ER - TY - JOUR T1 - CTCF binding site classes exhibit distinct evolutionary, genomic, epigenomic and transcriptomic features JF - Genome Biology Y1 - 2009 A1 - Essien,Kobby A1 - Vigneau,Sebastien A1 - Apreleva,Sofia A1 - Singh,Larry N. A1 - Bartolomei,Marisa S. A1 - Hannenhalli, Sridhar AB - CTCF (CCCTC-binding factor) is an evolutionarily conserved zinc finger protein involved in diverse functions ranging from negative regulation of MYC, to chromatin insulation of the beta-globin gene cluster, to imprinting of the Igf2 locus. The 11 zinc fingers of CTCF are known to differentially contribute to the CTCF-DNA interaction at different binding sites. It is possible that the differences in CTCF-DNA conformation at different binding sites underlie CTCF's functional diversity. If so, the CTCF binding sites may belong to distinct classes, each compatible with a specific functional role. VL - 10 SN - 1465-6906 UR - http://genomebiology.com/2009/10/11/R131 CP - 11 M3 - 10.1186/gb-2009-10-11-r131 ER - TY - CONF T1 - Detecting network neutrality violations with causal inference T2 - Proceedings of the 5th international conference on Emerging networking experiments and technologies Y1 - 2009 A1 - Bin Tariq,Mukarram A1 - Motiwala,Murtaza A1 - Feamster, Nick A1 - Ammar,Mostafa KW - causal inference KW - network neutrality AB - We present NANO, a system that detects when ISPs apply policies that discriminate against specific classes of applications, users, or destinations. Existing systems for detecting discrimination are typically specific to an application or to a particular discrimination mechanism and rely on active measurement tests. Unfortunately, ISPs can change discrimination policies and mechanisms, and they can evade these tests by giving probe traffic higher priority. NANO detects ISP discrimination by passively collecting performance data from clients. To distinguish discrimination from other causes of degradation (e.g., overload, misconfiguration, failure), NANO establishes a causal relationship between an ISP and observed performance by adjusting for confounding factors. NANO agents deployed at participating clients across the Internet collect performance data for selected services and report this information to centralized servers, which analyze the measurements to establish causal relationship between an ISP and performance degradations. We have implemented NANO and deployed clients in a controlled environment on Emulab. We run a combination of controlled experiments on Emulab and wide-area experiments on PlanetLab that show that NANO can determine the extent and criteria for discrimination for a variety of discrimination policies and applications. JA - Proceedings of the 5th international conference on Emerging networking experiments and technologies T3 - CoNEXT '09 PB - ACM CY - New York, NY, USA SN - 978-1-60558-636-6 UR - http://doi.acm.org/10.1145/1658939.1658972 M3 - 10.1145/1658939.1658972 ER - TY - JOUR T1 - Diversity and Seasonality of Bioluminescent Vibrio Cholerae Populations in Chesapeake Bay JF - Applied and Environmental MicrobiologyAppl. Environ. Microbiol. Y1 - 2009 A1 - Zo,Young-Gun A1 - Chokesajjawatee,Nipa A1 - Grim,Christopher A1 - Arakawa,Eiji A1 - Watanabe,Haruo A1 - Rita R Colwell AB - Association of luminescence with phenotypic and genotypic traits and with environmental parameters was determined for 278 strains of Vibrio cholerae isolated from the Chesapeake Bay during 1998 to 2000. Three clusters of luminescent strains (A, B, and C) and two nonluminescent clusters (X and Y) were identified among 180 clonal types. V. cholerae O1 strains isolated during pandemics and endemic cholera in the Ganges Delta were related to cluster Y. Heat-stable enterotoxin (encoded by stn) and the membrane protein associated with bile resistance (encoded by ompU) were found to be linked to luminescence in strains of cluster A. Succession from nonluminescent to luminescent populations of V. cholerae occurred during spring to midsummer. Occurrence of cluster A strains in water with neutral pH was contrasted with that of cluster Y strains in water with a pH of >8. Cluster A was found to be associated with a specific calanoid population cooccurring with cyclopoids. Cluster B was related to cluster Y, with its maximal prevalence at pH 8. Occurrence of cluster B strains was more frequent with warmer water temperatures and negatively correlated with maturity of the copepod community. It is concluded that each cluster of luminescent V. cholerae strains occupies a distinct ecological niche. Since the dynamics of these niche-specific subpopulations are associated with zooplankton community composition, the ecology of luminescent V. cholerae is concluded to be related to its interaction with copepods and related crustacean species. VL - 75 SN - 0099-2240, 1098-5336 UR - http://aem.asm.org/content/75/1/135 CP - 1 M3 - 10.1128/AEM.02894-07 ER - TY - JOUR T1 - The effect of corners on the complexity of approximate range searching JF - Discrete & Computational Geometry Y1 - 2009 A1 - Arya,S. A1 - Malamatos,T. A1 - Mount, Dave AB - Given an n-element point set in ℝ d , the range searching problem involves preprocessing these points so that the total weight, or for our purposes the semigroup sum, of the points lying within a given query range η can be determined quickly. In ε-approximate range searching we assume that η is bounded, and the sum is required to include all the points that lie within η and may additionally include any of the points lying within distance ε⋅diam(η) of η’s boundary.In this paper we contrast the complexity of approximate range searching based on properties of the semigroup and range space. A semigroup (S,+) is idempotent if x+x=x for all x∈S, and it is integral if for all k≥2, the k-fold sum x+⋅⋅⋅+x is not equal to x. Recent research has shown that the computational complexity of approximate spherical range searching is significantly lower for idempotent semigroups than it is for integral semigroups in terms of the dependencies on ε. In this paper we consider whether these results can be generalized to other sorts of ranges. We show that, as with integrality, allowing sharp corners on ranges has an adverse effect on the complexity of the problem. In particular, we establish lower bounds on the worst-case complexity of approximate range searching in the semigroup arithmetic model for ranges consisting of d-dimensional unit hypercubes under rigid motions. We show that for arbitrary (including idempotent) semigroups and linear space, the query time is at least \varOmega(1/{\varepsilon }^{d-2\sqrt{d}}) . In the case of integral semigroups we prove a tighter lower bound of Ω(1/ε d−2). These lower bounds nearly match existing upper bounds for arbitrary semigroups. In contrast, we show that the improvements offered by idempotence do apply to smooth convex ranges. We say that a range is smooth if at every boundary point there is an incident Euclidean sphere that lies entirely within the range whose radius is proportional to the range’s diameter. We show that for smooth ranges and idempotent semigroups, ε-approximate range queries can be answered in O(log n+(1/ε)(d−1)/2log (1/ε)) time using O(n/ε) space. We show that this is nearly tight by presenting a lower bound of Ω(log n+(1/ε)(d−1)/2). This bound is in the decision-tree model and holds irrespective of space. VL - 41 CP - 3 M3 - 10.1007/s00454-009-9140-z ER - TY - CONF T1 - Efficient band approximation of Gram matrices for large scale kernel methods on GPUs T2 - Proceedings of the Conference on High Performance Computing Networking, Storage and Analysis Y1 - 2009 A1 - Hussein,Mohamed A1 - Abd-Almageed, Wael KW - affinity propagation KW - algorithms KW - gpu AB - Kernel-based methods require O(N2) time and space complexities to compute and store non-sparse Gram matrices, which is prohibitively expensive for large scale problems. We introduce a novel method to approximate a Gram matrix with a band matrix. Our method relies on the locality preserving properties of space filling curves, and the special structure of Gram matrices. Our approach has several important merits. First, it computes only those elements of the Gram matrix that lie within the projected band. Second, it is simple to parallelize. Third, using the special band matrix structure makes it space efficient and GPU-friendly. We developed GPU implementations for the Affinity Propagation (AP) clustering algorithm using both our method and the COO sparse representation. Our band approximation is about 5 times more space efficient and faster to construct than COO. AP gains up to 6x speedup using our method without any degradation in its clustering performance. JA - Proceedings of the Conference on High Performance Computing Networking, Storage and Analysis T3 - SC '09 PB - ACM CY - Portland, Oregon SN - 978-1-60558-744-8 M3 - 10.1145/1654059.1654091 ER - TY - JOUR T1 - Efficient peer-to-Peer lookup in multi-hop wireless networks JF - KSII Trans. Internet and Information Systems Y1 - 2009 A1 - Shin,M. A1 - Arbaugh, William A. VL - 3 CP - 1 ER - TY - CHAP T1 - Efficient Robust Private Set Intersection T2 - Applied Cryptography and Network Security Y1 - 2009 A1 - Dana Dachman-Soled A1 - Malkin, Tal A1 - Raykova, Mariana A1 - Yung, Moti ED - Abdalla, Michel ED - Pointcheval, David ED - Fouque, Pierre-Alain ED - Vergnaud, Damien KW - Coding and Information Theory KW - Computer Communication Networks KW - Cryptographic protocols KW - Data Encryption KW - Data Structures, Cryptology and Information Theory KW - Information Systems Applications (incl.Internet) KW - Privacy Preserving Data Mining KW - Secure Two-party Computation KW - Set Intersection KW - Systems and Data Security AB - Computing Set Intersection privately and efficiently between two mutually mistrusting parties is an important basic procedure in the area of private data mining. Assuring robustness, namely, coping with potentially arbitrarily misbehaving (i.e., malicious) parties, while retaining protocol efficiency (rather than employing costly generic techniques) is an open problem. In this work the first solution to this problem is presented. JA - Applied Cryptography and Network Security T3 - Lecture Notes in Computer Science PB - Springer Berlin Heidelberg SN - 978-3-642-01956-2, 978-3-642-01957-9 UR - http://link.springer.com/chapter/10.1007/978-3-642-01957-9_8 ER - TY - CONF T1 - Enforcing integrability by error correction using ℓ1-minimization T2 - Computer Vision and Pattern Recognition, 2009. CVPR 2009. IEEE Conference on Y1 - 2009 A1 - Reddy, D. A1 - Agrawal,A. A1 - Chellapa, Rama KW - - KW - algebra;lscr0 KW - algebra;minimisation; KW - analogy;integrability;least KW - compressed KW - correction;gradient KW - equivalence;lscr1-minimization;noise-outlier;surface KW - estimation;gradient KW - field KW - integration;gradient KW - lscr1 KW - manipulation;graph KW - methods;graph KW - reconstruction;error KW - reconstruction;linear KW - sensing;error KW - squares;linear KW - theory;image AB - Surface reconstruction from gradient fields is an important final step in several applications involving gradient manipulations and estimation. Typically, the resulting gradient field is non-integrable due to linear/non-linear gradient manipulations, or due to presence of noise/outliers in gradient estimation. In this paper, we analyze integrability as error correction, inspired from recent work in compressed sensing, particulary lscr0 - lscr1 equivalence. We propose to obtain the surface by finding the gradient field which best fits the corrupted gradient field in lscr1 sense. We present an exhaustive analysis of the properties of lscr1 solution for gradient field integration using linear algebra and graph analogy. We consider three cases: (a) noise, but no outliers (b) no-noise but outliers and (c) presence of both noise and outliers in the given gradient field. We show that lscr1 solution performs as well as least squares in the absence of outliers. While previous lscr0 - lscr1 equivalence work has focused on the number of errors (outliers), we show that the location of errors is equally important for gradient field integration. We characterize the lscr1 solution both in terms of location and number of outliers, and outline scenarios where lscr1 solution is equivalent to lscr0 solution. We also show that when lscr1 solution is not able to remove outliers, the property of local error confinement holds: i.e., the errors do not propagate to the entire surface as in least squares. We compare with previous techniques and show that lscr1 solution performs well across all scenarios without the need for any tunable parameter adjustments. JA - Computer Vision and Pattern Recognition, 2009. CVPR 2009. IEEE Conference on M3 - 10.1109/CVPR.2009.5206603 ER - TY - CONF T1 - Exponential family hybrid semi-supervised learning T2 - Proceedings of the 21st International Joint Conference on Artifical Intelligence (IJCAI-09) Y1 - 2009 A1 - Agarwal,A. A1 - Daumé, Hal JA - Proceedings of the 21st International Joint Conference on Artifical Intelligence (IJCAI-09) ER - TY - CHAP T1 - Face Recognition from Video T2 - The Essential Guide to Video Processing (Second Edition)The Essential Guide to Video Processing (Second Edition) Y1 - 2009 A1 - Zhou,Shaohua Kevin A1 - Chellapa, Rama A1 - Aggarwal,Gaurav ED - Al Bovik JA - The Essential Guide to Video Processing (Second Edition)The Essential Guide to Video Processing (Second Edition) PB - Academic Press CY - Boston SN - 978-0-12-374456-2 UR - http://www.sciencedirect.com/science/article/pii/B9780123744562000232 ER - TY - JOUR T1 - A Fast, Virtualized Data Plane for the NetFPGA JF - NetFPGA Developers Workshop, Stanford, California Y1 - 2009 A1 - Anwer,M.B. A1 - Feamster, Nick AB - Network virtualization allows many networks to share thesame underlying physical topology; this technology has of- fered promise both for experimentation and for hosting mul- tiple networks on a single shared physical infrastructure. Much attention has focused on virtualizing the network con- trol plane, but, ultimately, a limiting factor in the deployment of these virtual networks is data-plane performance: Virtual networks must ultimately forward packets at rates that are comparable to native, hardware-based approaches. Aside from proprietary solutions from vendors, hardware support for virtualized data planes is limited. The advent of open, programmable network hardware promises flexibility, speed, and resource isolation, but, unfortunately, hardware does not naturally lend itself to virtualization. We leverage emerg- ing trends in programmable hardware to design a flexible, hardware-based data plane for virtual networks. We present the design, implementation, and preliminary evaluation of this hardware-based data plane and show how the proposed design can support many virtual networks without compro- mising performance or isolation. ER - TY - JOUR T1 - Image Transformations and Blurring JF - IEEE Transactions on Pattern Analysis and Machine Intelligence Y1 - 2009 A1 - Domke, Justin A1 - Aloimonos, J. KW - reconstruction KW - restoration KW - sharpening and deblurring KW - smoothing. AB - Since cameras blur the incoming light during measurement, different images of the same surface do not contain the same information about that surface. Thus, in general, corresponding points in multiple views of a scene have different image intensities. While multiple-view geometry constrains the locations of corresponding points, it does not give relationships between the signals at corresponding locations. This paper offers an elementary treatment of these relationships. We first develop the notion of "ideal” and "real” images, corresponding to, respectively, the raw incoming light and the measured signal. This framework separates the filtering and geometric aspects of imaging. We then consider how to synthesize one view of a surface from another; if the transformation between the two views is affine, it emerges that this is possible if and only if the singular values of the affine matrix are positive. Next, we consider how to combine the information in several views of a surface into a single output image. By developing a new tool called "frequency segmentation,” we show how this can be done despite not knowing the blurring kernel. VL - 31 SN - 0162-8828 CP - 5 M3 - http://doi.ieeecomputersociety.org/10.1109/TPAMI.2008.133 ER - TY - CONF T1 - Improved approximation algorithms for prize-collecting Steiner tree and TSP T2 - 2009 50th Annual IEEE Symposium on Foundations of Computer Science Y1 - 2009 A1 - Archer,A. A1 - Bateni,M. H A1 - Hajiaghayi, Mohammad T. A1 - Karloff,H. JA - 2009 50th Annual IEEE Symposium on Foundations of Computer Science ER - TY - JOUR T1 - Integrated product and process design for a flapping wing drive mechanism JF - Journal of Mechanical Design Y1 - 2009 A1 - Bejgerowski,W. A1 - Ananthanarayanan,A. A1 - Mueller,D. A1 - Gupta,S.K. VL - 131 ER - TY - CONF T1 - Interacting with eHealth: towards grand challenges for HCI T2 - Proceedings of the 27th international conference extended abstracts on Human factors in computing systems Y1 - 2009 A1 - André,P. A1 - White,R. A1 - Tan,D. A1 - Berners-Lee,T. A1 - Consolvo,S. A1 - Jacobs,R. A1 - Kohane,I. A1 - Le Dantec,C.A. A1 - Mamykina,L. A1 - Marsden,G. AB - While health records are increasingly stored electronically, we, as citizens, have little access to this data about ourselves. We are not used to thinking of these official records either as ours or as useful to us. We increasingly turn to the Web, however, to query any ache, pain or health goal we may have before consulting with health care professionals. Likewise, for proactive health care such as nutrition or fitness, or to find fellow-sufferers for post diagnosis support, we turn to online resources. There is a potential disconnect between points at which professional and lay eHealth data and resources intersect for preventative or proactive health care. Such gaps in information sharing may have direct impact on practices we decide to take up, the care we seek, or the support professionals offer. In this panel, we consider several places within proactive, preventative health care in particular HCI has a role towards enhancing health knowledge discovery and health support interaction. Our goal is to demonstrate how now is the time for eHealth to come to the forefront of the HCI research agenda. JA - Proceedings of the 27th international conference extended abstracts on Human factors in computing systems ER - TY - JOUR T1 - MEASURING 1ST ORDER STRETCH WITH A SINGLE FILTER JF - Relation Y1 - 2009 A1 - Bitsakos,K. A1 - Domke, J. A1 - Fermüller, Cornelia A1 - Aloimonos, J. AB - We analytically develop a filter that is able to measurethe linear stretch of the transformation around a point, and present results of applying it to real signals. We show that this method is a real-time alternative solution for measuring local signal transformations. Experimentally, this method can accurately measure stretch, however, it is sensitive to shift. VL - 10 CP - 1.132 ER - TY - CONF T1 - Measuring General Relational Structure Using the Block Modularity Clustering Objective T2 - Twenty-Second International FLAIRS Conference Y1 - 2009 A1 - Anthony,Adam Paul A1 - desJardins, Marie A1 - Lombardi,Michael AB - The performance of all relational learning techniques has an implicit dependence on the underlying connectivity structure of the relations that are used as input. In this paper, we show how clustering can be used to develop an efficient optimization strategy can be used to effectively measure the structure of a graph in the absence of labeled instances. JA - Twenty-Second International FLAIRS Conference UR - http://www.aaai.org/ocs/index.php/FLAIRS/2009/paper/viewPaper/46 ER - TY - CONF T1 - Measuring vlan-induced dependencies on a campus network T2 - Proceedings of the ACM SIGCOMM Internet measurement conference Y1 - 2009 A1 - Mansy,A. A1 - Tariq,M.B. A1 - Feamster, Nick A1 - Ammar,M. AB - Many enterprise, campus, and data-center networks have complexlayer-2 virtual LANs (“VLANs”) underlying the layer-3 network. The interac- tion between layer-2 and layer-3 topologies can introduce dependencies that are not visible when analyzed solely from layer 3; this paper studies the extent and impact of these dependencies. We first present EtherTrace, a tool that infers the layer-2 topology using data passively collected from Ethernet switches. Using this tool, we infer the layer-2 topology for a large campus network and compare the two topologies. Our comparison yields some striking initial findings: almost 70% of layer-2 edges are shared by 10 or more IP edges, and a single layer-2 edge may be shared by as many as 34 different IP edges. This sharing has significant implications for both robustness and for network tomography. Applying network tomography to the IP topology to diagnose failures caused by layer-2 devices results in only 54% accuracy, compared to 100% accuracy when tomography is performed at layer 2. JA - Proceedings of the ACM SIGCOMM Internet measurement conference ER - TY - CONF T1 - Modal expansion of HRTFs: Continuous representation in frequency-range-angle T2 - Acoustics, Speech and Signal Processing, 2009. ICASSP 2009. IEEE International Conference on Y1 - 2009 A1 - Zhang,Wen A1 - Abhayapala,T.D. A1 - Kennedy,R.A. A1 - Duraiswami, Ramani KW - analysis;signal KW - bessel KW - domains;frequency-range-angle;head KW - expansion;modal KW - Fourier KW - function;modal KW - functions; KW - reconstruction;signal KW - related KW - representation;transfer KW - series;HRTF;frequency KW - spherical KW - transfer AB - This paper proposes a continuous HRTF representation in both 3D spatial and frequency domains. The method is based on the acoustic reciprocity principle and a modal expansion of the wave equation solution to represent the HRTF variations with different variables in separate basis functions. The derived spatial basis modes can achieve HRTF near-field and far-field representation in one formulation. The HRTF frequency components are expanded using Fourier Spherical Bessel series for compact representation. The proposed model can be used to reconstruct HRTFs at any arbitrary position in space and at any frequency point from a finite number of measurements. Analytical simulated and measured HRTFs from a KEMAR are used to validate the model. JA - Acoustics, Speech and Signal Processing, 2009. ICASSP 2009. IEEE International Conference on M3 - 10.1109/ICASSP.2009.4959576 ER - TY - RPRT T1 - A Narrow Waist for Multipath Routing Y1 - 2009 A1 - Motiwala,M. A1 - bin Tariq,M. A1 - Anwer,B. A1 - Andersen,D. A1 - Feamster, Nick AB - Many applications can use multipath routing to improvereliability or throughput, and many multipath routing pro- tocols exist. Despite this diversity of mechanisms and applications, no common interface exists to allow an ap- plication to select these paths. This paper presents a de- sign for such a common interface, called path bits. Path bits are a small string of opaque, semantic-free bits in a packet header; these bits have a simple property: changing a packet’s path bits should, with high probability, result in the packet taking a different path to the destination. This paper presents the design of path bits and demonstrates that they are simple enough to be easily implemented in both hardware and software and expressive enough to sup- port a variety of applications that can benefit from mul- tipath routing. We present both hardware and software implementations of multipath routing protocols that im- plement the path bits abstraction, as well as implementa- tions of applications that can use this abstraction with only small modifications. PB - School of Computer Science, Georgia Tech ER - TY - JOUR T1 - New records of phytoplankton for Bangladesh. 9. Some rare and a new species JF - Bangladesh Journal of Plant Taxonomy Y1 - 2009 A1 - Khondker,Moniruzzaman A1 - Bhuiyan,Rauf Ahmed A1 - Yeasmin,Jenat A1 - Alam,Munirul A1 - Sack,R. Bradley A1 - Huq,Anwar A1 - Rita R Colwell AB - Ten taxa belonging to Chlorophyceae, Cyanophyceae, Bacillariophyceae and Euglenophyceae, and one with an uncertain taxonomic position have been described in this paper. Of these, 10 taxa have been found to be globally rare and new records for Bangladesh, whereas Strombomonas islamii Khondker sp. nov. has been described as new to science. VL - 16 SN - 1028-2092 UR - http://www.banglajol.info/bd/index.php/BJPT/article/viewArticle/2734 CP - 1 M3 - 10.3329/bjpt.v16i1.2734 ER - TY - CONF T1 - Online allocation of display advertisements subject to advanced sales contracts T2 - Proceedings of the Third International Workshop on Data Mining and Audience Intelligence for Advertising Y1 - 2009 A1 - Alaei,Saeed A1 - Arcaute,Esteban A1 - Khuller, Samir A1 - Ma,Wenjing A1 - Malekian,Azarakhsh A1 - Tomlin,John KW - display advertising KW - modeling KW - online algorithms KW - OPTIMIZATION KW - simulation AB - In this paper we propose a utility model that accounts for both sales and branding advertisers. We first study the computational complexity of optimization problems related to both online and offline allocation of display advertisements. Next, we focus on a particular instance of the online allocation problem, and design a simple online algorithm with provable approximation guarantees. Our algorithm is near optimal as is shown by a matching lower bound. Finally, we report on experiments to establish actual case behavior on some real datasets, with encouraging results. JA - Proceedings of the Third International Workshop on Data Mining and Audience Intelligence for Advertising T3 - ADKDD '09 PB - ACM CY - New York, NY, USA SN - 978-1-60558-671-7 UR - http://doi.acm.org/10.1145/1592748.1592758 M3 - 10.1145/1592748.1592758 ER - TY - CONF T1 - Page Rule-Line Removal using Linear Subspaces in Monochromatic Handwritten Arabic Documents T2 - Intl. Conf. on Document Analysis and Recognition (ICDAR 09) Y1 - 2009 A1 - Abd-Almageed, Wael A1 - Kumar,Jayant A1 - David Doermann AB - In this paper we present a novel method for removing page rule lines in monochromatic handwritten Arabic documents using subspace methods with minimal effect on the quality of the foreground text. We use moment and histogram properties to extract features that represent the characteristics of the underlying rule lines. A linear subspace is incrementally built to obtain a line model that can be used to identify rule line pixels. We also introduce a novel scheme for evaluating noise removal algorithms in general and we use it to assess the quality of our rule line removal algorithm. Experimental results presented on a data set of 50 Arabic documents, handwritten by different writers, demonstrate the effectiveness of the proposed method. JA - Intl. Conf. on Document Analysis and Recognition (ICDAR 09) ER - TY - JOUR T1 - Path oracles for spatial networks JF - Proc. VLDB Endow. Y1 - 2009 A1 - Sankaranarayanan,Jagan A1 - Samet, Hanan A1 - Alborzi,Houman AB - The advent of location-based services has led to an increased demand for performing operations on spatial networks in real time. The challenge lies in being able to cast operations on spatial networks in terms of relational operators so that they can be performed in the context of a database. A linear-sized construct termed a path oracle is introduced that compactly encodes the n2 shortest paths between every pair of vertices in a spatial network having n vertices thereby reducing each of the paths to a single tuple in a relational database and enables finding shortest paths by repeated application of a single SQL SELECT operator. The construction of the path oracle is based on the observed coherence between the spatial positions of both source and destination vertices and the shortest paths between them which facilitates the aggregation of source and destination vertices into groups that share common vertices or edges on the shortest paths between them. With the aid of the Well-Separated Pair (WSP) technique, which has been applied to spatial networks using the network distance measure, a path oracle is proposed that takes O(sdn) space, where s is empirically estimated to be around 12 for road networks, but that can retrieve an intermediate link in a shortest path in O(logn) time using a B-tree. An additional construct termed the path-distance oracle of size O(n · max(sd, 1/εd)) (empirically (n · max(122, 2.5/ε2))) is proposed that can retrieve an intermediate vertex as well as an ε-approximation of the network distances in O(logn) time using a B-tree. Experimental results indicate that the proposed oracles are linear in n which means that they are scalable and can enable complicated query processing scenarios on massive spatial network datasets. VL - 2 SN - 2150-8097 UR - http://dl.acm.org/citation.cfm?id=1687627.1687763 CP - 1 ER - TY - CHAP T1 - Planning for Interactions among Autonomous Agents T2 - Programming Multi-Agent Systems Y1 - 2009 A1 - Au,Tsz-Chiu A1 - Kuter,Ugur A1 - Nau, Dana S. ED - Hindriks,Koen ED - Pokahr,Alexander ED - Sardina,Sebastian KW - Computer science AB - AI planning research has traditionally focused on offline pl- anning for static single-agent environments. In environments where an agent needs to plan its interactions with other autonomous agents, planning is much more complicated, because the actions of the other agents can induce a combinatorial explosion in the number of contingencies that the planner will need to consider. This paper discusses several ways to alleviate the combinatorial explosion, and illustrates their use in several different kinds of multi-agent planning domains. JA - Programming Multi-Agent Systems T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 5442 SN - 978-3-642-03277-6 UR - http://www.springerlink.com/content/j258015ux2p38383/abstract/ ER - TY - JOUR T1 - Profile-guided static typing for dynamic scripting languages JF - ACM SIGPLAN Notices Y1 - 2009 A1 - Furr,M. A1 - An,J.D. A1 - Foster, Jeffrey S. VL - 44 CP - 10 ER - TY - JOUR T1 - Proofs of storage from homomorphic identification protocols JF - Advances in Cryptology–ASIACRYPT 2009 Y1 - 2009 A1 - Ateniese,G. A1 - Kamara,S. A1 - Katz, Jonathan AB - Proofs of storage (PoS) are interactive protocols allowing a client to verify that a server faithfully stores a file. Previous work has shown that proofs of storage can be constructed from any homomorphic linear authenticator (HLA). The latter, roughly speaking, are signature/message authentication schemes where ‘tags’ on multiple messages can be homomorphically combined to yield a ‘tag’ on any linear combination of these messages.We provide a framework for building public-key HLAs from any identification protocol satisfying certain homomorphic properties. We then show how to turn any public-key HLA into a publicly-verifiable PoS with communication complexity independent of the file length and supporting an unbounded number of verifications. We illustrate the use of our transformations by applying them to a variant of an identification protocol by Shoup, thus obtaining the first unbounded-use PoS based on factoring (in the random oracle model). M3 - 10.1007/978-3-642-10366-7_19 ER - TY - CONF T1 - On random sampling auctions for digital goods T2 - Proceedings of the 10th ACM conference on Electronic commerce Y1 - 2009 A1 - Alaei,Saeed A1 - Malekian,Azarakhsh A1 - Srinivasan, Aravind KW - auction KW - mechanism design KW - random sampling AB - In the context of auctions for digital goods, an interesting Random Sampling Optimal Price auction (RSOP) has been proposed by Goldberg, Hartline and Wright; this leads to a truthful mechanism. Since random sampling is a popular approach for auctions that aims to maximize the seller's revenue, this method has been analyzed further by Feige, Flaxman, Hartline and Kleinberg, who have shown that it is 15-competitive in the worst case -- which is substantially better than the previously proved bounds but still far from the conjectured competitive ratio of 4. In this paper, we prove that RSOP is indeed 4-competitive for a large class of instances in which the number λ of bidders receiving the item at the optimal uniform price, is at least 6. We also show that it is 4.68 competitive for the small class of remaining instances thus leaving a negligible gap between the lower and upper bound. Furthermore, we develop a robust version of RSOP -- one in which the seller's revenue is, with high probability, not much below its mean -- when the above parameter λ grows large. We employ a mix of probabilistic techniques and dynamic programming to compute these bounds. JA - Proceedings of the 10th ACM conference on Electronic commerce T3 - EC '09 PB - ACM CY - New York, NY, USA SN - 978-1-60558-458-4 UR - http://doi.acm.org/10.1145/1566374.1566402 M3 - 10.1145/1566374.1566402 ER - TY - CONF T1 - Real-time shape retrieval for robotics using skip Tri-Grams T2 - IEEE/RSJ International Conference on Intelligent Robots and Systems, 2009. IROS 2009 Y1 - 2009 A1 - Li,Yi A1 - Bitsakos,K. A1 - Fermüller, Cornelia A1 - Aloimonos, J. KW - Bullseye retrieval test KW - Clocks KW - closed contour shape retrieval KW - Image retrieval KW - Image segmentation KW - Indexing KW - Information retrieval KW - Intelligent robots KW - Jacobian matrices KW - mobile robot KW - Mobile robots KW - MPEG 7 shape dataset KW - piecewise linear segments KW - Piecewise linear techniques KW - Real time systems KW - real-time shape retrieval KW - robot vision KW - SHAPE KW - shape recognition KW - shape representation KW - skip Tri-Grams KW - Testing AB - The real time requirement is an additional constraint on many intelligent applications in robotics, such as shape recognition and retrieval using a mobile robot platform. In this paper, we present a scalable approach for efficiently retrieving closed contour shapes. The contour of an object is represented by piecewise linear segments. A skip Tri-Gram is obtained by selecting three segments in the clockwise order while allowing a constant number of segments to be ¿skipped¿ in between. The main idea is to use skip Tri-Grams of the segments to implicitly encode the distant dependency of the shape. All skip Tri-Grams are used for efficiently retrieving closed contour shapes without pairwise matching feature points from two shapes. The retrieval is at least an order of magnitude faster than other state-of-the-art algorithms. We score 80% in the Bullseye retrieval test on the whole MPEG 7 shape dataset. We further test the algorithm using a mobile robot platform in an indoor environment. 8 objects are used for testing from different viewing directions, and we achieve 82% accuracy. JA - IEEE/RSJ International Conference on Intelligent Robots and Systems, 2009. IROS 2009 PB - IEEE SN - 978-1-4244-3803-7 M3 - 10.1109/IROS.2009.5354738 ER - TY - CONF T1 - Recovering Views of Inter-System Interaction Behaviors T2 - Reverse Engineering, Working Conference on Y1 - 2009 A1 - Ackermann,Christopher A1 - Lindvall,Mikael A1 - Cleaveland, Rance KW - distributed systems KW - program understanding KW - reliability AB - This paper presents an approach for recovering application-level views of the interaction behaviors between systems that communicate via networks. Rather than illustrating a single behavior, a sequence diagram is constructed that describes the characteristics of multiple combined behaviors. The approach has several properties that make it particularly suitable for analyzing heterogeneous systems. First, since the interactions are retrieved from observing the network communication, our technique can be applied to systems that are implemented in different languages and run on different platforms. Second, it does not require the availability or modification of source code. After the behaviors are extracted, we employ methods to merge multiple observed behaviors to a single sequence diagram that illustrates the overall behavior.The contributions of this paper are a technique for observing and processing the network communication to derive a model of the behavior. Furthermore, it describes a series of model transformations to construct a sequence diagram view of all observed behaviors. JA - Reverse Engineering, Working Conference on PB - IEEE Computer Society CY - Los Alamitos, CA, USA M3 - http://doi.ieeecomputersociety.org/10.1109/WCRE.2009.34 ER - TY - JOUR T1 - RNA Colony Blot Hybridization Method for Enumeration of Culturable Vibrio Cholerae and Vibrio Mimicus Bacteria JF - Applied and Environmental MicrobiologyAppl. Environ. Microbiol. Y1 - 2009 A1 - Grim,Christopher J. A1 - Zo,Young-Gun A1 - Hasan,Nur A. A1 - Ali,Afsar A1 - Chowdhury,Wasimul B. A1 - Islam,Atiqul A1 - Rashid,Mohammed H. A1 - Alam,Munirul A1 - Morris,J. Glenn A1 - Huq,Anwar A1 - Rita R Colwell AB - A species-specific RNA colony blot hybridization protocol was developed for enumeration of culturable Vibrio cholerae and Vibrio mimicus bacteria in environmental water samples. Bacterial colonies on selective or nonselective plates were lysed by sodium dodecyl sulfate, and the lysates were immobilized on nylon membranes. A fluorescently labeled oligonucleotide probe targeting a phylogenetic signature sequence of 16S rRNA of V. cholerae and V. mimicus was hybridized to rRNA molecules immobilized on the nylon colony lift blots. The protocol produced strong positive signals for all colonies of the 15 diverse V. cholerae-V. mimicus strains tested, indicating 100% sensitivity of the probe for the targeted species. For visible colonies of 10 nontarget species, the specificity of the probe was calculated to be 90% because of a weak positive signal produced by Grimontia (Vibrio) hollisae, a marine bacterium. When both the sensitivity and specificity of the assay were evaluated using lake water samples amended with a bioluminescent V. cholerae strain, no false-negative or false-positive results were found, indicating 100% sensitivity and specificity for culturable bacterial populations in freshwater samples when G. hollisae was not present. When the protocol was applied to laboratory microcosms containing V. cholerae attached to live copepods, copepods were found to carry approximately 10,000 to 50,000 CFU of V. cholerae per copepod. The protocol was also used to analyze pond water samples collected in an area of cholera endemicity in Bangladesh over a 9-month period. Water samples collected from six ponds demonstrated a peak in abundance of total culturable V. cholerae bacteria 1 to 2 months prior to observed increases in pathogenic V. cholerae and in clinical cases recorded by the area health clinic. The method provides a highly specific and sensitive tool for monitoring the dynamics of V. cholerae in the environment. The RNA blot hybridization protocol can also be applied to detection of other gram-negative bacteria for taxon-specific enumeration. VL - 75 SN - 0099-2240, 1098-5336 UR - http://aem.asm.org/content/75/17/5439 CP - 17 M3 - 10.1128/AEM.02007-08 ER - TY - JOUR T1 - Robust Estimation of Albedo for Illumination-Invariant Matching and Shape Recovery JF - Pattern Analysis and Machine Intelligence, IEEE Transactions on Y1 - 2009 A1 - Biswas,S. A1 - Aggarwal,G. A1 - Chellapa, Rama KW - albedo estimation;error statistics;face recognition;illumination-invariant matching;nonstationary stochastic filtering;robust estimation;shape recovery;shape-from-shading approach;error statistics;face recognition;filtering theory;image matching;Algorithm KW - Automated;Photometry;Reproducibility of Results;Sensitivity and Specificity; KW - Computer-Assisted;Imaging KW - Three-Dimensional;Lighting;Pattern Recognition AB - We present a nonstationary stochastic filtering framework for the task of albedo estimation from a single image. There are several approaches in the literature for albedo estimation, but few include the errors in estimates of surface normals and light source direction to improve the albedo estimate. The proposed approach effectively utilizes the error statistics of surface normals and illumination direction for robust estimation of albedo, for images illuminated by single and multiple light sources. The albedo estimate obtained is subsequently used to generate albedo-free normalized images for recovering the shape of an object. Traditional shape-from-shading (SFS) approaches often assume constant/piecewise constant albedo and known light source direction to recover the underlying shape. Using the estimated albedo, the general problem of estimating the shape of an object with varying albedo map and unknown illumination source is reduced to one that can be handled by traditional SFS approaches. Experimental results are provided to show the effectiveness of the approach and its application to illumination-invariant matching and shape recovery. The estimated albedo maps are compared with the ground truth. The maps are used as illumination-invariant signatures for the task of face recognition across illumination variations. The recognition results obtained compare well with the current state-of-the-art approaches. Impressive shape recovery results are obtained using images downloaded from the Web with little control over imaging conditions. The recovered shapes are also used to synthesize novel views under novel illumination conditions. VL - 31 SN - 0162-8828 CP - 5 M3 - 10.1109/TPAMI.2008.135 ER - TY - JOUR T1 - The ruby intermediate language JF - SIGPLAN Not. Y1 - 2009 A1 - Furr,Michael A1 - An,Jong-hoon (David) A1 - Foster, Jeffrey S. A1 - Hicks, Michael W. KW - intermediate language KW - profile guided anlaysis KW - ril KW - ruby AB - Ruby is a popular, dynamic scripting language that aims to "feel natural to programmers" and give users the "freedom to choose" among many different ways of doing the same thing. While this arguably makes programming in Ruby easier, it makes it hard to build analysis and transformation tools that operate on Ruby source code. In this paper, we present the Ruby Intermediate Language (RIL), a Ruby front-end and intermediate representation that addresses these. RIL includes an extensible GLR parser for Ruby, and an automatic translation into an easy-to-analyze intermediate form. This translation eliminates redundant language constructs, unravels the often subtle ordering among side effecting operations, and makes implicit interpreter operations explicit. We also describe several additional useful features of RIL, such as a dynamic instrumentation library for profiling source code and a dataflow analysis engine. We demonstrate the usefulness of RIL by presenting a static and dynamic analysis to eliminate null pointer errors in Ruby programs. We hope that RIL's features will enable others to more easily build analysis tools for Ruby, and that our design will inspire the of similar frameworks for other dynamic languages. VL - 44 SN - 0362-1340 UR - http://doi.acm.org/10.1145/1837513.1640148 CP - 12 M3 - 10.1145/1837513.1640148 ER - TY - JOUR T1 - Scheduling on Unrelated Machines under Tree-Like Precedence Constraints JF - Algorithmica Y1 - 2009 A1 - Anil Kumar,V. A1 - Marathe,Madhav A1 - Parthasarathy,Srinivasan A1 - Srinivasan, Aravind AB - We present polylogarithmic approximations for the R | prec | C max and R | prec |∑ j w j C j problems, when the precedence constraints are “treelike”—i.e., when the undirected graph underlying the precedences is a forest. These are the first non-trivial generalizations of the job shop scheduling problem to scheduling with precedence constraints that are not just chains. These are also the first non-trivial results for the weighted completion time objective on unrelated machines with precedence constraints of any kind . We obtain improved bounds for the weighted completion time and flow time for the case of chains with restricted assignment—this generalizes the job shop problem to these objective functions. We use the same lower bound of “congestion + dilation”, as in other job shop scheduling approaches (e.g. Shmoys, Stein and Wein, SIAM J. Comput. 23, 617–632, 1994 ). The first step in our algorithm for the R | prec | C max problem with treelike precedences involves using the algorithm of Lenstra, Shmoys and Tardos to obtain a processor assignment with the congestion + dilation value within a constant factor of the optimal. We then show how to generalize the random-delays technique of Leighton, Maggs and Rao to the case of trees. For the special case of chains, we show a dependent rounding technique which leads to a bicriteria approximation algorithm for minimizing the flow time, a notoriously hard objective function. VL - 55 SN - 0178-4617 UR - http://dx.doi.org/10.1007/s00453-007-9004-y CP - 1 ER - TY - JOUR T1 - Sensory grammars for sensor networks JF - Journal of Ambient Intelligence and Smart Environments Y1 - 2009 A1 - Aloimonos, J. VL - 1 CP - 1 ER - TY - JOUR T1 - Serogroup, Virulence, and Genetic Traits of Vibrio Parahaemolyticus in the Estuarine Ecosystem of Bangladesh JF - Applied and Environmental MicrobiologyAppl. Environ. Microbiol. Y1 - 2009 A1 - Alam,Munirul A1 - Chowdhury,Wasimul B. A1 - Bhuiyan,N. A. A1 - Islam,Atiqul A1 - Hasan,Nur A. A1 - Nair,G. Balakrish A1 - Watanabe,H. A1 - Siddique,A. K. A1 - Huq,Anwar A1 - Sack,R. Bradley A1 - Akhter,M. Z. A1 - Grim,Christopher J. A1 - Kam,K.-M. A1 - Luey,C. K. Y. A1 - Endtz,Hubert P. A1 - Cravioto,Alejandro A1 - Rita R Colwell AB - Forty-two strains of Vibrio parahaemolyticus were isolated from Bay of Bengal estuaries and, with two clinical strains, analyzed for virulence, phenotypic, and molecular traits. Serological analysis indicated O8, O3, O1, and K21 to be the major O and K serogroups, respectively, and O8:K21, O1:KUT, and O3:KUT to be predominant. The K antigen(s) was untypeable, and pandemic serogroup O3:K6 was not detected. The presence of genes toxR and tlh were confirmed by PCR in all but two strains, which also lacked toxR. A total of 18 (41%) strains possessed the virulence gene encoding thermostable direct hemolysin (TDH), and one had the TDH-related hemolysin (trh) gene, but not tdh. Ten (23%) strains exhibited Kanagawa phenomenon that surrogates virulence, of which six, including the two clinical strains, possessed tdh. Of the 18 tdh-positive strains, 17 (94%), including the two clinical strains, had the seromarker O8:K21, one was O9:KUT, and the single trh-positive strain was O1:KUT. None had the group-specific or ORF8 pandemic marker gene. DNA fingerprinting employing pulsed-field gel electrophoresis (PFGE) of SfiI-digested DNA and cluster analysis showed divergence among the strains. Dendrograms constructed using PFGE (SfiI) images from a soft database, including those of pandemic and nonpandemic strains of diverse geographic origin, however, showed that local strains formed a cluster, i.e., “clonal cluster,” as did pandemic strains of diverse origin. The demonstrated prevalence of tdh-positive and diarrheagenic serogroup O8:K21 strains in coastal villages of Bangladesh indicates a significant human health risk for inhabitants. VL - 75 SN - 0099-2240, 1098-5336 UR - http://aem.asm.org/content/75/19/6268 CP - 19 M3 - 10.1128/AEM.00266-09 ER - TY - JOUR T1 - Space-time tradeoffs for approximate nearest neighbor searching JF - Journal of the ACM (JACM) Y1 - 2009 A1 - Arya,Sunil A1 - Malamatos,Theocharis A1 - Mount, Dave KW - nearest neighbor searching KW - space-time tradeoffs AB - Nearest neighbor searching is the problem of preprocessing a set of n point points in d-dimensional space so that, given any query point q, it is possible to report the closest point to q rapidly. In approximate nearest neighbor searching, a parameter ϵ > 0 is given, and a multiplicative error of (1 + ϵ) is allowed. We assume that the dimension d is a constant and treat n and ϵ as asymptotic quantities. Numerous solutions have been proposed, ranging from low-space solutions having space O(n) and query time O(log n + 1/ϵd−1) to high-space solutions having space roughly O((n log n)/ϵd) and query time O(log (n/ϵ)). We show that there is a single approach to this fundamental problem, which both improves upon existing results and spans the spectrum of space-time tradeoffs. Given a tradeoff parameter γ, where 2 ≤ γ ≤ 1/ϵ, we show that there exists a data structure of space O(nγd−1 log(1/ϵ)) that can answer queries in time O(log(nγ) + 1/(ϵγ)(d−1)/2. When γ = 2, this yields a data structure of space O(n log (1/ϵ)) that can answer queries in time O(log n + 1/ϵ(d−1)/2). When γ = 1/ϵ, it provides a data structure of space O((n/ϵd−1)log(1/ϵ)) that can answer queries in time O(log(n/ϵ)). Our results are based on a data structure called a (t,ϵ)-AVD, which is a hierarchical quadtree-based subdivision of space into cells. Each cell stores up to t representative points of the set, such that for any query point q in the cell at least one of these points is an approximate nearest neighbor of q. We provide new algorithms for constructing AVDs and tools for analyzing their total space requirements. We also establish lower bounds on the space complexity of AVDs, and show that, up to a factor of O(log (1/ϵ)), our space bounds are asymptotically tight in the two extremes, γ = 2 and γ = 1/ϵ. VL - 57 SN - 0004-5411 UR - http://doi.acm.org/10.1145/1613676.1613677 CP - 1 M3 - 10.1145/1613676.1613677 ER - TY - CONF T1 - Static type inference for Ruby T2 - Proceedings of the 2009 ACM symposium on Applied Computing Y1 - 2009 A1 - Furr,Michael A1 - An,Jong-hoon (David) A1 - Foster, Jeffrey S. A1 - Hicks, Michael W. KW - Contracts KW - dynamic typing KW - ruby KW - Type inference AB - Many general-purpose, object-oriented scripting languages are dynamically typed, which provides flexibility but leaves the programmer without the benefits of static typing, including early error detection and the documentation provided by type annotations. This paper describes Diamondback Ruby (DRuby), a tool that blends Ruby's dynamic type system with a static typing discipline. DRuby provides a type language that is rich enough to precisely type Ruby code we have encountered, without unneeded complexity. When possible, DRuby infers static types to discover type errors in Ruby programs. When necessary, the programmer can provide DRuby with annotations that assign static types to dynamic code. These annotations are checked at run time, isolating type errors to unverified code. We applied DRuby to a suite of benchmarks and found several bugs that would cause run-time type errors. DRuby also reported a number of warnings that reveal questionable programming practices in the benchmarks. We believe that DRuby takes a major step toward bringing the benefits of combined static and dynamic typing to Ruby and other object-oriented languages. JA - Proceedings of the 2009 ACM symposium on Applied Computing T3 - SAC '09 PB - ACM CY - New York, NY, USA SN - 978-1-60558-166-8 UR - http://doi.acm.org/10.1145/1529282.1529700 M3 - 10.1145/1529282.1529700 ER - TY - JOUR T1 - Surface reconstruction from gradient fields via gradient transformations JF - International Journal of Computer Vision Y1 - 2009 A1 - Agrawal,A. A1 - Raskar, R. A1 - Chellapa, Rama ER - TY - PAT T1 - System and Method for Spatio-Temporal-Context Aware Interaction of Users ... Y1 - 2009 A1 - Agrawala, Ashok K. A1 - Varshney, Amitabh A1 - Almazan,Christian B. ED - University of Maryland AB - A multifunctional interaction system which is capable of spatio-temporal context localization of users and of communication of audio/video streams to an entity of interest defined by the user, includes a communication domain supporting a predefined localization service, a server associated with the communication domain, client devices, and a dynamically changing context database which is customized in accord with the dynamics of interaction sessions of client devices with the server. The client communicates with the system to either request services therefrom or to send a message to the entity of interest. The system is provided with a panic alert mechanism which, upon actuation, transmits an audio/video data stream along with the client location tag, time stamp, and client ID, to a police precinct for prompt action. VL - 12/267,921 UR - http://www.google.com/patents?id=nZbGAAAAEBAJ ER - TY - CONF T1 - Tests to the left of me, types to the right: how not to get stuck in the middle of a ruby execution T2 - Proceedings for the 1st workshop on Script to Program Evolution Y1 - 2009 A1 - Furr,Michael A1 - An,Jong-hoon (David) A1 - Foster, Jeffrey S. A1 - Hicks, Michael W. AB - Ruby is a popular dynamic scripting language that permits terse, expressive code, but provides no static checks to detect errors before running the program. To address this, we have developed Diamond-back Ruby (DRuby), a tool that blends the benefits of static and dynamic typing. This paper briefly describes the main features of DRuby, which we will present in a tool demonstration. The presentation will concentrate on the development of a small, statically typed Ruby program, illustrating how DRuby might be used in practice. The audience will learn about some of the practical design decisions that went into DRuby, and how to use it to develop a type-safe Ruby program. JA - Proceedings for the 1st workshop on Script to Program Evolution T3 - STOP '09 PB - ACM CY - New York, NY, USA SN - 978-1-60558-543-7 UR - http://doi.acm.org/10.1145/1570506.1570508 M3 - 10.1145/1570506.1570508 ER - TY - CONF T1 - Translating HTNs to PDDL: A small amount of domain knowledge can go a long way Y1 - 2009 A1 - Alford,R. A1 - Kuter,U. A1 - Nau, Dana S. AB - We show how to translate HTN domain descrip- tions (if they satisfy certain restrictions) into PDDL so that they can be used by classical planners. We provide correctness results for our translation al- gorithm, and show that it runs in linear time and space. We also show that even small and incom- plete amounts of HTN knowledge, when translated into PDDL using our algorithm, can greatly im- prove a classical planner’s performance. In ex- periments on several thousand randomly gener- ated problems in three different planning domains, such knowledge speeded up the well-known Fast- Forward planner by several orders of magnitude, and enabled it to solve much larger problems than it could otherwise solve. UR - https://www.aaai.org/ocs/index.php/IJCAI/IJCAI-09/paper/download/573/853 ER - TY - CONF T1 - Validating Automotive Control Software Using Instrumentation-Based Verification T2 - Automated Software Engineering, International Conference on Y1 - 2009 A1 - Ray,Arnab A1 - Morschhaeuser,Iris A1 - Ackermann,Chris A1 - Cleaveland, Rance A1 - Shelton,Charles A1 - Martin,Chris AB - This paper discusses the results of an application of a formally based verification technique, called Instrumentation-Based Verification (IBV), to a production automotive lighting controller. The goal of the study is to assess, from both a tools as well as a methodological perspective, the performance of IBV in an industrial setting. The insights obtained as a result of the project include a refinement of a previously developed architecture for requirements specifications; observations about changes to model-based design workflows; insights into the role of requirements during development; and the capability of automated verification to detect inconsistencies among requirements as well as between requirements and design models. JA - Automated Software Engineering, International Conference on PB - IEEE Computer Society CY - Los Alamitos, CA, USA M3 - http://doi.ieeecomputersociety.org/10.1109/ASE.2009.98 ER - TY - JOUR T1 - Visual overviews for discovering key papers and influences across research fronts JF - Journal of the American Society for Information Science and Technology Y1 - 2009 A1 - Aris,Aleks A1 - Shneiderman, Ben A1 - Qazvinian,Vahed A1 - Radev,Dragomir AB - Gaining a rapid overview of an emerging scientific topic, sometimes called research fronts, is an increasingly common task due to the growing amount of interdisciplinary collaboration. Visual overviews that show temporal patterns of paper publication and citation links among papers can help researchers and analysts to see the rate of growth of topics, identify key papers, and understand influences across subdisciplines. This article applies a novel network-visualization tool based on meaningful layouts of nodes to present research fronts and show citation links that indicate influences across research fronts. To demonstrate the value of two-dimensional layouts with multiple regions and user control of link visibility, we conducted a design-oriented, preliminary case study with 6 domain experts over a 4-month period. The main benefits were being able (a) to easily identify key papers and see the increasing number of papers within a research front, and (b) to quickly see the strength and direction of influence across related research fronts. VL - 60 SN - 1532-2890 UR - http://onlinelibrary.wiley.com/doi/10.1002/asi.21160/abstract CP - 11 M3 - 10.1002/asi.21160 ER - TY - CONF T1 - Voronoi++: ADynamic Page Segmentation approach based on Voronoi and Docstrum features T2 - International Conference on Document Analysis and Recognition (ICDAR '09) Y1 - 2009 A1 - Agrawal,Mudit A1 - David Doermann AB - This paper presents a dynamic approach to document page segmentation. Current page segmentation algorithms lack the ability to dynamically adapt local variations in the size, orientation and distance of components within a page. Our approach builds upon one of the best algorithms, Kise et. al. work based on Area Voronoi Diagrams, which adapts globally to page content to determine algorithm parameters. In our approach, local thresholds are determined dynamically based on parabolic relations between components, and Docstrum based angular and neighborhood features are integrated to improve accuracy. Zone-based evaluation was performed on four sets of printed and handwritten documents in English and Arabic scripts and an increase of 33% in accuracy is reported. JA - International Conference on Document Analysis and Recognition (ICDAR '09) ER - TY - JOUR T1 - What puts the “meta” in metacognition? JF - Behavioral and Brain Sciences Y1 - 2009 A1 - Anderson,M. L A1 - Perlis, Don VL - 32 CP - 02 ER - TY - JOUR T1 - Accountable internet protocol (aip) JF - SIGCOMM Comput. Commun. Rev. Y1 - 2008 A1 - Andersen,David G. A1 - Balakrishnan,Hari A1 - Feamster, Nick A1 - Koponen,Teemu A1 - Moon,Daekyeong A1 - Shenker,Scott KW - accountability KW - address KW - internet architecture KW - scalability KW - Security AB - This paper presents AIP (Accountable Internet Protocol), a network architecture that provides accountability as a first-order property. AIP uses a hierarchy of self-certifying addresses, in which each component is derived from the public key of the corresponding entity. We discuss how AIP enables simple solutions to source spoofing, denial-of-service, route hijacking, and route forgery. We also discuss how AIP's design meets the challenges of scaling, key management, and traffic engineering. VL - 38 SN - 0146-4833 UR - http://doi.acm.org/10.1145/1402946.1402997 CP - 4 M3 - 10.1145/1402946.1402997 ER - TY - JOUR T1 - Active logic semantics for a single agent in a static world JF - Artificial Intelligence Y1 - 2008 A1 - Anderson,Michael L. A1 - Gomaa,Walid A1 - Grant,John A1 - Perlis, Don KW - Active logic KW - Autonomous agents KW - Brittleness KW - Logic KW - Nonmonotonic logic KW - Paraconsistent logic KW - semantics KW - Soundness KW - TIME AB - For some time we have been developing, and have had significant practical success with, a time-sensitive, contradiction-tolerant logical reasoning engine called the active logic machine (ALMA). The current paper details a semantics for a general version of the underlying logical formalism, active logic. Central to active logic are special rules controlling the inheritance of beliefs in general (and of beliefs about the current time in particular), very tight controls on what can be derived from direct contradictions (P&¬P), and mechanisms allowing an agent to represent and reason about its own beliefs and past reasoning. Furthermore, inspired by the notion that until an agent notices that a set of beliefs is contradictory, that set seems consistent (and the agent therefore reasons with it as if it were consistent), we introduce an "apperception function" that represents an agent's limited awareness of its own beliefs, and serves to modify inconsistent belief sets so as to yield consistent sets. Using these ideas, we introduce a new definition of logical consequence in the context of active logic, as well as a new definition of soundness such that, when reasoning with consistent premises, all classically sound rules remain sound in our new sense. However, not everything that is classically sound remains sound in our sense, for by classical definitions, all rules with contradictory premises are vacuously sound, whereas in active logic not everything follows from a contradiction. VL - 172 SN - 0004-3702 UR - http://www.sciencedirect.com/science/article/pii/S0004370207001993 CP - 8-9 M3 - 16/j.artint.2007.11.005 ER - TY - JOUR T1 - Activity representation using 3D shape models JF - J. Image Video Process. Y1 - 2008 A1 - Abdelkader,Mohamed F. A1 - Roy-Chowdhury,Amit K. A1 - Chellapa, Rama A1 - Akdemir,Umut AB - We present a method for characterizing human activities using 3D deformable shape models. The motion trajectories of points extracted from objects involved in the activity are used to build models for each activity, and these models are used for classification and detection of unusual activities. The deformable models are learnt using the factorization theorem for nonrigid 3D models. We present a theory for characterizing the degree of deformation in the 3D models from a sequence of tracked observations. This degree, termed as deformation index (DI), is used as an input to the 3D model estimation process. We study the special case of ground plane activities in detail because of its importance in video surveillance applications. We present results of our activity modeling approach using videos of both high-resolution single individual activities and ground plane surveillance activities. VL - 2008 SN - 1687-5176 UR - http://dx.doi.org/10.1155/2008/347050 M3 - 10.1155/2008/347050 ER - TY - CONF T1 - Answering what-if deployment and configuration questions with wise T2 - Proceedings of the ACM SIGCOMM 2008 conference on Data communication Y1 - 2008 A1 - Tariq,Mukarram A1 - Zeitoun,Amgad A1 - Valancius,Vytautas A1 - Feamster, Nick A1 - Ammar,Mostafa KW - content distribution networks KW - performance modeling KW - what-if scenario evaluation AB - Designers of content distribution networks often need to determine how changes to infrastructure deployment and configuration affect service response times when they deploy a new data center, change ISP peering, or change the mapping of clients to servers. Today, the designers use coarse, back-of-the-envelope calculations, or costly field deployments; they need better ways to evaluate the effects of such hypothetical "what-if" questions before the actual deployments. This paper presents What-If Scenario Evaluator (WISE), a tool that predicts the effects of possible configuration and deployment changes in content distribution networks. WISE makes three contributions: (1) an algorithm that uses traces from existing deployments to learn causality among factors that affect service response-time distributions; (2) an algorithm that uses the learned causal structure to estimate a dataset that is representative of the hypothetical scenario that a designer may wish to evaluate, and uses these datasets to predict future response-time distributions; (3) a scenario specification language that allows a network designer to easily express hypothetical deployment scenarios without being cognizant of the dependencies between variables that affect service response times. Our evaluation, both in a controlled setting and in a real-world field deployment at a large, global CDN, shows that WISE can quickly and accurately predict service response-time distributions for many practical What-If scenarios. JA - Proceedings of the ACM SIGCOMM 2008 conference on Data communication T3 - SIGCOMM '08 PB - ACM CY - New York, NY, USA SN - 978-1-60558-175-0 UR - http://doi.acm.org/10.1145/1402958.1402971 M3 - 10.1145/1402958.1402971 ER - TY - JOUR T1 - Biofilms in water, its role and impact in human disease transmission JF - Current Opinion in Biotechnology Y1 - 2008 A1 - Huq,Anwar A1 - Whitehouse,Chris A. A1 - Grim,Christopher J. A1 - Alam,Munirul A1 - Rita R Colwell AB - Understanding the mechanism of biofilm formation is the first step in determining its function and, thereby, its impact and role in the environment. Extensive studies accomplished during the past few years have elucidated the genetics and biochemistry of biofilm formation. Cell-to-cell communication, that is, quorum sensing, is a key factor in the initiation of biofilm. Occurrence of viable but nonculturable bacteria, including Vibrio cholerae in biofilms has been reported and most likely such cells were overlooked previously because appropriate methods of detection were not employed. For this reason discovery and investigation of this important bacterial ecological niche in the environment were impeded. VL - 19 SN - 0958-1669 UR - http://www.sciencedirect.com/science/article/pii/S0958166908000505 CP - 3 M3 - 10.1016/j.copbio.2008.04.005 ER - TY - JOUR T1 - A Constrained Probabilistic Petri Net Framework for Human Activity Detection in Video JF - Multimedia, IEEE Transactions on Y1 - 2008 A1 - Albanese, M. A1 - Chellapa, Rama A1 - Moscato, V. A1 - Picariello, A. A1 - V.S. Subrahmanian A1 - Turaga,P. A1 - Udrea,O. KW - activity KW - dataset;automated KW - detection;human KW - interactions;security KW - net;human KW - nets;image KW - Petri KW - probabilistic KW - processing;multiagent KW - processing;video KW - representation;low-level KW - representation;video KW - signal KW - Surveillance KW - surveillance; KW - systems;constrained KW - systems;surveillance KW - tarmac KW - TSA KW - videos;Petri AB - Recognition of human activities in restricted settings such as airports, parking lots and banks is of significant interest in security and automated surveillance systems. In such settings, data is usually in the form of surveillance videos with wide variation in quality and granularity. Interpretation and identification of human activities requires an activity model that a) is rich enough to handle complex multi-agent interactions, b) is robust to uncertainty in low-level processing and c) can handle ambiguities in the unfolding of activities. We present a computational framework for human activity representation based on Petri nets. We propose an extension-Probabilistic Petri Nets (PPN)-and show how this model is well suited to address each of the above requirements in a wide variety of settings. We then focus on answering two types of questions: (i) what are the minimal sub-videos in which a given activity is identified with a probability above a certain threshold and (ii) for a given video, which activity from a given set occurred with the highest probability? We provide the PPN-MPS algorithm for the first problem, as well as two different algorithms (naive PPN-MPA and PPN-MPA) to solve the second. Our experimental results on a dataset consisting of bank surveillance videos and an unconstrained TSA tarmac surveillance dataset show that our algorithms are both fast and provide high quality results. VL - 10 SN - 1520-9210 CP - 6 M3 - 10.1109/TMM.2008.2001369 ER - TY - JOUR T1 - Covariability of Vibrio Cholerae Microdiversity and Environmental Parameters JF - Applied and Environmental MicrobiologyAppl. Environ. Microbiol. Y1 - 2008 A1 - Zo,Young-Gun A1 - Chokesajjawatee,Nipa A1 - Arakawa,Eiji A1 - Watanabe,Haruo A1 - Huq,Anwar A1 - Rita R Colwell AB - Fine-scale diversity of natural bacterial assemblages has been attributed to neutral radiation because correspondence between bacterial phylogenetic signals in the natural environment and environmental parameters had not been detected. Evidence that such correspondence occurs is provided for Vibrio cholerae, establishing a critical role for environmental parameters in bacterial diversity. VL - 74 SN - 0099-2240, 1098-5336 UR - http://aem.asm.org/content/74/9/2915 CP - 9 M3 - 10.1128/AEM.02139-07 ER - TY - RPRT T1 - CrossTalk: The Journal of Defense Software Engineering. Volume 21, Number 10, October 2008 Y1 - 2008 A1 - Basili, Victor R. A1 - Dangle,K. A1 - Esker,L. A1 - Marotta,F. A1 - Rus,I. A1 - Brosgol,B. M A1 - Jamin,S. A1 - Arthur,J. D A1 - Ravichandar,R. A1 - Wisnosky,D. E PB - DTIC Document ER - TY - CHAP T1 - Delegating Capabilities in Predicate Encryption Systems T2 - Automata, Languages and Programming Y1 - 2008 A1 - Elaine Shi A1 - Waters,Brent ED - Aceto,Luca ED - Damgård,Ivan ED - Goldberg,Leslie ED - Halldórsson,Magnús ED - Ingólfsdóttir,Anna ED - Walukiewicz,Igor KW - Computer science AB - In predicate encryption systems, given a capability, one can evaluate one or more predicates on the plaintext encrypted, while all other information about the plaintext remains hidden. We consider the role of delegation in such predicate encryption systems. Suppose Alice has a capability, and she wishes to delegate to Bob a more restrictive capability allowing the decryption of a subset of the information Alice can learn about the plaintext encrypted. We formally define delegation in predicate encryption systems, propose a new security definition for delegation, and give an efficient construction supporting conjunctive queries. The security of our construction can be reduced to the general 3-party Bilinear Diffie-Hellman assumption, and the Bilinear Decisional Diffie-Hellman assumption in composite order bilinear groups. JA - Automata, Languages and Programming T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 5126 SN - 978-3-540-70582-6 UR - http://www.springerlink.com/content/w320422h15050004/abstract/ ER - TY - JOUR T1 - Development of a multi-piece multi-gate mold for manufacturing a flapping wing drive-mechanism JF - Transactions of North American Manufacturing Research Institution of SME Y1 - 2008 A1 - Ananthanarayanan,A. A1 - Bejgerowski,W. A1 - Mueller,D. A1 - Gupta,S.K. AB - Successful realization a flapping wing microair vehicle (MAV) requires development of a light weight drive-mechanism that can convert the continuous rotary motion to oscillatory flapping motion. Molded compliant drive-mechanisms are an attractive design option because of manufacturing scalability and reduction in the number of parts. The unique characteristics of this mechanism require development of a complex multi-piece multi-gate mold design. This paper describes a systematic approach for determining the part shape and size, optimizing the mold pieces, and placing the gates on the multi-piece mold. The novel aspects of this work include (1) selecting non-critical shape features to optimize the mold design and (2) the use of sacrificial structural elements to reduce the impact of the weld lines on the structural performance. The mold developed using our approach was utilized to realize a working flapping wing MAV. VL - 36 UR - http://web.mit.edu/arvinda/www/NAMRI_2008_Draft.pdf ER - TY - CONF T1 - Document Zone Classification Using Partial Least Squares and Hybrid Classifiers T2 - ICPR 2008. 19th International Conference on Pattern Recognition, 2008. Y1 - 2008 A1 - Abd-Almageed, Wael A1 - Agrawal,Mudit A1 - Seo,W. A1 - David Doermann AB - This paper introduces a novel document-zone classification algorithm. Low level image features are first extracted from document zones and partial least squares is used on pairs of classes to compute discriminating pairwise features. Rather than using the popular one-against-all and one-against-one voting schemes, we introduce a novel hybrid method which combines the benefits of the two schemes. The algorithm is applied on the University of Washington dataset and 97.3% classification accuracy is obtained. JA - ICPR 2008. 19th International Conference on Pattern Recognition, 2008. ER - TY - CONF T1 - Enhancements in robust feature matching T2 - Electrical Engineering/Electronics, Computer, Telecommunications and Information Technology, 2008. ECTI-CON 2008. 5th International Conference on Y1 - 2008 A1 - Ratanasanya,S. A1 - Mount, Dave A1 - Netanyahu,N. S A1 - Achalakul,T. KW - branch-and-bound algorithm KW - distance measure KW - Image Enhancement KW - Image matching KW - robust feature matching KW - tree searching AB - We present in this paper a number of new enhancements to a branch-and-bound algorithm given by Mount, Netanyahu, and Le Moigne [8] for feature matching. We introduce a new distance measure, which is more robust to the presence of outliers than the previously used measure, as well as a new variant of the search algorithm and a new search strategy. We also present experimental results, which show that these enhancements offer significant tangible improvements in performance. JA - Electrical Engineering/Electronics, Computer, Telecommunications and Information Technology, 2008. ECTI-CON 2008. 5th International Conference on VL - 1 M3 - 10.1109/ECTICON.2008.4600481 ER - TY - JOUR T1 - Exurbia from the bottom-up: Confronting empirical challenges to characterizing a complex system JF - Geoforum Y1 - 2008 A1 - Brown,Daniel G. A1 - Robinson,Derek T. A1 - An,Li A1 - Nassauer,Joan I. A1 - Zellner,Moira A1 - Rand, William A1 - Riolo,Rick A1 - Page,Scott E. A1 - Low,Bobbi A1 - Wang,Zhifang KW - Ecological effects KW - Land-cover change KW - Land-use change KW - spatial modeling KW - Urban sprawl AB - We describe empirical results from a multi-disciplinary project that support modeling complex processes of land-use and land-cover change in exurban parts of Southeastern Michigan. Based on two different conceptual models, one describing the evolution of urban form as a consequence of residential preferences and the other describing land-cover changes in an exurban township as a consequence of residential preferences, local policies, and a diversity of development types, we describe a variety of empirical data collected to support the mechanisms that we encoded in computational agent-based models. We used multiple methods, including social surveys, remote sensing, and statistical analysis of spatial data, to collect data that could be used to validate the structure of our models, calibrate their specific parameters, and evaluate their output. The data were used to investigate this system in the context of several themes from complexity science, including have (a) macro-level patterns; (b) autonomous decision making entities (i.e., agents); (c) heterogeneity among those entities; (d) social and spatial interactions that operate across multiple scales and (e) nonlinear feedback mechanisms. The results point to the importance of collecting data on agents and their interactions when producing agent-based models, the general validity of our conceptual models, and some changes that we needed to make to these models following data analysis. The calibrated models have been and are being used to evaluate landscape dynamics and the effects of various policy interventions on urban land-cover patterns. VL - 39 SN - 0016-7185 UR - http://www.sciencedirect.com/science/article/pii/S0016718507000371 CP - 2 M3 - 10.1016/j.geoforum.2007.02.010 ER - TY - CHAP T1 - Flow Analysis, Linearity, and PTIME T2 - Static Analysis Y1 - 2008 A1 - David Van Horn A1 - Mairson, Harry G. ED - Alpuente, María ED - Vidal, Germán KW - Logics and Meanings of Programs KW - Mathematical Logic and Formal Languages KW - Programming Languages, Compilers, Interpreters KW - Programming Techniques KW - software engineering AB - Flow analysis is a ubiquitous and much-studied component of compiler technology—and its variations abound. Amongst the most well known is Shivers’ 0CFA; however, the best known algorithm for 0CFA requires time cubic in the size of the analyzed program and is unlikely to be improved. Consequently, several analyses have been designed to approximate 0CFA by trading precision for faster computation. Henglein’s simple closure analysis, for example, forfeits the notion of directionality in flows and enjoys an “almost linear” time algorithm. But in making trade-offs between precision and complexity, what has been given up and what has been gained? Where do these analyses differ and where do they coincide? We identify a core language—the linear λ-calculus—where 0CFA, simple closure analysis, and many other known approximations or restrictions to 0CFA are rendered identical. Moreover, for this core language, analysis corresponds with (instrumented) evaluation. Because analysis faithfully captures evaluation, and because the linear λ-calculus is complete for ptime, we derive ptime-completeness results for all of these analyses. JA - Static Analysis T3 - Lecture Notes in Computer Science PB - Springer Berlin Heidelberg SN - 978-3-540-69163-1, 978-3-540-69166-2 UR - http://link.springer.com/chapter/10.1007/978-3-540-69166-2_17 ER - TY - CONF T1 - Flowers or a robot army?: encouraging awareness & activity with personal, mobile displays T2 - Proceedings of the 10th international conference on Ubiquitous computing Y1 - 2008 A1 - Consolvo,Sunny A1 - Klasnja,Predrag A1 - McDonald,David W. A1 - Avrahami,Daniel A1 - Jon Froehlich A1 - LeGrand,Louis A1 - Libby,Ryan A1 - Mosher,Keith A1 - Landay,James A. KW - ambient display KW - awareness KW - calm technology KW - field experiment KW - fitness KW - glanceable display KW - mobile phone KW - personal mobile display KW - persuasive technology KW - physical activity AB - Personal, mobile displays, such as those on mobile phones, are ubiquitous, yet for the most part, underutilized. We present results from a field experiment that investigated the effectiveness of these displays as a means for improving awareness of daily life (in our case, self-monitoring of physical activity). Twenty-eight participants in three experimental conditions used our UbiFit system for a period of three months in their day-to-day lives over the winter holiday season. Our results show, for example, that participants who had an awareness display were able to maintain their physical activity level (even during the holidays), while the level of physical activity for participants who did not have an awareness display dropped significantly. We discuss our results and their general implications for the use of everyday mobile devices as awareness displays. JA - Proceedings of the 10th international conference on Ubiquitous computing T3 - UbiComp '08 PB - ACM CY - New York, NY, USA SN - 978-1-60558-136-1 UR - http://doi.acm.org/10.1145/1409635.1409644 M3 - 10.1145/1409635.1409644 ER - TY - JOUR T1 - Genome-Wide Analysis of Repetitive Elements in Papaya JF - Tropical Plant Biology Y1 - 2008 A1 - Nagarajan,Niranjan A1 - Navajas-Pérez,Rafael A1 - Pop, Mihai A1 - Alam,Maqsudul A1 - Ming,Ray A1 - Paterson,Andrew A1 - Salzberg,Steven AB - Papaya ( Carica papaya L.) is an important fruit crop cultivated in tropical and subtropical regions worldwide. A first draft of its genome sequence has been recently released. Together with Arabidopsis , rice, poplar, grapevine and other genomes in the pipeline, it represents a good opportunity to gain insight into the organization of plant genomes. Here we report a detailed analysis of repetitive elements in the papaya genome, including transposable elements (TEs), tandemly-arrayed sequences, and high copy number genes. These repetitive sequences account for ∼56% of the papaya genome with TEs being the most abundant at 52%, tandem repeats at 1.3% and high copy number genes at 3%. Most common types of TEs are represented in the papaya genome with retrotransposons being the dominant class, accounting for 40% of the genome. The most prevalent retrotransposons are Ty3-gypsy (27.8%) and Ty1-copia (5.5%). Among the tandem repeats, microsatellites are the most abundant in number, but represent only 0.19% of the genome. Minisatellites and satellites are less abundant, but represent 0.68% and 0.43% of the genome, respectively, due to greater repeat length. Despite an overall smaller gene repertoire in papaya than many other angiosperms, a significant fraction of genes (>2%) are present in large gene families with copy number greater than 20. This repeat database clarified a major part of the papaya genome organization and partly explained the lower gene repertoire in papaya than in Arabidopsis . VL - 1 SN - 1935-9756 UR - http://dx.doi.org/10.1007/s12042-008-9015-0 CP - 3 ER - TY - CONF T1 - Hci for community and international development T2 - SIGCHI EA '08 Y1 - 2008 A1 - Thomas, John A1 - Dearden, Andy A1 - Dray, Susan A1 - Light, Ann A1 - Best, Michael A1 - Arkin, Nuray A1 - Maunder, Andrew A1 - Kam, Mathew A1 - Marshini Chetty A1 - Sambasivan, Nithya A1 - Buckhalter, Celeste A1 - Krishnan, Gaurishankar KW - community design KW - ict4d KW - information and communication technology KW - international development KW - participatory design KW - ucd4id KW - User centered design AB - This workshop explores the challenges in applying, extending and inventing appropriate methods and contributions of Human Computer Interaction (HCI) to International economic and community Development. We address interaction design for parts of the world that are often marginalized by the Global North as well as people in the Global North who are themselves similarly marginalized by poverty or other barriers. We hope to extend the boundaries of the field of Human Computer Interaction by spurring a discussion on how existing methods and practices can be adapted and modified, and how new practices can be developed, to deal with the unique challenges posed by these contexts. JA - SIGCHI EA '08 T3 - CHI EA '08 PB - ACM SN - 978-1-60558-012-8 UR - http://doi.acm.org/10.1145/1358628.1358954 ER - TY - CONF T1 - Human detection using iterative feature selection and logistic principal component analysis T2 - Robotics and Automation, 2008. ICRA 2008. IEEE International Conference on Y1 - 2008 A1 - Abd-Almageed, Wael A1 - Davis, Larry S. KW - algorithm;logistic KW - analysis;edge KW - analysis;probability; KW - applications;principal KW - belongness KW - component KW - DETECTION KW - detection;feature KW - detection;iterative KW - detection;principal KW - extraction;filtering KW - feature KW - filtering;human KW - MAP KW - methods;object KW - PCA;object KW - probability;edge KW - selection KW - theory;iterative AB - We present a fast feature selection algorithm suitable for object detection applications where the image being tested must be scanned repeatedly to detected the object of interest at different locations and scales. The algorithm iteratively estimates the belongness probability of image pixels to foreground of the image. To prove the validity of the algorithm, we apply it to a human detection problem. The edge map is filtered using a feature selection algorithm. The filtered edge map is then projected onto an eigen space of human shapes to determine if the image contains a human. Since the edge maps are binary in nature, Logistic Principal Component Analysis is used to obtain the eigen human shape space. Experimental results illustrate the accuracy of the human detector. JA - Robotics and Automation, 2008. ICRA 2008. IEEE International Conference on M3 - 10.1109/ROBOT.2008.4543444 ER - TY - JOUR T1 - Learning To Predict Bad Behavior JF - NIPS 2007 Workshop on Machine Learning in Adversarial Environments for Computer Security Y1 - 2008 A1 - Ahmed Syed,N. A1 - Feamster, Nick A1 - Gray,A. ER - TY - CONF T1 - A Logic Framework for Sports Video Summarization Using Text-Based Semantic Annotation T2 - Semantic Media Adaptation and Personalization, 2008. SMAP '08. Third International Workshop on Y1 - 2008 A1 - Refaey,M.A. A1 - Abd-Almageed, Wael A1 - Davis, Larry S. KW - (mathematics);video KW - analysis;trees KW - annotation;Internet;broadcasting;sport;text KW - AUTOMATIC KW - detection;logic KW - engine;parse KW - event KW - PROCESSING KW - processing; KW - semantic KW - signal KW - summarization;text KW - trees;sports KW - video KW - Webcasting;text-based AB - Detection of semantic events in sports videos is an essential step towards video summarization. A large volume of research has been conducted for automatic semantic event detection and summarization of sports videos. In this paper we present a novel sports video summarization framework using a combination of text, video and logic analysis. Parse trees are used to analyze structured and free-style text webcasting of sports games and extract the game¿s semantic events, such as goals and penalties in soccer games. Semantic events are then hierarchically arranged before being passed to a logic processing engine. The logic engine receives the summary preferences from the user and subsequently parses the event hierarchy to generate the game¿s summary according to the user¿s preferences. The proposed framework was applied to both soccer and basketball videos. We achieved an average accuracy of 98.6% and 100% on soccer and basketball videos, respectively. JA - Semantic Media Adaptation and Personalization, 2008. SMAP '08. Third International Workshop on M3 - 10.1109/SMAP.2008.25 ER - TY - CONF T1 - Measuring 1st order stretchwith a single filter T2 - IEEE International Conference on Acoustics, Speech and Signal Processing, 2008. ICASSP 2008 Y1 - 2008 A1 - Bitsakos,K. A1 - Domke, J. A1 - Fermüller, Cornelia A1 - Aloimonos, J. KW - Cepstral analysis KW - Educational institutions KW - filter KW - filtering theory KW - Fourier transforms KW - Frequency domain analysis KW - Frequency estimation KW - Gabor filters KW - Image analysis KW - IMAGE PROCESSING KW - linear stretch measurement KW - local signal transformation measurement KW - Nonlinear filters KW - Phase estimation KW - Signal analysis KW - Speech processing AB - We analytically develop a filter that is able to measure the linear stretch of the transformation around a point, and present results of applying it to real signals. We show that this method is a real-time alternative solution for measuring local signal transformations. Experimentally, this method can accurately measure stretch, however, it is sensitive to shift. JA - IEEE International Conference on Acoustics, Speech and Signal Processing, 2008. ICASSP 2008 PB - IEEE SN - 978-1-4244-1483-3 M3 - 10.1109/ICASSP.2008.4517758 ER - TY - RPRT T1 - Model Based Design Verification: A Monitor Based Approach Y1 - 2008 A1 - Ackermann,Chris A1 - Ray,Arnab A1 - Cleaveland, Rance A1 - Heit,Jürgen A1 - Martin,Christopher A1 - Shelton,Charles AB - This paper assesses the utility of an automated functional verification methodology in the design of a body electronics application. The use of design models as detailed specifications for software is gaining steady acceptance in the automotive industry because of the advantages it offers in terms of rapid system prototyping and automatic code generation. This paper argues that such modeling effort can also be used to provide support for design verification, so that errors may be pinpointed before they find their way into code, when they become much harder and more expensive to isolate, diagnose and repair. PB - SAE International CY - Warrendale, PA VL - 2008-01-0741 UR - http://papers.sae.org/2008-01-0741 ER - TY - CONF T1 - Multi-biometric cohort analysis for biometric fusion T2 - Acoustics, Speech and Signal Processing, 2008. ICASSP 2008. IEEE International Conference on Y1 - 2008 A1 - Aggarwal,G. A1 - Ratha,N. K A1 - Bolle, R.M. A1 - Chellapa, Rama KW - (access KW - analysis;biometrics KW - biometric KW - biometrics;fingerprint KW - biometrics;multi-biometric KW - cohort KW - control);face KW - data; KW - decisions;face KW - fusion;biometric KW - identification;security KW - MATCHING KW - of KW - recognition;fingerprint AB - Biometric matching decisions have traditionally been made based solely on a score that represents the similarity of the query biometric to the enrolled biometric(s) of the claimed identity. Fusion schemes have been proposed to benefit from the availability of multiple biometric samples (e.g., multiple samples of the same fingerprint) or multiple different biometrics (e.g., face and fingerprint). These commonly adopted fusion approaches rarely make use of the large number of non-matching biometric samples available in the database in the form of other enrolled identities or training data. In this paper, we study the impact of combining this information with the existing fusion methodologies in a cohort analysis framework. Experimental results are provided to show the usefulness of such a cohort-based fusion of face and fingerprint biometrics. JA - Acoustics, Speech and Signal Processing, 2008. ICASSP 2008. IEEE International Conference on M3 - 10.1109/ICASSP.2008.4518837 ER - TY - JOUR T1 - New records of phytoplankton for Bangladesh. 2. Cryptophyceae and Synurophyceae JF - Bangladesh Journal of Botany Y1 - 2008 A1 - Khondker,Moniruzzaman A1 - Bhuiyan,Rauf Ahmed A1 - Yeasmin,Jenat A1 - Alam,Munirul A1 - Sack,R. Bradley A1 - Huq,Anwar A1 - Rita R Colwell AB - This study presents two species of Rhodomonas, four species of Chroomonas, six species of Cryptomonas and Cryptochrysis minor, Cyanomonas coeruleus, Chrysodidymus synuroideus and Mallomonas akrokomos. These species have been reported from some ponds of Mathbaria in Pirojpur and Bakerganj of Barisal district in Bangladesh. VL - 36 SN - 0253-5416 UR - http://www.banglajol.info/bd/index.php/BJB/article/viewArticle/1549 CP - 1 M3 - 10.3329/bjb.v36i1.1549 ER - TY - JOUR T1 - New records of phytoplankton for Bangladesh. 5. Euglena, Euglenocapsa JF - Bangladesh Journal of Plant Taxonomy Y1 - 2008 A1 - Khondker,Moniruzzaman A1 - Bhuiyan,Rauf Ahmed A1 - Yeasmin,Jenat A1 - Alam,Munirul A1 - Sack,R. Bradley A1 - Huq,Anwar A1 - Rita R Colwell AB - This study presents 20 taxa of the genus Euglena and one species of the rare euglenoid genus Euglenocapsa. All these taxa are reported for the first time from some pond ecosystems of Mathbaria in Pirojpur and Bakerganj of Barisal districts of Bangladesh. VL - 15 SN - 1028-2092 UR - http://www.banglajol.info/index.php/BJPT/article/viewArticle/910 CP - 1 M3 - 10.3329/bjpt.v15i1.910 ER - TY - JOUR T1 - New records of phytoplankton for Bangladesh. 7. Phacus spp. JF - Bangladesh Journal of Botany Y1 - 2008 A1 - Khondker,Moniruzzaman A1 - Bhuiyan,Rauf Ahmed A1 - Yeasmin,Jenat A1 - Alam,Munirul A1 - Sack,R. Bradley A1 - Huq,Anwar A1 - Rita R Colwell AB - Thirteen species of Phacus hitherto not reported from Bangladesh have been described and illustrated. Freshwater ponds at southern districts of Pirojpur and Barisal revealed these presence of the species. VL - 37 SN - 0253-5416 UR - http://www.banglajol.info/bd/index.php/BJB/article/viewArticle/1564 CP - 1 M3 - 10.3329/bjb.v37i1.1564 ER - TY - JOUR T1 - New records of phytoplankton for Bangladesh. 8. Trachelomonas Ehr. (Euglenophyceae) JF - Bangladesh Journal of Botany Y1 - 2008 A1 - Khondker,Moniruzzaman A1 - Bhuiyan,Rauf Ahmed A1 - Yeasmin,Jenat A1 - Alam,Munirul A1 - Sack,R. Bradley A1 - Huq,Anwar A1 - Rita R Colwell AB - Investigation of pelagic plankton communities from some freshwater ponds of Pirojpur and Barisal districts revealed the presence of 17 species under the genus Trachelomonas Ehr. for the first time in Bangladesh. VL - 37 SN - 0253-5416 UR - http://www.banglajol.info/bd/index.php/BJB/article/viewArticle/1719 CP - 2 M3 - 10.3329/bjb.v37i2.1719 ER - TY - RPRT T1 - A Node Aggregation Strategy to Reduce Complexity of Network Visualization using Semantic Substrates Y1 - 2008 A1 - Aris,A. A1 - Shneiderman, Ben AB - Semantic substrates are spatial templates for networks, wherenodes are grouped into regions and laid out within each region according to one or more node attributes. Analysts’ ability to design their own substrates leads to a different approach than other more automatic approaches to layout nodes (force-directed, circular, etc.). While the semantic substrate approach provides more interpretable node locations, sometimes a set of nodes is compressed into a small space on the display, leading to node overlap. In this paper, we significantly improve this situation by introducing the node aggregation mechanism in the context of semantic substrates. We illustrate this functionality in a document citation network and provide pros and cons of the approach. We conclude with guidelines and future directions for this research. Throughout the paper, examples are illustrated with NVSS 3.0, the network visualization tool developed to explore the semantic substrate idea. PB - Human-Computer Interaction Lab, University of Maryland ER - TY - CONF T1 - A Non-generative Approach for Face Recognition Across Aging T2 - Biometrics: Theory, Applications and Systems, 2008. BTAS 2008. 2nd IEEE International Conference on Y1 - 2008 A1 - Biswas,S. A1 - Aggarwal,G. A1 - Ramanathan,N. A1 - Chellapa, Rama KW - appearance;nongenerative KW - approach;face KW - Face KW - image KW - matching; KW - recognition;facial KW - recognition;image KW - synthesis;face AB - Human faces undergo a lot of change in appearance as they age. Though facial aging has been studied for decades, it is only recently that attempts have been made to address the problem from a computational point of view. Most of these early efforts follow a simulation approach in which matching is performed by synthesizing face images at the target age. Given the innumerable different ways in which a face can potentially age, the synthesized aged image may not be similar to the actual aged image. In this paper, we bypass the synthesis step and directly analyze the drifts of facial features with aging from a purely matching perspective. Our analysis is based on the observation that facial appearance changes in a coherent manner as people age. We provide measures to capture this coherency in feature drifts. Illustrations and experimental results show the efficacy of such an approach for matching faces across age progression. JA - Biometrics: Theory, Applications and Systems, 2008. BTAS 2008. 2nd IEEE International Conference on M3 - 10.1109/BTAS.2008.4699331 ER - TY - JOUR T1 - Occurrence and Expression of Luminescence in Vibrio Cholerae JF - Applied and Environmental MicrobiologyAppl. Environ. Microbiol. Y1 - 2008 A1 - Grim,Christopher J. A1 - Taviani,Elisa A1 - Alam,Munirul A1 - Huq,Anwar A1 - Sack,R. Bradley A1 - Rita R Colwell AB - Several species of the genus Vibrio, including Vibrio cholerae, are bioluminescent or contain bioluminescent strains. Previous studies have reported that only 10% of V. cholerae strains are luminescent. Analysis of 224 isolates of non-O1/non-O139 V. cholerae collected from Chesapeake Bay, MD, revealed that 52% (116/224) were luminescent when an improved assay method was employed and 58% (130/224) of isolates harbored the luxA gene. In contrast, 334 non-O1/non-O139 V. cholerae strains isolated from two rural provinces in Bangladesh yielded only 21 (6.3%) luminescent and 35 (10.5%) luxA+ isolates. An additional 270 clinical and environmental isolates of V. cholerae serogroups O1 and O139 were tested, and none were luminescent or harbored luxA. These results indicate that bioluminescence may be a trait specific for non-O1/non-O139 V. cholerae strains that frequently occur in certain environments. Luminescence expression patterns of V. cholerae were also investigated, and isolates could be grouped based on expression level. Several strains with defective expression of the lux operon, including natural K variants, were identified. VL - 74 SN - 0099-2240, 1098-5336 UR - http://aem.asm.org/content/74/3/708 CP - 3 M3 - 10.1128/AEM.01537-07 ER - TY - CONF T1 - An ontology based approach for activity recognition from video T2 - Proceedings of the 16th ACM international conference on Multimedia Y1 - 2008 A1 - Akdemir,Umut A1 - Turaga,Pavan A1 - Chellapa, Rama KW - activity ontologies KW - visual surveillance AB - Representation and recognition of human activities is an important problem for video surveillance and security applications. Considering the wide variety of settings in which surveillance systems are being deployed, it is necessary to create a common knowledge-base or ontology of human activities. Most current attempts at ontology design in computer vision for human activities have been empirical in nature. In this paper, we present a more systematic approach to address the problem of designing ontologies for visual activity recognition. We draw on general ontology design principles and adapt them to the specific domain of human activity ontologies. Then, we discuss qualitative evaluation principles and provide several examples from existing ontologies and how they can be improved upon. Finally, we demonstrate quantitatively in terms of recognition performance, the efficacy and validity of our approach for bank and airport tarmac surveillance domains. JA - Proceedings of the 16th ACM international conference on Multimedia T3 - MM '08 PB - ACM CY - New York, NY, USA SN - 978-1-60558-303-7 UR - http://doi.acm.org/10.1145/1459359.1459466 M3 - 10.1145/1459359.1459466 ER - TY - CHAP T1 - Optimal Cryptographic Hardness of Learning Monotone Functions T2 - Automata, Languages and Programming Y1 - 2008 A1 - Dana Dachman-Soled A1 - Lee, Homin K. A1 - Malkin, Tal A1 - Servedio, Rocco A. A1 - Wan, Andrew A1 - Wee, Hoeteck ED - Aceto, Luca ED - Damgård, Ivan ED - Goldberg, Leslie Ann ED - Halldórsson, Magnús M. ED - Ingólfsdóttir, Anna ED - Walukiewicz, Igor KW - Data structures KW - Data Structures, Cryptology and Information Theory KW - Discrete Mathematics in Computer Science KW - Numeric Computing KW - Software Engineering/Programming and Operating Systems KW - Theory of computation AB - A wide range of positive and negative results have been established for learning different classes of Boolean functions from uniformly distributed random examples. However, polynomial-time algorithms have thus far been obtained almost exclusively for various classes of monotone functions, while the computational hardness results obtained to date have all been for various classes of general (nonmonotone) functions. Motivated by this disparity between known positive results (for monotone functions) and negative results (for nonmonotone functions), we establish strong computational limitations on the efficient learnability of various classes of monotone functions. We give several such hardness results which are provably almost optimal since they nearly match known positive results. Some of our results show cryptographic hardness of learning polynomial-size monotone circuits to accuracy only slightly greater than 1/2+1/n‾‾√1/2 + 1/\sqrt{n} ; this accuracy bound is close to optimal by known positive results (Blum et al., FOCS ’98). Other results show that under a plausible cryptographic hardness assumption, a class of constant-depth, sub-polynomial-size circuits computing monotone functions is hard to learn; this result is close to optimal in terms of the circuit size parameter by known positive results as well (Servedio, Information and Computation ’04). Our main tool is a complexity-theoretic approach to hardness amplification via noise sensitivity of monotone functions that was pioneered by O’Donnell (JCSS ’04). JA - Automata, Languages and Programming T3 - Lecture Notes in Computer Science PB - Springer Berlin Heidelberg SN - 978-3-540-70574-1, 978-3-540-70575-8 UR - http://link.springer.com/chapter/10.1007/978-3-540-70575-8_4 ER - TY - JOUR T1 - Pose and Illumination Issues in Face-and Gait-Based Identification JF - Advances in Biometrics Y1 - 2008 A1 - Chellapa, Rama A1 - Aggarwal,G. AB - Although significant work has been done in the field of face- and gait- based recognition, the performance of the state-of-the-art recognition algorithms is not good enough to be effective in operational systems. Most algorithms do reasonably well for controlled images but are susceptible to changes in illumination conditions and pose. This has shifted the focus of research to more challenging tasks of obtaining better performance for uncontrolled realistic scenarios. In this chapter, we discuss several recent advances made to achieve this goal. ER - TY - CHAP T1 - The Randomized Coloring Procedure with Symmetry-Breaking T2 - Automata, Languages and ProgrammingAutomata, Languages and Programming Y1 - 2008 A1 - Pemmaraju,Sriram A1 - Srinivasan, Aravind ED - Aceto,Luca ED - Damgård,Ivan ED - Goldberg,Leslie ED - Halldórsson,Magnús ED - Ingólfsdóttir,Anna ED - Walukiewicz,Igor AB - A basic randomized coloring procedure has been used in probabilistic proofs to obtain remarkably strong results on graph coloring. These results include the asymptotic version of the List Coloring Conjecture due to Kahn, the extensions of Brooks’ Theorem to sparse graphs due to Kim and Johansson, and Luby’s fast parallel and distributed algorithms for graph coloring. The most challenging aspect of a typical probabilistic proof is showing adequate concentration bounds for key random variables. In this paper, we present a simple symmetry-breaking augmentation to the randomized coloring procedure that works well in conjunction with Azuma’s Martingale Inequality to easily yield the requisite concentration bounds. We use this approach to obtain a number of results in two areas: frugal coloring and weighted equitable coloring . A β-frugal coloring of a graph G is a proper vertex-coloring of G in which no color appears more than β times in any neighborhood. Let G = ( V , E ) be a vertex-weighted graph with weight function w : V →[0, 1] and let W = ∑ v ∈ V w ( v ). A weighted equitable coloring of G is a proper k -coloring such that the total weight of every color class is “large”, i.e., “not much smaller” than W / k ; this notion is useful in obtaining tail bounds for sums of dependent random variables. JA - Automata, Languages and ProgrammingAutomata, Languages and Programming T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 5125 SN - 978-3-540-70574-1 UR - http://dx.doi.org/10.1007/978-3-540-70575-8_26 ER - TY - CONF T1 - Readability of scanned books in digital libraries T2 - Proceeding of the twenty-sixth annual SIGCHI conference on Human factors in computing systems Y1 - 2008 A1 - Quinn,A.J. A1 - Hu,C. A1 - Arisaka,T. A1 - Rose,A. A1 - Bederson, Benjamin B. JA - Proceeding of the twenty-sixth annual SIGCHI conference on Human factors in computing systems ER - TY - CONF T1 - Re-Targetable OCR with Intelligent Character Segmentation T2 - DAS '08: Proceedings of the 2008 The Eighth IAPRInternational Workshop on Document Analysis Systems Y1 - 2008 A1 - Agrawal,Mudit A1 - David Doermann AB - We have developed a font-model based intelligent character segmentation and recognition system. Using characteristics of structurally similar TrueType fonts, our system automatically builds a model to be used for the segmentation and recognition of the new script, independent of glyph composition. The key is a reliance on known font attributes. In our system three feature extraction methods are used to demonstrate the importance of appropriate features for classification. The methods are tested on both Latin (English) and non-Latin (Khmer) scripts. Results show that the character-level recognition accuracy exceeds 92% for Khmer and 96% for English on degraded documents. This work is a step toward the recognition of scripts of low-density languages which typically do not warrant the development of commercial OCR, yet often have complete TrueType font descriptions. JA - DAS '08: Proceedings of the 2008 The Eighth IAPRInternational Workshop on Document Analysis Systems ER - TY - CONF T1 - The role of metacognition in robust AI systems T2 - AAAI-08 Workshop on Metareasoning,(Chicago, IL) Y1 - 2008 A1 - Schmill,M. D A1 - Oates,T. A1 - Anderson,M. A1 - Fults,S. A1 - Josyula,D. A1 - Perlis, Don A1 - Wilson,S. JA - AAAI-08 Workshop on Metareasoning,(Chicago, IL) ER - TY - CONF T1 - Scalable network distance browsing in spatial databases T2 - Proceedings of the 2008 ACM SIGMOD international conference on Management of data Y1 - 2008 A1 - Samet, Hanan A1 - Sankaranarayanan,Jagan A1 - Alborzi,Houman KW - decoupling KW - nearest neighbor KW - scalability KW - shortest path quadtree KW - spatial networks AB - An algorithm is presented for finding the k nearest neighbors in a spatial network in a best-first manner using network distance. The algorithm is based on precomputing the shortest paths between all possible vertices in the network and then making use of an encoding that takes advantage of the fact that the shortest paths from vertex u to all of the remaining vertices can be decomposed into subsets based on the first edges on the shortest paths to them from u. Thus, in the worst case, the amount of work depends on the number of objects that are examined and the number of links on the shortest paths to them from q, rather than depending on the number of vertices in the network. The amount of storage required to keep track of the subsets is reduced by taking advantage of their spatial coherence which is captured by the aid of a shortest path quadtree. In particular, experiments on a number of large road networks as well as a theoretical analysis have shown that the storage has been reduced from O(N3) to O(N1.5) (i.e., by an order of magnitude equal to the square root). The precomputation of the shortest paths along the network essentially decouples the process of computing shortest paths along the network from that of finding the neighbors, and thereby also decouples the domain S of the query objects and that of the objects from which the neighbors are drawn from the domain V of the vertices of the spatial network. This means that as long as the spatial network is unchanged, the algorithm and underlying representation of the shortest paths in the spatial network can be used with different sets of objects. JA - Proceedings of the 2008 ACM SIGMOD international conference on Management of data T3 - SIGMOD '08 PB - ACM CY - New York, NY, USA SN - 978-1-60558-102-6 UR - http://doi.acm.org/10.1145/1376616.1376623 M3 - 10.1145/1376616.1376623 ER - TY - JOUR T1 - Seasonal Cholera from Multiple Small Outbreaks, Rural Bangladesh JF - Emerging Infectious DiseasesEmerg Infect Dis Y1 - 2008 A1 - Stine,O. Colin A1 - Alam,Munirul A1 - Tang,Li A1 - Nair,G. Balakrish A1 - Siddique,A. Kasem A1 - Faruque,Shah M. A1 - Huq,Anwar A1 - Rita R Colwell A1 - Sack,R. Bradley A1 - Morris,J. Glenn AB - Clinical and environmental Vibrio cholerae organisms collected from February 2004 through April 2005 were systematically isolated from 2 rural Bangladeshi locales. Their genetic relatedness was evaluated at 5 loci that contained a variable number of tandem repeats (VNTR). The observed minimal overlap in VNTR patterns between the 2 communities was consistent with sequential, small outbreaks from local sources. VL - 14 SN - 1080-6040 CP - 5 M3 - 10.3201/eid1405.071116 ER - TY - JOUR T1 - A self-help guide for autonomous systems JF - AI Magazine Y1 - 2008 A1 - Anderson,M. L A1 - Fults,S. A1 - Josyula,D. P A1 - Oates,T. A1 - Perlis, Don A1 - Wilson,S. A1 - Wright,D. VL - 29 CP - 2 ER - TY - JOUR T1 - Space-time tradeoffs for proximity searching in doubling spaces JF - Algorithms-ESA 2008 Y1 - 2008 A1 - Arya,S. A1 - Mount, Dave A1 - Vigneron,A. A1 - Xia,J. AB - We consider approximate nearest neighbor searching in metric spaces of constant doubling dimension. More formally, we are given a set S of n points and an error bound ε> 0. The objective is to build a data structure so that given any query point q in the space, it is possible to efficiently determine a point of S whose distance from q is within a factor of (1 + ε) of the distance between q and its nearest neighbor in S. In this paper we obtain the following space-time tradeoffs. Given a parameter γ ∈ [2,1/ε], we show how to construct a data structure of space nO(dim)log(1) space that can answer queries in time O(log(n))+(1())O(dim) . This is the first result that offers space-time tradeoffs for approximate nearest neighbor queries in doubling spaces. At one extreme it nearly matches the best result currently known for doubling spaces, and at the other extreme it results in a data structure that can answer queries in time O(log(n/ε)), which matches the best query times in Euclidean space. Our approach involves a novel generalization of the AVD data structure from Euclidean space to doubling space. M3 - 10.1007/978-3-540-87744-8_10 ER - TY - CONF T1 - A Survey of the Virtual Environments-based Assembly Training Applications Y1 - 2008 A1 - Gupta,S.K. A1 - Anand,D. K. A1 - Brough,J. E. A1 - Kavetsky,R. A. A1 - Schwartz,M. A1 - Thakur,A. AB - The advent of virtual environments is presenting new ways of trainingtomorrow’s workforce. Virtual environments offer numerous benefits in training applications. First, virtual environments allow extensive user interactions in a very convenient and natural manner. This interaction is greatly beneficial for increasing the user’s retention of spatial information compared to text-based or video-based instructions that are non-interactive in nature. Second, virtual environments provide users with a 3D immersive experience. This feature helps users gain a better understanding of spatial relationships compared to 2D displays. Third, virtual environments support multi-media instructions. One can watch standard videos, view 3D animations, view text instructions, listen to audio instructions, and interact with 3D objects in the scene. This paper describes representative research and associated systems that use of virtual environments in assembly training applications. UR - http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.151.2892&rep=rep1&type=pdf ER - TY - CONF T1 - Synthesis of strategies from interaction traces Y1 - 2008 A1 - Au,Tsz-Chiu A1 - Kraus,Sarit A1 - Nau, Dana S. KW - agents KW - interaction KW - learning KW - multi-agent systems KW - prisoner's dilemma KW - repeated games AB - We describe how to take a set of interaction traces produced by different pairs of players in a two-player repeated game, and combine them into a composite strategy. We provide an algorithm that, in polynomial time, can generate the best such composite strategy. We describe how to incorporate the composite strategy into an existing agent, as an enhancement of the agent's original strategy. We provide experimental results using interaction traces from 126 agents (most of them written by students as class projects) for the Iterated Prisoner's Dilemma, Iterated Chicken Game, and Iterated Battle of the Sexes. We compared each agent with the enhanced version of that agent produced by our algorithm. The enhancements improved the agents' scores by about 5% in the IPD, 11% in the ICG, and 26% in the IBS, and improved their rank by about 12% in the IPD, 38% in the ICG, and 33% in the IBS. T3 - AAMAS '08 PB - International Foundation for Autonomous Agents and Multiagent Systems CY - Richland, SC SN - 978-0-9817381-1-6 UR - http://dl.acm.org/citation.cfm?id=1402298.1402343 ER - TY - JOUR T1 - Toward automatic facet analysis and need negotiation: Lessons from mediated search JF - ACM Transactions on Information Systems (TOIS) Y1 - 2008 A1 - Jimmy Lin A1 - Wu,Philip A1 - Abels,Eileen KW - interactive information retrieval KW - Reference interview AB - This work explores the hypothesis that interactions between a trained human search intermediary and an information seeker can inform the design of interactive IR systems. We discuss results from a controlled Wizard-of-Oz case study, set in the context of the TREC 2005 HARD track evaluation, in which a trained intermediary executed an integrated search and interaction strategy based on conceptual facet analysis and informed by need negotiation techniques common in reference interviews. Having a human “in the loop” yielded large improvements over fully automated systems as measured by standard ranked-retrieval metrics, demonstrating the value of mediated search. We present a detailed analysis of the intermediary's actions to gain a deeper understanding of what worked and why. One contribution is a taxonomy of clarification types informed both by empirical results and existing theories in library and information science. We discuss how these findings can guide the development of future systems. Overall, this work illustrates how studying human information-seeking processes can lead to better information retrieval applications. VL - 27 SN - 1046-8188 UR - http://doi.acm.org/10.1145/1416950.1416956 CP - 1 M3 - 10.1145/1416950.1416956 ER - TY - CONF T1 - Tradeoffs in Approximate Range Searching Made Simpler T2 - Computer Graphics and Image Processing, 2008. SIBGRAPI '08. XXI Brazilian Symposium on Y1 - 2008 A1 - Arya,S. A1 - Fonseca,G. A1 - Mount, Dave KW - approximate range searching KW - computational geometry KW - data structure KW - Data structures KW - query range AB - Range searching is a fundamental problem in computational geometry. The problem involves preprocessing a set of n points in R^d into a data structure, so that it is possible to determine the subset of points lying within a given query range. In approximate range searching, a parameter eps epsiv gt; 0 is given, and for a given query range R the points lying within distance eps diam(R) of the range's boundary may be counted or not. In this paper we present three results related to the issue of tradeoffs in approximate range searching. First, we introduce the range sketching problem. Next, we present a space-time tradeoff for smooth convex ranges, which generalize spherical ranges. Finally, we show how to modify the previous data structure to obtain a space-time tradeoff for simplex ranges. In contrast to existing results, which are based on relatively complex data structures, all three of our results are based on simple, practical data structures. JA - Computer Graphics and Image Processing, 2008. SIBGRAPI '08. XXI Brazilian Symposium on M3 - 10.1109/SIBGRAPI.2008.24 ER - TY - CONF T1 - Who killed the directed model? T2 - Computer Vision and Pattern Recognition, IEEE Computer Society Conference on Y1 - 2008 A1 - Domke, Justin A1 - Karapurkar, Alap A1 - Aloimonos, J. AB - Prior distributions are useful for robust low-level vision, and undirected models (e.g. Markov Random Fields) have become a central tool for this purpose. Though sometimes these priors can be specified by hand, this becomes difficult in large models, which has motivated learning these models from data. However, maximum likelihood learning of undirected models is extremely difficult- essentially all known methods require approximations and/or high computational cost. Conversely, directed models are essentially trivial to learn from data, but have not received much attention for low-level vision. We compare the two formalisms of directed and undirected models, and conclude that there is no a priori reason to believe one better represents low-level vision quantities. We formulate two simple directed priors, for natural images and stereo disparity, to empirically test if the undirected formalism is superior. We find in both cases that a simple directed model can achieve results similar to the best learnt undirected models with significant speedups in training time, suggesting that directed models are an attractive choice for tractable learning. JA - Computer Vision and Pattern Recognition, IEEE Computer Society Conference on PB - IEEE Computer Society CY - Los Alamitos, CA, USA SN - 978-1-4244-2242-5 M3 - http://doi.ieeecomputersociety.org/10.1109/CVPR.2008.4587817 ER - TY - JOUR T1 - Active semantic caching to optimize multidimensional data analysis in parallel and distributed environments JF - Parallel Computing Y1 - 2007 A1 - Andrade,Henrique A1 - Kurc,Tahsin A1 - Sussman, Alan A1 - Saltz,Joel KW - Active semantic caching KW - Parallel databases KW - Query optimization KW - Scientific data analysis AB - In this paper, we present a multi-query optimization framework based on the concept of active semantic caching. The framework permits the identification and transparent reuse of data and computation in the presence of multiple queries (or query batches) that specify user-defined operators and aggregations originating from scientific data-analysis applications. We show how query scheduling techniques, coupled with intelligent cache replacement policies, can further improve the performance of query processing by leveraging the active semantic caching operators. We also propose a methodology for functionally decomposing complex queries in terms of primitives so that multiple reuse sites are exposed to the query optimizer, to increase the amount of reuse. The optimization framework and the database system implemented with it are designed to be efficient irrespective of the underlying parallel and/or distributed machine configuration. We present experimental results highlighting the performance improvements obtained by our methods using real scientific data-analysis applications on multiple parallel and distributed processing configurations (e.g., single symmetric multiprocessor (SMP) machine, cluster of SMP nodes, and a Grid computing configuration). VL - 33 SN - 0167-8191 UR - http://www.sciencedirect.com/science/article/pii/S0167819107000506 CP - 7-8 M3 - 10.1016/j.parco.2007.03.001 ER - TY - JOUR T1 - Appearance Characterization of Linear Lambertian Objects, Generalized Photometric Stereo, and Illumination-Invariant Face Recognition JF - Pattern Analysis and Machine Intelligence, IEEE Transactions on Y1 - 2007 A1 - Zhou,S. K A1 - Aggarwal,G. A1 - Chellapa, Rama A1 - Jacobs, David W. KW - albedo field;appearance characterization;generalized photometric stereo algorithms;illumination-invariant face recognition;linear Lambertian objects;observation matrix factorization;face recognition;matrix decomposition;Algorithms;Artificial Intelligence; KW - Automated;Photogrammetry;Reproducibility of Results;Sensitivity and Specificity; KW - Computer-Assisted;Information Storage and Retrieval;Lighting;Linear Models;Pattern Recognition AB - Traditional photometric stereo algorithms employ a Lambertian reflectance model with a varying albedo field and involve the appearance of only one object. In this paper, we generalize photometric stereo algorithms to handle all appearances of all objects in a class, in particular the human face class, by making use of the linear Lambertian property. A linear Lambertian object is one which is linearly spanned by a set of basis objects and has a Lambertian surface. The linear property leads to a rank constraint and, consequently, a factorization of an observation matrix that consists of exemplar images of different objects (e.g., faces of different subjects) under different, unknown illuminations. Integrability and symmetry constraints are used to fully recover the subspace bases using a novel linearized algorithm that takes the varying albedo field into account. The effectiveness of the linear Lambertian property is further investigated by using it for the problem of illumination-invariant face recognition using just one image. Attached shadows are incorporated in the model by a careful treatment of the inherent nonlinearity in Lambert's law. This enables us to extend our algorithm to perform face recognition in the presence of multiple illumination sources. Experimental results using standard data sets are presented VL - 29 SN - 0162-8828 CP - 2 M3 - 10.1109/TPAMI.2007.25 ER - TY - CONF T1 - Application of MCL in a dialog agent T2 - Third Language and Technology Conference Y1 - 2007 A1 - Josyula,D. P A1 - Fults,S. A1 - Anderson,M. L A1 - Wilson,S. A1 - Perlis, Don JA - Third Language and Technology Conference ER - TY - CONF T1 - Bid based scheduler with backfilling for a multiprocessor system T2 - Proceedings of the ninth international conference on Electronic commerce Y1 - 2007 A1 - Yahav,I. A1 - Raschid, Louiqa A1 - Andrade,H. JA - Proceedings of the ninth international conference on Electronic commerce ER - TY - JOUR T1 - CARA: A Cultural-Reasoning Architecture JF - IEEE Intelligent Systems Y1 - 2007 A1 - V.S. Subrahmanian A1 - Albanese,Massimiliano A1 - Martinez,Mar?a Vanina A1 - Nau, Dana S. A1 - Reforgiato,Diego A1 - Simari,Gerardo I. A1 - Sliva,Amy A1 - Udrea,Octavian A1 - Wilkenfeld,Jonathan KW - cultural reasoning KW - opinion extraction KW - opponent modeling AB - The Cognitive Architecture for Reasoning about Adversaries supports methods to gather data about different cultural groups and learn the intensity of those groups' opinions on various topics. It also lets users build and extract models of those groups' behavior and continuously refine those models through shared multiperson learning experiences. Researchers have applied the architecture to develop cultural-reasoning applications for example, a game that teaches soldiers about cultural norms in an Afghan village. VL - 22 SN - 1541-1672 CP - 2 ER - TY - JOUR T1 - Combining outputs from multiple machine translation systems JF - Human Language Technologies 2007: The Conference of the North American Chapter of the Association for Computational Linguistics; Proceedings of the Main Conference Y1 - 2007 A1 - Rosti,A.V.I. A1 - Ayan,N.F. A1 - Xiang,B. A1 - Matsoukas,S. A1 - Schwartz,R. A1 - Dorr, Bonnie J AB - Currently there are several approaches tomachine translation (MT) based on differ- ent paradigms; e.g., phrasal, hierarchical and syntax-based. These three approaches yield similar translation accuracy despite using fairly different levels of linguistic knowledge. The availability of such a variety of systems has led to a growing interest toward finding better translations by combining outputs from multiple sys- tems. This paper describes three differ- ent approaches to MT system combina- tion. These combination methods oper- ate on sentence, phrase and word level exploiting information from N -best lists, system scores and target-to-source phrase alignments. The word-level combination provides the most robust gains but the best results on the development test sets (NIST MT05 and the newsgroup portion of GALE 2006 dry-run) were achieved by combining all three methods. ER - TY - CONF T1 - Data Clustering with a Relational Push-Pull Model T2 - Data Mining Workshops, 2007. ICDM Workshops 2007. Seventh IEEE International Conference on Y1 - 2007 A1 - Anthony,Adam A1 - desJardins, Marie AB - We present a new generative model for relational data in which relations between objects can have ei- ther a binding or a separating effect. For example, in a group of students separated into gender clusters, a "dating" relation would appear most frequently between the clusters, but a "roommate" relation would appear more often within clusters. In visualizing these rela- tions, one can imagine that the "dating" relation effec- tively pushes clusters apart, while the "roommate" re- lation pulls clusters into tighter formations. A unique aspect of the model is that an edge's existence is depen- dent on both the clusters to which the two connected objects belong and the features of the connected objects. We use simulated annealing to search for optimal val- ues of the unknown model parameters, where the ob- jective function is a Bayesian score derived from the generative model. Results describing the performance of the model are shown with artificial data as well as a subset of the Internet Movie Database. The results show that discovering a relation's tendency to either push or pull is critical to discovering a consistent clustering. JA - Data Mining Workshops, 2007. ICDM Workshops 2007. Seventh IEEE International Conference on PB - IEEE SN - 0-7695-3033-8, 978-0-7695-3019-2 UR - http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=4476666&tag=1 M3 - 10.1109/ICDMW.2007.61 ER - TY - CONF T1 - The defined cliffs variant in dynamic environments: a case study using the shaky ladder hyperplane-defined functions T2 - Proceedings of the 9th annual conference on Genetic and evolutionary computation Y1 - 2007 A1 - Alharbi,Abir A1 - Rand, William A1 - Riolo,Rick KW - building blocks KW - dynamic environments KW - Genetic algorithms KW - shaky ladder hyperplane-defined functions AB - The shaky ladder hyperplane-defined functions (sl-hdfs) are a test suite utilized for exploring the behavior of the genetic algorithm (GA) in dynamic environments. This test suite can generate arbitrary problems with similar levels of difficulty and it provides a platform for systematic controlled observations of the GA in dynamic environments. Previous work has found two factors that contribute to the GA's success on sl-hdfs: (1) short initial building blocks and (2) significantly changing the reward structure during fitness landscape changes. Therefore a test function that combines these two features should facilitate even better GA performance. This has led to the construction of a new sl-hdf variant, "Defined Cliffs," in which we combine short elementary building blocks with sharp transitions in the environment. We examine this variant with two different levels of dynamics, static and regularly changing, using four different metrics. The results show superior GA performance on the Defined Cliffs over all previous variants (Cliffs, Weight, and Smooth). Our observations and conclusions in this variant further the understanding of the GA in dynamic environments. JA - Proceedings of the 9th annual conference on Genetic and evolutionary computation T3 - GECCO '07 PB - ACM CY - New York, NY, USA SN - 978-1-59593-697-4 UR - http://doi.acm.org/10.1145/1276958.1277186 M3 - 10.1145/1276958.1277186 ER - TY - JOUR T1 - Designing Semantic Substrates for Visual Network Exploration JF - Information VisualizationInformation Visualization Y1 - 2007 A1 - Aris,Aleks A1 - Shneiderman, Ben KW - data exploration and analysis KW - Graphical user interfaces KW - Information Visualization KW - network visualization KW - semantic substrate design AB - A semantic substrate is a spatial template for a network, where nodes are grouped into regions and laid out within each region according to one or more node attributes. This paper shows how users can be given control in designing their own substrates and how this ability leads to a different approach to network data exploration. Users can create a semantic substrate, enter their data, get feedback from domain experts, edit the semantic substrate, and iteratively continue this procedure until the domain experts are satisfied with the insights they have gained. We illustrate this process in two case studies with domain experts working with legal precedents and food webs. Guidelines for designing substrates are provided, including how to locate, size, and align regions in a substrate, which attributes to choose for grouping nodes into regions, how to select placement methods and which attributes to set as parameters of the selected placement method. Throughout the paper, examples are illustrated with NVSS 2.0, the network visualization tool developed to explore the semantic substrate idea. VL - 6 SN - 1473-8716, 1473-8724 UR - http://ivi.sagepub.com/content/6/4/281 CP - 4 M3 - 10.1057/palgrave.ivs.9500162 ER - TY - CONF T1 - Detecting stochastically scheduled activities in video T2 - International Joint Conference on Artificial Intelligence Y1 - 2007 A1 - Albanese, M. A1 - Moscato, V. A1 - Picariello, A. A1 - V.S. Subrahmanian A1 - Udrea,O. AB - The ability to automatically detect activities invideo is of increasing importance in applications such as bank security, airport tarmac security, bag- gage area security and building site surveillance. We present a stochastic activity model composed of atomic actions which are directly observable through image understanding primitives. We focus on answering two types of questions: (i) what are the minimal sub-videos in which a given action is identified with probability above a certain thresh- old and (ii) for a given video, can we decide which activity from a given set most likely occurred? We provide the MPS algorithm for the first problem, as well as two different algorithms (naiveMPA and MPA) to solve the second. Our experimental re- sults on a dataset consisting of staged bank robbery videos (described in [Vu et al., 2003]) show that our algorithms are both fast and provide high qual- ity results when compared to human reviewers. JA - International Joint Conference on Artificial Intelligence ER - TY - JOUR T1 - Development of in-mold assembly process for realizing mesoscale revolute joints JF - Transactions of North American Manufacturing Research Institution of SME Y1 - 2007 A1 - Ananthanarayanan,A. A1 - Gupta,S.K. A1 - Bruck,H. A. A1 - Yu,Z. A1 - Rajurkar,K. P. AB - In-mold Assembly process at the mesoscalepresents several manufacturing challenges. Results reported in this paper demonstrate the technical feasibility of creating rigid body mesoscale revolute joints using In-Mold Assembly process. The following new results are reported in this paper. First, we describe a mold design with varying cavity shape to perform In-Mold Assembly. This mold design uses an accurate mold piece positioning method to avoid damage to delicate mesoscale parts during the cavity change step. Second, we describe a mold insert fabrication process for making mold inserts with the desired surface characteristics for mesoscale molding. Finally, we describe methods to limit the adhesion at the interfaces and hence create articulated revolute joint. Using the advances reported in this paper we have successfully molded a mesoscale revolute joint. To the best of our knowledge, this is the first demonstration of In-Mold Assembly process using a varying cavity shape mold to create a mesoscale revolute joint. VL - 35 UR - ftp://ftp.eng.umd.edu/:/home/glue/s/k/skgupta/pub/Publication/NAMRC07_Ananthanarayanan_draft.pdf ER - TY - CONF T1 - Discovering interesting usage patterns in text collections: integrating text mining with visualization T2 - Proceedings of the sixteenth ACM conference on Conference on information and knowledge management Y1 - 2007 A1 - Don,Anthony A1 - Zheleva,Elena A1 - Gregory,Machon A1 - Tarkan,Sureyya A1 - Auvil,Loretta A1 - Clement,Tanya A1 - Shneiderman, Ben A1 - Plaisant, Catherine KW - digital humanities KW - frequent closed itemsets KW - n-grams KW - text mining KW - user interface AB - This paper addresses the problem of making text mining results more comprehensible to humanities scholars, journalists, intelligence analysts, and other researchers, in order to support the analysis of text collections. Our system, FeatureLens1, visualizes a text collection at several levels of granularity and enables users to explore interesting text patterns. The current implementation focuses on frequent itemsets of n-grams, as they capture the repetition of exact or similar expressions in the collection. Users can find meaningful co-occurrences of text patterns by visualizing them within and across documents in the collection. This also permits users to identify the temporal evolution of usage such as increasing, decreasing or sudden appearance of text patterns. The interface could be used to explore other text features as well. Initial studies suggest that FeatureLens helped a literary scholar and 8 users generate new hypotheses and interesting insights using 2 text collections. JA - Proceedings of the sixteenth ACM conference on Conference on information and knowledge management T3 - CIKM '07 PB - ACM CY - New York, NY, USA SN - 978-1-59593-803-9 UR - http://doi.acm.org/10.1145/1321440.1321473 M3 - 10.1145/1321440.1321473 ER - TY - CHAP T1 - Distributed Ranked Search T2 - High Performance Computing – HiPC 2007High Performance Computing – HiPC 2007 Y1 - 2007 A1 - Gopalakrishnan,Vijay A1 - Morselli,Ruggero A1 - Bhattacharjee, Bobby A1 - Keleher,Pete A1 - Srinivasan, Aravind ED - Aluru,Srinivas ED - Parashar,Manish ED - Badrinath,Ramamurthy ED - Prasanna,Viktor AB - P2P deployments are a natural infrastructure for building distributed search networks. Proposed systems support locating and retrieving all results, but lack the information necessary to rank them. Users, however, are primarily interested in the most relevant results, not necessarily all possible results. Using random sampling, we extend a class of well-known information retrieval ranking algorithms such that they can be applied in this decentralized setting. We analyze the overhead of our approach, and quantify how our system scales with increasing number of documents, system size, document to node mapping (uniform versus non-uniform), and types of queries (rare versus popular terms). Our analysis and simulations show that a) these extensions are efficient, and scale with little overhead to large systems, and b) the accuracy of the results obtained using distributed ranking is comparable to that of a centralized implementation. JA - High Performance Computing – HiPC 2007High Performance Computing – HiPC 2007 T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 4873 SN - 978-3-540-77219-4 UR - http://dx.doi.org/10.1007/978-3-540-77220-0_6 ER - TY - JOUR T1 - Draft Genome of the Filarial Nematode Parasite Brugia Malayi JF - Science Y1 - 2007 A1 - Ghedin,Elodie A1 - Wang,Shiliang A1 - Spiro,David A1 - Caler,Elisabet A1 - Zhao,Qi A1 - Crabtree,Jonathan A1 - Allen,Jonathan E A1 - Delcher,Arthur L. A1 - Guiliano,David B A1 - Miranda-Saavedra,Diego A1 - Angiuoli,Samuel V A1 - Creasy,Todd A1 - Amedeo,Paolo A1 - Haas,Brian A1 - El‐Sayed, Najib M. A1 - Wortman,Jennifer R. A1 - Feldblyum,Tamara A1 - Tallon,Luke A1 - Schatz,Michael A1 - Shumway,Martin A1 - Koo,Hean A1 - Salzberg,Steven L. A1 - Schobel,Seth A1 - Pertea,Mihaela A1 - Pop, Mihai A1 - White,Owen A1 - Barton,Geoffrey J A1 - Carlow,Clotilde K. S A1 - Crawford,Michael J A1 - Daub,Jennifer A1 - Dimmic,Matthew W A1 - Estes,Chris F A1 - Foster,Jeremy M A1 - Ganatra,Mehul A1 - Gregory,William F A1 - Johnson,Nicholas M A1 - Jin,Jinming A1 - Komuniecki,Richard A1 - Korf,Ian A1 - Kumar,Sanjay A1 - Laney,Sandra A1 - Li,Ben-Wen A1 - Li,Wen A1 - Lindblom,Tim H A1 - Lustigman,Sara A1 - Ma,Dong A1 - Maina,Claude V A1 - Martin,David M. A A1 - McCarter,James P A1 - McReynolds,Larry A1 - Mitreva,Makedonka A1 - Nutman,Thomas B A1 - Parkinson,John A1 - Peregrín-Alvarez,José M A1 - Poole,Catherine A1 - Ren,Qinghu A1 - Saunders,Lori A1 - Sluder,Ann E A1 - Smith,Katherine A1 - Stanke,Mario A1 - Unnasch,Thomas R A1 - Ware,Jenna A1 - Wei,Aguan D A1 - Weil,Gary A1 - Williams,Deryck J A1 - Zhang,Yinhua A1 - Williams,Steven A A1 - Fraser-Liggett,Claire A1 - Slatko,Barton A1 - Blaxter,Mark L A1 - Scott,Alan L AB - Parasitic nematodes that cause elephantiasis and river blindness threaten hundreds of millions of people in the developing world. We have sequenced the ∼90 megabase (Mb) genome of the human filarial parasite Brugia malayi and predict ∼11,500 protein coding genes in 71 Mb of robustly assembled sequence. Comparative analysis with the free-living, model nematode Caenorhabditis elegans revealed that, despite these genes having maintained little conservation of local synteny during ∼350 million years of evolution, they largely remain in linkage on chromosomal units. More than 100 conserved operons were identified. Analysis of the predicted proteome provides evidence for adaptations of B. malayi to niches in its human and vector hosts and insights into the molecular basis of a mutualistic relationship with its Wolbachia endosymbiont. These findings offer a foundation for rational drug design. VL - 317 SN - 0036-8075, 1095-9203 UR - http://www.sciencemag.org/content/317/5845/1756 CP - 5845 M3 - 10.1126/science.1145406 ER - TY - CONF T1 - Efficient Indexing For Articulation Invariant Shape Matching And Retrieval T2 - Computer Vision and Pattern Recognition, 2007. CVPR '07. IEEE Conference on Y1 - 2007 A1 - Biswas,S. A1 - Aggarwal,G. A1 - Chellapa, Rama KW - alignment;image KW - articulation KW - geometric KW - invariant KW - matching;image KW - matching;indexing;invariant KW - relationships;shape-wise KW - retrieval;indexing; KW - retrieval;pairwise KW - SHAPE AB - Most shape matching methods are either fast but too simplistic to give the desired performance or promising as far as performance is concerned but computationally demanding. In this paper, we present a very simple and efficient approach that not only performs almost as good as many state-of-the-art techniques but also scales up to large databases. In the proposed approach, each shape is indexed based on a variety of simple and easily computable features which are invariant to articulations and rigid transformations. The features characterize pairwise geometric relationships between interest points on the shape, thereby providing robustness to the approach. Shapes are retrieved using an efficient scheme which does not involve costly operations like shape-wise alignment or establishing correspondences. Even for a moderate size database of 1000 shapes, the retrieval process is several times faster than most techniques with similar performance. Extensive experimental results are presented to illustrate the advantages of our approach as compared to the best in the field. JA - Computer Vision and Pattern Recognition, 2007. CVPR '07. IEEE Conference on M3 - 10.1109/CVPR.2007.383227 ER - TY - JOUR T1 - Evaluating a cross-cultural children’s online book community: Lessons learned for sociability, usability, and cultural exchange JF - Interacting with Computers Y1 - 2007 A1 - Komlodi,Anita A1 - Hou,Weimin A1 - Preece,Jenny A1 - Druin, Allison A1 - Golub,Evan A1 - Alburo,Jade A1 - Liao,Sabrina A1 - Elkiss,Aaron A1 - Resnik, Philip KW - children KW - Cross-cultural KW - Evaluation and design KW - International Children’s Digital Library KW - Online communities AB - The use of computers for human-to-human communication among adults has been studied for many years, but using computer technology to enable children from all over the world to talk to each other has rarely been discussed by researchers. The goal of our research is to fill this gap and explore the design and evaluation of children’s cross-language online communities via a case study of the International Children’s Digital Library Communities (ICDLCommunities). This project supports the development of communities for children (ages 7–11) that form around the International Digital Children’s Library (ICDL) book collection. In this community the children can learn about each others’ cultures and make friends even if they do not speak the same language. They can also read and create stories and ask and answer questions about these. From this evaluation study we learned that: (i) children are very interested in their counterparts in other countries and a remarkable amount of communication takes place even when they do not share a common language; (ii) representing their identity online in many different forms is particularly important to children when communicating in an online community; (iii) children enjoy drawing but representing stories in a sequence of diagrams is challenging and needs support; and (iv) asking and answering questions without language is possible using graphical templates. In this paper we present our findings and make recommendations for designing children’s cross-cultural online communities. VL - 19 SN - 0953-5438 UR - http://www.sciencedirect.com/science/article/pii/S0953543807000240 CP - 4 M3 - 10.1016/j.intcom.2007.03.001 ER - TY - JOUR T1 - Evolution of genes and genomes on the Drosophila phylogeny JF - Nature Y1 - 2007 A1 - Clark,Andrew G. A1 - Eisen,Michael B. A1 - Smith,Douglas R. A1 - Bergman,Casey M. A1 - Oliver,Brian A1 - Markow,Therese A. A1 - Kaufman,Thomas C. A1 - Kellis,Manolis A1 - Gelbart,William A1 - Iyer,Venky N. A1 - Pollard,Daniel A. A1 - Sackton,Timothy B. A1 - Larracuente,Amanda M. A1 - Singh,Nadia D. A1 - Abad,Jose P. A1 - Abt,Dawn N. A1 - Adryan,Boris A1 - Aguade,Montserrat A1 - Akashi,Hiroshi A1 - Anderson,Wyatt W. A1 - Aquadro,Charles F. A1 - Ardell,David H. A1 - Arguello,Roman A1 - Artieri,Carlo G. A1 - Barbash,Daniel A. A1 - Barker,Daniel A1 - Barsanti,Paolo A1 - Batterham,Phil A1 - Batzoglou,Serafim A1 - Begun,Dave A1 - Bhutkar,Arjun A1 - Blanco,Enrico A1 - Bosak,Stephanie A. A1 - Bradley,Robert K. A1 - Brand,Adrianne D. A1 - Brent,Michael R. A1 - Brooks,Angela N. A1 - Brown,Randall H. A1 - Butlin,Roger K. A1 - Caggese,Corrado A1 - Calvi,Brian R. A1 - Carvalho,A. Bernardo de A1 - Caspi,Anat A1 - Castrezana,Sergio A1 - Celniker,Susan E. A1 - Chang,Jean L. A1 - Chapple,Charles A1 - Chatterji,Sourav A1 - Chinwalla,Asif A1 - Civetta,Alberto A1 - Clifton,Sandra W. A1 - Comeron,Josep M. A1 - Costello,James C. A1 - Coyne,Jerry A. A1 - Daub,Jennifer A1 - David,Robert G. A1 - Delcher,Arthur L. A1 - Delehaunty,Kim A1 - Do,Chuong B. A1 - Ebling,Heather A1 - Edwards,Kevin A1 - Eickbush,Thomas A1 - Evans,Jay D. A1 - Filipski,Alan A1 - Findei|[szlig]|,Sven A1 - Freyhult,Eva A1 - Fulton,Lucinda A1 - Fulton,Robert A1 - Garcia,Ana C. L. A1 - Gardiner,Anastasia A1 - Garfield,David A. A1 - Garvin,Barry E. A1 - Gibson,Greg A1 - Gilbert,Don A1 - Gnerre,Sante A1 - Godfrey,Jennifer A1 - Good,Robert A1 - Gotea,Valer A1 - Gravely,Brenton A1 - Greenberg,Anthony J. A1 - Griffiths-Jones,Sam A1 - Gross,Samuel A1 - Guigo,Roderic A1 - Gustafson,Erik A. A1 - Haerty,Wilfried A1 - Hahn,Matthew W. A1 - Halligan,Daniel L. A1 - Halpern,Aaron L. A1 - Halter,Gillian M. A1 - Han,Mira V. A1 - Heger,Andreas A1 - Hillier,LaDeana A1 - Hinrichs,Angie S. A1 - Holmes,Ian A1 - Hoskins,Roger A. A1 - Hubisz,Melissa J. A1 - Hultmark,Dan A1 - Huntley,Melanie A. A1 - Jaffe,David B. A1 - Jagadeeshan,Santosh A1 - Jeck,William R. A1 - Johnson,Justin A1 - Jones,Corbin D. A1 - Jordan,William C. A1 - Karpen,Gary H. A1 - Kataoka,Eiko A1 - Keightley,Peter D. A1 - Kheradpour,Pouya A1 - Kirkness,Ewen F. A1 - Koerich,Leonardo B. A1 - Kristiansen,Karsten A1 - Kudrna,Dave A1 - Kulathinal,Rob J. A1 - Kumar,Sudhir A1 - Kwok,Roberta A1 - Lander,Eric A1 - Langley,Charles H. A1 - Lapoint,Richard A1 - Lazzaro,Brian P. A1 - Lee,So-Jeong A1 - Levesque,Lisa A1 - Li,Ruiqiang A1 - Lin,Chiao-Feng A1 - Lin,Michael F. A1 - Lindblad-Toh,Kerstin A1 - Llopart,Ana A1 - Long,Manyuan A1 - Low,Lloyd A1 - Lozovsky,Elena A1 - Lu,Jian A1 - Luo,Meizhong A1 - Machado,Carlos A. A1 - Makalowski,Wojciech A1 - Marzo,Mar A1 - Matsuda,Muneo A1 - Matzkin,Luciano A1 - McAllister,Bryant A1 - McBride,Carolyn S. A1 - McKernan,Brendan A1 - McKernan,Kevin A1 - Mendez-Lago,Maria A1 - Minx,Patrick A1 - Mollenhauer,Michael U. A1 - Montooth,Kristi A1 - Mount, Stephen M. A1 - Mu,Xu A1 - Myers,Eugene A1 - Negre,Barbara A1 - Newfeld,Stuart A1 - Nielsen,Rasmus A1 - Noor,Mohamed A. F. A1 - O'Grady,Patrick A1 - Pachter,Lior A1 - Papaceit,Montserrat A1 - Parisi,Matthew J. A1 - Parisi,Michael A1 - Parts,Leopold A1 - Pedersen,Jakob S. A1 - Pesole,Graziano A1 - Phillippy,Adam M A1 - Ponting,Chris P. A1 - Pop, Mihai A1 - Porcelli,Damiano A1 - Powell,Jeffrey R. A1 - Prohaska,Sonja A1 - Pruitt,Kim A1 - Puig,Marta A1 - Quesneville,Hadi A1 - Ram,Kristipati Ravi A1 - Rand,David A1 - Rasmussen,Matthew D. A1 - Reed,Laura K. A1 - Reenan,Robert A1 - Reily,Amy A1 - Remington,Karin A. A1 - Rieger,Tania T. A1 - Ritchie,Michael G. A1 - Robin,Charles A1 - Rogers,Yu-Hui A1 - Rohde,Claudia A1 - Rozas,Julio A1 - Rubenfield,Marc J. A1 - Ruiz,Alfredo A1 - Russo,Susan A1 - Salzberg,Steven L. A1 - Sanchez-Gracia,Alejandro A1 - Saranga,David J. A1 - Sato,Hajime A1 - Schaeffer,Stephen W. A1 - Schatz,Michael C A1 - Schlenke,Todd A1 - Schwartz,Russell A1 - Segarra,Carmen A1 - Singh,Rama S. A1 - Sirot,Laura A1 - Sirota,Marina A1 - Sisneros,Nicholas B. A1 - Smith,Chris D. A1 - Smith,Temple F. A1 - Spieth,John A1 - Stage,Deborah E. A1 - Stark,Alexander A1 - Stephan,Wolfgang A1 - Strausberg,Robert L. A1 - Strempel,Sebastian A1 - Sturgill,David A1 - Sutton,Granger A1 - Sutton,Granger G. A1 - Tao,Wei A1 - Teichmann,Sarah A1 - Tobari,Yoshiko N. A1 - Tomimura,Yoshihiko A1 - Tsolas,Jason M. A1 - Valente,Vera L. S. A1 - Venter,Eli A1 - Venter,J. Craig A1 - Vicario,Saverio A1 - Vieira,Filipe G. A1 - Vilella,Albert J. A1 - Villasante,Alfredo A1 - Walenz,Brian A1 - Wang,Jun A1 - Wasserman,Marvin A1 - Watts,Thomas A1 - Wilson,Derek A1 - Wilson,Richard K. A1 - Wing,Rod A. A1 - Wolfner,Mariana F. A1 - Wong,Alex A1 - Wong,Gane Ka-Shu A1 - Wu,Chung-I A1 - Wu,Gabriel A1 - Yamamoto,Daisuke A1 - Yang,Hsiao-Pei A1 - Yang,Shiaw-Pyng A1 - Yorke,James A. A1 - Yoshida,Kiyohito A1 - Zdobnov,Evgeny A1 - Zhang,Peili A1 - Zhang,Yu A1 - Zimin,Aleksey V. A1 - Baldwin,Jennifer A1 - Abdouelleil,Amr A1 - Abdulkadir,Jamal A1 - Abebe,Adal A1 - Abera,Brikti A1 - Abreu,Justin A1 - Acer,St Christophe A1 - Aftuck,Lynne A1 - Alexander,Allen A1 - An,Peter A1 - Anderson,Erica A1 - Anderson,Scott A1 - Arachi,Harindra A1 - Azer,Marc A1 - Bachantsang,Pasang A1 - Barry,Andrew A1 - Bayul,Tashi A1 - Berlin,Aaron A1 - Bessette,Daniel A1 - Bloom,Toby A1 - Blye,Jason A1 - Boguslavskiy,Leonid A1 - Bonnet,Claude A1 - Boukhgalter,Boris A1 - Bourzgui,Imane A1 - Brown,Adam A1 - Cahill,Patrick A1 - Channer,Sheridon A1 - Cheshatsang,Yama A1 - Chuda,Lisa A1 - Citroen,Mieke A1 - Collymore,Alville A1 - Cooke,Patrick A1 - Costello,Maura A1 - D'Aco,Katie A1 - Daza,Riza A1 - Haan,Georgius De A1 - DeGray,Stuart A1 - DeMaso,Christina A1 - Dhargay,Norbu A1 - Dooley,Kimberly A1 - Dooley,Erin A1 - Doricent,Missole A1 - Dorje,Passang A1 - Dorjee,Kunsang A1 - Dupes,Alan A1 - Elong,Richard A1 - Falk,Jill A1 - Farina,Abderrahim A1 - Faro,Susan A1 - Ferguson,Diallo A1 - Fisher,Sheila A1 - Foley,Chelsea D. A1 - Franke,Alicia A1 - Friedrich,Dennis A1 - Gadbois,Loryn A1 - Gearin,Gary A1 - Gearin,Christina R. A1 - Giannoukos,Georgia A1 - Goode,Tina A1 - Graham,Joseph A1 - Grandbois,Edward A1 - Grewal,Sharleen A1 - Gyaltsen,Kunsang A1 - Hafez,Nabil A1 - Hagos,Birhane A1 - Hall,Jennifer A1 - Henson,Charlotte A1 - Hollinger,Andrew A1 - Honan,Tracey A1 - Huard,Monika D. A1 - Hughes,Leanne A1 - Hurhula,Brian A1 - Husby,M Erii A1 - Kamat,Asha A1 - Kanga,Ben A1 - Kashin,Seva A1 - Khazanovich,Dmitry A1 - Kisner,Peter A1 - Lance,Krista A1 - Lara,Marcia A1 - Lee,William A1 - Lennon,Niall A1 - Letendre,Frances A1 - LeVine,Rosie A1 - Lipovsky,Alex A1 - Liu,Xiaohong A1 - Liu,Jinlei A1 - Liu,Shangtao A1 - Lokyitsang,Tashi A1 - Lokyitsang,Yeshi A1 - Lubonja,Rakela A1 - Lui,Annie A1 - MacDonald,Pen A1 - Magnisalis,Vasilia A1 - Maru,Kebede A1 - Matthews,Charles A1 - McCusker,William A1 - McDonough,Susan A1 - Mehta,Teena A1 - Meldrim,James A1 - Meneus,Louis A1 - Mihai,Oana A1 - Mihalev,Atanas A1 - Mihova,Tanya A1 - Mittelman,Rachel A1 - Mlenga,Valentine A1 - Montmayeur,Anna A1 - Mulrain,Leonidas A1 - Navidi,Adam A1 - Naylor,Jerome A1 - Negash,Tamrat A1 - Nguyen,Thu A1 - Nguyen,Nga A1 - Nicol,Robert A1 - Norbu,Choe A1 - Norbu,Nyima A1 - Novod,Nathaniel A1 - O'Neill,Barry A1 - Osman,Sahal A1 - Markiewicz,Eva A1 - Oyono,Otero L. A1 - Patti,Christopher A1 - Phunkhang,Pema A1 - Pierre,Fritz A1 - Priest,Margaret A1 - Raghuraman,Sujaa A1 - Rege,Filip A1 - Reyes,Rebecca A1 - Rise,Cecil A1 - Rogov,Peter A1 - Ross,Keenan A1 - Ryan,Elizabeth A1 - Settipalli,Sampath A1 - Shea,Terry A1 - Sherpa,Ngawang A1 - Shi,Lu A1 - Shih,Diana A1 - Sparrow,Todd A1 - Spaulding,Jessica A1 - Stalker,John A1 - Stange-Thomann,Nicole A1 - Stavropoulos,Sharon A1 - Stone,Catherine A1 - Strader,Christopher A1 - Tesfaye,Senait A1 - Thomson,Talene A1 - Thoulutsang,Yama A1 - Thoulutsang,Dawa A1 - Topham,Kerri A1 - Topping,Ira A1 - Tsamla,Tsamla A1 - Vassiliev,Helen A1 - Vo,Andy A1 - Wangchuk,Tsering A1 - Wangdi,Tsering A1 - Weiand,Michael A1 - Wilkinson,Jane A1 - Wilson,Adam A1 - Yadav,Shailendra A1 - Young,Geneva A1 - Yu,Qing A1 - Zembek,Lisa A1 - Zhong,Danni A1 - Zimmer,Andrew A1 - Zwirko,Zac A1 - Jaffe,David B. A1 - Alvarez,Pablo A1 - Brockman,Will A1 - Butler,Jonathan A1 - Chin,CheeWhye A1 - Gnerre,Sante A1 - Grabherr,Manfred A1 - Kleber,Michael A1 - Mauceli,Evan A1 - MacCallum,Iain AB - Comparative analysis of multiple genomes in a phylogenetic framework dramatically improves the precision and sensitivity of evolutionary inference, producing more robust results than single-genome analyses can provide. The genomes of 12 Drosophila species, ten of which are presented here for the first time (sechellia, simulans, yakuba, erecta, ananassae, persimilis, willistoni, mojavensis, virilis and grimshawi), illustrate how rates and patterns of sequence divergence across taxa can illuminate evolutionary processes on a genomic scale. These genome sequences augment the formidable genetic tools that have made Drosophila melanogaster a pre-eminent model for animal genetics, and will further catalyse fundamental research on mechanisms of development, cell biology, genetics, disease, neurobiology, behaviour, physiology and evolution. Despite remarkable similarities among these Drosophila species, we identified many putatively non-neutral changes in protein-coding genes, non-coding RNA genes, and cis-regulatory regions. These may prove to underlie differences in the ecology and behaviour of these diverse species. VL - 450 SN - 0028-0836 UR - http://www.nature.com/nature/journal/v450/n7167/full/nature06341.html CP - 7167 M3 - 10.1038/nature06341 ER - TY - JOUR T1 - Execution time analysis of a top-down R-tree construction algorithm JF - Information Processing Letters Y1 - 2007 A1 - Alborzi,Houman A1 - Samet, Hanan KW - Bulk loading KW - Data structures KW - Packing KW - R-trees KW - Spatial databases AB - A detailed CPU execution-time analysis and implementation are given for a bulk loading algorithm to construct R-trees due to García et al. [Y.J. García, M.A. López, S.T. Leutenegger, A greedy algorithm for bulk loading R-trees, in: GIS'98: Proc. of the 6th ACM Intl. Symp. on Advances in Geographic Information Systems, Washington, DC, 1998, pp. 163–164] which is known as the top-down greedy split (TGS) bulk loading algorithm. The TGS algorithm makes use of a classical bottom-up packing approach. In addition, an alternative packing approach termed top-down packing is introduced which may lead to improved query performance, and it is shown how to incorporate it into the TGS algorithm. A discussion is also presented of the tradeoffs of using the bottom-up and top-down packing approaches. VL - 101 SN - 0020-0190 UR - http://www.sciencedirect.com/science/article/pii/S002001900600233X CP - 1 M3 - 10.1016/j.ipl.2006.07.010 ER - TY - JOUR T1 - Experimenting with software testbeds for evaluating new technologies JF - Empirical Software Engineering Y1 - 2007 A1 - Lindvall,M. A1 - Rus,I. A1 - Donzelli,P. A1 - Memon, Atif M. A1 - Zelkowitz, Marvin V A1 - Betin-Can,A. A1 - Bultan,T. A1 - Ackermann,C. A1 - Anders,B. A1 - Asgari, S. A1 - Basili, Victor R. AB - The evolution of a new technology depends upon a good theoretical basis for developing the technology, as well as upon its experimental validation. In order to provide for this experimentation, we have investigated the creation of a software testbed and the feasibility of using the same testbed for experimenting with a broad set of technologies. The testbed is a set of programs, data, and supporting documentation that allows researchers to test their new technology on a standard software platform. An important component of this testbed is the Unified Model of Dependability (UMD), which was used to elicit dependability requirements for the testbed software. With a collection of seeded faults and known issues of the target system, we are able to determine if a new technology is adept at uncovering defects or providing other aids proposed by its developers. In this paper, we present the Tactical Separation Assisted Flight Environment (TSAFE) testbed environment for which we modeled and evaluated dependability requirements and defined faults to be seeded for experimentation. We describe two completed experiments that we conducted on the testbed. The first experiment studies a technology that identifies architectural violations and evaluates its ability to detect the violations. The second experiment studies model checking as part of design for verification. We conclude by describing ongoing experimental work studying testing, using the same testbed. Our conclusion is that even though these three experiments are very different in terms of the studied technology, using and re-using the same testbed is beneficial and cost effective. VL - 12 CP - 4 M3 - 10.1007/s10664-006-9034-0 ER - TY - JOUR T1 - Face and Gesture Recognition-Appearance Characterization of Linear Lambertian Objects, Generalized Photometric Stereo, and Illumination-Invariant Face Recognition JF - IEEE Transactions on Pattern Analysis and Machine Intelligence Y1 - 2007 A1 - Zhou,S. K A1 - Aggarwal,G. A1 - Chellapa, Rama A1 - Jacobs, David W. VL - 29 CP - 2 ER - TY - JOUR T1 - GATA and Nkx factors synergistically regulate tissue-specific gene expression and development in vivo JF - Development Y1 - 2007 A1 - Zhang,Yuzhen A1 - Rath,Nibedita A1 - Hannenhalli, Sridhar A1 - Wang,Zhishan A1 - Cappola,Thomas A1 - Kimura,Shioko A1 - Atochina-Vasserman,Elena A1 - Lu,Min Min A1 - Beers,Michael F. A1 - Morrisey,Edward E. AB - In vitro studies have suggested that members of the GATA and Nkx transcription factor families physically interact, and synergistically activate pulmonary epithelial- and cardiac-gene promoters. However, the relevance of this synergy has not been demonstrated in vivo. We show that Gata6-Titf1 (Gata6-Nkx2.1) double heterozygous (G6-Nkx DH) embryos and mice have severe defects in pulmonary epithelial differentiation and distal airway development, as well as reduced phospholipid production. The defects in G6-Nkx DH embryos and mice are similar to those observed in human neonates with respiratory distress syndromes, including bronchopulmonary dysplasia, and differential gene expression analysis reveals essential developmental pathways requiring synergistic regulation by both Gata6 and Titf1 (Nkx2.1). These studies indicate that Gata6 and Nkx2.1 act in a synergistic manner to direct pulmonary epithelial differentiation and development in vivo, providing direct evidence that interactions between these two transcription factor families are crucial for the development of the tissues in which they are co-expressed. VL - 134 UR - http://dev.biologists.org/content/134/1/189.abstract CP - 1 M3 - 10.1242/dev.02720 ER - TY - CONF T1 - A general framework for reasoning about inconsistency T2 - Proceedings of the International Joint Conference on Artificial Intelligence Y1 - 2007 A1 - V.S. Subrahmanian A1 - Amgoud,L. AB - Numerous logics have been developed for reason-ing about inconsistency which differ in (i) the logic to which they apply, and (ii) the criteria used to draw inferences. In this paper, we propose a gen- eral framework for reasoning about inconsistency in a wide variety of logics including ones for which inconsistency resolution methods have not yet been studied (e.g. various temporal and epistemic log- ics). We start with Tarski and Scott’s axiomatiza- tion of logics, but drop their monotonicity require- ments that we believe are too strong for AI. For such a logic L, we define the concept of an option. Options are sets of formulas in L that are closed and consistent according to the notion of consequence and consistency in L. We show that by defining an appropriate preference relation on options, we can capture several existing works such as Brewka’s subtheories. We also provide algorithms to com- pute most preferred options. JA - Proceedings of the International Joint Conference on Artificial Intelligence ER - TY - JOUR T1 - Genome Analysis Linking Recent European and African Influenza (H5N1) Viruses JF - Emerging Infectious DiseasesEmerg Infect Dis Y1 - 2007 A1 - Salzberg,Steven L. A1 - Kingsford, Carl A1 - Cattoli,Giovanni A1 - Spiro,David J. A1 - Janies,Daniel A. A1 - Aly,Mona Mehrez A1 - Brown,Ian H. A1 - Couacy-Hymann,Emmanuel A1 - De Mia,Gian Mario A1 - Dung,Do Huu A1 - Guercio,Annalisa A1 - Joannis,Tony A1 - Ali,Ali Safar Maken A1 - Osmani,Azizullah A1 - Padalino,Iolanda A1 - Saad,Magdi D. A1 - Savić,Vladimir A1 - Sengamalay,Naomi A. A1 - Yingst,Samuel A1 - Zaborsky,Jennifer A1 - Zorman-Rojs,Olga A1 - Ghedin,Elodie A1 - Capua,Ilaria AB - Although linked, these viruses are distinct from earlier outbreak strains., To better understand the ecology and epidemiology of the highly pathogenic avian influenza virus in its transcontinental spread, we sequenced and analyzed the complete genomes of 36 recent influenza A (H5N1) viruses collected from birds in Europe, northern Africa, and southeastern Asia. These sequences, among the first complete genomes of influenza (H5N1) viruses outside Asia, clearly depict the lineages now infecting wild and domestic birds in Europe and Africa and show the relationships among these isolates and other strains affecting both birds and humans. The isolates fall into 3 distinct lineages, 1 of which contains all known non-Asian isolates. This new Euro-African lineage, which was the cause of several recent (2006) fatal human infections in Egypt and Iraq, has been introduced at least 3 times into the European-African region and has split into 3 distinct, independently evolving sublineages. One isolate provides evidence that 2 of these sublineages have recently reassorted. VL - 13 SN - 1080-6040 CP - 5 M3 - 10.3201/eid1305.070013 ER - TY - CONF T1 - Grow and Know: Understanding Record-keeping Needs for Tracking the Development of Young Children T2 - SIGCHI '07 Y1 - 2007 A1 - Kientz, Julie A. A1 - Arriaga, Rosa I. A1 - Marshini Chetty A1 - Hayes, Gillian R. A1 - Richardson, Jahmeilah A1 - Patel, Shwetak N. A1 - Abowd, Gregory D. KW - children KW - design requirements KW - developmental delay KW - healthcare KW - qualitative study AB - From birth through age five, children undergo rapid development and learn skills that will influence them their entire lives. Regular visits to the pediatrician and detailed record-keeping can ensure that children are progressing and can identify early warning signs of developmental delay or disability. However, new parents are often overwhelmed with new responsibilities, and we believe there is an opportunity for computing technology to assist in this process. In this paper, we present a qualitative study aimed at uncovering some specific needs for record-keeping and analysis for new parents and their network of caregivers. Through interviews and focus groups, we have confirmed assumptions about the rationales parents have and the functions required for using technology for record-keeping. We also identify new themes, potential prototypes, and design guidelines for this domain. JA - SIGCHI '07 T3 - CHI '07 PB - ACM SN - 978-1-59593-593-9 UR - http://doi.acm.org/10.1145/1240624.1240830 ER - TY - CONF T1 - Holding the Internet Accountable T2 - Proc. 6th ACM Workshop on Hot Topics in Networks (Hotnets-VI) Y1 - 2007 A1 - Andersen,David A1 - Balakrishnan,Hari A1 - Feamster, Nick A1 - Koponen,Teemu A1 - Moon,Daekyong A1 - Shenker,Scott AB - Today’s IP network layer provides little to no protection against misconfiguration or malice. Despite some progress in improving the robustness and security of the IP layer, misconfigurations and attacks still occur frequently. We show how a network layer that provides accountability, i.e., the ability to associate each action with the responsible entity, provides a firm foundation for defenses against misconfiguration and malice. We present the design of a network layer that incorporates accountability called AIP (Accountable Internet Protocol) and show how its features—notably, its use of self-certifying addresses— can improve both source accountability (the ability to trace actions to a particular end host and stop that host from misbehaving) and control-plane accountability (the ability to pinpoint and prevent attacks on routing). JA - Proc. 6th ACM Workshop on Hot Topics in Networks (Hotnets-VI) UR - http://repository.cmu.edu/compsci/66 ER - TY - CONF T1 - Hood College, Master of Business Administration, 2005 Hood College, Master of Science (Computer Science), 2001 Hood College, Bachelor of Science (Computer Science), 1998 Frederick Community College, Associate in Arts (Business Administration), 1993 T2 - Proceedings of the Workshop on Metareasoning in Agent-Based Systems Y1 - 2007 A1 - Anderson,M. L A1 - Schmill,M. A1 - Oates,T. A1 - Perlis, Don A1 - Josyula,D. A1 - Wright,D. A1 - Human,S. W.T.D.N A1 - Metacognition,L. A1 - Fults,S. A1 - Josyula,D. P JA - Proceedings of the Workshop on Metareasoning in Agent-Based Systems ER - TY - CHAP T1 - How Smart Homes Learn: The Evolution of the Networked Home and Household T2 - UbiComp 2007: Ubiquitous Computing Y1 - 2007 A1 - Marshini Chetty A1 - Sung, Ja-Young A1 - Grinter, Rebecca E. ED - Krumm, John ED - Abowd, Gregory D. ED - Seneviratne, Aruna ED - Strang, Thomas KW - Computer Communication Networks KW - computers and society KW - home networking KW - Information Systems Applications (incl.Internet) KW - infrastructure KW - smart home KW - software engineering KW - Systems and Data Security KW - User Interfaces and Human Computer Interaction AB - Despite a growing desire to create smart homes, we know little about how networked technologies interact with a house’s infrastructure. In this paper, we begin to close this gap by presenting findings from a study that examined the relationship between home networking and the house itself—and the work that results for householders as a consequence of this interaction. We discuss four themes that emerged: an ambiguity in understanding the virtual boundaries created by wireless networks, the home network control paradox, a new home network access paradox, and the relationship between increased responsibilities and the possibilities of wireless networking. JA - UbiComp 2007: Ubiquitous Computing T3 - Lecture Notes in Computer Science PB - Springer Berlin Heidelberg SN - 978-3-540-74852-6, 978-3-540-74853-3 UR - http://link.springer.com/chapter/10.1007/978-3-540-74853-3_8 ER - TY - CHAP T1 - Human Values for Shaping the Made World T2 - Human-Computer Interaction – INTERACT 2007Human-Computer Interaction – INTERACT 2007 Y1 - 2007 A1 - Shneiderman, Ben ED - Baranauskas,Cécilia ED - Palanque,Philippe ED - Abascal,Julio ED - Barbosa,Simone AB - Interface design principles have been effective in shaping new desktop applications, web-based resources, and mobile devices. Usability and sociability promote successful online communities and social network services. The contributions of human-computer interaction researchers have been effective in raising the quality of design of many products and services. As our influence grows, we can play an even more profound role in guaranteeing that enduring human values are embedded in the next generation of technology. This talk identifies which goals are realistic, such as universality, responsibility, trust, empathy, and privacy, and how we might ensure that they become part of future services and systems. JA - Human-Computer Interaction – INTERACT 2007Human-Computer Interaction – INTERACT 2007 T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 4662 SN - 978-3-540-74794-9 UR - http://dx.doi.org/10.1007/978-3-540-74796-3_1 ER - TY - CONF T1 - Investigation of Revolute Joint Clearances Created by an In-Mold Assembly Process Y1 - 2007 A1 - Ananthanarayanan,A. A1 - Thamire,C. A1 - Gupta,S.K. KW - acrylonitrile butadiene styrene insert KW - aluminum mold KW - assembling KW - couplings KW - cycle time reduction KW - heat transfer KW - injection moulding KW - inmold assembly process KW - mold deformation KW - molding process KW - moulding equipment KW - part count reduction KW - plastics industry KW - revolute joint clearances AB - Revolute joints are frequently used in articulated structures. Traditionally, such a joint is formed by assembling two components. As an alternative, revolute joints can be created inside the mold using an in-mold assembly process. This process eliminates the need for post-molding assembly, thus significantly reducing the cycle time and part count. The functional performance of a revolute joint depends on the clearance in the joint. The clearance in turn depends on the part shrinkage and the mold deformation during the molding process. The presence of a polymer part during the second molding stage makes an in-mold assembly process significantly different from the traditional molding process due to the difference in heat transfer and deformation characteristics. This paper presents experimental data and a preliminary model to explain the differences in clearance produced by an aluminum mold and an Aluminum mold with an Acrylonitrile butadiene styrene (ABS) insert. Our data indicates that there is a significant difference between the clearances observed from these two different types of molds. We believe that clearances produced depend strongly on the thermal history of the parts. M3 - 10.1109/ISAM.2007.4288458 ER - TY - JOUR T1 - A Language for Human Action JF - Computer Y1 - 2007 A1 - Guerra-Filho,G. A1 - Aloimonos, J. KW - anthropocentric system KW - artificial agent KW - Artificial intelligence KW - cognitive model KW - Concrete KW - Databases KW - human action KW - human activity language KW - Human computer interaction KW - human factors KW - human sensory-motor skill KW - human-centered computing KW - human-machine interaction KW - HUMANS KW - Intelligent sensors KW - linguistic framework KW - linguistics KW - Mirrors KW - Morphology KW - natural language KW - natural languages KW - Neurons KW - Power system modeling KW - user interface KW - User interfaces AB - Human-centered computing (HCC) involves conforming computer technology to humans while naturally achieving human-machine interaction. In a human-centered system, the interaction focuses on human requirements, capabilities, and limitations. These anthropocentric systems also focus on the consideration of human sensory-motor skills in a wide range of activities. This ensures that the interface between artificial agents and human users accounts for perception and action in a novel interaction paradigm. In turn, this leads to behavior understanding through cognitive models that allow content description and, ultimately, the integration of real and virtual worlds. Our work focuses on building a language that maps to the lower-level sensory and motor languages and to the higher-level natural language. An empirically demonstrated human activity language provides sensory-motor-grounded representations for understanding human actions. A linguistic framework allows the analysis and synthesis of these actions. VL - 40 SN - 0018-9162 CP - 5 M3 - 10.1109/MC.2007.154 ER - TY - CONF T1 - MAGIC: A Multi-Activity Graph Index for Activity Detection T2 - Information Reuse and Integration, 2007. IRI 2007. IEEE International Conference on Y1 - 2007 A1 - Albanese, M. A1 - Pugliese, A. A1 - V.S. Subrahmanian A1 - Udrea,O. KW - complexity;graph KW - detection;complexity KW - graph KW - index;probability KW - MAGIC;activity KW - reducing KW - restrictions;exponential KW - theory;probability; KW - threshold;computational KW - time;multiactivity AB - Suppose we are given a set A of activities of interest, a set O of observations, and a probability threshold p. We are interested in finding the set of all pairs (a, O'), where a epsi A and O' sube O, that minimally validate the fact that an instance of activity a occurs in O with probability p or more. The novel contribution of this paper is the notion of the multi-activity graph index (MAGIC), which can index very large numbers of observations from interleaved activities and quickly retrieve completed instances of the monitored activities. We introduce two complexity reducing restrictions of the problem (which takes exponential time) and develop algorithms for each. We experimentally evaluate our exponential algorithm as well as the restricted algorithms on both synthetic data and a real (depersonalized) travel data set consisting of 5.5 million observations. Our experiments show that MAGIC consumes reasonable amounts of memory and can retrieve completed instances of activities in just a few seconds. We also report appropriate statistical significance results validating our experimental hypotheses. JA - Information Reuse and Integration, 2007. IRI 2007. IEEE International Conference on M3 - 10.1109/IRI.2007.4296632 ER - TY - CONF T1 - Measuring variability in sentence ordering for news summarization T2 - Proceedings of the Eleventh European Workshop on Natural Language Generation Y1 - 2007 A1 - Madnani,Nitin A1 - Passonneau,Rebecca A1 - Ayan,Necip Fazil A1 - Conroy,John M. A1 - Dorr, Bonnie J A1 - Klavans,Judith L. A1 - O'Leary, Dianne P. A1 - Schlesinger,Judith D. AB - The issue of sentence ordering is an important one for natural language tasks such as multi-document summarization, yet there has not been a quantitative exploration of the range of acceptable sentence orderings for short texts. We present results of a sentence reordering experiment with three experimental conditions. Our findings indicate a very high degree of variability in the orderings that the eighteen subjects produce. In addition, the variability of reorderings is significantly greater when the initial ordering seen by subjects is different from the original summary. We conclude that evaluation of sentence ordering should use multiple reference orderings. Our evaluation presents several metrics that might prove useful in assessing against multiple references. We conclude with a deeper set of questions: (a) what sorts of independent assessments of quality of the different reference orderings could be made and (b) whether a large enough test set would obviate the need for such independent means of quality assessment. JA - Proceedings of the Eleventh European Workshop on Natural Language Generation T3 - ENLG '07 PB - Association for Computational Linguistics CY - Stroudsburg, PA, USA UR - http://dl.acm.org/citation.cfm?id=1610163.1610177 ER - TY - CONF T1 - MobCast: Overlay Architecture for Seamless IP Mobility using Scalable Anycast Proxies T2 - Wireless Communications and Networking Conference, 2007.WCNC 2007. IEEE Y1 - 2007 A1 - Lee,C.P. A1 - Attrey,K. A1 - Caballero,C. A1 - Feamster, Nick A1 - Mihail,M. A1 - Copeland,J.A. KW - address space KW - handoff-speed KW - IP networks KW - MobCast KW - mobile hosts KW - mobile radio KW - overlay architecture KW - proxy location KW - routing overlay system KW - scalable anycast proxies KW - seamless IP mobility KW - telecommunication network routing KW - universal IP address AB - We propose a routing overlay system, MobCast, for simple and efficient routing to mobile hosts. Mobcast nodes advertise the same address space at each proxy location, and each mobile host is assigned a "universal" IP address from this address space, so packets sent to a mobile host's universal IP address automatically go to the nearest proxy on the overlay. The overlay then delivers the packets to the mobile host. Our architecture enables seamless mobility for both micro and macro mobility. While our initial design is not as mature as Mobile IP, it shows great promise to solve the traditional problems of ingress routing, firewalls, NATs, and rapid mobility with much lower complexity. We present our design as a scalable and deployable alternative to mobile IP. In this paper, we focus on describing the MobCast system architecture. We form our arguments for scalability, handoff-speed, and simplicity, and give our initial results for scalability. We postpone a detailed discussion of MobCast's security model for future work. JA - Wireless Communications and Networking Conference, 2007.WCNC 2007. IEEE M3 - 10.1109/WCNC.2007.708 ER - TY - JOUR T1 - Multiple alternative sentence compressions for automatic text summarization JF - Proceedings of DUC Y1 - 2007 A1 - Madnani,N. A1 - Zajic, David A1 - Dorr, Bonnie J A1 - Ayan,N.F. A1 - Jimmy Lin AB - We perform multi-document summariza-tion by generating compressed versions of source sentences as summary candi- dates and using weighted features of these candidates to construct summaries. We combine a parse-and-trim approach with a novel technique for producing multiple alternative compressions for source sen- tences. In addition, we use a novel method for tuning the feature weights that maxi- mizes the change in the ROUGE-2 score (∆ROUGE) between the already existing summary state and the new state that re- sults from the addition of the candidate under consideration. We also describe ex- periments using a new paraphrase-based feature for redundancy checking. Finally, we present the results of our DUC2007 submissions and some ideas for future work. ER - TY - CONF T1 - Multiple View Image Reconstruction: A Harmonic Approach T2 - IEEE Conference on Computer Vision and Pattern Recognition, 2007. CVPR '07 Y1 - 2007 A1 - Domke, J. A1 - Aloimonos, J. KW - CAMERAS KW - filtering theory KW - Geometry KW - Harmonic analysis KW - Image reconstruction KW - imaging process geometry KW - Information filtering KW - Joining processes KW - Low pass filters KW - low-pass filter KW - low-pass filters KW - multiple view image reconstruction KW - Position measurement KW - Power harmonic filters KW - surface reconstruction AB - This paper presents a new constraint connecting the signals in multiple views of a surface. The constraint arises from a harmonic analysis of the geometry of the imaging process and it gives rise to a new technique for multiple view image reconstruction. Given several views of a surface from different positions, fundamentally different information is present in each image, owing to the fact that cameras measure the incoming light only after the application of a low-pass filter. Our analysis shows how the geometry of the imaging is connected to this filtering. This leads to a technique for constructing a single output image containing all the information present in the input images. JA - IEEE Conference on Computer Vision and Pattern Recognition, 2007. CVPR '07 PB - IEEE SN - 1-4244-1180-7 M3 - 10.1109/CVPR.2007.383285 ER - TY - JOUR T1 - New records of phytoplankton for Bangladesh. 3. Volvocales JF - Bangladesh Journal of Plant Taxonomy Y1 - 2007 A1 - Khondker,Moniruzzaman A1 - Bhuiyan,Rauf Ahmed A1 - Yeasmin,Jenat A1 - Alam,Munirul A1 - Sack,R. Bradley A1 - Huq,Anwar A1 - Rita R Colwell AB - This study presents 21 species of Chlamydomonas, four species of Carteria, two species of each of Nephroselmis, Pyramidomonas and Scherffelia, and Collodictyon triciliatum, Polytoma minus, Tetrachloridium ? allorgei and Tetraselmis cordiformis. These species have been reported from some ponds of Mathbaria of Pirojpur and Bakerganj of Barisal districts in Bangladesh. VL - 14 SN - 1028-2092 UR - http://www.banglajol.info/bd/index.php/BJPT/article/viewArticle/518 CP - 1 M3 - 10.3329/bjpt.v14i1.518 ER - TY - JOUR T1 - New records of phytoplankton for Bangladesh. 4. Chlorococcales JF - Bangladesh Journal of Plant Taxonomy Y1 - 2007 A1 - Khondker,Moniruzzaman A1 - Bhuiyan,Rauf Ahmed A1 - Yeasim,Jenat A1 - Alam,Munirul A1 - Sack,R. Bradley A1 - Huq,Anwar A1 - Rita R Colwell AB - This study presents three species from each of Schroederia, Monoraphidium and Ankistrodesmus, two species and one variety of Dictyosphaerium, two varieties of Pediastrum, and Tetraedron arthrodesmiforme var. contorta, Chlorotetraedron polymorphum, Myrmecia aquatica, Oocystis tainoensis, Nephrocytium spirale, Kirchneriella irregularis, Coelastrum indicum and Scenedesmus similagineus. These taxa have been reported from some ponds of Mathbaria of Pirojpur and Bakerganj of Barisal Districts in Bangladesh. VL - 14 SN - 1028-2092 UR - http://www.banglajol.info/bd/index.php/BJPT/article/viewArticle/528 CP - 2 M3 - 10.3329/bjpt.v14i2.528 ER - TY - CONF T1 - Ontologies for reasoning about failures in AI systems T2 - Proceedings from the Workshop on Metareasoning in Agent Based Systems at the Sixth International Joint Conference on Autonomous Agents and Multiagent Sytems Y1 - 2007 A1 - Schmill,M. A1 - Josyula,D. A1 - Anderson,M. L A1 - Wilson,S. A1 - Oates,T. A1 - Perlis, Don A1 - Fults,S. JA - Proceedings from the Workshop on Metareasoning in Agent Based Systems at the Sixth International Joint Conference on Autonomous Agents and Multiagent Sytems ER - TY - JOUR T1 - Optimal expected-case planar point location JF - SIAM Journal on Computing Y1 - 2007 A1 - Arya,S. A1 - Malamatos,T. A1 - Mount, Dave A1 - Wong,K.C. AB - Point location is the problem of preprocessing a planar polygonal subdivision S of size ninto a data structure in order to determine efficiently the cell of the subdivision that contains a given query point. We consider this problem from the perspective of expected query time. We are given the probabilities pz that the query point lies within each cell z ∈ S. The entropy H of the resulting discrete probability distribution is the dominant term in the lower bound on the expected-case query time. We show that it is possible to achieve query time H + O( √ H + 1) with space O(n), which is optimal up to lower order terms in the query time. We extend this result to subdivisions with convex cells, assuming a uniform query distribution within each cell. In order to achieve space efficiency, we introduce the concept of entropy-preserving cuttings. VL - 37 CP - 2 ER - TY - CONF T1 - Performance Measurement of Novice HPC Programmers Code T2 - Proceedings of the 3rd International Workshop on Software Engineering for High Performance Computing Applications Y1 - 2007 A1 - Alameh, Rola A1 - Zazworka, Nico A1 - Hollingsworth, Jeffrey K KW - measurement KW - performance KW - performance measures KW - product metrics KW - program analysis AB - Performance is one of the key factors of improving productivity in High Performance Computing (HPC). In this paper we discuss current studies in the field of performance measurement of codes captured in classroom experiments for the High Productivity Computing Project (HPCS). We give two examples of measurements introducing two new hypotheses: spending more effort doesn't always result in improvement of performance for novices; the use of higher level MPI functions promises better performance for novices. We also present a tool - the Automated Performance Measurement System (APMS). APMS helps to partially automate the measurement of the performance of a set of parallel programs with several inputs. The design and implementation of the tool is flexible enough to allow other researchers to conduct similar studies. JA - Proceedings of the 3rd International Workshop on Software Engineering for High Performance Computing Applications T3 - SE-HPC '07 PB - IEEE Computer Society SN - 0-7695-2969-0 UR - http://dx.doi.org/10.1109/SE-HPC.2007.4 M3 - http://dx.doi.org/10.1109/SE-HPC.2007.4 ER - TY - JOUR T1 - Pointerless implementation of hierarchical simplicial meshes and efficient neighbor finding in arbitrary dimensions JF - International Journal of Computational Geometry and Applications Y1 - 2007 A1 - Atalay,F. B A1 - Mount, Dave A1 - Mitchell,J. AB - We describe a pointerless representation of hierarchical regular simplicial meshes, basedon a bisection approach proposed by Maubach. We introduce a new labeling scheme, called an LPT code, which uniquely encodes the geometry of each simplex of the hi- erarchy, and we present rules to compute the neighbors of a given simplex efficiently through the use of these codes. In addition, we show how to traverse the associated tree and how to answer point location and interpolation queries. Our system works in arbitrary dimensions. VL - 17 CP - 6 ER - TY - JOUR T1 - Principles for designing data-/compute-intensive distributed applications and middleware systems for heterogeneous environments JF - Journal of Parallel and Distributed Computing Y1 - 2007 A1 - Kim,Jik-Soo A1 - Andrade,Henrique A1 - Sussman, Alan KW - Computational science applications KW - Data-/compute-intensive applications KW - Heterogeneous environments KW - Middleware systems AB - The nature of distributed systems is constantly and steadily changing as the hardware and software landscape evolves. Porting applications and adapting existing middleware systems to ever changing computational platforms has become increasingly complex and expensive. Therefore, the design of applications, as well as the design of next generation middleware systems, must follow a set of guiding principles in order to insure long-term “survivability” without costly re-engineering. From our practical experience, the key determinants to success in this endeavor are adherence to the following principles: (1) Design for change; (2) Provide for storage subsystem I/O coordination; (3) Employ workload partitioning and load balancing techniques; (4) Employ caching; (5) Schedule the workload; and (6) Understand the workload. In order to support these principles, we have collected extensive experimental results comparing three middleware systems targeted at data- and compute-intensive applications implemented by our research group during the course of the last decade, on a single data- and compute-intensive application. The main contribution of this work is the analysis of a level playing field, where we discuss and quantify how adherence to these guiding principles impacts overall system throughput and response time. VL - 67 SN - 0743-7315 UR - http://www.sciencedirect.com/science/article/pii/S0743731507000603 CP - 7 M3 - 10.1016/j.jpdc.2007.04.006 ER - TY - JOUR T1 - A probabilistic framework for correspondence and egomotion JF - Dynamical Vision Y1 - 2007 A1 - Domke, J. A1 - Aloimonos, J. ER - TY - JOUR T1 - A probabilistic notion of camera geometry: Calibrated vs. uncalibrated JF - PHOTOGRAMMETRIE FERNERKUNDUNG GEOINFORMATION Y1 - 2007 A1 - Domke, J. A1 - Aloimonos, J. VL - 2007 CP - 1 ER - TY - CONF T1 - Reactive Query Policies: A Formalism for Planning with Volatile External Information Y1 - 2007 A1 - Au,Tsz-Chiu A1 - Nau, Dana S. KW - data collection KW - data mining KW - information volatility KW - planning (artificial intelligence) KW - planning system KW - presumptive strategy KW - query management KW - Query processing KW - reactive query policies KW - volatile external information AB - To generate plans for collecting data for data mining, an important problem is information volatility during planning: the information needed by the planning system may change or expire during the planning process, as changes occur in the data being collected. In such situations, the planning system faces two challenges: how to generate plans despite these changes, and how to guarantee that a plan returned by the planner will remain valid for some period of time after the planning ends. The focus of our work is to address both of the above challenges. In particular, we provide: 1) A formalism for reactive query policies, a class of strategies for deciding when to reissue queries for information that has changed during the planning process. This class includes all query management strategies that have yet been developed. 2) A new reactive query policy called the presumptive strategy. In our experiments, the presumptive strategy ran exponentially faster than the lazy strategy, the best previously known query management strategy. In the hardest set of problems we tested, the presumptive strategy took 4.7% as much time and generated 6.9% as many queries as the lazy strategy M3 - 10.1109/CIDM.2007.368880 ER - TY - CHAP T1 - Recognizing Faces Across Age Progression T2 - Face Biometrics for Personal IdentificationFace Biometrics for Personal Identification Y1 - 2007 A1 - Ramanathan,Narayanan A1 - Chellapa, Rama ED - Hammoud,Riad ED - Abidi,Besma ED - Abidi,Mongi JA - Face Biometrics for Personal IdentificationFace Biometrics for Personal Identification T3 - Signals and Communication Technology PB - Springer Berlin Heidelberg SN - 978-3-540-49346-4 UR - http://dx.doi.org/10.1007/978-3-540-49346-4_3 ER - TY - JOUR T1 - A roadmap to the integration of early visual modules JF - International Journal of Computer Vision Y1 - 2007 A1 - Ogale, A. S A1 - Aloimonos, J. VL - 72 CP - 1 ER - TY - JOUR T1 - Robust appearance modeling for pedestrian and vehicle tracking JF - Multimodal Technologies for Perception of Humans Y1 - 2007 A1 - Abd-Almageed, Wael A1 - Davis, Larry S. AB - This paper describes a system for tracking people and vehicles for stationary-camera visual surveillance. The appearance of objects being tracked is modeled using mixtures of mixtures of Gaussians. Particles filters are used to track the states of object. Results show the robustness of the system to various lighting and object conditions. ER - TY - CONF T1 - Similarity-Based Forecasting with Simultaneous Previews: A River Plot Interface for Time Series Forecasting T2 - Information Visualization, 2007. IV '07. 11th International Conference Y1 - 2007 A1 - Buono,P. A1 - Plaisant, Catherine A1 - Simeone,A. A1 - Aris,A. A1 - Shneiderman, Ben A1 - Shmueli,G. A1 - Jank,W. KW - data driven forecasting method KW - data visualisation KW - Data visualization KW - Economic forecasting KW - forecasting preview interface KW - Graphical user interfaces KW - historical time series dataset KW - Laboratories KW - new stock offerings KW - partial time series KW - pattern matching KW - pattern matching search KW - Predictive models KW - river plot interface KW - Rivers KW - similarity-based forecasting KW - Smoothing methods KW - Technological innovation KW - Testing KW - time series KW - time series forecasting KW - Weather forecasting AB - Time-series forecasting has a large number of applications. Users with a partial time series for auctions, new stock offerings, or industrial processes desire estimates of the future behavior. We present a data driven forecasting method and interface called similarity-based forecasting (SBF). A pattern matching search in an historical time series dataset produces a subset of curves similar to the partial time series. The forecast is displayed graphically as a river plot showing statistical information about the SBF subset. A forecasting preview interface allows users to interactively explore alternative pattern matching parameters and see multiple forecasts simultaneously. User testing with 8 users demonstrated advantages and led to improvements. JA - Information Visualization, 2007. IV '07. 11th International Conference PB - IEEE SN - 0-7695-2900-3 M3 - 10.1109/IV.2007.101 ER - TY - JOUR T1 - A simple entropy-based algorithm for planar point location JF - ACM Transactions on Algorithms (TALG) Y1 - 2007 A1 - Arya,Sunil A1 - Malamatos,Theocharis A1 - Mount, Dave KW - Entropy KW - expected-case complexity KW - Point location KW - polygonal subdivision KW - randomized algorithms KW - trapezoidal maps AB - Given a planar polygonal subdivision S, point location involves preprocessing this subdivision into a data structure so that given any query point q, the cell of the subdivision containing q can be determined efficiently. Suppose that for each cell z in the subdivision, the probability pz that a query point lies within this cell is also given. The goal is to design the data structure to minimize the average search time. This problem has been considered before, but existing data structures are all quite complicated. It has long been known that the entropy H of the probability distribution is the dominant term in the lower bound on the average-case search time. In this article, we show that a very simple modification of a well-known randomized incremental algorithm can be applied to produce a data structure of expected linear size that can answer point-location queries in O(H) average time. We also present empirical evidence for the practical efficiency of this approach. VL - 3 SN - 1549-6325 UR - http://doi.acm.org/10.1145/1240233.1240240 CP - 2 M3 - 10.1145/1240233.1240240 ER - TY - JOUR T1 - Something that is interesting is interesting then: Using text minig and visualizations to aid interpreting repetition in Gertrude Stein’s The Making of Americans JF - Proceedings of the Digital Humanities Conference Y1 - 2007 A1 - Clement,T. A1 - Don,A. A1 - Plaisant, Catherine A1 - Auvil,L. A1 - Pape,G. A1 - Goren,V. ER - TY - JOUR T1 - Story creation from heterogeneous data sources JF - Multimedia Tools and Applications Y1 - 2007 A1 - Fayzullin,M. A1 - V.S. Subrahmanian A1 - Albanese, M. A1 - Cesarano,C. A1 - Picariello, A. AB - There are numerous applications where there is a need to rapidly infer a story about a given subject from a given set of potentially heterogeneous data sources. In this paper, we formally define a story to be a set of facts about a given subject that satisfies a “story length” constraint. An optimal story is a story that maximizes the value of an objective function measuring the goodness of a story. We present algorithms to extract stories from text and other data sources. We also develop an algorithm to compute an optimal story, as well as three heuristic algorithms to rapidly compute a suboptimal story. We run experiments to show that constructing stories can be efficiently performed and that the stories constructed by these heuristic algorithms are high quality stories. We have built a prototype STORY system based on our model—we briefly describe the prototype as well as one application in this paper. VL - 33 CP - 3 M3 - 10.1007/s11042-007-0100-4 ER - TY - CONF T1 - Symmetric Objects are Hardly Ambiguous T2 - Computer Vision and Pattern Recognition, 2007. CVPR '07. IEEE Conference on Y1 - 2007 A1 - Aggarwal,G. A1 - Biswas,S. A1 - Chellapa, Rama KW - algorithm;symmetric KW - bilaterally KW - images;image KW - Lambertian KW - MATCHING KW - matching; KW - objects KW - objects;illumination-invariant KW - objects;symmetric KW - symmetric AB - Given any two images taken under different illumination conditions, there always exist a physically realizable object which is consistent with both the images even if the lighting in each scene is constrained to be a known point light source at infinity. In this paper, we show that images are much less ambiguous for the class of bilaterally symmetric Lambertian objects. In fact, the set of such objects can be partitioned into equivalence classes such that it is always possible to distinguish between two objects belonging to different equivalence classes using just one image per object. The conditions required for two objects to belong to the same equivalence class are very restrictive, thereby leading to the conclusion that images of symmetric objects are hardly ambiguous. The observation leads to an illumination-invariant matching algorithm to compare images of bilaterally symmetric Lambertian objects. Experiments on real data are performed to show the implications of the theoretical result even when the symmetry and Lambertian assumptions are not strictly satisfied. JA - Computer Vision and Pattern Recognition, 2007. CVPR '07. IEEE Conference on M3 - 10.1109/CVPR.2007.383289 ER - TY - CONF T1 - Toward domain-neutral human-level metacognition T2 - AAAI Spring Symposium on Logical Formalizations of Commonsense Reasoning Y1 - 2007 A1 - Anderson,M. L A1 - Schmill,M. A1 - Oates,T. A1 - Perlis, Don A1 - Josyula,D. A1 - Wright,D. A1 - Wilson,S. JA - AAAI Spring Symposium on Logical Formalizations of Commonsense Reasoning ER - TY - JOUR T1 - Towards the development of a virtual environment-based training system for mechanical assembly operations JF - Virtual Reality Y1 - 2007 A1 - Brough,John A1 - Schwartz,Maxim A1 - Gupta, Satyandra K. A1 - Anand,Davinder A1 - Kavetsky,Robert A1 - Pettersen,Ralph KW - Computer science AB - In this paper, we discuss the development of Virtual Training Studio (VTS), a virtual environment-based training system that allows training supervisors to create training instructions and allows trainees to learn assembly operations in a virtual environment. Our system is mainly focused on the cognitive side of training so that trainees can learn to recognize parts, remember assembly sequences, and correctly orient the parts during assembly operations. Our system enables users to train using the following three training modes: (1) Interactive Simulation, (2) 3D Animation, and (3) Video. Implementing these training modes required us to develop several new system features. This paper presents an overview of the VTS system and describes a few main features of the system. We also report user test results that show how people train using our system. The user test results indicate that the system is able to support a wide variety of training preferences and works well to support training for assembly operations. VL - 11 SN - 1359-4338 UR - http://www.springerlink.com/content/g7760422m13l83x1/abstract/ CP - 4 M3 - 10.1007/s10055-007-0076-4 ER - TY - CONF T1 - T-rex: A domain-independent system for automated cultural information extraction T2 - Proceedings of the First International Conference on Computational Cultural Dynamics (ICCCD 2007) Y1 - 2007 A1 - Albanese, M. A1 - V.S. Subrahmanian AB - RDF (Resource Description Framework) is a web standarddefined by the World Wide Web Consortium. In RDF, we can define schemas of interest. For example, we can define a schema about tribes on the Pakistan-Afghanistan borderland, or a schema about violent events. An RDF instance is a set of facts that are compatible with the schema. The principal contribution of this paper is the development of a scalable system called T-REX (short for “The RDF EXtractor”) that allows us to extract instances associated with a user-specified schema, independently of the domain about which we wish to extract data. Using T-REX, we have successfully extracted information about various aspects of about 20 tribes living in the Pakistan-Afghanistan border. Moreover, we have used T-REX to successfully extract occurrences of violent events from a set of 80 news sites in approximately 50 countries. T-REX scales well – it has processed approximately 45,000 web pages per day for the last 6 months. JA - Proceedings of the First International Conference on Computational Cultural Dynamics (ICCCD 2007) ER - TY - JOUR T1 - Understanding the Semantics of the Genetic Algorithm in Dynamic Environments JF - Applications of Evolutionary Computing Y1 - 2007 A1 - Alharbi,A. A1 - Rand, William A1 - Riolo,R AB - Researchers examining genetic algorithms (GAs) in applied settings rarely have access to anything other than fitness values of the best individuals to observe the behavior of the GA. In particular, researchers do not know what schemata are present in the population. Even when researchers look beyond best fitness values, they concentrate on either performance related measures like average fitness and robustness, or low-level descriptions like bit-level diversity measures. To understand the behavior of the GA on dynamic problems, it would be useful to track what is occurring on the “semantic” level of schemata. Thus in this paper we examine the evolving “content” in terms of schemata, as the GA solves dynamic problems. This allows us to better understand the behavior of the GA in dynamic environments. We finish by summarizing this knowledge and speculate about future work to address some of the new problems that we discovered during these experiments. M3 - 10.1007/978-3-540-71805-5_72 ER - TY - CONF T1 - Using paraphrases for parameter tuning in statistical machine translation T2 - Proceedings of the Second Workshop on Statistical Machine Translation Y1 - 2007 A1 - Madnani,Nitin A1 - Ayan,Necip Fazil A1 - Resnik, Philip A1 - Dorr, Bonnie J AB - Most state-of-the-art statistical machine translation systems use log-linear models, which are defined in terms of hypothesis features and weights for those features. It is standard to tune the feature weights in order to maximize a translation quality metric, using held-out test sentences and their corresponding reference translations. However, obtaining reference translations is expensive. In this paper, we introduce a new full-sentence paraphrase technique, based on English-to-English decoding with an MT system, and we demonstrate that the resulting paraphrases can be used to drastically reduce the number of human reference translations needed for parameter tuning, without a significant decrease in translation quality. JA - Proceedings of the Second Workshop on Statistical Machine Translation T3 - StatMT '07 PB - Association for Computational Linguistics CY - Stroudsburg, PA, USA UR - http://dl.acm.org/citation.cfm?id=1626355.1626371 ER - TY - CONF T1 - Using paraphrases for parameter tuning in statistical machine translation T2 - Proceedings of the Second Workshop on Statistical Machine Translation Y1 - 2007 A1 - Madnani,N. A1 - Ayan,N.F. A1 - Resnik, Philip A1 - Dorr, Bonnie J JA - Proceedings of the Second Workshop on Statistical Machine Translation ER - TY - CONF T1 - Using virtual demonstrations for creating multi-media training instructions Y1 - 2007 A1 - Schwartz,M. A1 - Gupta,S.K. A1 - Anand,D. K. A1 - Brough,J. E. A1 - Kavetsky,R. AB - Often generating training instructions for virtual environments is a long and tedious process. In thispaper, we discuss the development of a virtual environment (VE) instruction generating tool called Virtual Author which is the main component of the Virtual Training Studio (VTS). VTS is a virtual environment-based training system that provides instructors with a tool to create training instructions and allows trainees to learn assembly operations in a personal virtual environment. The Virtual Author tool is designed to allow an instructor to perform virtual demonstrations using CAD models in the virtual environment in order to quickly generate VE-based training instructions for use in VTS. This paper describes the algorithms used to carry out motion smoothening of instructor’s actions, automated text instruction generation based on part and assembly motions, and extraction of alignment constraints from 3D CAD models to support instruction generation. We also present examples to illustrate how the use of the Virtual Author tool leads to a significant reduction in the training instruction generation time. UR - http://www.cadanda.com/CAD_4_1-4__11.PDF ER - TY - JOUR T1 - Viable but nonculturable Vibrio cholerae O1 in biofilms in the aquatic environment and their role in cholera transmission JF - Proceedings of the National Academy of Sciences Y1 - 2007 A1 - Alam,M. A1 - Sultana,M. A1 - Nair,G. B. A1 - Siddique,A. K. A1 - Hasan,N. A. A1 - Sack,R. B. A1 - Sack,D. A. A1 - Ahmed,K. U. A1 - Sadique,A. A1 - Watanabe,H. A1 - Rita R Colwell AB - Vibrio cholerae persists in aquatic environments predominantly in a nonculturable state. In this study coccoid, nonculturable V. cholerae O1 in biofilms maintained for 495 days in Mathbaria, Bangladesh, pond water became culturable upon animal passage. Culturability, biofilm formation, and the wbe, ctxA, and rstR2 genes were monitored by culture, direct fluorescent antibody (DFA), and multiplex PCR. DFA counts were not possible after formation of biofilm. Furthermore, wbe, but not ctxA, were amplifiable, even after incubation for 54 and 68 days at room temperature (≈25°C) and 4°C, respectively, when no growth was detectable. Slower biofilm formation and extended culturability were observed for cultures incubated at 4°C, compared with ≈25°C, suggesting biofilm production to be temperature dependent and linked to loss of culturability. Small colonies appearing after incubation in microcosms for 54 and 68 days at 25°C and 4°C, respectively, were wbe positive and ctxA and rstR2 negative, indicating loss of bacteriophage CTXΦ. The coccoid V. cholerae O1 observed as free cells in microcosms incubated for 495 days could not be cultured, but biofilms in the same microcosms yielded culturable cells. It is concluded that biofilms can act as a reservoir for V. cholerae O1 between epidemics because of its long-term viability in biofilms. In contrast to biofilms produced in Mathbaria pond water, V. cholerae O1 in biofilms present in cholera stools and incubated under identical conditions as the Mathbaria pond water biofilms could not be cultured after 2 months, indicating that those V. cholerae cells freshly discharged into the environment are significantly less robust than cells adapted to environmental conditions.Bangladesh bacteriophage CTXΦ DFA multiplex-PCR ctxA VL - 104 SN - 0027-8424, 1091-6490 UR - http://www.pnas.org/content/104/45/17801 CP - 45 M3 - 10.1073/pnas.0705599104 ER - TY - CONF T1 - Video Biometrics T2 - Image Analysis and Processing, 2007. ICIAP 2007. 14th International Conference on Y1 - 2007 A1 - Chellapa, Rama A1 - Aggarwal,G. KW - (access KW - analysis;video KW - biometrics;biometrics KW - control);face KW - dynamics;ofbiometric KW - images;surveillance KW - inherent KW - MOTION KW - processing; KW - recognition;image KW - recognition;still KW - scenarios;unconstrained KW - scenarios;video KW - signal AB - A strong requirement to come up with secure and user- friendly ways to authenticate and identify people, to safeguard their rights and interests, has probably been the main guiding force behind biometrics research. Though a vast amount of research has been done to recognize humans based on still images, the problem is still far from solved for unconstrained scenarios. This has led to an increased interest in using video for the task of biometric recognition. Not only does video provide more information, but also is more suitable for recognizing humans in general surveillance scenarios. Other than the multitude of still frames, video makes it possible to characterize biometrics based on inherent dynamics like gait which is not possible with still images. In this paper, we describe several recent algorithms to illustrate the usefulness of videos to identify humans. A brief discussion on remaining challenges is also included. JA - Image Analysis and Processing, 2007. ICIAP 2007. 14th International Conference on M3 - 10.1109/ICIAP.2007.4362805 ER - TY - JOUR T1 - View-invariant modeling and recognition of human actions using grammars JF - Dynamical Vision Y1 - 2007 A1 - Ogale, A. A1 - Karapurkar, A. A1 - Aloimonos, J. ER - TY - CONF T1 - Accident or intention: That is the question (in the noisy iterated prisoner’s dilemma) Y1 - 2006 A1 - Au,T. C A1 - Nau, Dana S. AB - This paper focuses on the Noisy Iterated Prisoner’sDilemma, a version of the Iterated Prisoner’s Dilemma (IPD) in which there is a nonzero probability that a “co- operate” action will accidentally be changed into a “defect” action and vice versa. Tit-For-Tat and other strategies that do quite well in the ordinary (non-noisy) IPD can do quite badly in the Noisy IPD. This paper presents a technique called symbolic noise de- tection, for detecting whether anomalies in player’s behavior are deliberate or accidental. The key idea is to construct a model of the other agent’s behavior, and watch for any de- viation from this model. If the other agent’s next action is inconsistent with this model, the inconsistency can be due either to noise or to a genuine change in their behavior; and we can often distinguish between two cases by waiting to see whether this inconsistency persists in next few moves. We entered several different versions of our strategy in the 2005 Iterated Prisoner’s Dilemma competition, in Cat- egory 2 (noisy environments). Out of the 165 contestants in this category, our programs consistently ranked among top ten. The best of our programs ranked third, and it was beaten only by two “master-slave strategy” programs that each had a large number of “slave” programs feeding points to them. UR - http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.120.7640&rep=rep1&type=pdf ER - TY - CONF T1 - Achieving anonymity via clustering T2 - Proceedings of the twenty-fifth ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems Y1 - 2006 A1 - Aggarwal,Gagan A1 - Feder,Tomás A1 - Kenthapadi,Krishnaram A1 - Khuller, Samir A1 - Panigrahy,Rina A1 - Thomas,Dilys A1 - Zhu,An KW - anonymity KW - Approximation algorithms KW - clustering KW - privacy AB - Publishing data for analysis from a table containing personal records, while maintaining individual privacy, is a problem of increasing importance today. The traditional approach of de-identifying records is to remove identifying fields such as social security number, name etc. However, recent research has shown that a large fraction of the US population can be identified using non-key attributes (called quasi-identifiers) such as date of birth, gender, and zip code [15]. Sweeney [16] proposed the k-anonymity model for privacy where non-key attributes that leak information are suppressed or generalized so that, for every record in the modified table, there are at least k−1 other records having exactly the same values for quasi-identifiers. We propose a new method for anonymizing data records, where quasi-identifiers of data records are first clustered and then cluster centers are published. To ensure privacy of the data records, we impose the constraint that each cluster must contain no fewer than a pre-specified number of data records. This technique is more general since we have a much larger choice for cluster centers than k-Anonymity. In many cases, it lets us release a lot more information without compromising privacy. We also provide constant-factor approximation algorithms to come up with such a clustering. This is the first set of algorithms for the anonymization problem where the performance is independent of the anonymity parameter k. We further observe that a few outlier points can significantly increase the cost of anonymization. Hence, we extend our algorithms to allow an ε fraction of points to remain unclustered, i.e., deleted from the anonymized publication. Thus, by not releasing a small fraction of the database records, we can ensure that the data published for analysis has less distortion and hence is more useful. Our approximation algorithms for new clustering objectives are of independent interest and could be applicable in other clustering scenarios as well. JA - Proceedings of the twenty-fifth ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems T3 - PODS '06 PB - ACM CY - New York, NY, USA SN - 1-59593-318-2 UR - http://doi.acm.org/10.1145/1142351.1142374 M3 - 10.1145/1142351.1142374 ER - TY - CONF T1 - Applying flow-sensitive CQUAL to verify MINIX authorization check placement T2 - Proceedings of the 2006 workshop on Programming languages and analysis for security Y1 - 2006 A1 - Fraser,Timothy A1 - Petroni,Jr. A1 - Arbaugh, William A. KW - access controls KW - cqual KW - minix AB - We present the first use of flow-sensitive CQUAL to verify the placement of operating system authorization checks. Our analysis of MINIX 3 system servers and discovery of a non-exploitable Time-Of-Check/Time-Of-Use bug demonstrate the effectiveness of flow sensitive CQUAL and its advantage over earlier flow-insensitive versions. We also identify and suggest alternatives to current CQUAL usability features that encourage analysts to make omissions that cause the otherwise sound tool to produce false-negative results. JA - Proceedings of the 2006 workshop on Programming languages and analysis for security T3 - PLAS '06 PB - ACM CY - Ottawa, Ontario, Canada SN - 1-59593-374-3 M3 - 10.1145/1134744.1134747 ER - TY - JOUR T1 - An architecture for adaptive intrusion-tolerant applications JF - Software: Practice and Experience Y1 - 2006 A1 - Pal,Partha A1 - Rubel,Paul A1 - Atighetchi,Michael A1 - Webber,Franklin A1 - Sanders,William H. A1 - Seri,Mouna A1 - Ramasamy,HariGovind A1 - Lyons,James A1 - Courtney,Tod A1 - Agbaria,Adnan A1 - Michel Cukier A1 - Gossett,Jeanna A1 - Keidar,Idit KW - adaptive defense KW - adaptive middleware KW - Byzantine fault tolerance KW - intrusion tolerance KW - redundancy KW - survivability architecture AB - Applications that are part of a mission-critical information system need to maintain a usable level of key services through ongoing cyber-attacks. In addition to the well-publicized denial of service (DoS) attacks, these networked and distributed applications are increasingly threatened by sophisticated attacks that attempt to corrupt system components and violate service integrity. While various approaches have been explored to deal with DoS attacks, corruption-inducing attacks remain largely unaddressed. We have developed a collection of mechanisms based on redundancy, Byzantine fault tolerance, and adaptive middleware that help distributed, object-based applications tolerate corruption-inducing attacks. In this paper, we present the ITUA architecture, which integrates these mechanisms in a framework for auto-adaptive intrusion-tolerant systems, and we describe our experience in using the technology to defend a critical application that is part of a larger avionics system as an example. We also motivate the adaptive responses that are key to intrusion tolerance, and explain the use of the ITUA architecture to support them in an architectural framework. Copyright © 2006 John Wiley & Sons, Ltd. VL - 36 SN - 1097-024X UR - http://onlinelibrary.wiley.com/doi/10.1002/spe.747/abstract CP - 11-12 M3 - 10.1002/spe.747 ER - TY - CONF T1 - An architecture for specification-based detection of semantic integrity violations in kernel dynamic data T2 - Proceedings of the 15th conference on USENIX Security Symposium Y1 - 2006 A1 - Petroni Jr,N. L A1 - Fraser,T. A1 - Walters,A. A A1 - Arbaugh, William A. JA - Proceedings of the 15th conference on USENIX Security Symposium ER - TY - JOUR T1 - A bootstrapping model for directional wireless networks JF - Communications Letters, IEEE Y1 - 2006 A1 - Milner,S. A1 - Llorca,J. A1 - Anibha,A. A1 - Vishkin, Uzi KW - (mathematics); KW - algorithm;resource KW - algorithm;spanning KW - bootstrapping KW - bottom-up KW - discovery KW - model;directional KW - network;distributed KW - networks;trees KW - protocols;protocols;radio KW - tree;synchronization KW - wireless AB - Initially configuring or bootstrapping a connected topology in directional wireless networks is a challenging problem, especially when nodes only have local connectivity information and a limited number of transceivers. This paper presents a scalable bootstrapping model which integrates: 1) a distributed bottom-up algorithm that constructs a spanning tree with degree at most one larger than the optimal 2) a resource discovery algorithm for efficient dissemination of local connectivity information, and 3) synchronization protocols to guarantee the efficient emergence of overall network connectivity from local interactions. We investigate the feasibility and scalability of the proposed model. Results are presented for different network systems, with varying size and signaling data rates. VL - 10 SN - 1089-7798 CP - 12 M3 - 10.1109/LCOMM.2006.060808 ER - TY - RPRT T1 - Challenges and Opportunities in Internet Data Mining Y1 - 2006 A1 - Andersen,D.G. A1 - Feamster, Nick AB - Internet measurement data provides the foundation for the operation and planning of the networks that comprise the Internet, and is a necessary component in research for analysis, simulation, and emulation. Despite its critical role, however, the management of this data—from collection and transmission to storage and its use within applications—remains primarily ad hoc, using techniques created and re-created by each corporation or researcher that uses the data. This paper examines several of the challenges faced when attempting to collect and archive large volumes of network measurement data, and outlines an architecture for an Internet data repository—the datapository designed to create a framework for collaboratively addressing these challenges. PB - Parallel Data Laboratory, Carnegie Mellon University VL - CMU-PDL-06-102 ER - TY - JOUR T1 - A client-driven approach for channel management in wireless LANs JF - IEEE Infocom Y1 - 2006 A1 - Mishra,A. A1 - Brik,V. A1 - Banerjee,S. A1 - Srinivasan, Aravind A1 - Arbaugh, William A. AB - We propose an efficient client-based approach for channel man-agement (channel assignment and load balancing) in 802.11-based WLANs that lead to better usage of the wireless spectrum. This approach is based on a “conflict set coloring” formulation that jointly performs load balancing along with channel assignment. Such a formulation has a number of advantages. First, it explicitly captures interference effects at clients. Next, it intrinsically ex- poses opportunities for better channel re-use. Finally, algorithms based on this formulation do not depend on specific physical RF models and hence can be applied efficiently to a wide-range of in- building as well as outdoor scenarios. We have performed extensive packet-level simulations and mea- surements on a deployed wireless testbed of 70 APs to validate the performance of our proposed algorithms. We show that in addi- tion to single network scenarios, the conflict set coloring formu- lation is well suited for channel assignment where multiple wire- less networks share and contend for spectrum in the same physical space. Our results over a wide range of both simulated topologies and in-building testbed experiments indicate that our approach improves application level performance at the clients by upto three times (and atleast 50%) in comparison to current best-known tech- niques. VL - 6 ER - TY - JOUR T1 - Client-driven channel management for wireless LANs JF - SIGMOBILE Mob. Comput. Commun. Rev. Y1 - 2006 A1 - Mishra,Arunesh A1 - Brik,Vladimir A1 - Banerjee,Suman A1 - Srinivasan, Aravind A1 - Arbaugh, William A. AB - With the explosive growth in the density of 802.11 access points (APs) in the form of hotspots and public/home access networks, coordinating the shared use of spectrum has become an important problem. The irregular coverage topologies present in WLANs due to the vagaries of the indoor RF environment make the channel assignment algorithms in cellular networks inapplicable [1, 2]. VL - 10 SN - 1559-1662 UR - http://doi.acm.org/10.1145/1215976.1215981 CP - 4 M3 - 10.1145/1215976.1215981 ER - TY - JOUR T1 - The cost of compatible refinement of simplex decomposition trees JF - Proceedings of the 15th International Meshing Roundtable Y1 - 2006 A1 - Atalay,F. A1 - Mount, Dave AB - A hierarchical simplicial mesh is a recursive decomposition of space into cells that are simplices. Such a mesh is compatible if pairs of neighboring cells meet along a single common face. Compatibility condition is important in many applications where the mesh serves as a discretization of a function. Enforcing compatibility involves refining the simplices of the mesh further, thus generates a larger mesh. We show that the size of a simplicial mesh grows by no more than a constant factor when compatibly refined. We prove a tight upper bound on the expansion factor for 2-dimensional meshes, and we sketch upper bounds for d-dimensional meshes. M3 - 10.1007/978-3-540-34958-7_4 ER - TY - CONF T1 - Deformation and viewpoint invariant color histograms T2 - British Machine Vision Conference Y1 - 2006 A1 - Domke, J. A1 - Aloimonos, J. JA - British Machine Vision Conference VL - 2 ER - TY - JOUR T1 - Density estimation using mixtures of mixtures of Gaussians JF - Computer Vision–ECCV 2006 Y1 - 2006 A1 - Abd-Almageed, Wael A1 - Davis, Larry S. AB - In this paper we present a new density estimation algorithm using mixtures of mixtures of Gaussians. The new algorithm overcomes the limitations of the popular Expectation Maximization algorithm. The paper first introduces a new model selection criterion called the Penalty-less Information Criterion, which is based on the Jensen-Shannon divergence. Mean-shift is used to automatically initialize the means and covariances of the Expectation Maximization in order to obtain better structure inference. Finally, a locally linear search is performed using the Penalty-less Information Criterion in order to infer the underlying density of the data. The validity of the algorithm is verified using real color images. ER - TY - JOUR T1 - Differential Transcriptional Response to Nonassociative and Associative Components of Classical Fear Conditioning in the Amygdala and Hippocampus JF - Learning & MemoryLearn. Mem. Y1 - 2006 A1 - Keeley,Michael B A1 - Wood,Marcelo A A1 - Isiegas,Carolina A1 - Stein,Joel A1 - Hellman,Kevin A1 - Hannenhalli, Sridhar A1 - Abel,Ted AB - Classical fear conditioning requires the recognition of conditioned stimuli (CS) and the association of the CS with an aversive stimulus. We used Affymetrix oligonucleotide microarrays to characterize changes in gene expression compared to naive mice in both the amygdala and the hippocampus 30 min after classical fear conditioning and 30 min after exposure to the CS in the absence of an aversive stimulus. We found that in the hippocampus, levels of gene regulation induced by classical fear conditioning were not significantly greater than those induced by CS alone, whereas in the amygdala, classical fear conditioning did induce significantly greater levels of gene regulation compared to the CS. Computational studies suggest that transcriptional changes in the hippocampus and amygdala are mediated by large and overlapping but distinct combinations of molecular events. Our results demonstrate that an increase in gene regulation in the amygdala was partially correlated to associative learning and partially correlated to nonassociative components of the task, while gene regulation in the hippocampus was correlated to nonassociative components of classical fear conditioning, including configural learning. VL - 13 SN - 1072-0502, 1549-5485 UR - http://learnmem.cshlp.org/content/13/2/135 CP - 2 M3 - 10.1101/lm.86906 ER - TY - CONF T1 - Distance join queries on spatial networks T2 - Proceedings of the 14th annual ACM international symposium on Advances in geographic information systems Y1 - 2006 A1 - Sankaranarayanan,Jagan A1 - Alborzi,Houman A1 - Samet, Hanan KW - location-based services KW - path coherence KW - Query processing KW - SILC framework KW - Spatial databases KW - spatial networks AB - The result of a distance join operation on two sets of objects R, S on a spatial network G is a set P of object pairs pq, p É R, q É S such that the distance of an object pair pq is the shortest distance from p to q in G. Several variations to the distance join operation such as UnOrdered, Incremental, topk, Semi-Join impose additional constraints on the distance between the object pairs in P, the ordering of object pairs in P, and on the cardinality of P. A distance join algorithm on spatial networks is proposed that works in conjunction with the SILC framework, which is a new approach to query processing on spatial networks. Experimental results demonstrate up to an order of magnitude speed up when compared with a prominent existing technique. JA - Proceedings of the 14th annual ACM international symposium on Advances in geographic information systems T3 - GIS '06 PB - ACM CY - New York, NY, USA SN - 1-59593-529-0 UR - http://doi.acm.org/10.1145/1183471.1183506 M3 - 10.1145/1183471.1183506 ER - TY - CONF T1 - Edge Suppression by Gradient Field Transformation Using Cross-Projection Tensors T2 - Computer Vision and Pattern Recognition, 2006 IEEE Computer Society Conference on Y1 - 2006 A1 - Agrawal,A. A1 - Raskar, R. A1 - Chellapa, Rama AB - We propose a new technique for edge-suppressing operations on images. We introduce cross projection tensors to achieve affine transformations of gradient fields. We use these tensors, for example, to remove edges in one image based on the edge-information in a second image. Traditionally, edge suppression is achieved by setting image gradients to zero based on thresholds. A common application is in the Retinex problem, where the illumination map is recovered by suppressing the reflectance edges, assuming it is slowly varying. We present a class of problems where edge-suppression can be a useful tool. These problems involve analyzing images of the same scene under variable illumination. Instead of resetting gradients, the key idea in our approach is to derive local tensors using one image and to transform the gradient field of another image using them. Reconstructed image from the modified gradient field shows suppressed edges or textures at the corresponding locations. All operations are local and our approach does not require any global analysis. We demonstrate the algorithm in the context of several applications such as (a) recovering the foreground layer under varying illumination, (b) estimating intrinsic images in non-Lambertian scenes, (c) removing shadows from color images and obtaining the illumination map, and (d) removing glass reflections. JA - Computer Vision and Pattern Recognition, 2006 IEEE Computer Society Conference on VL - 2 M3 - 10.1109/CVPR.2006.106 ER - TY - JOUR T1 - Effect of transport at ambient temperature on detection and isolation of Vibrio cholerae from environmental samples JF - Applied and environmental microbiology Y1 - 2006 A1 - Alam,M. A1 - Sadique,A. A1 - Bhuiyan,N. A. A1 - Nair,G. B. A1 - Siddique,A. K. A1 - Sack,D. A. A1 - Ahsan,S. A1 - Huq,A. A1 - Sack,R. B. A1 - Rita R Colwell A1 - others AB - It has long been assumed that prolonged holding of environmental samples at the ambient air temperature prior to bacteriological analysis is detrimental to isolation and detection of Vibrio cholerae, the causative agent of pandemic cholera. The present study was aimed at understanding the effect of transporting environmental samples at the ambient air temperature on isolation and enumeration of V. cholerae. For water and plankton samples held at ambient temperatures ranging from 31°C to 35°C for 20 h, the total counts did not increase significantly but the number of culturable V. cholerae increased significantly compared to samples processed within 1 h of collection, as measured by culture, acridine orange direct count, direct fluorescent-antibody-direct viable count (DFA-DVC), and multiplex PCR analyses. For total coliform counts, total bacterial counts, and DFA-DVC counts, the numbers did not increase significantly, but the culturable plate counts for V. cholerae increased significantly after samples were held at the ambient temperature during transport to the laboratory for analysis. An increase in the recovery of V. cholerae O1 and improved detection of V. cholerae O1 rfb and ctxA also occurred when samples were enriched after they were kept for 20 h at the ambient temperature during transport. Improved detection and isolation of toxigenic V. cholerae from freshwater ecosystems can be achieved by holding samples at the ambient temperature, an observation that has significant implications for tracking this pathogen in diverse aquatic environments. VL - 72 CP - 3 ER - TY - CONF T1 - Enabling Query Processing on Spatial Networks T2 - Data Engineering, 2006. ICDE '06. Proceedings of the 22nd International Conference on Y1 - 2006 A1 - Sankaranarayanan,J. A1 - Alborzi,H. A1 - Samet, Hanan AB - A system that enables real time query processing on large spatial networks is demonstrated. The system provides functionality for processing a wide range of spatial queries such as nearest neighbor searches and spatial joins on spatial networks of sufficiently large sizes. JA - Data Engineering, 2006. ICDE '06. Proceedings of the 22nd International Conference on M3 - 10.1109/ICDE.2006.60 ER - TY - JOUR T1 - Enhancing reinforcement learning with metacognitive monitoring and control for improved perturbation tolerance JF - Journal of Experimental and Theoretical Artificial Intelligence Y1 - 2006 A1 - Anderson,M. L A1 - Oates,T. A1 - Chong,W. A1 - Perlis, Don VL - 18 CP - 3 ER - TY - JOUR T1 - Experiments to understand HPC time to development JF - CTWatch Quarterly Y1 - 2006 A1 - Hochstein, Lorin A1 - Nakamura,Taiga A1 - Basili, Victor R. A1 - Asgari, Sima A1 - Zelkowitz, Marvin V A1 - Hollingsworth, Jeffrey K A1 - Shull, Forrest A1 - Carver,Jeffrey A1 - Voelp,Martin A1 - Zazworka, Nico A1 - Johnson,Philip KW - hackystat KW - HPC KW - publications-journals AB - In order to understand how high performance computing (HPC) programs are developed, a series of experiments, using students in graduate level HPC classes, have been conducted at many universities in the US. In this paper we discuss the general process of conducting those experiments, give some of the early results of those experiments, and describe a web-based process we are developing that will allow us to run additional experiments at other universities and laboratories that will be easier to conduct and generate results that more accurately reflect the process of building HPC programs. UR - http://csdl.ics.hawaii.edu/techreports/06-08/06-08.pdf ER - TY - JOUR T1 - Exploiting independence for branch operations in Bayesian learning of C&RTs JF - Probabilistic, Logical and Relational Learning-Towards a Synthesis Y1 - 2006 A1 - Angelopoulos,N. A1 - Cussens,J. A1 - De Raedt,L. A1 - Dietterich,T. A1 - Getoor, Lise A1 - Muggleton,S. H AB - In this paper we extend a methodology for Bayesian learning via MCMC, with the ability to grow arbitrarily long branches in C&RT models. We are able to do so by exploiting independence in the model construction process. The ability to grow branches rather than single nodes has been noted as desirable in the literature. The most singular feature of the underline methodology used here in comparison to other approaches is the coupling of the prior and the proposal. The main contribution of this paper is to show how taking advantage of independence in the coupled process, can allow branch growing and swapping for proposal models. ER - TY - JOUR T1 - Exploring auction databases through interactive visualization JF - Decision Support Systems Y1 - 2006 A1 - Shmueli,Galit A1 - Jank,Wolfgang A1 - Aris,Aleks A1 - Plaisant, Catherine A1 - Shneiderman, Ben KW - Auction dynamics KW - Bid history KW - Online auctions KW - time series KW - user interface AB - We introduce AuctionExplorer, a suite of tools for exploring databases of online auctions. The suite combines tools for collecting, processing, and interactively exploring auction attributes (e.g., seller rating), and the bid history (price evolution represented as a time series). Part of AuctionExplorer's power comes from its coupling of the two information structures, thereby allowing exploration of relationships between them. Exploration can be directed by hypothesis testing or exploratory data analysis. We propose a process for visual data analysis and illustrate AuctionExplorer's operations with a dataset of eBay auctions. Insights may improve seller, bidder, auction house, and other vendors' understanding of the market, thereby assisting their decision making process. VL - 42 SN - 0167-9236 UR - http://www.sciencedirect.com/science/article/pii/S0167923606000042 CP - 3 M3 - 10.1016/j.dss.2006.01.001 ER - TY - CONF T1 - Exploring erotics in Emily Dickinson's correspondence with text mining and visual interfaces T2 - Proceedings of the 6th ACM/IEEE-CS joint conference on Digital libraries Y1 - 2006 A1 - Plaisant, Catherine A1 - Rose,James A1 - Yu,Bei A1 - Auvil,Loretta A1 - Kirschenbaum,Matthew G. A1 - Smith,Martha Nell A1 - Clement,Tanya A1 - Lord,Greg KW - case studies KW - humanities KW - literary criticism KW - text mining KW - user interface KW - Visualization AB - This paper describes a system to support humanities scholars in their interpretation of literary work. It presents a user interface and web architecture that integrates text mining, a graphical user interface and visualization, while attempting to remain easy to use by non specialists. Users can interactively read and rate documents found in a digital libraries collection, prepare training sets, review results of classification algorithms and explore possible indicators and explanations. Initial evaluation steps suggest that there is a rationale for "provocational" text mining in literary interpretation. JA - Proceedings of the 6th ACM/IEEE-CS joint conference on Digital libraries T3 - JCDL '06 PB - ACM CY - New York, NY, USA SN - 1-59593-354-9 UR - http://doi.acm.org/10.1145/1141753.1141781 M3 - 10.1145/1141753.1141781 ER - TY - CONF T1 - Exploring the limits of single-iteration clarification dialogs T2 - Proceedings of the 29th annual international ACM SIGIR conference on Research and development in information retrieval Y1 - 2006 A1 - Jimmy Lin A1 - Wu,Philip A1 - Demner-Fushman,Dina A1 - Abels,Eileen KW - interactive retrieval KW - intermediated search KW - TREC HARD AB - Single-iteration clarification dialogs, as implemented in the TREC HARD track, represent an attempt to introduce interaction into ad hoc retrieval, while preserving the many benefits of large-scale evaluations. Although previous experiments have not conclusively demonstrated performance gains resulting from such interactions, it is unclear whether these findings speak to the nature of clarification dialogs, or simply the limitations of current systems. To probe the limits of such interactions, we employed a human intermediary to formulate clarification questions and exploit user responses. In addition to establishing a plausible upper bound on performance, we were also able to induce an "ontology of clarifications" to characterize human behavior. This ontology, in turn, serves as the input to a regression model that attempts to determine which types of clarification questions are most helpful. Our work can serve to inform the design of interactive systems that initiate user dialogs. JA - Proceedings of the 29th annual international ACM SIGIR conference on Research and development in information retrieval T3 - SIGIR '06 PB - ACM CY - New York, NY, USA SN - 1-59593-369-7 UR - http://doi.acm.org/10.1145/1148170.1148251 M3 - 10.1145/1148170.1148251 ER - TY - JOUR T1 - First Steps Toward an Electronic Field Guide for Plants JF - Taxon Y1 - 2006 A1 - Haibin,Gaurav Agarwal A1 - Agarwal,Gaurav A1 - Ling,Haibin A1 - Jacobs, David W. A1 - Shirdhonkar,Sameer A1 - Kress,W. John A1 - Russell,Rusty A1 - Belhumeur,Peter A1 - Dixit,An A1 - Feiner,Steve A1 - Mahajan,Dhruv A1 - Sunkavalli,Kalyan A1 - Ramamoorthi,Ravi A1 - White,Sean AB - this paper, we will describe our progress towards building a digital collection of the Smithsonian's type specimens, developing recognition algorithms that can match an image of a leaf to the species of plant from which it comes, and designing user interfaces for interacting with an electronic field guide. To start, we are developing a prototype electronic field guide for the flora of Plummers Island, a small, well-studied island in the Potomac River. This prototype system contains multiple images for each of about 130 species of plants on the island, and should soon grow to cover all 200+ species currently recorded (Shetler et al., 2005). Images of full specimens are available, as well as images of isolated leaves of each species. A zoomable user interface allows a user to browse these images, zooming in on ones of interest. Visual recognition algorithms assist a botanist in locating the specimens that are most relevant to identify the species of a plant. The system currently runs on a small hand-held computer. We will describe the components of this prototype, and also describe some of the future challenges we anticipate if we are to provide botanists in the field with all the resources that are now currently available in the world's museums and herbaria. Type Specimen Digital Collection The first challenge in producing our electronic field guide is to create a digital collection covering all of the Smithsonian's 85,000 vascular plant type specimens. For each type specimen, the database should eventually include systematically acquired high-resolution digital images of the specimen, textual descriptions, links to decision trees, images of live plants, and 3D models. Figure 1: On the left, our set-up at the Smithsonian for digitally photographing type specimens. On the... VL - 55 ER - TY - JOUR T1 - Flow-insensitive type qualifiers JF - ACM Transactions on Programming Languages and Systems (TOPLAS) Y1 - 2006 A1 - Foster, Jeffrey S. A1 - Johnson,R. A1 - Kodumal,J. A1 - Aiken,A. VL - 28 CP - 6 ER - TY - CONF T1 - Going beyond AER: an extensive analysis of word alignments and their impact on MT T2 - Proceedings of the 21st International Conference on Computational Linguistics and the 44th annual meeting of the Association for Computational Linguistics Y1 - 2006 A1 - Ayan,Necip Fazil A1 - Dorr, Bonnie J AB - This paper presents an extensive evaluation of five different alignments and investigates their impact on the corresponding MT system output. We introduce new measures for intrinsic evaluations and examine the distribution of phrases and untranslated words during decoding to identify which characteristics of different alignments affect translation. We show that precision-oriented alignments yield better MT output (translating more words and using longer phrases) than recall-oriented alignments. JA - Proceedings of the 21st International Conference on Computational Linguistics and the 44th annual meeting of the Association for Computational Linguistics T3 - ACL-44 PB - Association for Computational Linguistics CY - Stroudsburg, PA, USA UR - http://dx.doi.org/10.3115/1220175.1220177 M3 - 10.3115/1220175.1220177 ER - TY - JOUR T1 - Human activity language: Grounding concepts with a linguistic framework JF - Semantic Multimedia Y1 - 2006 A1 - Guerra-Filho,G. A1 - Aloimonos, J. ER - TY - CONF T1 - On the importance of idempotence T2 - Proceedings of the thirty-eighth annual ACM symposium on Theory of computing Y1 - 2006 A1 - Arya,Sunil A1 - Malamatos,Theocharis A1 - Mount, Dave KW - Approximation algorithms KW - Idempotence KW - Range searching AB - Range searching is among the most fundamental problems in computational geometry. An n-element point set in Rd is given along with an assignment of weights to these points from some commutative semigroup. Subject to a fixed space of possible range shapes, the problem is to preprocess the points so that the total semigroup sum of the points lying within a given query range η can be determined quickly. In the approximate version of the problem we assume that η is bounded, and we are given an approximation parameter ε > 0. We are to determine the semigroup sum of all the points contained within η and may additionally include any of the points lying within distance ε • diam(η) of η's boundar.In this paper we contrast the complexity of range searching based on semigroup properties. A semigroup (S,+) is idempotent if x + x = x for all x ∈ S, and it is integral if for all k ≥ 2, the k-fold sum x + ... + x is not equal to x. For example, (R, min) and (0,1, ∨) are both idempotent, and (N, +) is integral. To date, all upper and lower bounds hold irrespective of the semigroup. We show that semigroup properties do indeed make a difference for both exact and approximate range searching, and in the case of approximate range searching the differences are dramatic.First, we consider exact halfspace range searching. The assumption that the semigroup is integral allows us to improve the best lower bounds in the semigroup arithmetic model. For example, assuming O(n) storage in the plane and ignoring polylog factors, we provide an Ω*(n2/5) lower bound for integral semigroups, improving upon the best lower bound of Ω*(n1/3), thus closing the gap with the O(n1/2) upper bound.We also consider approximate range searching for Euclidean ball ranges. We present lower bounds and nearly matching upper bounds for idempotent semigroups. We also present lower bounds for range searching for integral semigroups, which nearly match existing upper bounds. These bounds show that the advantages afforded by idempotency can result in major improvements. In particular, assuming roughly linear space, the exponent in the ε-dependencies is smaller by a factor of nearly 1/2. All our results are presented in terms of space-time tradeoffs, and our lower and upper bounds match closely throughout the entire spectrum.To our knowledge, our results provide the first proof that semigroup properties affect the computational complexity of range searching in the semigroup arithmetic model. These are the first lower bound results for any approximate geometric retrieval problems. The existence of nearly matching upper bounds, throughout the range of space-time tradeoffs, suggests that we are close to resolving the computational complexity of both idempotent and integral approximate spherical range searching in the semigroup arithmetic model. JA - Proceedings of the thirty-eighth annual ACM symposium on Theory of computing T3 - STOC '06 PB - ACM CY - New York, NY, USA SN - 1-59593-134-1 UR - http://doi.acm.org/10.1145/1132516.1132598 M3 - 10.1145/1132516.1132598 ER - TY - JOUR T1 - The incompleteness of planning with volatile external information JF - FRONTIERS IN ARTIFICIAL IN℡LIGENCE AND APPLICATIONS Y1 - 2006 A1 - Au,T. A1 - Nau, Dana S. AB - In many real-world planning environments, someof the information about the world is both external (the planner must request it from external information sources) and volatile (it changes before the planning process completes). In such en- vironments, a planner faces two challenges: how to generate plans despite changes in the external information during plan- ning, and how to guarantee that a plan returned by the plan- ner will remain valid for some period of time after the plan- ning ends. Previous works on planning with volatile informa- tion have addressed the first challenge, but not the second one. This paper provides a general model for planning with volatile external information in which the planner offers a guar- antee of how long the solution will remain valid after it is re- turned, and an incompleteness theorem showing that there is no planner that can succeed in solving all solvable planning prob- lems in which there is volatile external information. VL - 141 UR - http://www.cs.umd.edu/~nau/papers/au2006incompleteness.pdf ER - TY - CONF T1 - Integrated Motion Detection and Tracking for Visual Surveillance T2 - Computer Vision Systems, 2006 ICVS '06. IEEE International Conference on Y1 - 2006 A1 - Abdelkader, M.F. A1 - Chellapa, Rama A1 - Qinfen Zheng A1 - Chan, A.L. AB - Visual surveillance systems have gained a lot of interest in the last few years. In this paper, we present a visual surveillance system that is based on the integration of motion detection and visual tracking to achieve better performance. Motion detection is achieved using an algorithm that combines temporal variance with background modeling methods. The tracking algorithm combines motion and appearance information into an appearance model and uses a particle filter framework for tracking the object in subsequent frames. The systems was tested on a large ground-truthed data set containing hundreds of color and FLIR image sequences. A performance evaluation for the system was performed and the average evaluation results are reported in this paper. JA - Computer Vision Systems, 2006 ICVS '06. IEEE International Conference on M3 - 10.1109/ICVS.2006.35 ER - TY - CONF T1 - Integration of visual and inertial information for egomotion: a stochastic approach T2 - Proceedings 2006 IEEE International Conference on Robotics and Automation, 2006. ICRA 2006 Y1 - 2006 A1 - Domke, J. A1 - Aloimonos, J. KW - Computer vision KW - data mining KW - Distributed computing KW - egomotion estimation KW - Gabor filters KW - Gravity KW - inertial information KW - inertial sensor KW - Laboratories KW - Motion estimation KW - Noise measurement KW - Probability distribution KW - probability distributions KW - Rotation measurement KW - stochastic approach KW - Stochastic processes KW - visual information AB - We present a probabilistic framework for visual correspondence, inertial measurements and egomotion. First, we describe a simple method based on Gabor filters to produce correspondence probability distributions. Next, we generate a noise model for inertial measurements. Probability distributions over the motions are then computed directly from the correspondence distributions and the inertial measurements. We investigate combining the inertial and visual information for a single distribution over the motions. We find that with smaller amounts of correspondence information, fusion of the visual data with the inertial sensor results in much better egomotion estimation. This is essentially because inertial measurements decrease the "translation-rotation" ambiguity. However, when more correspondence information is used, this ambiguity is reduced to such a degree that the inertial measurements provide negligible improvement in accuracy. This suggests that inertial and visual information are more closely integrated in a compositional sense JA - Proceedings 2006 IEEE International Conference on Robotics and Automation, 2006. ICRA 2006 PB - IEEE SN - 0-7803-9505-0 M3 - 10.1109/ROBOT.2006.1642007 ER - TY - CONF T1 - Invariant Geometric Representation of 3D Point Clouds for Registration and Matching T2 - Image Processing, 2006 IEEE International Conference on Y1 - 2006 A1 - Biswas,S. A1 - Aggarwal,G. A1 - Chellapa, Rama KW - 3D KW - cloud;computer KW - function KW - geometric KW - graphics;geophysical KW - graphics;image KW - Interpolation KW - matching;image KW - point KW - processing;image KW - reconstruction;image KW - registration;image KW - registration;implicit KW - representation;interpolation; KW - representation;variational KW - signal KW - technique;clouds;computer KW - value;invariant AB - Though implicit representations of surfaces have often been used for various computer graphics tasks like modeling and morphing of objects, it has rarely been used for registration and matching of 3D point clouds. Unlike in graphics, where the goal is precise reconstruction, we use isosurfaces to derive a smooth and approximate representation of the underlying point cloud which helps in generalization. Implicit surfaces are generated using a variational interpolation technique. Implicit function values on a set of concentric spheres around the 3D point cloud of object are used as features for matching. Geometric-invariance is achieved by decomposing implicit values based feature set into various spherical harmonics. The decomposition provides a compact representation of 3D point clouds while achieving rotation invariance JA - Image Processing, 2006 IEEE International Conference on M3 - 10.1109/ICIP.2006.312542 ER - TY - CHAP T1 - Lower Bounds on the Deterministic and Quantum Communication Complexities of Hamming-Distance Problems T2 - Algorithms and ComputationAlgorithms and Computation Y1 - 2006 A1 - Ambainis,Andris A1 - Gasarch,William A1 - Srinivasan, Aravind A1 - Utis,Andrey ED - Asano,Tetsuo AB - A sub-area of discrepancy theory that has received much attention in computer science re-cently, is that of explicit constructions of low-discrepancy point sets for various types of rectangle families in high dimension. This research has led to interesting applications in error-control cod- ing, distributed protocols, Web document filtering, derandomization, and other areas. We give a short survey of this area here. JA - Algorithms and ComputationAlgorithms and Computation T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 4288 SN - 978-3-540-49694-6 UR - http://dx.doi.org/10.1007/11940128_63 ER - TY - CONF T1 - Maintaining cooperation in noisy environments Y1 - 2006 A1 - Au,T. C A1 - Nau, Dana S. AB - To prevent or alleviate conflicts in multi-agent environ- ments, it is important to distinguish between situations where another agent has misbehaved intentionally and situations where the misbehavior was accidental. One situation where this problem arises is the Noisy Iterated Prisoner’s Dilemma, a version of the Iterated Prisoner’s Dilemma (IPD) in which there is a nonzero probability that a “cooperate” action will accidentally be changed into a “defect” action and vice versa. Tit-For-Tat and other strategies that do quite well in the ordi- nary (non-noisy) IPD can do quite badly in the Noisy IPD.This paper presents a technique called symbolic noise detec- tion, for detecting whether anomalies in player’s behavior are deliberate or accidental. This idea to use player’s determin- istic behavior to tell whether an action has been affected by noise. We also present DBS, an algorithm that uses symbolic noise detection in the Noisy IPD. DBS constructs a model of the other agent’s deterministic behavior, and watches for any deviation from this model. If the other agent’s next ac- tion is inconsistent with this model, the inconsistency can be due either to noise or to a genuine change in their behavior; and DBS can often distinguish between two cases by waiting to see whether this inconsistency persists in next few moves. This technique is effective because many IPD players often have clear deterministic patterns of behavior. We entered several different implementations of DBS in the 2005 Iterated Prisoner’s Dilemma competition, in Category 2 (noisy environments). Out of the 165 contestants in this cate- gory, most of DBS implementations ranked among top ten. The best one ranked third, and it was beaten only by two “master-and-slaves strategy” programs that each had a large number of “slave” programs feeding points to them. VL - 21 UR - https://www.aaai.org/Papers/AAAI/2006/AAAI06-250.pdf ER - TY - CONF T1 - A maximum entropy approach to combining word alignments T2 - Proceedings of the main conference on Human Language Technology Conference of the North American Chapter of the Association of Computational Linguistics Y1 - 2006 A1 - Ayan,Necip Fazil A1 - Dorr, Bonnie J AB - This paper presents a new approach to combining outputs of existing word alignment systems. Each alignment link is represented with a set of feature functions extracted from linguistic features and input alignments. These features are used as the basis of alignment decisions made by a maximum entropy approach. The learning method has been evaluated on three language pairs, yielding significant improvements over input alignments and three heuristic combination methods. The impact of word alignment on MT quality is investigated, using a phrase-based MT system. JA - Proceedings of the main conference on Human Language Technology Conference of the North American Chapter of the Association of Computational Linguistics T3 - HLT-NAACL '06 PB - Association for Computational Linguistics CY - Stroudsburg, PA, USA UR - http://dx.doi.org/10.3115/1220835.1220848 M3 - 10.3115/1220835.1220848 ER - TY - JOUR T1 - Measuring human movement for biomechanical applications using markerless motion capture JF - Proceedings of SPIE Y1 - 2006 A1 - Mündermann, L. A1 - Corazza, S. A1 - Chaudhari, A.M. A1 - Andriacchi, T.P. A1 - Sundaresan, A. A1 - Chellapa, Rama AB - Modern biomechanical and clinical applications require the accurate capture of normal and pathological humanmovement without the artifacts associated with standard marker-based motion capture techniques such as soft tissue artifacts and the risk of artificial stimulus of taped-on or strapped-on markers. In this study, the need for new markerless human motion capture methods is discussed in view of biomechanical applications. Three different approaches for estimating human movement from multiple image sequences were explored. The first two approaches tracked a 3D articulated model in 3D representations constructed from the image sequences, while the third approach tracked a 3D articulated model in multiple 2D image planes. The three methods are systematically evaluated and results for real data are presented. The role of choosing appropriate technical equipment and algorithms for accurate markerless motion capture is critical. The implementation of this new methodology offers the promise for simple, time-efficient, and potentially more meaningful assessments of human movement in research and clinical practice. VL - 6056 ER - TY - JOUR T1 - The metacognitive loop I: Enhancing reinforcement learning with metacognitive monitoring and control for improved perturbation tolerance JF - Journal of Experimental & Theoretical Artificial Intelligence Y1 - 2006 A1 - Anderson,M. L A1 - Oates,T. A1 - Chong,W. A1 - Perlis, Don VL - 18 CP - 3 ER - TY - CONF T1 - Model-based OpenMP implementation of a 3D facial pose tracking system T2 - 2006 International Conference on Parallel Processing Workshops, 2006. ICPP 2006 Workshops Y1 - 2006 A1 - Saha,S. A1 - Chung-Ching Shen A1 - Chia-Jui Hsu A1 - Aggarwal,G. A1 - Veeraraghavan,A. A1 - Sussman, Alan A1 - Bhattacharyya, Shuvra S. KW - 3D facial pose tracking system KW - application modeling KW - application program interfaces KW - application scheduling KW - coarse-grain dataflow graphs KW - Concurrent computing KW - data flow graphs KW - Educational institutions KW - face recognition KW - IMAGE PROCESSING KW - image processing applications KW - Inference algorithms KW - Message passing KW - OpenMP platform KW - parallel implementation KW - PARALLEL PROCESSING KW - parallel programming KW - Particle tracking KW - Processor scheduling KW - SHAPE KW - shared memory systems KW - shared-memory systems KW - Solid modeling KW - tracking AB - Most image processing applications are characterized by computation-intensive operations, and high memory and performance requirements. Parallelized implementation on shared-memory systems offer an attractive solution to this class of applications. However, we cannot thoroughly exploit the advantages of such architectures without proper modeling and analysis of the application. In this paper, we describe our implementation of a 3D facial pose tracking system using the OpenMP platform. Our implementation is based on a design methodology that uses coarse-grain dataflow graphs to model and schedule the application. We present our modeling approach, details of the implementation that we derived based on this modeling approach, and associated performance results. The parallelized implementation achieves significant speedup, and meets or exceeds the target frame rate under various configurations JA - 2006 International Conference on Parallel Processing Workshops, 2006. ICPP 2006 Workshops PB - IEEE SN - 0-7695-2637-3 M3 - 10.1109/ICPPW.2006.55 ER - TY - JOUR T1 - Molecular Characterization of Serine-, Alanine-, and Proline-Rich Proteins of Trypanosoma cruzi and Their Possible Role in Host Cell Infection JF - Infect. Immun. Y1 - 2006 A1 - Baida,Renata C. P. A1 - Santos,Marcia R. M. A1 - Carmo,Mirian S. A1 - Yoshida,Nobuko A1 - Ferreira,Danielle A1 - Ferreira,Alice Teixeira A1 - El Sayed,Najib M. A1 - Andersson,Bjorn A1 - da Silveira,Jose Franco AB - We previously reported the isolation of a novel protein gene family, termed SAP (serine-, alanine-, and proline-rich protein), from Trypanosoma cruzi. Aided by the availability of the completed genome sequence of T. cruzi, we have now identified 39 full-length sequences of SAP, six pseudogenes and four partial genes. SAPs share a central domain of about 55 amino acids and can be divided into four groups based on their amino (N)- and carboxy (C)-terminal sequences. Some SAPs have conserved N- and C-terminal domains encoding a signal peptide and a glycosylphosphatidylinositol anchor addition site, respectively. Analysis of the expression of SAPs in metacyclic trypomastigotes by two-dimensional electrophoresis and immunoblotting revealed that they are likely to be posttranslationally modified in vivo. We have also demonstrated that some SAPs are shed into the extracellular medium. The recombinant SAP exhibited an adhesive capacity toward mammalian cells, where binding was dose dependent and saturable, indicating a possible ligand-receptor interaction. SAP triggered the host cell Ca2+ response required for parasite internalization. A cell invasion assay performed in the presence of SAP showed inhibition of internalization of the metacyclic forms of the CL strain. Taken together, these results show that SAP is involved in the invasion of mammalian cells by metacyclic trypomastigotes, and they confirm the hypothesis that infective trypomastigotes exploit an arsenal of surface glycoproteins and shed proteins to induce signaling events required for their internalization. VL - 74 UR - http://iai.asm.org/cgi/content/abstract/74/3/1537 CP - 3 M3 -

10.1128/IAI.74.3.1537-1546.2006

ER - TY - CONF T1 - Multiple range query optimization with distributed cache indexing T2 - Proceedings of the 2006 ACM/IEEE conference on Supercomputing Y1 - 2006 A1 - Nam,B. A1 - Andrade,H. A1 - Sussman, Alan JA - Proceedings of the 2006 ACM/IEEE conference on Supercomputing ER - TY - JOUR T1 - Multi-view Reconstruction of Static and Dynamic Scenes JF - Handbook of Mathematical Models in Computer Vision Y1 - 2006 A1 - Agrawal,M. A1 - Mittal,A. A1 - Davis, Larry S. AB - We explore the reconstruction of a three-dimensional scene from multiple images captured from far away viewpoints (wide-baseline camera arrangement). Such an arrangement is required for complex scenes where the visibility flora any one viewpoint is not sufficient to adequately reconstruct the entire scene. Also, such an arrangement reduces the error in triangulation of the features, thereby improving the accuracy of reconstruction. Our emphasis is on algorithms that recover a volumetric model of the scene from calibrated cameras by explicitly modeling and detecting occlusions. We present a brief overview of the state of the art in such methods for multi-view reconstruction. In particular, algorithms based on a probabilistic framework have become quite popular and produce very accurate models. Several such probabilistic volume reconstruction methods will be described. For the dynamic parts of the scene, where an online reconstruction is needed, simpler methods are required. An important case of such scenes is that of walking people in a surveillance scenario. For this case, we present fast online algorithms that recover approximate shape and appearance models and 3D trajectories of people as they walk in the scene. Finally, we address the problem of optimal placement of cameras in order to acquire the best possible image data for the reconstruction of a given scene according to the particular task specification. ER - TY - JOUR T1 - Network Visualization by Semantic Substrates JF - IEEE Transactions on Visualization and Computer Graphics Y1 - 2006 A1 - Shneiderman, Ben A1 - Aris,A. KW - Automatic control KW - data visualisation KW - Data visualization KW - Displays KW - Filters KW - Graphical user interfaces KW - Information Visualization KW - information visualization designers KW - Law KW - legal citations KW - Legal factors KW - legal precedent data KW - network visualization KW - NVSS 1.0 KW - scalability KW - semantic substrate KW - Terminology KW - Tunneling KW - user-defined semantic substrates AB - Networks have remained a challenge for information visualization designers because of the complex issues of node and link layout coupled with the rich set of tasks that users present. This paper offers a strategy based on two principles: (1) layouts are based on user-defined semantic substrates, which are non-overlapping regions in which node placement is based on node attributes, (2) users interactively adjust sliders to control link visibility to limit clutter and thus ensure comprehensibility of source and destination. Scalability is further facilitated by user control of which nodes are visible. We illustrate our semantic substrates approach as implemented in NVSS 1.0 with legal precedent data for up to 1122 court cases in three regions with 7645 legal citations VL - 12 SN - 1077-2626 CP - 5 M3 - 10.1109/TVCG.2006.166 ER - TY - JOUR T1 - Nuclear Envelope Dystrophies Show a Transcriptional Fingerprint Suggesting Disruption of Rb–MyoD Pathways in Muscle Regeneration JF - BrainBrain Y1 - 2006 A1 - Bakay,Marina A1 - Wang,Zuyi A1 - Melcon,Gisela A1 - Schiltz,Louis A1 - Xuan,Jianhua A1 - Zhao,Po A1 - Sartorelli,Vittorio A1 - Seo,Jinwook A1 - Pegoraro,Elena A1 - Angelini,Corrado A1 - Shneiderman, Ben A1 - Escolar,Diana A1 - Chen,Yi-Wen A1 - Winokur,Sara T A1 - Pachman,Lauren M A1 - Fan,Chenguang A1 - Mandler,Raul A1 - Nevo,Yoram A1 - Gordon,Erynn A1 - Zhu,Yitan A1 - Dong,Yibin A1 - Wang,Yue A1 - Hoffman,Eric P KW - EDMD = Emery–Dreifuss muscular dystrophy KW - emerin KW - Emery-Dreifuss muscular dystrophy KW - FSHD = fascioscapulohumeral muscular dystrophy KW - IDG = individual discriminatory genes KW - JDG = jointly discriminatory genes KW - lamin A/C KW - LGMD = limb-girdle muscular dystrophy KW - LOO = leave-one-out KW - RT–PCR = reverse transcription–polymerase chain reaction; VISDA = Visual and Statistical Data Analyzer KW - Skeletal muscle KW - wFC = weighted Fisher criterion AB - Mutations of lamin A/C (LMNA) cause a wide range of human disorders, including progeria, lipodystrophy, neuropathies and autosomal dominant Emery–Dreifuss muscular dystrophy (EDMD). EDMD is also caused by X-linked recessive loss-of-function mutations of emerin, another component of the inner nuclear lamina that directly interacts with LMNA. One model for disease pathogenesis of LMNA and emerin mutations is cell-specific perturbations of the mRNA transcriptome in terminally differentiated cells. To test this model, we studied 125 human muscle biopsies from 13 diagnostic groups (125 U133A, 125 U133B microarrays), including EDMD patients with LMNA and emerin mutations. A Visual and Statistical Data Analyzer (VISDA) algorithm was used to statistically model cluster hierarchy, resulting in a tree of phenotypic classifications. Validations of the diagnostic tree included permutations of U133A and U133B arrays, and use of two probe set algorithms (MAS5.0 and MBEI). This showed that the two nuclear envelope defects (EDMD LMNA, EDMD emerin) were highly related disorders and were also related to fascioscapulohumeral muscular dystrophy (FSHD). FSHD has recently been hypothesized to involve abnormal interactions of chromatin with the nuclear envelope. To identify disease-specific transcripts for EDMD, we applied a leave-one-out (LOO) cross-validation approach using LMNA patient muscle as a test data set, with reverse transcription–polymerase chain reaction (RT–PCR) validations in both LMNA and emerin patient muscle. A high proportion of top-ranked and validated transcripts were components of the same transcriptional regulatory pathway involving Rb1 and MyoD during muscle regeneration (CRI-1, CREBBP, Nap1L1, ECREBBP/p300), where each was specifically upregulated in EDMD. Using a muscle regeneration time series (27 time points) we develop a transcriptional model for downstream consequences of LMNA and emerin mutations. We propose that key interactions between the nuclear envelope and Rb and MyoD fail in EDMD at the point of myoblast exit from the cell cycle, leading to poorly coordinated phosphorylation and acetylation steps. Our data is consistent with mutations of nuclear lamina components leading to destabilization of the transcriptome in differentiated cells. VL - 129 SN - 0006-8950, 1460-2156 UR - http://brain.oxfordjournals.org/content/129/4/996 CP - 4 M3 - 10.1093/brain/awl023 ER - TY - JOUR T1 - Open problems in relational data clustering JF - Proceedings of the ICML Workshop on Open Problems in Stastistical Relational Learning Y1 - 2006 A1 - Anthony,A. A1 - desJardins, Marie AB - Data clustering is the task of detecting pat-terns in a set of data. Most algorithms take non-relational data as input and are sometimes unable to find significant patterns. Many data sets can include relational infor- mation, as well as independent object at- tributes. We believe that clustering with re- lational data will help find significant pat- terns where non-relational algorithms fail. This paper discusses two open problems in relational data clustering: clustering hetero- geneous data, and relation selection or ex- traction. Potential methods for addressing the problems are presented. ER - TY - RPRT T1 - OverDoSe: A generic DDoS protection service using an overlay network Y1 - 2006 A1 - Elaine Shi A1 - Stoica,I. A1 - Andersen,D.G. A1 - Perrig, A. AB - We present the design and implementation of OverDoSe, an overlay network offering generic DDoS protection for targeted sites. OverDoSe clients and servers are isolated at the IP level. Overlay nodes route packets between a client and a server, and regulate traffic according to the server’s instructions. Through the use of light-weight security primitives, OverDoSe achieves resilience against compromised overlay nodes with a minimal performance overhead. OverDoSe can be deployed by a single ISP who wishes to offer DDoS protection as a value-adding service to its customers. PB - School of Computer Science, Carnegie Mellon University SN - CMU-CS-06-114 UR - http://repository.cmu.edu/cgi/viewcontent.cgi?article=1073&context=compsci M3 - Technical Report ER - TY - CONF T1 - Partially overlapped channels not considered harmful T2 - Proceedings of the joint international conference on Measurement and modeling of computer systems Y1 - 2006 A1 - Mishra,A. A1 - Shrivastava,V. A1 - Banerjee,S. A1 - Arbaugh, William A. JA - Proceedings of the joint international conference on Measurement and modeling of computer systems ER - TY - JOUR T1 - The priority curve algorithm for video summarization JF - Information Systems Y1 - 2006 A1 - Albanese, M. A1 - Fayzullin,M. A1 - Picariello, A. A1 - V.S. Subrahmanian KW - Content based retrieval KW - Video databases KW - Video summarization AB - In this paper, we introduce the concept of a priority curve associated with a video. We then provide an algorithm that can use the priority curve to create a summary (of a desired length) of any video. The summary thus created exhibits nice continuity properties and also avoids repetition. We have implemented the priority curve algorithm (PriCA) and compared it with other summarization algorithms in the literature with respect to both performance and the output quality. The quality of summaries was evaluated by a group of 200 students in Naples, Italy, who watched soccer videos. We show that PriCA is faster than existing algorithms and also produces better quality summaries. We also briefly describe a soccer video summarization system we have built on using the PriCA architecture and various (classical) image processing algorithms. VL - 31 SN - 0306-4379 UR - http://www.sciencedirect.com/science/article/pii/S0306437905001250 CP - 7 M3 - 10.1016/j.is.2005.12.003 ER - TY - CONF T1 - A probabilistic notion of correspondence and the epipolar constraint T2 - Proceedings of the Third International Symposium on 3D Data Processing, Visualization, and Transmission (3DPVT'06) Y1 - 2006 A1 - Domke, J. A1 - Aloimonos, J. JA - Proceedings of the Third International Symposium on 3D Data Processing, Visualization, and Transmission (3DPVT'06) ER - TY - JOUR T1 - Provable algorithms for parallel generalized sweep scheduling JF - Journal of Parallel and Distributed Computing Y1 - 2006 A1 - Anil Kumar,V. S A1 - Marathe,M. V A1 - Parthasarathy,S. A1 - Srinivasan, Aravind A1 - Zust,S. VL - 66 CP - 6 ER - TY - BOOK T1 - Real-Time Distributed Algorithms for Visual and Battlefield Reasoning Y1 - 2006 A1 - Davis, Larry S. A1 - Basili, Victor R. A1 - V.S. Subrahmanian A1 - Reggia, James A. A1 - Aloimonos, J. AB - Information is key to the success of the next generation battlefield. There is a critical need to determine, in real-time, what the enemy is doing, and to interpret that information in the context of past related events. In this project we examined two aspects of this issue: development of a high-level task definition language for tasking a network of sensors to carry out given objectives, and interpreting recounted events so that past related scenarios could be automatically identified from a case database. PB - MARYLAND UNIV COLLEGE PARK OFFICE OF RESEARCH ADMINISTRATION AND ADVANCEMENT ER - TY - CONF T1 - Real-Time Human Detection, Tracking, and Verification in Uncontrolled Camera Motion Environments T2 - Computer Vision Systems, 2006 ICVS '06. IEEE International Conference on Y1 - 2006 A1 - Hussein,M. A1 - Abd-Almageed, Wael A1 - Yang Ran A1 - Davis, Larry S. AB - In environments where a camera is installed on a freely moving platform, e.g. a vehicle or a robot, object detection and tracking becomes much more difficult. In this paper, we presents a real time system for human detection, tracking, and verification in such challenging environments. To deliver a robust performance, the system integrates several computer vision algorithms to perform its function: a human detection algorithm, an object tracking algorithm, and a motion analysis algorithm. To utilize the available computing resources to the maximum possible extent, each of the system components is designed to work in a separate thread that communicates with the other threads through shared data structures. The focus of this paper is more on the implementation issues than on the algorithmic issues of the system. Object oriented design was adopted to abstract algorithmic details away from the system structure. JA - Computer Vision Systems, 2006 ICVS '06. IEEE International Conference on M3 - 10.1109/ICVS.2006.52 ER - TY - JOUR T1 - Robust ego-motion estimation and 3-D model refinement using surface parallax JF - Image Processing, IEEE Transactions on Y1 - 2006 A1 - Agrawal,A. A1 - Chellapa, Rama KW - 3D model refinement KW - algorithms KW - Artificial intelligence KW - Automated;Subtraction Technique; KW - Computer-Assisted;Imaging KW - constant parallax model KW - depth based parallax model KW - digital elevation map KW - epipolar field KW - Image Enhancement KW - Image Interpretation KW - iterative algorithm KW - iterative methods KW - Motion estimation KW - robust ego-motion estimation KW - smooth parallax field KW - surface parallax KW - Three-Dimensional;Information Storage and Retrieval;Pattern Recognition AB - We present an iterative algorithm for robustly estimating the ego-motion and refining and updating a coarse depth map using parametric surface parallax models and brightness derivatives extracted from an image pair. Given a coarse depth map acquired by a range-finder or extracted from a digital elevation map (DEM), ego-motion is estimated by combining a global ego-motion constraint and a local brightness constancy constraint. Using the estimated camera motion and the available depth estimate, motion of the three-dimensional (3-D) points is compensated. We utilize the fact that the resulting surface parallax field is an epipolar field, and knowing its direction from the previous motion estimates, estimate its magnitude and use it to refine the depth map estimate. The parallax magnitude is estimated using a constant parallax model (CPM) which assumes a smooth parallax field and a depth based parallax model (DBPM), which models the parallax magnitude using the given depth map. We obtain confidence measures for determining the accuracy of the estimated depth values which are used to remove regions with potentially incorrect depth estimates for robustly estimating ego-motion in subsequent iterations. Experimental results using both synthetic and real data (both indoor and outdoor sequences) illustrate the effectiveness of the proposed algorithm. VL - 15 SN - 1057-7149 CP - 5 M3 - 10.1109/TIP.2005.864167 ER - TY - JOUR T1 - Seasonal Cholera Caused by Vibrio Cholerae Serogroups O1 and O139 in the Coastal Aquatic Environment of Bangladesh JF - Applied and Environmental MicrobiologyAppl. Environ. Microbiol. Y1 - 2006 A1 - Alam,Munirul A1 - Hasan,Nur A. A1 - Sadique,Abdus A1 - Bhuiyan,N. A. A1 - Ahmed,Kabir U. A1 - Nusrin,Suraia A1 - Nair,G. Balakrish A1 - Siddique,A. K. A1 - Sack,R. Bradley A1 - Sack,David A. A1 - Huq,Anwar A1 - Rita R Colwell AB - Since Vibrio cholerae O139 first appeared in 1992, both O1 El Tor and O139 have been recognized as the epidemic serogroups, although their geographic distribution, endemicity, and reservoir are not fully understood. To address this lack of information, a study of the epidemiology and ecology of V. cholerae O1 and O139 was carried out in two coastal areas, Bakerganj and Mathbaria, Bangladesh, where cholera occurs seasonally. The results of a biweekly clinical study (January 2004 to May 2005), employing culture methods, and of an ecological study (monthly in Bakerganj and biweekly in Mathbaria from March 2004 to May 2005), employing direct and enrichment culture, colony blot hybridization, and direct fluorescent-antibody methods, showed that cholera is endemic in both Bakerganj and Mathbaria and that V. cholerae O1, O139, and non-O1/non-O139 are autochthonous to the aquatic environment. Although V. cholerae O1 and O139 were isolated from both areas, most noteworthy was the isolation of V. cholerae O139 in March, July, and September 2004 in Mathbaria, where seasonal cholera was clinically linked only to V. cholerae O1. In Mathbaria, V. cholerae O139 emerged as the sole cause of a significant outbreak of cholera in March 2005. V. cholerae O1 reemerged clinically in April 2005 and established dominance over V. cholerae O139, continuing to cause cholera in Mathbaria. In conclusion, the epidemic potential and coastal aquatic reservoir for V. cholerae O139 have been demonstrated. Based on the results of this study, the coastal ecosystem of the Bay of Bengal is concluded to be a significant reservoir for the epidemic serogroups of V. cholerae. VL - 72 SN - 0099-2240, 1098-5336 UR - http://aem.asm.org/content/72/6/4096 CP - 6 M3 - 10.1128/AEM.00066-06 ER - TY - CONF T1 - A sensory grammar for inferring behaviors in sensor networks T2 - Proceedings of the 5th international conference on Information processing in sensor networks Y1 - 2006 A1 - Lymberopoulos, Dimitrios A1 - Ogale, Abhijit S. A1 - Savvides, Andreas A1 - Aloimonos, J. KW - algorithms KW - behavior identification KW - human activity KW - human factors KW - pcfg KW - real-time and embedded systems KW - sensor grammars KW - sensor networks AB - The ability of a sensor network to parse out observable activities into a set of distinguishable actions is a powerful feature that can potentially enable many applications of sensor networks to everyday life situations. In this paper we introduce a framework that uses a hierarchy of Probabilistic Context Free Grammars (PCFGs) to perform such parsing. The power of the framework comes from the hierarchical organization of grammars that allows the use of simple local sensor measurements for reasoning about more macroscopic behaviors. Our presentation describes how to use a set of phonemes to construct grammars and how to achieve distributed operation using a messaging model. The proposed framework is flexible. It can be mapped to a network hierarchy or can be applied sequentially and across the network to infer behaviors as they unfold in space and time. We demonstrate this functionality by inferring simple motion patterns using a sequence of simple direction vectors obtained from our camera sensor network testbed. JA - Proceedings of the 5th international conference on Information processing in sensor networks T3 - IPSN '06 PB - ACM CY - Nashville, Tennessee, USA SN - 1-59593-334-4 M3 - 10.1145/1127777.1127817 ER - TY - CONF T1 - A Sensory-Motor Language for Human Activity Understanding T2 - 2006 6th IEEE-RAS International Conference on Humanoid Robots Y1 - 2006 A1 - Guerra-Filho,G. A1 - Aloimonos, J. KW - Actuators KW - associative learning KW - atomic segments KW - computational linguistics KW - Computer science KW - Computer vision KW - Educational institutions KW - grammars KW - human activity language KW - human activity understanding KW - human movement syntax KW - Humanoid robots KW - HUMANS KW - joint angles KW - kinetemes KW - kinetological system KW - Laboratories KW - learning (artificial intelligence) KW - List key index terms here KW - Morphology KW - motor information KW - No mare than 5 KW - parallel learning KW - Reproducibility of results KW - Robot kinematics KW - Robot programming KW - robot vision KW - sensory-motor language KW - sequential language learning KW - symbolic nonarbitrary representation KW - visual information AB - We have empirically discovered that the space of human actions has a linguistic framework. This is a sensory-motor space consisting of the evolution of the joint angles of the human body in movement. The space of human activity has its own phonemes, morphemes, and sentences. We present a human activity language (HAL) for symbolic non-arbitrary representation of visual and motor information. In phonology, we define atomic segments (kinetemes) that are used to compose human activity. We introduce the concept of a kinetological system and propose five basic properties for such a system: compactness, view-invariance, reproducibility, selectivity, and reconstructivity. In morphology, we extend sequential language learning to incorporate associative learning with our parallel learning approach. Parallel learning is effective in identifying the kinetemes and active joints in a particular action. In syntax, we suggest four lexical categories for our human activity language (noun, verb, adjective, and adverb). These categories are combined into sentences through syntax for human movement JA - 2006 6th IEEE-RAS International Conference on Humanoid Robots PB - IEEE SN - 1-4244-0200-X M3 - 10.1109/ICHR.2006.321365 ER - TY - JOUR T1 - Session 8A-Combinatorial Optimization and Quantum Computing-Lower Bounds on the Deterministic and Quantum Communication Complexities of Hamming-Distance Problems JF - Lecture Notes in Computer Science Y1 - 2006 A1 - Ambainis,A. A1 - Gasarch,W. A1 - Srinivasan, Aravind A1 - Utis,A. VL - 4288 ER - TY - CONF T1 - A structural approach to latency prediction T2 - Proceedings of the 6th ACM SIGCOMM conference on Internet measurement Y1 - 2006 A1 - Madhyastha,Harsha V. A1 - Anderson,Thomas A1 - Krishnamurthy,Arvind A1 - Spring, Neil A1 - Venkataramani,Arun KW - internet topology KW - latency prediction KW - route measurements AB - Several models have been recently proposed for predicting the latency of end to end Internet paths. These models treat the Internet as a black-box, ignoring its internal structure. While these models are simple, they can often fail systematically; for example, the most widely used models use metric embeddings that predict no benefit to detour routes even though half of all Internet routes can benefit from detours.In this paper, we adopt a structural approach that predicts path latency based on measurements of the Internet's routing topology, PoP connectivity, and routing policy. We find that our approach outperforms Vivaldi, the most widely used black-box model. Furthermore, unlike metric embeddings, our approach successfully predicts 65% of detour routes in the Internet. The number of measurements used in our approach is comparable with that required by black box techniques, but using traceroutes instead of pings. JA - Proceedings of the 6th ACM SIGCOMM conference on Internet measurement T3 - IMC '06 PB - ACM CY - New York, NY, USA SN - 1-59593-561-4 UR - http://doi.acm.org/10.1145/1177080.1177092 M3 - 10.1145/1177080.1177092 ER - TY - PAT T1 - System and method for locating a closest server in response to a client ... Y1 - 2006 A1 - Andrews,Matthew A1 - Hofmann,Markus A1 - Shepherd,Bruce A1 - Srinivasan, Aravind A1 - Winkler,Peter A1 - Zane,Francis ED - Lucent Technologies Inc. AB - A scalable system and method for locating a closest server in response to a client request via an interactive distribution network, such as the Internet, are provided. A closest content server is defined as having the least round trip time for responding to a client request. The system including a plurality of content servers; and a local server in communication with a plurality of clients, the local server acting as a proxy for communicating client requests from clients to a redirection server. Client network distance and load information is periodically collected at each content server in the network from clients communicating with each of the respective content servers. The redirection server periodically aggregates the network distance and load information from each content server to create client clusters from both current and previously aggregated network distance and load information. Each client cluster represents a division or partition of the total IP address space. Each... VL - 09/726,192 UR - http://www.google.com/patents?id=cE54AAAAEBAJ CP - 7020698 ER - TY - CONF T1 - Towards a sensorimotor WordNet SM: Closing the semantic gap T2 - Proc. of the International WordNet Conference (GWC) Y1 - 2006 A1 - Guerra-Filho,G. A1 - Aloimonos, J. JA - Proc. of the International WordNet Conference (GWC) ER - TY - JOUR T1 - Toxigenic Vibrio Cholerae in the Aquatic Environment of Mathbaria, Bangladesh JF - Applied and Environmental MicrobiologyAppl. Environ. Microbiol. Y1 - 2006 A1 - Alam,Munirul A1 - Sultana,Marzia A1 - Nair,G. Balakrish A1 - Sack,R. Bradley A1 - Sack,David A. A1 - Siddique,A. K. A1 - Ali,Afsar A1 - Huq,Anwar A1 - Rita R Colwell AB - Toxigenic Vibrio cholerae, rarely isolated from the aquatic environment between cholera epidemics, can be detected in what is now understood to be a dormant stage, i.e., viable but nonculturable when standard bacteriological methods are used. In the research reported here, biofilms have proved to be a source of culturable V. cholerae, even in nonepidemic periods. Biweekly environmental surveillance for V. cholerae was carried out in Mathbaria, an area of cholera endemicity adjacent to the Bay of Bengal, with the focus on V. cholerae O1 and O139 Bengal. A total of 297 samples of water, phytoplankton, and zooplankton were collected between March and December 2004, yielding eight V. cholerae O1 and four O139 Bengal isolates. A combination of culture methods, multiplex-PCR, and direct fluorescent antibody (DFA) counting revealed the Mathbaria aquatic environment to be a reservoir for V. cholerae O1 and O139 Bengal. DFA results showed significant clumping of the bacteria during the interepidemic period for cholera, and the fluorescent micrographs revealed large numbers of V. cholerae O1 in thin films of exopolysaccharides (biofilm). A similar clumping of V. cholerae O1 was also observed in samples collected from Matlab, Bangladesh, where cholera also is endemic. Thus, the results of the study provided in situ evidence for V. cholerae O1 and O139 in the aquatic environment, predominantly as viable but nonculturable cells and culturable cells in biofilm consortia. The biofilm community is concluded to be an additional reservoir of cholera bacteria in the aquatic environment between seasonal epidemics of cholera in Bangladesh. VL - 72 SN - 0099-2240, 1098-5336 UR - http://aem.asm.org/content/72/4/2849 CP - 4 M3 - 10.1128/AEM.72.4.2849-2855.2006 ER - TY - CONF T1 - Tracking Articulating Objects from Ground Vehicles using Mixtures of Mixtures T2 - Intelligent Robots and Systems, 2006 IEEE/RSJ International Conference on Y1 - 2006 A1 - Abd-Almageed, Wael A1 - Hussein,M. A1 - Davis, Larry S. KW - articulating KW - filter;unmanned KW - ground KW - information;mixtures KW - mixtures;particle KW - objects KW - of KW - operated KW - tracking;egomotion KW - vehicle;remotely KW - vehicles;robot KW - vision; AB - An algorithm for tracking articulating objects from moving camera platforms is presented. Mixtures of mixtures are used to model the appearance of the object and the background. The state of the object is tracked using a particle filter. Egomotion information are estimated and used to set the state variance of the particle filter. Results of tracking human objects from an unmanned ground vehicle are used to evaluate the tracking algorithm JA - Intelligent Robots and Systems, 2006 IEEE/RSJ International Conference on M3 - 10.1109/IROS.2006.281881 ER - TY - JOUR T1 - Understanding visuo‐motor primitives for motion synthesis and analysis JF - Computer Animation and Virtual Worlds Y1 - 2006 A1 - Guerra‐Filho,Gutemberg A1 - Aloimonos, J. KW - compression KW - motion synthesis KW - visuo‐motor primitives AB - The problem addressed in this paper concerns the representation of human movement in terms of atomic visuo-motor primitives considering both generation and perception of movement. We introduce the concept of kinetology, the phonology of human movement, and five principles on which such a system should be based: compactness, view-invariance, reproducibility, selectivity, and reconstructivity. We propose visuo-motor primitives and demonstrate their kinetological properties. Further evaluation is accomplished with experiments on compression and decompression. Our long-term goal is to demonstrate that action has a space characterized by a visuo-motor language. Copyright © 2006 John Wiley & Sons, Ltd. VL - 17 SN - 1546-427X UR - http://onlinelibrary.wiley.com/doi/10.1002/cav.124/abstract CP - 3‐4 M3 - 10.1002/cav.124 ER - TY - CHAP T1 - What Is the Range of Surface Reconstructions from a Gradient Field? T2 - Computer Vision – ECCV 2006Computer Vision – ECCV 2006 Y1 - 2006 A1 - Agrawal,Amit A1 - Raskar,Ramesh A1 - Chellapa, Rama ED - Leonardis,Aleš ED - Bischof,Horst ED - Pinz,Axel AB - We propose a generalized equation to represent a continuum of surface reconstruction solutions of a given non-integrable gradient field. We show that common approaches such as Poisson solver and Frankot-Chellappa algorithm are special cases of this generalized equation. For a N × N pixel grid, the subspace of all integrable gradient fields is of dimension N 2 – 1. Our framework can be applied to derive a range of meaningful surface reconstructions from this high dimensional space. The key observation is that the range of solutions is related to the degree of anisotropy in applying weights to the gradients in the integration process. While common approaches use isotropic weights, we show that by using a progression of spatially varying anisotropic weights, we can achieve significant improvement in reconstructions. We propose (a) α-surfaces using binary weights, where the parameter α allows trade off between smoothness and robustness, (b) M-estimators and edge preserving regularization using continuous weights and (c) Diffusion using affine transformation of gradients. We provide results on photometric stereo, compare with previous approaches and show that anisotropic treatment discounts noise while recovering salient features in reconstructions. JA - Computer Vision – ECCV 2006Computer Vision – ECCV 2006 T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 3951 SN - 978-3-540-33832-1 UR - http://dx.doi.org/10.1007/11744023_45 ER - TY - JOUR T1 - Wireless Network Security and Interworking JF - Proceedings of the IEEE Y1 - 2006 A1 - Shin,M. A1 - Ma,J. A1 - Mishra,A. A1 - Arbaugh, William A. KW - 3G mobile communication KW - 3G systems KW - Authentication KW - Bandwidth KW - Communication system security KW - computer network security KW - computer security KW - Data security KW - internetworking KW - Land mobile radio cellular systems KW - Paper technology KW - security architectures KW - security of data KW - telecommunication security KW - wireless communication KW - wireless communications KW - Wireless LAN KW - wireless network security KW - Wireless networks KW - wireless technologies KW - WLAN systems AB - A variety of wireless technologies have been standardized and commercialized, but no single technology is considered the best because of different coverage and bandwidth limitations. Thus, interworking between heterogeneous wireless networks is extremely important for ubiquitous and high-performance wireless communications. Security in interworking is a major challenge due to the vastly different security architectures used within each network. The goal of this paper is twofold. First, we provide a comprehensive discussion of security problems and current technologies in 3G and WLAN systems. Second, we provide introductory discussions about the security problems in interworking, the state-of-the-art solutions, and open problems. VL - 94 SN - 0018-9219 CP - 2 M3 - 10.1109/JPROC.2005.862322 ER - TY - CHAP T1 - 3D Facial Pose Tracking in Uncalibrated Videos T2 - Pattern Recognition and Machine IntelligencePattern Recognition and Machine Intelligence Y1 - 2005 A1 - Aggarwal,Gaurav A1 - Veeraraghavan,Ashok A1 - Chellapa, Rama ED - Pal,Sankar ED - Bandyopadhyay,Sanghamitra ED - Biswas,Sambhunath AB - This paper presents a method to recover the 3D configuration of a face in each frame of a video. The 3D configuration consists of the 3 translational parameters and the 3 orientation parameters which correspond to the yaw, pitch and roll of the face, which is important for applications like face modeling, recognition, expression analysis, etc. The approach combines the structural advantages of geometric modeling with the statistical advantages of a particle-filter based inference. The face is modeled as the curved surface of a cylinder which is free to translate and rotate arbitrarily. The geometric modeling takes care of pose and self-occlusion while the statistical modeling handles moderate occlusion and illumination variations. Experimental results on multiple datasets are provided to show the efficacy of the approach. The insensitivity of our approach to calibration parameters (focal length) is also shown. JA - Pattern Recognition and Machine IntelligencePattern Recognition and Machine Intelligence T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 3776 SN - 978-3-540-30506-4 UR - http://dx.doi.org/10.1007/11590316_81 ER - TY - CONF T1 - An algebraic approach to surface reconstruction from gradient fields T2 - Computer Vision, 2005. ICCV 2005. Tenth IEEE International Conference on Y1 - 2005 A1 - Agrawal,A. A1 - Chellapa, Rama A1 - Raskar, R. KW - algebra; KW - algebraic KW - approach; KW - Computer KW - confinement; KW - discrete KW - domain KW - error KW - field; KW - from KW - gradient KW - graph KW - image KW - integrability; KW - linear KW - local KW - methods; KW - photometric KW - reconstruction; KW - shading; KW - SHAPE KW - stereo; KW - surface KW - system; KW - theory; KW - vision; AB - Several important problems in computer vision such as shape from shading (SFS) and photometric stereo (PS) require reconstructing a surface from an estimated gradient field, which is usually non-integrable, i.e. have non-zero curl. We propose a purely algebraic approach to enforce integrability in discrete domain. We first show that enforcing integrability can be formulated as solving a single linear system Ax =b over the image. In general, this system is under-determined. We show conditions under which the system can be solved and a method to get to those conditions based on graph theory. The proposed approach is non-iterative, has the important property of local error confinement and can be applied to several problems. Results on SFS and PS demonstrate the applicability of our method. JA - Computer Vision, 2005. ICCV 2005. Tenth IEEE International Conference on VL - 1 M3 - 10.1109/ICCV.2005.31 ER - TY - CONF T1 - Alignment link projection using transformation-based learning T2 - Proceedings of the conference on Human Language Technology and Empirical Methods in Natural Language Processing Y1 - 2005 A1 - Ayan,Necip Fazil A1 - Dorr, Bonnie J A1 - Monz,Christof AB - We present a new word-alignment approach that learns errors made by existing word alignment systems and corrects them. By adapting transformation-based learning to the problem of word alignment, we project new alignment links from already existing links, using features such as POS tags. We show that our alignment link projection approach yields a significantly lower alignment error rate than that of the best performing alignment system (22.6% relative reduction on English-Spanish data and 23.2% relative reduction on English-Chinese data). JA - Proceedings of the conference on Human Language Technology and Empirical Methods in Natural Language Processing T3 - HLT '05 PB - Association for Computational Linguistics CY - Stroudsburg, PA, USA UR - http://dx.doi.org/10.3115/1220575.1220599 M3 - 10.3115/1220575.1220599 ER - TY - JOUR T1 - Applications of SHOP and SHOP2 JF - Intelligent Systems, IEEE Y1 - 2005 A1 - Nau, Dana S. A1 - Au,T.-C. A1 - Ilghami,O. A1 - Kuter,U. A1 - Wu,D. A1 - Yaman,F. A1 - Munoz-Avila,H. A1 - Murdock,J. W. KW - automated planning KW - hierarchical task network planning KW - ordered task decomposition KW - planning (artificial intelligence) KW - problem solving KW - search-control strategy KW - simple hierarchical ordered planner KW - trees (mathematics) KW - uncertainty handling AB - We design the simple hierarchical ordered planner (SHOP) and its successor, SHOP2, with two goals in mind: to investigate research issues in automated planning and to provide some simple, practical planning tools. SHOP and SHOP2 are based on a planning formalism called hierarchical task network planning. SHOP and SHOP2 use a search-control strategy called ordered task decomposition, which breaks tasks into subtasks and generates the plan's actions in the same order that the plan executor executes them. So, throughout the planning process, the planner can tell what the state of the world at each step of the plan. VL - 20 SN - 1541-1672 CP - 2 M3 - 10.1109/MIS.2005.20 ER - TY - CONF T1 - An architectural level design methodology for embedded face detection T2 - Proceedings of the 3rd IEEE/ACM/IFIP international conference on Hardware/software codesign and system synthesis Y1 - 2005 A1 - Kianzad,V. A1 - Saha,S. A1 - Schlessman,J. A1 - Aggarwal,G. A1 - Bhattacharyya, Shuvra S. A1 - Wolf,W. A1 - Chellapa, Rama KW - design space exploration KW - Face detection KW - platforms KW - reconfigurable KW - system-level models AB - Face detection and recognition research has attracted great attention in recent years. Automatic face detection has great potential in a large array of application areas, including banking and security system access control, video surveillance, and multimedia information retrieval. In this paper, we discuss an architectural level design methodology for implementation of an embedded face detection system on a reconfigurable system on chip. We present models for performance estimation and validate these models with experimental values obtained from implementing our system on an FPGA platform. This modeling approach is shown to be efficient, accurate, and intuitive for designers to work with. Using this approach, we present several design options that trade-off various architectural features. JA - Proceedings of the 3rd IEEE/ACM/IFIP international conference on Hardware/software codesign and system synthesis T3 - CODES+ISSS '05 PB - ACM CY - New York, NY, USA SN - 1-59593-161-9 UR - http://doi.acm.org/10.1145/1084834.1084872 M3 - 10.1145/1084834.1084872 ER - TY - JOUR T1 - Chromatic Induction and Perspective Distortion JF - Journal of VisionJ Vis Y1 - 2005 A1 - Aloimonos, J. A1 - Fermüller, Cornelia AB - A pattern presented by Robertson (1996), consisting of yellow and blue square waves with red squares superimposed on either the blue or yellow bands give rise to assimilation effects similar as in the White illusion. The red squares on the yellow bands appear more blue, and the red squares on the blue bands appear more yellow. Varying the position and orientation of the pattern in space changes the effect. For example, slanting the pattern or increasing the distance to the pattern in space increases the effect. But rotating the pattern by 90 degrees and slanting it, nearly eliminates the effect. These changes in color appearance can be explained as the result of averaging in receptive field of extended size.Due to perspective distortion, the area of the pattern in space mapping to an image patch changes with the position and orientation of the pattern. A computational simulation, implementing the distortion from 3D space to image space, followed by a color segmentation (k-means clustering) gave the same color distortion and segmentation as perceived. Thus the effect seems to be simple an artifact of sampling which causes averaging or smoothing with some filters. We propose the hypothesis that chromatic induction, which takes the two forms of chromatic contrast and assimilation, results, because the system samples with large fields and following in the segmentation stage attempts to compensate for the averaging effects in neighboring regions VL - 5 SN - , 1534-7362 UR - http://www.journalofvision.org/content/5/8/1026 CP - 8 M3 - 10.1167/5.8.1026 ER - TY - JOUR T1 - Comparative Genomics of Trypanosomatid Parasitic Protozoa JF - Science Y1 - 2005 A1 - El‐Sayed, Najib M. A1 - Myler,Peter J. A1 - Blandin,Gaëlle A1 - Berriman,Matthew A1 - Crabtree,Jonathan A1 - Aggarwal,Gautam A1 - Caler,Elisabet A1 - Renauld,Hubert A1 - Worthey,Elizabeth A. A1 - Hertz-Fowler,Christiane A1 - Ghedin,Elodie A1 - Peacock,Christopher A1 - Bartholomeu,Daniella C. A1 - Haas,Brian J. A1 - Tran,Anh-Nhi A1 - Wortman,Jennifer R. A1 - Alsmark,U. Cecilia M. A1 - Angiuoli,Samuel A1 - Anupama,Atashi A1 - Badger,Jonathan A1 - Bringaud,Frederic A1 - Cadag,Eithon A1 - Carlton,Jane M. A1 - Cerqueira,Gustavo C. A1 - Creasy,Todd A1 - Delcher,Arthur L. A1 - Djikeng,Appolinaire A1 - Embley,T. Martin A1 - Hauser,Christopher A1 - Ivens,Alasdair C. A1 - Kummerfeld,Sarah K. A1 - Pereira-Leal,Jose B. A1 - Nilsson,Daniel A1 - Peterson,Jeremy A1 - Salzberg,Steven L. A1 - Shallom,Joshua A1 - Silva,Joana C. A1 - Sundaram,Jaideep A1 - Westenberger,Scott A1 - White,Owen A1 - Melville,Sara E. A1 - Donelson,John E. A1 - Andersson,Björn A1 - Stuart,Kenneth D. A1 - Hall,Neil AB - A comparison of gene content and genome architecture of Trypanosoma brucei, Trypanosoma cruzi, and Leishmania major, three related pathogens with different life cycles and disease pathology, revealed a conserved core proteome of about 6200 genes in large syntenic polycistronic gene clusters. Many species-specific genes, especially large surface antigen families, occur at nonsyntenic chromosome-internal and subtelomeric regions. Retroelements, structural RNAs, and gene family expansion are often associated with syntenic discontinuities that—along with gene divergence, acquisition and loss, and rearrangement within the syntenic regions—have shaped the genomes of each parasite. Contrary to recent reports, our analyses reveal no evidence that these species are descended from an ancestor that contained a photosynthetic endosymbiont. VL - 309 UR - http://www.sciencemag.org/content/309/5733/404.abstract CP - 5733 M3 - 10.1126/science.1112181 ER - TY - CONF T1 - Comparing the Performance of High-Level Middleware Systems in Shared and Distributed Memory Parallel Environments T2 - Parallel and Distributed Processing Symposium, 2005. Proceedings. 19th IEEE International Y1 - 2005 A1 - Kim,Jik-Soo A1 - Andrade,H. A1 - Sussman, Alan KW - Application software KW - Computer science KW - Computer vision KW - Data analysis KW - Distributed computing KW - distributed computing environment KW - distributed memory parallel environment KW - distributed shared memory systems KW - Educational institutions KW - high-level middleware system KW - I/O-intensive data analysis application KW - Libraries KW - Middleware KW - parallel computing environment KW - parallel library support KW - parallel memories KW - programming language KW - programming languages KW - Runtime environment KW - shared memory parallel environment KW - Writing AB - The utilization of toolkits for writing parallel and/or distributed applications has been shown to greatly enhance developer's productivity. Such an approach hides many of the complexities associated with writing these applications, rather than relying solely on programming language aids and parallel library support, such as MPI or PVM. In this work, we evaluate three different middleware systems that have been used to implement a computation and I/O-intensive data analysis application from the domain of computer vision. This study shows the benefits and overheads associated with each of the middleware systems, in different homogeneous computational environments and with different workloads. Our results lead the way toward being able to make better decisions for tuning the application environment, for selecting the appropriate middleware, and also for designing more powerful middleware systems to efficiently build and run highly complex applications in both parallel and distributed computing environments. JA - Parallel and Distributed Processing Symposium, 2005. Proceedings. 19th IEEE International PB - IEEE SN - 0-7695-2312-9 M3 - 10.1109/IPDPS.2005.144 ER - TY - JOUR T1 - Critical Factors Influencing the Occurrence of Vibrio Cholerae in the Environment of Bangladesh JF - Applied and Environmental MicrobiologyAppl. Environ. Microbiol. Y1 - 2005 A1 - Huq,Anwar A1 - Sack,R. Bradley A1 - Nizam,Azhar A1 - Longini,Ira M. A1 - Nair,G. Balakrish A1 - Ali,Afsar A1 - Morris,J. Glenn A1 - Khan,M. N. Huda A1 - Siddique,A. Kasem A1 - Yunus,Mohammed A1 - Albert,M. John A1 - Sack,David A. A1 - Rita R Colwell AB - The occurrence of outbreaks of cholera in Africa in 1970 and in Latin America in 1991, mainly in coastal communities, and the appearance of the new serotype Vibrio cholerae O139 in India and subsequently in Bangladesh have stimulated efforts to understand environmental factors influencing the growth and geographic distribution of epidemic Vibrio cholerae serotypes. Because of the severity of recent epidemics, cholera is now being considered by some infectious disease investigators as a “reemerging” disease, prompting new work on the ecology of vibrios. Epidemiological and ecological surveillance for cholera has been under way in four rural, geographically separated locations in Bangladesh for the past 4 years, during which both clinical and environmental samples were collected at biweekly intervals. The clinical epidemiology portion of the research has been published (Sack et al., J. Infect. Dis. 187:96-101, 2003). The results of environmental sampling and analysis of the environmental and clinical data have revealed significant correlations of water temperature, water depth, rainfall, conductivity, and copepod counts with the occurrence of cholera toxin-producing bacteria (presumably V. cholerae). The lag periods between increases or decreases in units of factors, such as temperature and salinity, and occurrence of cholera correlate with biological parameters, e.g., plankton population blooms. The new information on the ecology of V. cholerae is proving useful in developing environmental models for the prediction of cholera epidemics. VL - 71 SN - 0099-2240, 1098-5336 UR - http://aem.asm.org/content/71/8/4645 CP - 8 M3 - 10.1128/AEM.71.8.4645-4654.2005 ER - TY - CHAP T1 - Detecting Independent 3D Movement T2 - Handbook of Geometric ComputingHandbook of Geometric Computing Y1 - 2005 A1 - Corrochano,Eduardo Bayro A1 - Ogale, Abhijit S. A1 - Fermüller, Cornelia A1 - Aloimonos, J. JA - Handbook of Geometric ComputingHandbook of Geometric Computing PB - Springer Berlin Heidelberg SN - 978-3-540-28247-1 UR - http://dx.doi.org/10.1007/3-540-28247-5_12 ER - TY - CONF T1 - Discovering a language for human activity T2 - Proceedings of the AAAI 2005 Fall Symposium on Anticipatory Cognitive Embodied Systems, Washington, DC Y1 - 2005 A1 - Guerra-Filho,G. A1 - Fermüller, Cornelia A1 - Aloimonos, J. JA - Proceedings of the AAAI 2005 Fall Symposium on Anticipatory Cognitive Embodied Systems, Washington, DC ER - TY - CONF T1 - Efficient query processing on spatial networks T2 - Proceedings of the 13th annual ACM international workshop on Geographic information systems Y1 - 2005 A1 - Sankaranarayanan,Jagan A1 - Alborzi,Houman A1 - Samet, Hanan KW - location-based services KW - path coherence KW - Query processing KW - SILC framework KW - Spatial databases KW - spatial networks AB - A framework for determining the shortest path and the distance between every pair of vertices on a spatial network is presented. The framework, termed SILC, uses path coherence between the shortest path and the spatial positions of vertices on the spatial network, thereby, resulting in an encoding that is compact in representation and fast in path and distance retrievals. Using this framework, a wide variety of spatial queries such as incremental nearest neighbor searches and spatial distance joins can be shown to work on datasets of locations residing on a spatial network of sufficiently large size. The suggested framework is suitable for both main memory and disk-resident datasets. JA - Proceedings of the 13th annual ACM international workshop on Geographic information systems T3 - GIS '05 PB - ACM CY - New York, NY, USA SN - 1-59593-146-5 UR - http://doi.acm.org/10.1145/1097064.1097093 M3 - 10.1145/1097064.1097093 ER - TY - JOUR T1 - Efficient strategies for channel management in wireless lans JF - UMD, CS Tech. Rep. CS-TR Y1 - 2005 A1 - Mishra,A. A1 - Brik,V. A1 - Banerjee,S. A1 - Srinivasan, Aravind A1 - Arbaugh, William A. AB - We define efficient algorithms for channel management (channelassignment and load balancing among APs) in 802.11-based WLANs that lead to better usage of the wireless spectrum. These algorithms (called CFAssign) are based on a “conflict-free set coloring” for- mulation that jointly perform load balancing along with channel assignment. Such a formulation has a number of advantages. First, it explicitly captures interference effects at clients. Next, it intrinsi- cally exposes opportunities for better channel re-use. Finally, algo- rithms based on this formulation do not depend on specific physical RF models and hence can be applied efficiently to a wide-range of in-building as well as outdoor scenarios. We have performed extensive packet-level simulations and mea- surements on a deployed wireless testbed of 70 APs to validate the performance of our proposed algorithms. We show that in ad- dition to single network scenarios, CFAssign algorithms are well suited for channel assignment in scenarios where multiple wireless networks share the same physical space and contend for the same frequency spectrum. Our results over a wide range of scenarios indicate that CFAssign reduces the interference at clients by about 50-70% in comparison to current best-known techniques. VL - 4729 ER - TY - CONF T1 - Ego-Motion Estimation and 3D Model Refinement in Scenes with Varying Illumination T2 - Application of Computer Vision, 2005. WACV/MOTIONS '05 Volume 1. Seventh IEEE Workshops on Y1 - 2005 A1 - Agrawal,Amit K A1 - Chellapa, Rama AB - We present an iterative algorithm for robustly estimating the ego-motion and refining and updating a coarse depth map using surface parallax and a generalized dynamic image (GDI) model. Given a coarse depth map acquired by a range-finder or extracted from a Digital Elevation Map (DEM), we first estimate the ego-motion by combining a global ego-motion constraint and a local GDI model. Using the estimated camera motion and the available depth estimate, motion of the 3D points is compensated. We utilize the fact that the resulting surface parallax field is an epipolar field and constrain its direction using the previous motion estimates. We then estimate the magnitude of the parallax field and the GDI model parameters locally and use them to refine the depth map estimates. We use a tensor based approach to formulate the depth refinement procedure as an eigen-value problem and obtain confidence measures for determining the accuracy of the estimated depth values. These confidence measures are used to remove regions with potentially incorrect depth estimates for robustly estimating ego-motion in the next iteration. Experimental results using both synthetic and real data are presented. Comparisons with results obtained using a brightness constancy (BC) model show that the proposed algorithm works significantly better when time-varying illumination changes are present in the scene. JA - Application of Computer Vision, 2005. WACV/MOTIONS '05 Volume 1. Seventh IEEE Workshops on VL - 2 M3 - 10.1109/ACVMOT.2005.45 ER - TY - JOUR T1 - EvoSTOC Contributions JF - Applications of evolutionary computing: EvoWorkshops 2005, EvoBIO, EvoCOMNET, EvoHOT, EvoIASP, EvoMUSART, and EvoSTOC Y1 - 2005 A1 - Merkle,D. A1 - Middendorf,M. A1 - Scheidler,A. A1 - Avigad,G. A1 - Moshaiov,A. A1 - Brauner,N. A1 - Parsopoulos,K.E. A1 - Vrahatis,M.N. A1 - Rand, William A1 - Riolo,R ER - TY - CONF T1 - Exploiting partially overlapping channels in wireless networks: Turning a peril into an advantage T2 - Proceedings of the 5th ACM SIGCOMM conference on Internet Measurement Y1 - 2005 A1 - Mishra,A. A1 - Rozner,E. A1 - Banerjee,S. A1 - Arbaugh, William A. JA - Proceedings of the 5th ACM SIGCOMM conference on Internet Measurement ER - TY - CONF T1 - Face recognition in the presence of multiple illumination sources T2 - Computer Vision, 2005. ICCV 2005. Tenth IEEE International Conference on Y1 - 2005 A1 - Aggarwal,G. A1 - Chellapa, Rama KW - approach;estimation KW - illumination KW - Lambert KW - law;analysis-by-synthesis KW - nonlinearity;multiple KW - process;face KW - recognition;hard KW - recognition;light KW - source;face KW - sources; AB - Most existing face recognition algorithms work well for controlled images but are quite susceptible to changes in illumination and pose. This has led to the rise of analysis-by-synthesis approaches due to their inherent potential to handle these external factors. Though these approaches work quite well, most of them assume that the face is illuminated by a single light source which is usually not true in realistic conditions. In this paper, we propose an algorithm to recognize faces illuminated by arbitrarily placed, multiple light sources. The algorithm does not need to know the number of light sources and works extremely well even while recognizing faces illuminated by different number of light sources. Results using this algorithm are reported on multiple-illumination datasets generated from PIE by T. Sim, et al. (2003) and Yale Face Database B by W. Zhao, et al. (2003). We also highlight the importance of the hard non-linearity in the Lambert's law which is often ignored, probably to linearize the estimation process JA - Computer Vision, 2005. ICCV 2005. Tenth IEEE International Conference on VL - 2 M3 - 10.1109/ICCV.2005.92 ER - TY - CHAP T1 - Fault-Tolerant Middleware and the Magical 1% T2 - Middleware 2005 Y1 - 2005 A1 - Tudor Dumitras A1 - Narasimhan, Priya ED - Alonso, Gustavo KW - Computer Communication Networks KW - Information Systems Applications (incl.Internet) KW - Operating systems KW - Programming Languages, Compilers, Interpreters KW - Programming Techniques KW - software engineering AB - Through an extensive experimental analysis of over 900 possible configurations of a fault-tolerant middleware system, we present empirical evidence that the unpredictability inherent in such systems arises from merely 1% of the remote invocations. The occurrence of very high latencies cannot be regulated through parameters such as the number of clients, the replication style and degree or the request rates. However, by selectively filtering out a “magical 1%” of the raw observations of various metrics, we show that performance, in terms of measured end-to-end latency and throughput, can be bounded, easy to understand and control. This simple statistical technique enables us to guarantee, with some level of confidence, bounds for percentile-based quality of service (QoS) metrics, which dramatically increase our ability to tune and control a middleware system in a predictable manner. JA - Middleware 2005 T3 - Lecture Notes in Computer Science PB - Springer Berlin Heidelberg SN - 978-3-540-30323-7, 978-3-540-32269-6 UR - http://link.springer.com/chapter/10.1007/11587552_24 ER - TY - CHAP T1 - Fusing Depth and Video Using Rao-Blackwellized Particle Filter T2 - Pattern Recognition and Machine IntelligencePattern Recognition and Machine Intelligence Y1 - 2005 A1 - Agrawal,Amit A1 - Chellapa, Rama ED - Pal,Sankar ED - Bandyopadhyay,Sanghamitra ED - Biswas,Sambhunath AB - We address the problem of fusing sparse and noisy depth data obtained from a range finder with features obtained from intensity images to estimate ego-motion and refine 3D structure of a scene using a Rao-Blackwellized particle filter. For scenes with low depth variability, the algorithm shows an alternate way of performing Structure from Motion (SfM) starting with a flat depth map. Instead of using 3D depths, we formulate the problem using 2D image domain parallax and show that conditioned on non-linear motion parameters, the parallax magnitude with respect to the projection of the vanishing point forms a linear subsystem independent of camera motion and their distributions can be analytically integrated. Thus, the structure is obtained by estimating parallax with respect to the given depths using a Kalman filter and only the ego-motion is estimated using a particle filter. Hence, the required number of particles becomes independent of the number of feature points which is an improvement over previous algorithms. Experimental results on both synthetic and real data show the effectiveness of our approach. JA - Pattern Recognition and Machine IntelligencePattern Recognition and Machine Intelligence T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 3776 SN - 978-3-540-30506-4 UR - http://dx.doi.org/10.1007/11590316_82 ER - TY - JOUR T1 - Generating and Querying Semantic Web Environments for Photo Libraries (2005) JF - Institute for Systems Research Technical Reports Y1 - 2005 A1 - Axelrod,Adam A1 - Golbeck,Jennifer A1 - Shneiderman, Ben KW - Technical Report AB - Online photo libraries require a method to efficiently search a collection of photographs, and retrieve photos with similar attributes. Our motivation was to incorporate an existing collection of over 250 photographs of over 200 faculty members and events spanning 7 decades into a library called CS PhotoHistory that is available in hypertext and on the Semantic Web. In this paper, we identify challenges related to making this repository available on the Semantic Web, including issues of automation, modeling, and expressivity. Using CS PhotoHistory as a case study, we describe the process of creating an ontology and a querying interface for interacting with a digital photo library on the Semantic Web. UR - http://drum.lib.umd.edu/handle/1903/6538 ER - TY - CONF T1 - Generating testable hypotheses from tacit knowledge for high productivity computing T2 - Proceedings of the second international workshop on Software engineering for high performance computing system applications Y1 - 2005 A1 - Asgari, Sima A1 - Hochstein, Lorin A1 - Basili, Victor R. A1 - Zelkowitz, Marvin V A1 - Hollingsworth, Jeffrey K A1 - Carver, Jeff A1 - Shull, Forrest KW - folklore elicitation KW - high productivity development time experimental studies KW - hypothesis generation KW - tacit knowledge solicitation KW - testable hypotheses AB - In this research, we are developing our understanding of how the high performance computing community develops effective parallel implementations of programs by collecting the folklore within the community. We use this folklore as the basis for a series of experiments, which we expect, will validate or negate these assumptions. JA - Proceedings of the second international workshop on Software engineering for high performance computing system applications T3 - SE-HPCS '05 PB - ACM CY - New York, NY, USA SN - 1-59593-117-1 UR - http://doi.acm.org/10.1145/1145319.1145325 M3 - 10.1145/1145319.1145325 ER - TY - JOUR T1 - The genome of the protist parasite Entamoeba histolytica JF - Nature Y1 - 2005 A1 - Loftus,B. A1 - Anderson,I. A1 - Davies,R. A1 - Alsmark,U. C.M A1 - Samuelson,J. A1 - Amedeo,P. A1 - Roncaglia,P. A1 - Berriman,M. A1 - Hirt,R. P A1 - Mann,B. J A1 - others VL - 433 CP - 7028 ER - TY - JOUR T1 - The Genome Sequence of Trypanosoma cruzi, Etiologic Agent of Chagas Disease JF - Science Y1 - 2005 A1 - El‐Sayed, Najib M. A1 - Myler,Peter J. A1 - Bartholomeu,Daniella C. A1 - Nilsson,Daniel A1 - Aggarwal,Gautam A1 - Tran,Anh-Nhi A1 - Ghedin,Elodie A1 - Worthey,Elizabeth A. A1 - Delcher,Arthur L. A1 - Blandin,Gaëlle A1 - Westenberger,Scott J. A1 - Caler,Elisabet A1 - Cerqueira,Gustavo C. A1 - Branche,Carole A1 - Haas,Brian A1 - Anupama,Atashi A1 - Arner,Erik A1 - Åslund,Lena A1 - Attipoe,Philip A1 - Bontempi,Esteban A1 - Bringaud,Frédéric A1 - Burton,Peter A1 - Cadag,Eithon A1 - Campbell,David A. A1 - Carrington,Mark A1 - Crabtree,Jonathan A1 - Darban,Hamid A1 - da Silveira,Jose Franco A1 - de Jong,Pieter A1 - Edwards,Kimberly A1 - Englund,Paul T. A1 - Fazelina,Gholam A1 - Feldblyum,Tamara A1 - Ferella,Marcela A1 - Frasch,Alberto Carlos A1 - Gull,Keith A1 - Horn,David A1 - Hou,Lihua A1 - Huang,Yiting A1 - Kindlund,Ellen A1 - Klingbeil,Michele A1 - Kluge,Sindy A1 - Koo,Hean A1 - Lacerda,Daniela A1 - Levin,Mariano J. A1 - Lorenzi,Hernan A1 - Louie,Tin A1 - Machado,Carlos Renato A1 - McCulloch,Richard A1 - McKenna,Alan A1 - Mizuno,Yumi A1 - Mottram,Jeremy C. A1 - Nelson,Siri A1 - Ochaya,Stephen A1 - Osoegawa,Kazutoyo A1 - Pai,Grace A1 - Parsons,Marilyn A1 - Pentony,Martin A1 - Pettersson,Ulf A1 - Pop, Mihai A1 - Ramirez,Jose Luis A1 - Rinta,Joel A1 - Robertson,Laura A1 - Salzberg,Steven L. A1 - Sanchez,Daniel O. A1 - Seyler,Amber A1 - Sharma,Reuben A1 - Shetty,Jyoti A1 - Simpson,Anjana J. A1 - Sisk,Ellen A1 - Tammi,Martti T. A1 - Tarleton,Rick A1 - Teixeira,Santuza A1 - Van Aken,Susan A1 - Vogt,Christy A1 - Ward,Pauline N. A1 - Wickstead,Bill A1 - Wortman,Jennifer A1 - White,Owen A1 - Fraser,Claire M. A1 - Stuart,Kenneth D. A1 - Andersson,Björn AB - Whole-genome sequencing of the protozoan pathogen Trypanosoma cruzi revealed that the diploid genome contains a predicted 22,570 proteins encoded by genes, of which 12,570 represent allelic pairs. Over 50% of the genome consists of repeated sequences, such as retrotransposons and genes for large families of surface molecules, which include trans-sialidases, mucins, gp63s, and a large novel family (>1300 copies) of mucin-associated surface protein (MASP) genes. Analyses of the T. cruzi, T. brucei, and Leishmania major (Tritryp) genomes imply differences from other eukaryotes in DNA repair and initiation of replication and reflect their unusual mitochondrial DNA. Although the Tritryp lack several classes of signaling molecules, their kinomes contain a large and diverse set of protein kinases and phosphatases; their size and diversity imply previously unknown interactions and regulatory processes, which may be targets for intervention. VL - 309 UR - http://www.sciencemag.org/content/309/5733/409.abstract CP - 5733 M3 - 10.1126/science.1112631 ER - TY - JOUR T1 - The Genome Sequence of Trypanosoma Cruzi, Etiologic Agent of Chagas Disease JF - ScienceScience Y1 - 2005 A1 - El‐Sayed, Najib M. A1 - Myler,Peter J. A1 - Bartholomeu,Daniella C. A1 - Nilsson,Daniel A1 - Aggarwal,Gautam A1 - Tran,Anh-Nhi A1 - Ghedin,Elodie A1 - Worthey,Elizabeth A. A1 - Delcher,Arthur L. A1 - Blandin,Gaëlle A1 - Westenberger,Scott J. A1 - Caler,Elisabet A1 - Cerqueira,Gustavo C. A1 - Branche,Carole A1 - Haas,Brian A1 - Anupama,Atashi A1 - Arner,Erik A1 - Åslund,Lena A1 - Attipoe,Philip A1 - Bontempi,Esteban A1 - Bringaud,Frédéric A1 - Burton,Peter A1 - Cadag,Eithon A1 - Campbell,David A. A1 - Carrington,Mark A1 - Crabtree,Jonathan A1 - Darban,Hamid A1 - da Silveira,Jose Franco A1 - de Jong,Pieter A1 - Edwards,Kimberly A1 - Englund,Paul T. A1 - Fazelina,Gholam A1 - Feldblyum,Tamara A1 - Ferella,Marcela A1 - Frasch,Alberto Carlos A1 - Gull,Keith A1 - Horn,David A1 - Hou,Lihua A1 - Huang,Yiting A1 - Kindlund,Ellen A1 - Klingbeil,Michele A1 - Kluge,Sindy A1 - Koo,Hean A1 - Lacerda,Daniela A1 - Levin,Mariano J. A1 - Lorenzi,Hernan A1 - Louie,Tin A1 - Machado,Carlos Renato A1 - McCulloch,Richard A1 - McKenna,Alan A1 - Mizuno,Yumi A1 - Mottram,Jeremy C. A1 - Nelson,Siri A1 - Ochaya,Stephen A1 - Osoegawa,Kazutoyo A1 - Pai,Grace A1 - Parsons,Marilyn A1 - Pentony,Martin A1 - Pettersson,Ulf A1 - Pop, Mihai A1 - Ramirez,Jose Luis A1 - Rinta,Joel A1 - Robertson,Laura A1 - Salzberg,Steven L. A1 - Sanchez,Daniel O. A1 - Seyler,Amber A1 - Sharma,Reuben A1 - Shetty,Jyoti A1 - Simpson,Anjana J. A1 - Sisk,Ellen A1 - Tammi,Martti T. A1 - Tarleton,Rick A1 - Teixeira,Santuza A1 - Van Aken,Susan A1 - Vogt,Christy A1 - Ward,Pauline N. A1 - Wickstead,Bill A1 - Wortman,Jennifer A1 - White,Owen A1 - Fraser,Claire M. A1 - Stuart,Kenneth D. A1 - Andersson,Björn AB - Whole-genome sequencing of the protozoan pathogen Trypanosoma cruzi revealed that the diploid genome contains a predicted 22,570 proteins encoded by genes, of which 12,570 represent allelic pairs. Over 50% of the genome consists of repeated sequences, such as retrotransposons and genes for large families of surface molecules, which include trans-sialidases, mucins, gp63s, and a large novel family (>1300 copies) of mucin-associated surface protein (MASP) genes. Analyses of the T. cruzi, T. brucei, and Leishmania major (Tritryp) genomes imply differences from other eukaryotes in DNA repair and initiation of replication and reflect their unusual mitochondrial DNA. Although the Tritryp lack several classes of signaling molecules, their kinomes contain a large and diverse set of protein kinases and phosphatases; their size and diversity imply previously unknown interactions and regulatory processes, which may be targets for intervention. VL - 309 SN - 0036-8075, 1095-9203 UR - http://www.sciencemag.org/content/309/5733/409 CP - 5733 M3 - 10.1126/science.1112631 ER - TY - JOUR T1 - The genome sequence of Trypanosoma cruzi, etiologic agent of Chagas disease JF - Science Y1 - 2005 A1 - El-Sayed, N.M. A1 - Myler,P. J A1 - Bartholomeu,D. C A1 - Nilsson,D. A1 - Aggarwal,G. A1 - Tran,A. N A1 - Ghedin,E. A1 - Worthey,E. A A1 - Delcher,A. L A1 - Blandin,G. A1 - others VL - 309 CP - 5733 ER - TY - CONF T1 - Identifying and segmenting human-motion for mobile robot navigation using alignment errors T2 - 12th International Conference on Advanced Robotics, 2005. ICAR '05. Proceedings Y1 - 2005 A1 - Abd-Almageed, Wael A1 - Burns,B. J A1 - Davis, Larry S. KW - Computer errors KW - Educational institutions KW - Frequency estimation KW - human-motion identification KW - human-motion segmentation KW - HUMANS KW - Image motion analysis KW - Image segmentation KW - mobile robot navigation KW - Mobile robots KW - Motion estimation KW - Navigation KW - Object detection KW - robot vision KW - SHAPE AB - This paper presents a new human-motion identification and segmentation algorithm, for mobile robot platforms. The algorithm is based on computing the alignment error between pairs of object images acquired from a moving platform. Pairs of images generating relatively small alignment errors are used to estimate the fundamental frequency of the object's motion. A decision criterion is then used to test the significance of the estimated frequency and to classify the object's motion. To verify the validity of the proposed approach, experimental results are shown on different classes of objects JA - 12th International Conference on Advanced Robotics, 2005. ICAR '05. Proceedings PB - IEEE SN - 0-7803-9178-0 M3 - 10.1109/ICAR.2005.1507441 ER - TY - CHAP T1 - Image Sequence Stabilization, Mosaicking, and Superresolution T2 - Handbook of Image and Video Processing (Second Edition)Handbook of Image and Video Processing (Second Edition) Y1 - 2005 A1 - Chellapa, Rama A1 - Srinivasan, S. A1 - Aggarwal,G. A1 - Veeraraghavan,A. ED - Al Bovik AB - A sequence of temporal images gathered from a single sensor adds a whole new dimension to two-dimensional (2D) image data. Availability of an image sequence permits the measurement of quantities such as subpixel intensities, camera motion and depth, and detection and tracking of moving objects. In turn, the processing of image sequences necessitates the development of sophisticated techniques to extract this information. With the recent availability of powerful yet inexpensive computers, data storage systems, and image acquisition devices, image sequence analysis has transitioned from an esoteric research domain to a practical area with significant commercial interest. JA - Handbook of Image and Video Processing (Second Edition)Handbook of Image and Video Processing (Second Edition) PB - Academic Press CY - Burlington SN - 978-0-12-119792-6 UR - http://www.sciencedirect.com/science/article/pii/B9780121197926500826 ER - TY - CHAP T1 - Information Visualization and the Challenge of Universal Usability T2 - Exploring GeovisualizationExploring Geovisualization Y1 - 2005 A1 - Plaisant, Catherine ED - Jason Dykes ED - Alan M. MacEachren and Menno-Jan KraakA2 - Jason Dykes,Alan M. MacEachren ED - Menno-Jan Kraak AB - Information Visualization aims to provide compact graphical presentations and user interfaces for interactively manipulating large numbers of items. We present a simple “data by tasks taxonomy” then discuss the challenges of providing universal usability, with example applications using geo-referenced data. Information Visualization has been shown to be a powerful visual thinking or decision tool but it is becoming important for services to reach and empower every citizen. Technological advances are needed to deal with user diversity (age, language, disabilities, etc.) but also with the variety of technology used (screen size, network speed, etc.) and the gaps in user's knowledge (general knowledge, knowledge of the application domain, of the interface syntax or semantic). We present examples that illustrate how those challenges can be addressed. JA - Exploring GeovisualizationExploring Geovisualization PB - Elsevier CY - Oxford SN - 978-0-08-044531-1 UR - http://www.sciencedirect.com/science/article/pii/B9780080445311504218 ER - TY - JOUR T1 - Interactive pattern search in time series JF - Proceedings of SPIE Y1 - 2005 A1 - Buono,Paolo A1 - Aris,Aleks A1 - Plaisant, Catherine A1 - Khella,Amir A1 - Shneiderman, Ben AB - The need for pattern discovery in long time series data led researchers to develop algorithms for similarity search. Most of the literature about time series focuses on algorithms that index time series and bring the data into the main storage, thus providing fast information retrieval on large time series. This paper reviews the state of the art in visualizing time series, and focuses on techniques that enable users to visually and interactively query time series. Then, it presents TimeSearcher 2, a tool that enables users to explore multidimensional data using synchronized tables and graphs with overview+detail, filter the time series data to reduce the scope of the search, select an existing pattern to find similar occurrences, and interactively adjust similarity parameters to narrow the result set. This tool is an extension of previous work, TimeSearcher 1, which uses graphical timeboxes to interactively query time series data. VL - 5669 SN - 0277786X UR - http://spiedigitallibrary.org/proceedings/resource/2/psisdg/5669/1/175_1?isAuthorized=no CP - 1 M3 - doi:10.1117/12.587537 ER - TY - RPRT T1 - Interactive Pattern Search in Time Series (2004) Y1 - 2005 A1 - Buono,Paolo A1 - Aris,Aleks A1 - Plaisant, Catherine A1 - Khella,Amir A1 - Shneiderman, Ben KW - Technical Report AB - The need for pattern discovery in long time series data led researchers to develop algorithms for similarity search. Most of the literature about time series focuses on algorithms that index time series and bring the data into the main storage, thus providing fast information retrieval on large time series. This paper reviews the state of the art in visualizing time series, and focuses on techniques that enable users to interactively query time series. Then it presents TimeSearcher 2, a tool that enables users to explore multidimensional data using coordinated tables and graphs with overview+detail, filter the time series data to reduce the scope of the search, select an existing pattern to find similar occurrences, and interactively adjust similarity parameters to narrow the result set. This tool is an extension of previous work, TimeSearcher 1, which uses graphical timeboxes to interactively query time series data. JA - Institute for Systems Research Technical Reports UR - http://drum.lib.umd.edu/handle/1903/6519 ER - TY - CONF T1 - The Java memory model T2 - Proceedings of the 32nd ACM SIGPLAN-SIGACT symposium on Principles of programming languages Y1 - 2005 A1 - Manson,Jeremy A1 - Pugh, William A1 - Adve,Sarita V. KW - concurrency KW - java KW - memory model KW - Multithreading AB - This paper describes the new Java memory model, which has been revised as part of Java 5.0. The model specifies the legal behaviors for a multithreaded program; it defines the semantics of multithreaded Java programs and partially determines legal implementations of Java virtual machines and compilers.The new Java model provides a simple interface for correctly synchronized programs -- it guarantees sequential consistency to data-race-free programs. Its novel contribution is requiring that the behavior of incorrectly synchronized programs be bounded by a well defined notion of causality. The causality requirement is strong enough to respect the safety and security properties of Java and weak enough to allow standard compiler and hardware optimizations. To our knowledge, other models are either too weak because they do not provide for sufficient safety/security, or are too strong because they rely on a strong notion of data and control dependences that precludes some standard compiler transformations.Although the majority of what is currently done in compilers is legal, the new model introduces significant differences, and clearly defines the boundaries of legal transformations. For example, the commonly accepted definition for control dependence is incorrect for Java, and transformations based on it may be invalid.In addition to providing the official memory model for Java, we believe the model described here could prove to be a useful basis for other programming languages that currently lack well-defined models, such as C++ and C#. JA - Proceedings of the 32nd ACM SIGPLAN-SIGACT symposium on Principles of programming languages T3 - POPL '05 PB - ACM CY - New York, NY, USA SN - 1-58113-830-X UR - http://doi.acm.org/10.1145/1040305.1040336 M3 - 10.1145/1040305.1040336 ER - TY - CONF T1 - Learning approximate preconditions for methods in hierarchical plans Y1 - 2005 A1 - Ilghami,Okhtay A1 - Muñoz-Avila,Héctor A1 - Nau, Dana S. A1 - Aha,David W. AB - A significant challenge in developing planning systems for practical applications is the difficulty of acquiring the domain knowledge needed by such systems. One method for acquiring this knowledge is to learn it from plan traces, but this method typically requires a huge number of plan traces to converge. In this paper, we show that the problem with slow convergence can be circumvented by having the learner generate solution plans even before the planning domain is completely learned. Our empirical results show that these improvements reduce the size of the training set that is needed to find correct answers to a large percentage of planning problems in the test set. T3 - ICML '05 PB - ACM CY - New York, NY, USA SN - 1-59593-180-5 UR - http://doi.acm.org/10.1145/1102351.1102394 M3 - 10.1145/1102351.1102394 ER - TY - CONF T1 - A learning automata based power management for ad-hoc networks T2 - 2005 IEEE International Conference on Systems, Man and Cybernetics Y1 - 2005 A1 - El-Osery,A. I A1 - Baird,D. A1 - Abd-Almageed, Wael KW - ad hoc networks KW - ad-hoc networks KW - Computer network management KW - Computer networks KW - Energy management KW - Engineering management KW - learning automata KW - network metrics KW - network simulator KW - packet retransmissions KW - power control KW - power system management KW - power transmission control KW - stochastic learning automata KW - stochastic learning automta KW - Stochastic processes KW - system bandwidth KW - Technology management KW - Throughput KW - transmission power control KW - transmission power level KW - transmission power management AB - Power management is a very important aspect of ad-hoc networks. It directly impacts the network throughput among other network metrics. On the other hand, transmission power management may result in disconnected networks and increased level of collisions. In this paper, we introduce a transmission power control based on stochastic learning automata (SLA) to modify the transmission power. Based on the level of successful transmissions and the level of packet retransmissions, the SLA will modify the transmission power level either by increasing it or decreasing it. The probabilistic nature of SLA makes it a useful choice for ad-hoc networks. Using the network simulator NS, we show that using SLA for transmission power will result in an increased system bandwidth and a decrease in the collision levels. JA - 2005 IEEE International Conference on Systems, Man and Cybernetics PB - IEEE VL - 4 SN - 0-7803-9298-1 M3 - 10.1109/ICSMC.2005.1571701 ER - TY - JOUR T1 - Learning preconditions for planning from plan traces and HTN structure JF - Computational Intelligence Y1 - 2005 A1 - Ilghami,Okhtay A1 - Nau, Dana S. A1 - Muñoz-Avila,Héctor A1 - Aha,David W. KW - candidate elimination KW - HTN planning KW - learning KW - version spaces AB - A great challenge in developing planning systems for practical applications is the difficulty of acquiring the domain information needed to guide such systems. This paper describes a way to learn some of that knowledge. More specifically, the following points are discussed. (1) We introduce a theoretical basis for formally defining algorithms that learn preconditions for Hierarchical Task Network (HTN) methods. (2) We describe Candidate Elimination Method Learner (CaMeL), a supervised, eager, and incremental learning process for preconditions of HTN methods. We state and prove theorems about CaMeL's soundness, completeness, and convergence properties. (3) We present empirical results about CaMeL's convergence under various conditions. Among other things, CaMeL converges the fastest on the preconditions of the HTN methods that are needed the most often. Thus CaMeL's output can be useful even before it has fully converged. VL - 21 SN - 1467-8640 UR - http://onlinelibrary.wiley.com/doi/10.1111/j.1467-8640.2005.00279.x/abstract CP - 4 M3 - 10.1111/j.1467-8640.2005.00279.x ER - TY - JOUR T1 - Logic, self-awareness and self-improvement: The metacognitive loop and the problem of brittleness JF - Journal of Logic and Computation Y1 - 2005 A1 - Anderson,M. L A1 - Perlis, Don VL - 15 CP - 1 ER - TY - JOUR T1 - Matching shape sequences in video with applications in human movement analysis JF - Pattern Analysis and Machine Intelligence, IEEE Transactions on Y1 - 2005 A1 - A,Veeraraghavan A1 - Roy-Chowdhury, A.K. A1 - Chellapa, Rama KW - Automated;Photography;Reproducibility of Results;Sensitivity and Specificity;Subtraction Technique;Video Recording; KW - autoregressive moving average model;deforming shapes;dynamic time-warping;feature extraction;gait-based human recognition;human movement analysis;matching shape sequences;video;autoregressive moving average processes;feature extraction;image matching;imag KW - Biological;Models KW - Computer-Assisted;Imaging KW - Statistical;Movement;Pattern Recognition KW - Three-Dimensional;Leg;Models AB - We present an approach for comparing two sequences of deforming shapes using both parametric models and nonparametric methods. In our approach, Kendall's definition of shape is used for feature extraction. Since the shape feature rests on a non-Euclidean manifold, we propose parametric models like the autoregressive model and autoregressive moving average model on the tangent space and demonstrate the ability of these models to capture the nature of shape deformations using experiments on gait-based human recognition. The nonparametric model is based on dynamic time-warping. We suggest a modification of the dynamic time-warping algorithm to include the nature of the non-Euclidean space in which the shape deformations take place. We also show the efficacy of this algorithm by its application to gait-based human recognition. We exploit the shape deformations of a person's silhouette as a discriminating feature and provide recognition results using the nonparametric model. Our analysis leads to some interesting observations on the role of shape and kinematics in automated gait-based person authentication. VL - 27 SN - 0162-8828 CP - 12 M3 - 10.1109/TPAMI.2005.246 ER - TY - CONF T1 - Measuring productivity on high performance computers T2 - 11th IEEE International Symposium on Software Metric Y1 - 2005 A1 - Zelkowitz, Marvin V A1 - Basili, Victor R. A1 - Asgari, S. A1 - Hochstein, L. A1 - Hollingsworth, Jeffrey K A1 - Nakamura, T. AB - In the high performance computing domain, the speed ofexecution of a program has typically been the primary performance metric. But productivity is also of concern to high performance computing developers. In this paper we will discuss the problems of defining and measuring productivity for these machines and we develop a model of productivity that includes both a performance component and a component that measures the development time of the program. We ran several experiments using students in high performance courses at several universities, and we report on those results with respect to our model of productivity. JA - 11th IEEE International Symposium on Software Metric ER - TY - CONF T1 - Metacognition for dropping and reconsidering intentions T2 - AAAI Spring Symposium on Metacognition in Computation Y1 - 2005 A1 - Josyula,D. P A1 - Anderson,M. L A1 - Perlis, Don JA - AAAI Spring Symposium on Metacognition in Computation ER - TY - PAT T1 - Method and system for providing physical security in an area of interest Y1 - 2005 A1 - Agrawala, Ashok K. A1 - Youssef,Moustafa Amin A1 - Shahamat,Layla AB - A system for detecting the presence of an intruder in a protected area utilizes a received signal strength indicator (RSSI) value of signals broadcast from transmitting stations deployed in the protected area. The system includes monitoring points for receiving broadcast signals, measuring the RSSI values of the received signals, and transmitting the measured RSSI values to a security system server. The security system server analyzes the RSSI values, and initiates security measures when the physical security of the protected area is violated which is detected when the measured RSSI values deviate from a predetermined strength of the broadcast signals. The security system also has the ability to track objects in the protected area and keep track of their movement in real time and report such movement. The system may be based on a Wi-Fi infrastructure in the protected area. VL - 10/916,545 UR - http://www.google.com/patents?id=VIaWAAAAEBAJ ER - TY - JOUR T1 - Motion segmentation using occlusions JF - IEEE Transactions on Pattern Analysis and Machine Intelligence Y1 - 2005 A1 - Ogale, A. S A1 - Fermüller, Cornelia A1 - Aloimonos, J. KW - 3D motion estimation KW - algorithms KW - Artificial intelligence KW - CAMERAS KW - Computer vision KW - Filling KW - hidden feature removal KW - Image Enhancement KW - Image Interpretation, Computer-Assisted KW - image motion KW - Image motion analysis KW - Image segmentation KW - Layout KW - MOTION KW - Motion detection KW - Motion estimation KW - motion segmentation KW - Movement KW - Object detection KW - occlusion KW - occlusions KW - optical flow KW - ordinal depth KW - Pattern Recognition, Automated KW - Photography KW - Reproducibility of results KW - segmentation KW - Semiconductor device modeling KW - Sensitivity and Specificity KW - video analysis. KW - Video Recording AB - We examine the key role of occlusions in finding independently moving objects instantaneously in a video obtained by a moving camera with a restricted field of view. In this problem, the image motion is caused by the combined effect of camera motion (egomotion), structure (depth), and the independent motion of scene entities. For a camera with a restricted field of view undergoing a small motion between frames, there exists, in general, a set of 3D camera motions compatible with the observed flow field even if only a small amount of noise is present, leading to ambiguous 3D motion estimates. If separable sets of solutions exist, motion-based clustering can detect one category of moving objects. Even if a single inseparable set of solutions is found, we show that occlusion information can be used to find ordinal depth, which is critical in identifying a new class of moving objects. In order to find ordinal depth, occlusions must not only be known, but they must also be filled (grouped) with optical flow from neighboring regions. We present a novel algorithm for filling occlusions and deducing ordinal depth under general circumstances. Finally, we describe another category of moving objects which is detected using cardinal comparisons between structure from motion and structure estimates from another source (e.g., stereo). VL - 27 SN - 0162-8828 CP - 6 M3 - 10.1109/TPAMI.2005.123 ER - TY - CHAP T1 - Moving Object Detection and Compression in IR Sequences T2 - Computer Vision Beyond the Visible SpectrumComputer Vision Beyond the Visible Spectrum Y1 - 2005 A1 - Vaswani,Namrata A1 - Agrawal,Amit A1 - Qinfen Zheng A1 - Chellapa, Rama ED - Bhanu,Bir ED - Pavlidis,Ioannis AB - We consider the problem of remote surveillance using infrared (IR) sensors. The aim is to use IR image sequences to detect moving objects (humans or vehicles), and to transmit a few “best-view images” of every new object that is detected. Since the available bandwidth is usually low, if the object chip is big, it needs to be compressed before being transmitted. Due to low computational power of computing devices attached to the sensor, the algorithms should be computationally simple. We present two approaches for object detection — one which specifically solves the more difficult long-range object detection problem, and the other for objects at short range. For objects at short range, we also present techniques for selecting a single best-view object chip and computationally simple techniques for compressing it to very low bit rates due to the channel bandwidth constraint. A fast image chip compression scheme implemented in the wavelet domain by combining a non-iterative zerotree coding method with 2D-DPCM for both low-and high-frequency subbands is presented. Comparisons with some existing schemes are also included. The object detection and compression algorithms have been implemented in C/C++ and their performance has been evaluated using the Hitachi’s SH4 platform with software simulation. JA - Computer Vision Beyond the Visible SpectrumComputer Vision Beyond the Visible Spectrum T3 - Advances in Pattern Recognition PB - Springer London SN - 978-1-84628-065-8 UR - http://dx.doi.org/10.1007/1-84628-065-6_5 ER - TY - CONF T1 - Moving Object Segmentation and Dynamic Scene Reconstruction Using Two Frames T2 - Acoustics, Speech, and Signal Processing, 2005. Proceedings. (ICASSP '05). IEEE International Conference on Y1 - 2005 A1 - Agrawala, Ashok K. A1 - Chellapa, Rama KW - 3D KW - analysis; KW - constraints; KW - dynamic KW - ego-motion KW - estimation; KW - flow KW - image KW - images; KW - independent KW - INTENSITY KW - least KW - mean KW - median KW - method; KW - methods; KW - model; KW - MOTION KW - motion; KW - moving KW - object KW - of KW - parallax KW - parallax; KW - parametric KW - processing; KW - reconstruction; KW - scene KW - segmentation; KW - signal KW - squares KW - squares; KW - static KW - structure; KW - subspace KW - surface KW - translational KW - two-frame KW - unconstrained KW - video JA - Acoustics, Speech, and Signal Processing, 2005. Proceedings. (ICASSP '05). IEEE International Conference on VL - 2 M3 - 10.1109/ICASSP.2005.1415502 ER - TY - CONF T1 - NeurAlign: combining word alignments using neural networks T2 - Proceedings of the conference on Human Language Technology and Empirical Methods in Natural Language Processing Y1 - 2005 A1 - Ayan,Necip Fazil A1 - Dorr, Bonnie J A1 - Monz,Christof AB - This paper presents a novel approach to combining different word alignments. We view word alignment as a pattern classification problem, where alignment combination is treated as a classifier ensemble, and alignment links are adorned with linguistic features. A neural network model is used to learn word alignments from the individual alignment systems. We show that our alignment combination approach yields a significant 20--34% relative error reduction over the best-known alignment combination technique on English-Spanish and English-Chinese data. JA - Proceedings of the conference on Human Language Technology and Empirical Methods in Natural Language Processing T3 - HLT '05 PB - Association for Computational Linguistics CY - Stroudsburg, PA, USA UR - http://dx.doi.org/10.3115/1220575.1220584 M3 - 10.3115/1220575.1220584 ER - TY - CHAP T1 - Pattern Recognition in Video T2 - Pattern Recognition and Machine IntelligencePattern Recognition and Machine Intelligence Y1 - 2005 A1 - Chellapa, Rama A1 - Veeraraghavan,Ashok A1 - Aggarwal,Gaurav ED - Pal,Sankar ED - Bandyopadhyay,Sanghamitra ED - Biswas,Sambhunath AB - Images constitute data that live in a very high dimensional space, typically of the order of hundred thousand dimensions. Drawing inferences from correlated data of such high dimensions often becomes intractable. Therefore traditionally several of these problems like face recognition, object recognition, scene understanding etc. have been approached using techniques in pattern recognition. Such methods in conjunction with methods for dimensionality reduction have been highly popular and successful in tackling several image processing tasks. Of late, the advent of cheap, high quality video cameras has generated new interests in extending still image-based recognition methodologies to video sequences. The added temporal dimension in these videos makes problems like face and gait-based human recognition, event detection, activity recognition addressable. Our research has focussed on solving several of these problems through a pattern recognition approach. Of course, in video streams patterns refer to both patterns in the spatial structure of image intensities around interest points and temporal patterns that arise either due to camera motion or object motion. In this paper, we discuss the applications of pattern recognition in video to problems like face and gait-based human recognition, behavior classification, activity recognition and activity based person identification. JA - Pattern Recognition and Machine IntelligencePattern Recognition and Machine Intelligence T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 3776 SN - 978-3-540-30506-4 UR - http://dx.doi.org/10.1007/11590316_2 ER - TY - CONF T1 - Pedestrian classification from moving platforms using cyclic motion pattern T2 - IEEE International Conference on Image Processing, 2005. ICIP 2005 Y1 - 2005 A1 - Yang Ran A1 - Qinfen Zheng A1 - Weiss, I. A1 - Davis, Larry S. A1 - Abd-Almageed, Wael A1 - Liang Zhao KW - compact shape representation KW - cyclic motion pattern KW - data mining KW - Detectors KW - digital phase locked loop KW - digital phase locked loops KW - feedback loop module KW - gait analysis KW - gait phase information KW - human body pixel oscillations KW - HUMANS KW - image classification KW - Image motion analysis KW - image representation KW - image sequence KW - Image sequences KW - Motion detection KW - Object detection KW - pedestrian classification KW - pedestrian detection system KW - Phase estimation KW - Phase locked loops KW - principle gait angle KW - SHAPE KW - tracking KW - Videos AB - This paper describes an efficient pedestrian detection system for videos acquired from moving platforms. Given a detected and tracked object as a sequence of images within a bounding box, we describe the periodic signature of its motion pattern using a twin-pendulum model. Then a principle gait angle is extracted in every frame providing gait phase information. By estimating the periodicity from the phase data using a digital phase locked loop (dPLL), we quantify the cyclic pattern of the object, which helps us to continuously classify it as a pedestrian. Past approaches have used shape detectors applied to a single image or classifiers based on human body pixel oscillations, but ours is the first to integrate a global cyclic motion model and periodicity analysis. Novel contributions of this paper include: i) development of a compact shape representation of cyclic motion as a signature for a pedestrian, ii) estimation of gait period via a feedback loop module, and iii) implementation of a fast online pedestrian classification system which operates on videos acquired from moving platforms. JA - IEEE International Conference on Image Processing, 2005. ICIP 2005 PB - IEEE VL - 2 SN - 0-7803-9134-9 M3 - 10.1109/ICIP.2005.1530190 ER - TY - CONF T1 - Pedestrian classification from moving platforms using cyclic motion pattern T2 - Image Processing, 2005. ICIP 2005. IEEE International Conference on Y1 - 2005 A1 - Yang Ran A1 - Qinfen Zheng A1 - Weiss, I. A1 - Davis, Larry S. A1 - Abd-Almageed, Wael A1 - Liang Zhao KW - analysis; KW - angle; KW - body KW - classification; KW - compact KW - cyclic KW - DETECTION KW - detection; KW - digital KW - Feedback KW - Gait KW - human KW - image KW - information; KW - locked KW - loop KW - loop; KW - loops; KW - module; KW - MOTION KW - object KW - oscillations; KW - pattern; KW - pedestrian KW - phase KW - Pixel KW - principle KW - representation; KW - sequence; KW - sequences; KW - SHAPE KW - system; AB - This paper describes an efficient pedestrian detection system for videos acquired from moving platforms. Given a detected and tracked object as a sequence of images within a bounding box, we describe the periodic signature of its motion pattern using a twin-pendulum model. Then a principle gait angle is extracted in every frame providing gait phase information. By estimating the periodicity from the phase data using a digital phase locked loop (dPLL), we quantify the cyclic pattern of the object, which helps us to continuously classify it as a pedestrian. Past approaches have used shape detectors applied to a single image or classifiers based on human body pixel oscillations, but ours is the first to integrate a global cyclic motion model and periodicity analysis. Novel contributions of this paper include: i) development of a compact shape representation of cyclic motion as a signature for a pedestrian, ii) estimation of gait period via a feedback loop module, and iii) implementation of a fast online pedestrian classification system which operates on videos acquired from moving platforms. JA - Image Processing, 2005. ICIP 2005. IEEE International Conference on VL - 2 M3 - 10.1109/ICIP.2005.1530190 ER - TY - CONF T1 - Query planning for the grid: adapting to dynamic resource availability T2 - Cluster Computing and the Grid, IEEE International Symposium on Y1 - 2005 A1 - Zhang,K. A1 - Andrade,H. A1 - Raschid, Louiqa A1 - Sussman, Alan AB - The availability of massive datasets, comprising sensor measurements or the results of scientific simulations, has had a significant impact on the methodology of scientific reasoning. Scientists require storage, bandwidth and computational capacity to query and analyze these datasets, to understand physical phenomena or to test hypotheses. This paper addresses the challenge of identifying and selecting resources to develop an evaluation plan for large scale data analysis queries when data processing capabilities and datasets are dispersed across nodes in one or more computing and storage clusters. We show that generating an optimal plan is hard and we propose heuristic techniques to find a good choice of resources. We also consider heuristics to cope with dynamic resource availability; in this situation we have stale information about reusable cached results (datasets) and the load on various nodes. JA - Cluster Computing and the Grid, IEEE International Symposium on PB - IEEE Computer Society CY - Los Alamitos, CA, USA VL - 2 SN - 0-7803-9074-1 M3 - http://doi.ieeecomputersociety.org/10.1109/CCGRID.2005.1558638 ER - TY - CONF T1 - On the reasoning of real-world agents: Toward a semantics for active logic T2 - 7-th Annual Symposium on the Logical Formalization of Commonsense Reasoning Y1 - 2005 A1 - Anderson,M. L A1 - Gomaa,W. A1 - Grant,J. A1 - Perlis, Don JA - 7-th Annual Symposium on the Logical Formalization of Commonsense Reasoning ER - TY - CHAP T1 - Representing Unevenly-Spaced Time Series Data for Visualization and Interactive Exploration T2 - Human-Computer Interaction - INTERACT 2005Human-Computer Interaction - INTERACT 2005 Y1 - 2005 A1 - Aris,Aleks A1 - Shneiderman, Ben A1 - Plaisant, Catherine A1 - Shmueli,Galit A1 - Jank,Wolfgang ED - Costabile,Maria ED - Paternò,Fabio AB - Visualizing time series is useful to support discovery of relations and patterns in financial, genomic, medical and other applications. Often, measurements are equally spaced over time. We discuss the challenges of unevenly-spaced time series and present fourrepresentationmethods: sampled events, aggregated sampled events, event index and interleaved event index. We developed these methods while studying eBay auction data with TimeSearcher. We describe the advantages, disadvantages, choices for algorithms and parameters, and compare the different methods for different tasks. Interaction issues such as screen resolution, response time for dynamic queries, and learnability are governed by these decisions. JA - Human-Computer Interaction - INTERACT 2005Human-Computer Interaction - INTERACT 2005 T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 3585 SN - 978-3-540-28943-2 UR - http://dx.doi.org/10.1007/11555261_66 ER - TY - JOUR T1 - Representing Unevenly-Spaced Time Series Data for Visualization and Interactive Exploration (2005) JF - Institute for Systems Research Technical Reports Y1 - 2005 A1 - Aris,Aleks A1 - Shneiderman, Ben A1 - Plaisant, Catherine A1 - Shmueli,Galit A1 - Jank,Wolfgang KW - Technical Report AB - Visualizing time series data is useful to support discovery of relations and patterns in financial, genomic, medical and other applications. In most time series, measurements are equally spaced over time. This paper discusses the challenges for unevenly-spaced time series data and presents four methods to represent them: sampled events, aggregated sampled events, event index and interleaved event index. We developed these methods while studying eBay auction data with TimeSearcher. We describe the advantages, disadvantages, choices for algorithms and parameters, and compare the different methods. Since each method has its advantages, this paper provides guidance for choosing the right combination of methods, algorithms, and parameters to solve a given problem for unevenly-spaced time series. Interaction issues such as screen resolution, response time for dynamic queries, and meaning of the visual display are governed by these decisions. UR - http://drum.lib.umd.edu/handle/1903/6537 ER - TY - CONF T1 - Robust Contrast Invariant Stereo Correspondence T2 - Proceedings of the 2005 IEEE International Conference on Robotics and Automation, 2005. ICRA 2005 Y1 - 2005 A1 - Ogale, A. S A1 - Aloimonos, J. KW - Apertures KW - Calibration KW - CAMERAS KW - Computer science KW - contrast invariance KW - diffusion KW - Educational institutions KW - Frequency KW - gabor KW - Hardware KW - occlusions KW - Robot vision systems KW - Robotics and automation KW - Robustness KW - stereo AB - A stereo pair of cameras attached to a robot will inevitably yield images with different contrast. Even if we assume that the camera hardware is identical, due to slightly different points of view, the amount of light entering the two cameras is also different, causing dynamically adjusted internal parameters such as aperture, exposure and gain to be different. Due to the difficulty of obtaining and maintaining precise intensity or color calibration between the two cameras, contrast invariance becomes an extremely desirable property of stereo correspondence algorithms. The problem of achieving point correspondence between a stereo pair of images is often addressed by using the intensity or color differences as a local matching metric, which is sensitive to contrast changes. We present an algorithm for contrast invariant stereo matching which relies on multiple spatial frequency channels for local matching. A fast global framework uses the local matching to compute the correspondences and find the occlusions. We demonstrate that the use of multiple frequency channels allows the algorithm to yield good results even in the presence of significant amounts of noise. JA - Proceedings of the 2005 IEEE International Conference on Robotics and Automation, 2005. ICRA 2005 PB - IEEE SN - 0-7803-8914-X M3 - 10.1109/ROBOT.2005.1570218 ER - TY - JOUR T1 - Robust routing in malicious environment for ad hoc networks JF - Information Security Practice and Experience Y1 - 2005 A1 - Yu,Z. A1 - Seng,C. Y A1 - Jiang,T. A1 - Wu,X. A1 - Arbaugh, William A. ER - TY - JOUR T1 - ROMER: resilient opportunistic mesh routing for wireless mesh networks JF - Proc. of IEEE WiMesh Y1 - 2005 A1 - Yuan,Y. A1 - Yang,H. A1 - Wong,S. H.Y A1 - Lu,S. A1 - Arbaugh, William A. VL - 166 ER - TY - JOUR T1 - The roots of self-awareness JF - Phenomenology and the Cognitive Sciences Y1 - 2005 A1 - Anderson,M. L A1 - Perlis, Don VL - 4 CP - 3 ER - TY - JOUR T1 - Shape and the stereo correspondence problem JF - International Journal of Computer Vision Y1 - 2005 A1 - Ogale, A. S A1 - Aloimonos, J. VL - 65 CP - 3 ER - TY - CONF T1 - Space-time tradeoffs for approximate spherical range counting T2 - Proceedings of the sixteenth annual ACM-SIAM symposium on Discrete algorithms Y1 - 2005 A1 - Arya,Sunil A1 - Malamatos,Theocharis A1 - Mount, Dave AB - We present space-time tradeoffs for approximate spherical range counting queries. Given a set S of n data points in Rd along with a positive approximation factor ε, the goal is to preprocess the points so that, given any Euclidean ball B, we can return the number of points of any subset of S that contains all the points within a (1 - ε)-factor contraction of B, but contains no points that lie outside a (1 + ε)-factor expansion of B.In many applications of range searching it is desirable to offer a tradeoff between space and query time. We present here the first such tradeoffs for approximate range counting queries. Given 0 < ε ≤ 1/2 and a parameter γ, where 2 ≤ γ ≤ 1/ε, we show how to construct a data structure of space O(nγd log (1/ε)) that allows us to answer ε-approximate spherical range counting queries in time O(log(nγ) + 1/(εγd-1). The data structure can be built in time O(nγd log (n/ε)) log (1/ε)). Here n, ε, and γ are asymptotic quantities, and the dimension d is assumed to be a fixed constant.At one extreme (low space), this yields a data structure of space O(n log (1/e)) that can answer approximate range queries in time O(logn + 1/(ed-1) which, up to a factor of O(n log (1/e) in space, matches the best known result for approximate spherical range counting queries. At the other extreme (high space), it yields a data structure of space O((n/ed) log(1/ε)) that can answer queries in time O(logn + 1/ε). This is the fastest known query time for this problem.We also show how to adapt these data structures to the problem of computing an ε-approximation to the kth nearest neighbor, where k is any integer from 1 to n given at query time. The space bounds are identical to the range searching results, and the query time is larger only by a factor of O(1/(εγ)).Our approach is broadly based on methods developed for approximate Voronoi diagrams (AVDs), but it involves a number of significant extensions from the context of nearest neighbor searching to range searching. These include generalizing AVD node-separation properties from leaves to internal nodes of the tree and constructing efficient generator sets through a radial decomposition of space. We have also developed new arguments to analyze the time and space requirements in this more general setting. JA - Proceedings of the sixteenth annual ACM-SIAM symposium on Discrete algorithms T3 - SODA '05 PB - Society for Industrial and Applied Mathematics CY - Philadelphia, PA, USA SN - 0-89871-585-7 UR - http://dl.acm.org/citation.cfm?id=1070432.1070505 ER - TY - JOUR T1 - Structural Determinants for Selective Recognition of a Lys48-Linked Polyubiquitin Chain by a UBA Domain JF - Molecular Cell Y1 - 2005 A1 - Varadan,Ranjani A1 - Assfalg,Michael A1 - Raasi,Shahri A1 - Pickart,Cecile A1 - Fushman, David AB - SummaryAlthough functional diversity in polyubiquitin chain signaling has been ascribed to the ability of differently linked chains to bind in a distinctive manner to effector proteins, structural models of such interactions have been lacking. Here, we use NMR to unveil the structural basis of selective recognition of Lys48-linked di- and tetraubiquitin chains by the UBA2 domain of hHR23A. Although the interaction of UBA2 with Lys48-linked diubiquitin involves the same hydrophobic surface on each ubiquitin unit as that utilized in monoubiquitin:UBA complexes, our results show how the “closed” conformation of Lys48-linked diubiquitin is crucial for high-affinity binding. Moreover, recognition of Lys48-linked diubiquitin involves a unique epitope on UBA, which allows the formation of a sandwich-like diubiqutin:UBA complex. Studies of the UBA-tetraubiquitin interaction suggest that this mode of UBA binding to diubiquitin is relevant for longer chains. VL - 18 SN - 1097-2765 UR - http://www.sciencedirect.com/science/article/pii/S1097276505013195 CP - 6 M3 - 10.1016/j.molcel.2005.05.013 ER - TY - CONF T1 - Toward resilient security in wireless sensor networks T2 - Proceedings of the 6th ACM international symposium on Mobile ad hoc networking and computing Y1 - 2005 A1 - Yang,H. A1 - Ye,F. A1 - Yuan,Y. A1 - Lu,S. A1 - Arbaugh, William A. JA - Proceedings of the 6th ACM international symposium on Mobile ad hoc networking and computing ER - TY - CONF T1 - Turning information visualization innovations into commercial products: lessons to guide the next success T2 - IEEE Symposium on Information Visualization, 2005. INFOVIS 2005 Y1 - 2005 A1 - Shneiderman, Ben A1 - Rao,R. A1 - Andrews,K. A1 - Ahlberg,C. A1 - Brodbeck,D. A1 - Jewitt,T. A1 - Mackinlay,J. KW - Books KW - commercial development KW - commercial product KW - Computer interfaces KW - Computer science KW - data visualisation KW - Data visualization KW - Educational institutions KW - exploratory data analysis KW - information visualization innovation KW - information visualization tool KW - innovation management KW - Laboratories KW - Management training KW - new technology emergence KW - Technological innovation KW - technology transfer KW - Turning KW - User interfaces AB - As information visualization matures as an academic research field, commercial spinoffs are proliferating, but success stories are harder to find. This is the normal process of emergence for new technologies, but the panel organizers believe that there are certain strategies that facilitate success. To teach these lessons, we have invited several key figures who are seeking to commercialize information visualization tools. The panelists make short presentations, engage in a moderated discussion, and respond to audience questions. JA - IEEE Symposium on Information Visualization, 2005. INFOVIS 2005 PB - IEEE SN - 0-7803-9464-X M3 - 10.1109/INFVIS.2005.1532153 ER - TY - CONF T1 - UMD Experiments with FRGC Data T2 - Computer Vision and Pattern Recognition - Workshops, 2005. CVPR Workshops. IEEE Computer Society Conference on Y1 - 2005 A1 - Aggarwal,G. A1 - Biswas,S. A1 - Chellapa, Rama AB - Although significant work has been done in the field of face recognition, the performance of state-of-the art face recognition algorithms is not good enough to be effective in operational systems. Though most algorithms work well for controlled images, they are quite susceptible to changes in illumination and pose. Face Recognition Grand Challenge (FRGC) is an effort to examine such issues to suitably guide future research in the area. This paper describes the efforts made at UMD in this direction. We present our results on several experiments suggested in FRGC. We believe that though pattern classification techniques play an extremely significant role in automatic face recognition under controlled conditions, physical modeling is required to generalize across varying situations. Accordingly, we describe a generative approach to recognize faces across varying illumination. Unlike most current methods, our method does not ignore shadows. Instead we use them to our benefit by modeling attached shadows in our formulation. JA - Computer Vision and Pattern Recognition - Workshops, 2005. CVPR Workshops. IEEE Computer Society Conference on M3 - 10.1109/CVPR.2005.586 ER - TY - CHAP T1 - Using NMR Spectroscopy to Monitor Ubiquitin Chain Conformation and Interactions with Ubiquitin‐Binding Domains T2 - Ubiquitin and Protein Degradation, Part B Y1 - 2005 A1 - Varadan,Ranjani A1 - Assfalg,Michael A1 - Fushman, David ED - Deshaies,Raymond J. AB - Polyubiquitin (polyUb) chains function as signaling molecules that mediate a diverse set of cellular events. The outcome of polyubiquitination depends on the specific linkage between Ub moieties in the chain, and differently linked chains function as distinct intracellular signals. Although an increasing number of Ub‐binding proteins that transmit the regulatory information conferred by (poly)ubiquitination have been identified, the molecular mechanisms of linkage‐specific signaling and recognition still remain to be understood. Knowledge of the chain structure is expected to provide insights into the basis of diversity in polyUb signaling. Here we describe several NMR approaches aimed at determining the physiological conformation of polyUb and characterization of the chains' interactions with ubiquitin‐binding proteins. JA - Ubiquitin and Protein Degradation, Part B PB - Academic Press VL - Volume 399 SN - 0076-6879 UR - http://www.sciencedirect.com/science/article/pii/S0076687905990125 ER - TY - CHAP T1 - Web Service Composition with Volatile Information T2 - The Semantic Web – ISWC 2005 Y1 - 2005 A1 - Au,Tsz-Chiu A1 - Kuter,Ugur A1 - Nau, Dana S. ED - Gil,Yolanda ED - Motta,Enrico ED - Benjamins,V. ED - Musen,Mark KW - Computer science AB - In many Web service composition problems, information may be needed from Web services during the composition process. Existing research on Web service composition (WSC) procedures has generally assumed that this information will not change. We describe two ways to take such WSC procedures and systematically modify them to deal with volatile information. The black-box approach requires no knowledge of the WSC procedure’s internals: it places a wrapper around the WSC procedure to deal with volatile information. The gray-box approach requires partial information of those internals, in order to insert coding to perform certain bookkeeping operations. We show theoretically that both approaches work correctly. We present experimental results showing that the WSC procedures produced by the gray-box approach can run much faster than the ones produced by the black-box approach. JA - The Semantic Web – ISWC 2005 T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 3729 SN - 978-3-540-29754-3 UR - http://www.springerlink.com/content/y105x8464k54l760/abstract/ ER - TY - JOUR T1 - Weighted coloring based channel assignment for WLANs JF - ACM SIGMOBILE Mobile Computing and Communications Review Y1 - 2005 A1 - Mishra,A. A1 - Banerjee,S. A1 - Arbaugh, William A. VL - 9 CP - 3 ER - TY - CONF T1 - 3D model refinement using surface-parallax T2 - Acoustics, Speech, and Signal Processing, 2004. Proceedings. (ICASSP '04). IEEE International Conference on Y1 - 2004 A1 - Agrawala, Ashok K. A1 - Chellapa, Rama KW - 3D KW - adaptive KW - arbitrary KW - camera KW - coarse KW - compensation; KW - Computer KW - DEM; KW - depth KW - digital KW - ELEVATION KW - environments; KW - epipolar KW - estimation; KW - field; KW - image KW - incomplete KW - INTENSITY KW - map; KW - model KW - MOTION KW - parallax; KW - plane-parallax KW - reconstruction; KW - recovery; KW - refinement; KW - sequence; KW - sequences; KW - surface KW - surfaces; KW - urban KW - vision; KW - windowing; AB - We present an approach to update and refine coarse 3D models of urban environments from a sequence of intensity images using surface parallax. This generalizes the plane-parallax recovery methods to surface-parallax using arbitrary surfaces. A coarse and potentially incomplete depth map of the scene obtained from a digital elevation map (DEM) is used as a reference surface which is refined and updated using this approach. The reference depth map is used to estimate the camera motion and the motion of the 3D points on the reference surface is compensated. The resulting parallax, which is an epipolar field, is estimated using an adaptive windowing technique and used to obtain the refined depth map. JA - Acoustics, Speech, and Signal Processing, 2004. Proceedings. (ICASSP '04). IEEE International Conference on VL - 3 M3 - 10.1109/ICASSP.2004.1326537 ER - TY - CONF T1 - Achieving packet-level quality of service through scheduling in multirate WLANs T2 - Vehicular Technology Conference, 2004. VTC2004-Fall. 2004 IEEE 60th Y1 - 2004 A1 - Yuan Yuan A1 - Daqing Gu A1 - Arbaugh, William A. A1 - Jinyun Zhang KW - Analytical models KW - channel conditions KW - channel errors KW - channel temporal fair share KW - compensation KW - Computer science KW - Delay KW - error-prone flow compensation KW - IEEE 802.11a/b/g physical layer KW - multirate wireless fair scheduling KW - multirate WLAN KW - packet radio networks KW - packet-level quality of service KW - Physical layer KW - Processor scheduling KW - QoS KW - quality of service KW - radio access networks KW - Scheduling algorithm KW - Throughput KW - throughput fairness KW - USA Councils KW - Wireless LAN KW - wireless packet scheduling KW - WMFS AB - Wireless packet scheduling has been a popular paradigm to achieve packet-level QoS in terms of fairness and throughput in the presence of channel errors. However, the current design does not anticipate the multi-rate capability offered by the IEEE 802.11a/b/g physical layer, thus suffering significant performance degradation in 802.11 WLANs. In this paper, we propose multirate wireless fair scheduling (WMFS). In MWFS, each flow is granted a temporal fair share of the channel, in contrast to the throughput fair share adopted by existing algorithms. Therefore, each flow receives services in proportion to its perceived transmission rate, and high-rate flows are able to opportunistically exploit their good channel conditions and receive more services. MWFS also renovates the compensation model in order to allow for error-prone flows to catch up, thus ensuring fairness for all flows over error-prone channels. We demonstrate the effectiveness of MWFS through both simulations and analysis. Especially, WMFS achieves system throughput 159% of state-of-the-art scheduling algorithms in simulated scenarios. JA - Vehicular Technology Conference, 2004. VTC2004-Fall. 2004 IEEE 60th PB - IEEE VL - 4 SN - 0-7803-8521-7 M3 - 10.1109/VETECF.2004.1400554 ER - TY - JOUR T1 - Active deformable models using density estimation JF - International Journal of Image and Graphics Y1 - 2004 A1 - Abd-Almageed, Wael A1 - Smith,C.E. VL - 4 CP - 3 ER - TY - CONF T1 - Active logic for more effective human-computer interaction and other commonsense applications T2 - Proceedings of the Workshop Empirically Successful First-Order Reasoning, International Joint Conference on Automated Reasoning Y1 - 2004 A1 - Anderson,M. L A1 - Josyula,D. A1 - Perlis, Don A1 - Purang,K. JA - Proceedings of the Workshop Empirically Successful First-Order Reasoning, International Joint Conference on Automated Reasoning ER - TY - JOUR T1 - The Argus eye, a new tool for robotics JF - IEEE Robotics and Automation Magazine Y1 - 2004 A1 - Baker, P. A1 - Ogale, A. S A1 - Fermüller, Cornelia A1 - Aloimonos, J. VL - 11 CP - 4 ER - TY - CONF T1 - Challenges in Measuring HPCS Learner Productivity in an Age of Ubiquitous Computing: The HPCS Program T2 - In Proceedings of ICSE Workshop on High Productivity Computing. May 2004 Y1 - 2004 A1 - Asgari, S. A1 - Basili, Victor R. A1 - Carver, J. A1 - Hochstein, L. A1 - Hollingsworth, Jeffrey K A1 - Zelkowitz, Marvin V JA - In Proceedings of ICSE Workshop on High Productivity Computing. May 2004 ER - TY - CONF T1 - A comparison of bug finding tools for Java T2 - Software Reliability Engineering, 2004. ISSRE 2004. 15th International Symposium on Y1 - 2004 A1 - Rutar,N. A1 - Almazan,C.B. A1 - Foster, Jeffrey S. JA - Software Reliability Engineering, 2004. ISSRE 2004. 15th International Symposium on ER - TY - CONF T1 - Compound eye sensor for 3D ego motion estimation T2 - 2004 IEEE/RSJ International Conference on Intelligent Robots and Systems, 2004. (IROS 2004). Proceedings Y1 - 2004 A1 - Neumann, J. A1 - Fermüller, Cornelia A1 - Aloimonos, J. A1 - Brajovic,V. KW - 3D camera motion estimation KW - CAMERAS KW - compound eye vision sensor KW - Computer vision KW - Equations KW - Eyes KW - Geometry KW - Image sensors KW - Insects KW - linear equations KW - Motion estimation KW - robot vision KW - Robustness KW - sampling geometry KW - Sampling methods KW - Sensor phenomena and characterization AB - We describe a compound eye vision sensor for 3D ego motion computation. Inspired by eyes of insects, we show that the compound eye sampling geometry is optimal for 3D camera motion estimation. This optimality allows us to estimate the 3D camera motion in a scene-independent and robust manner by utilizing linear equations. The mathematical model of the new sensor can be implemented in analog networks resulting in a compact computational sensor for instantaneous 3D ego motion measurements in full six degrees of freedom. JA - 2004 IEEE/RSJ International Conference on Intelligent Robots and Systems, 2004. (IROS 2004). Proceedings PB - IEEE VL - 4 SN - 0-7803-8463-6 M3 - 10.1109/IROS.2004.1389992 ER - TY - CONF T1 - Copilot - a coprocessor-based kernel runtime integrity monitor T2 - Proceedings of the 13th conference on USENIX Security Symposium - Volume 13 Y1 - 2004 A1 - Petroni,Jr. A1 - Fraser,Timothy A1 - Molina,Jesus A1 - Arbaugh, William A. KW - design KW - management KW - MONITORS KW - Security KW - security and protection AB - Copilot is a coprocessor-based kernel integrity monitor for commodity systems. Copilot is designed to detect malicious modifications to a host's kernel and has correctly detected the presence of 12 real-world rootkits, each within 30 seconds of their installation with less than a 1% penalty to the host's performance. Copilot requires no modifications to the protected host's software and can be expected to operate correctly even when the host kernel is thoroughly compromised - an advantage over traditional monitors designed to run on the host itself. JA - Proceedings of the 13th conference on USENIX Security Symposium - Volume 13 T3 - SSYM'04 PB - USENIX Association CY - San Diego, CA UR - http://portal.acm.org/citation.cfm?id=1251375.1251388 ER - TY - CONF T1 - Divergence Unraveling for Word Alignment... T2 - Natural Language Engineering Y1 - 2004 A1 - Dorr, Bonnie J A1 - Ayan,N.F. A1 - Habash,N. AB - We describe the use of parallel text for divergence unraveling in word-level alignment. DUSTer (Divergence Unraveling for Statistical Translation) is a system that combines linguistic and statistical knowledge to resolve structural di#erences between languages, i.e., translation divergences, during the process of alignment. Our immediate goal is to induce word-level alignments that are more accurate than those produced by an existing state-ofthe -art statistical system. The long-term goal is to improve the output quality of statistical machine translation and lexical acquisition systems by using DUSTer as one possible input to a framework that accommodates multiple alignments. We show that a systematic characterization of alignment errors made by a statistical system validates the use of linguistically-motivated universal rules for identifying and handling divergences. These rules relate one or more linguistically-motivated categories associated with the (English) input words to those of another language (foreign language); the resulting match sets are used to infer corrected alignments. Using a human-aligned corpus as our gold standard, we demonstrate an improvement in alignments over an existing state-of-the-art alignment algorithm. JA - Natural Language Engineering ER - TY - CONF T1 - Domain-independent reason-enhanced controller for task-oriented systems-DIRECTOR T2 - PROCEEDINGS OF THE NATIONAL CONFERENCE ON ARTIFICIAL IN℡LIGENCE Y1 - 2004 A1 - Josyula,D. P A1 - Anderson,M. L A1 - Perlis, Don JA - PROCEEDINGS OF THE NATIONAL CONFERENCE ON ARTIFICIAL IN℡LIGENCE ER - TY - JOUR T1 - Efficient Execution of Multi-Query Data Analysis Batches Using Compiler Optimization Strategies JF - Languages and Compilers for Parallel Computing Y1 - 2004 A1 - Andrade,H. A1 - Aryangat,S. A1 - Kurc, T. A1 - Saltz, J. A1 - Sussman, Alan AB - This work investigates the leverage that can be obtained from compiler optimization techniques for efficient execution of multi-query workloads in data analysis applications. Our approach is to address multi-query optimization at the algorithmic level, by transforming a declarative specification of scientific data analysis queries into a high-level imperative program that can be made more efficient by applying compiler optimization techniques. These techniques – including loop fusion, common subexpression elimination and dead code elimination – are employed to allow data and computation reuse across queries. We describe a preliminary experimental analysis on a real remote sensing application that analyzes very large quantities of satellite data. The results show our techniques achieve sizable reductions in the amount of computation and I/O necessary for executing query batches and in average execution times for the individual queries in a given batch. M3 - 10.1007/978-3-540-24644-2_33 ER - TY - CONF T1 - Empirical-based estimation of the effect on software dependability of a technique for architecture conformance verification T2 - Proceedings of the ICSE 2004 Workshop on Architecting Dependable Systems, Edinburgh, UK Y1 - 2004 A1 - Asgari, S. A1 - Basili, Victor R. A1 - Costa,P. A1 - Donzelli,P. A1 - Hochstein, L. A1 - Lindvall,M. A1 - Rus,I. A1 - Shull, F. A1 - Tvedt,R. A1 - Zelkowitz, Marvin V AB - The High Dependability Computing Program (HDCP)project is a NASA initiative for increasing dependability of software-based systems. It researches achieving high dependability by introducing new technologies. We focus on the evaluation of the effectiveness of technologies with respect to dependability. We employ empirical evaluation methods along with evaluation testbeds. In this paper, our technology evaluation approach is described. A testbed representative of air traffic control applications is used. An experiment to evaluate a technology to for identification of architectural violations is presented. JA - Proceedings of the ICSE 2004 Workshop on Architecting Dependable Systems, Edinburgh, UK ER - TY - CONF T1 - Ferret: a host vulnerability checking tool Y1 - 2004 A1 - Sharma,Anil A1 - Martin,J.R. A1 - Anand,N. A1 - Michel Cukier A1 - Sanders,W. H. KW - Ferret software tool KW - host vulnerability checking tool KW - open-source software KW - Perl KW - plug-in module KW - program verification KW - security auditing tool KW - security evaluation KW - security of data KW - software tools AB - Evaluation of computing system security requires knowledge of the vulnerabilities present in the system and of potential attacks against the system. Vulnerabilities can be classified based on their location as application vulnerabilities, network vulnerabilities, or host vulnerabilities. We describe Ferret, a new software tool for checking host vulnerabilities. Ferret helps system administrators by quickly finding vulnerabilities that are present on a host. It is designed and implemented in a modular way: a different plug-in module is used for each vulnerability checked, and each possible output format is specified by a plug-in module. As a result, Ferret is extensible, and can easily be kept up-to-date through addition of checks for new vulnerabilities as they are discovered; the modular approach also makes it easy to provide specific configurations of Ferret tailored to specific operating systems or use environments. Ferret is a freely available open-source software implemented in Perl. M3 - 10.1109/PRDC.2004.1276595 ER - TY - JOUR T1 - A hierarchy of cameras for 3D photography JF - Computer Vision and Image Understanding Y1 - 2004 A1 - Neumann, Jan A1 - Fermüller, Cornelia A1 - Aloimonos, J. KW - Camera design KW - Multi-view geometry KW - Polydioptric cameras KW - Spatio-temporal image analysis KW - structure from motion AB - The view-independent visualization of 3D scenes is most often based on rendering accurate 3D models or utilizes image-based rendering techniques. To compute the 3D structure of a scene from a moving vision sensor or to use image-based rendering approaches, we need to be able to estimate the motion of the sensor from the recorded image information with high accuracy, a problem that has been well-studied. In this work, we investigate the relationship between camera design and our ability to perform accurate 3D photography, by examining the influence of camera design on the estimation of the motion and structure of a scene from video data. By relating the differential structure of the time varying plenoptic function to different known and new camera designs, we can establish a hierarchy of cameras based upon the stability and complexity of the computations necessary to estimate structure and motion. At the low end of this hierarchy is the standard planar pinhole camera for which the structure from motion problem is non-linear and ill-posed. At the high end is a camera, which we call the full field of view polydioptric camera, for which the motion estimation problem can be solved independently of the depth of the scene which leads to fast and robust algorithms for 3D Photography. In between are multiple view cameras with a large field of view which we have built, as well as omni-directional sensors. VL - 96 SN - 1077-3142 UR - http://www.sciencedirect.com/science/article/pii/S1077314204000505 CP - 3 M3 - 10.1016/j.cviu.2004.03.013 ER - TY - CONF T1 - High-performance MAC for high-capacity wireless LANs T2 - 13th International Conference on Computer Communications and Networks, 2004. ICCCN 2004. Proceedings Y1 - 2004 A1 - Yuan Yuan A1 - Daqing Gu A1 - Arbaugh, William A. A1 - Jinyun Zhang KW - 35 Mbit/s KW - access protocols KW - Aggregates KW - Bandwidth KW - batch transmission KW - Computer science KW - Educational institutions KW - high-capacity wireless LAN KW - high-performance MAC KW - Laboratories KW - Local area networks KW - Media Access Protocol KW - opportunistic selection KW - Physical layer KW - probability KW - Throughput KW - Wireless LAN AB - The next-generation wireless technologies, e.g., 802.11n and 802.15.3a, offer a physical-layer speed at least an-order-of-magnitude higher than the current standards. However, direct application of current MACs leads to high protocol overhead and significant throughput degradation. In this paper, we propose ADCA, a high-performance MAC that works with high-capacity physical layer. ADCA exploits two ideas of adaptive batch transmission and opportunistic selection of high-rate hosts to simultaneously reduce the overhead and improve the aggregate throughput. It opportunistically favors high-rate hosts by providing higher access probability and more access time, while ensuring each low-rate host certain minimum amount of channel access time. Simulations show that the ADCA design increases the throughput by 112% and reduces the average delay by 55% compared with the legacy DCF. It delivers more than 100 Mbps MAC-layer throughput as compared with 35 Mbps offered by the legacy MAC JA - 13th International Conference on Computer Communications and Networks, 2004. ICCCN 2004. Proceedings PB - IEEE SN - 0-7803-8814-3 M3 - 10.1109/ICCCN.2004.1401615 ER - TY - CONF T1 - The influence of shape on image correspondence T2 - 2nd International Symposium on 3D Data Processing, Visualization and Transmission, 2004. 3DPVT 2004. Proceedings Y1 - 2004 A1 - Ogale, A. S A1 - Aloimonos, J. KW - Automation KW - CAMERAS KW - Computational modeling KW - first order approximation KW - Geometrical optics KW - hidden feature removal KW - image sampling KW - Image segmentation KW - Layout KW - occlusion detection KW - piecewise continuous function KW - Pixel KW - SHAPE KW - Simulated annealing KW - stereo image processing KW - surface fitting AB - We examine the implications of shape on the process of finding dense correspondence and half-occlusions for a stereo pair of images. The desired property of the depth map is that it should be a piecewise continuous function which is consistent with the images and which has the minimum number of discontinuities. To zeroeth order, piecewise continuity becomes piecewise constancy. Using this approximation, we first discuss an approach for dealing with such a fronto-parallel shapeless world, and the problems involved therein. We then introduce horizontal and vertical slant to create a first order approximation to piecewise continuity. We highlight the fact that a horizontally slanted surface (ie. having depth variation in the direction of the separation of the two cameras) appears horizontally stretched in one image as compared to the other image. Thus, while corresponding two images, N pixels on a scanline in one image may correspond to a different number of pixels M in the other image, which has consequences with regard to sampling and occlusion detection. We also discuss the asymmetry between vertical and horizontal slant, and the central role of nonhorizontal edges in the context of vertical slant. Using experiments, we discuss cases where existing algorithms fail, and how the incorporation of new constraints provides correct results. JA - 2nd International Symposium on 3D Data Processing, Visualization and Transmission, 2004. 3DPVT 2004. Proceedings PB - IEEE SN - 0-7695-2223-8 M3 - 10.1109/TDPVT.2004.1335418 ER - TY - PAT T1 - Method of designing signaling networks for internet telephony Y1 - 2004 A1 - Aravamudan,Murali A1 - Kumaran,Krishnan A1 - Ramakrishnan,Kajamalai Gopalaswamy A1 - Srinivasan, Aravind ED - Lucent Technologies Inc. AB - A method is disclosed for designing a signaling network of call coordinators (CCs) for internet telephony. The new method can be used to design a CC network of arbitrary size that satisfies, with high probability, limitations on the maximum number of sockets per CC and on the maximum number of hops between an arbitrary pair of switches in the network. According to the disclosed method, the network of CCs is treated initially as a collection of isolated points, one point for each CC. Then, links are added between pairs of CCs, excluding pairs lying within the same switch. The links are added randomly, but with a particular probability p, which may be different for different pairs. Thus, whether a given link is added depends, in effect, upon the outcome of a loaded coin toss in which the probability of a positive outcome is p. VL - : 09/517,658 UR - http://www.google.com/patents?id=VTsSAAAAEBAJ CP - 6687363 ER - TY - CHAP T1 - Multi-align: Combining Linguistic and Statistical Techniques to Improve Alignments for Adaptable MT T2 - Machine Translation: From Real Users to ResearchMachine Translation: From Real Users to Research Y1 - 2004 A1 - Ayan,Necip A1 - Dorr, Bonnie J A1 - Habash,Nizar ED - Frederking,Robert ED - Taylor,Kathryn AB - An adaptable statistical or hybrid MT system relies heavily on the quality of word-level alignments of real-world data. Statistical alignment approaches provide a reasonable initial estimate for word alignment. However, they cannot handle certain types of linguistic phenomena such as long-distance dependencies and structural differences between languages. We address this issue in Multi-Align, a new framework for incremental testing of different alignment algorithms and their combinations. Our design allows users to tune their systems to the properties of a particular genre/domain while still benefiting from general linguistic knowledge associated with a language pair. We demonstrate that a combination of statistical and linguistically-informed alignments can resolve translation divergences during the alignment process. JA - Machine Translation: From Real Users to ResearchMachine Translation: From Real Users to Research T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 3265 SN - 978-3-540-23300-8 UR - http://dx.doi.org/10.1007/978-3-540-30194-3_3 ER - TY - CHAP T1 - Plan Databases: Model and Algebra T2 - Foundations of Information and Knowledge Systems Y1 - 2004 A1 - Yaman,Fusun A1 - Adali,Sibel A1 - Nau, Dana S. A1 - Sapino,Maria A1 - Subrahmanian,V. ED - Seipel,Dietmar ED - Turull-Torres,José KW - Computer science AB - Despite the fact that thousands of applications manipulate plans, there has been no work to date on managing large databases of plans. In this paper, we first propose a formal model of plan databases. We describe important notions of consistency and coherence for such databases. We then propose a set of operators similar to the relational algebra to query such databases of plans. JA - Foundations of Information and Knowledge Systems T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 2942 SN - 978-3-540-20965-2 UR - http://www.springerlink.com/content/yqhlqtu4te18q2e1/abstract/ ER - TY - CONF T1 - The priority curve algorithm for video summarization T2 - Proceedings of the 2nd ACM international workshop on Multimedia databases Y1 - 2004 A1 - Fayzullin,M. A1 - V.S. Subrahmanian A1 - Albanese, M. A1 - Picariello, A. KW - probabilistic KW - Summarization KW - system KW - video AB - In this paper, we introduce the concept of a priority curve associated with a video. We then provide an algorithm that can use the priority curve to create a summary (of a desired length) of any video. The summary thus created exhibits nice continuity properties and also avoids repetition. We have implemented the priority curve algorithm (PCA) and compared it with other summarization algorithms in the literature. We show that PCA is faster than existing algorithms and also produces better quality summaries. The quality of summaries was evaluated by a group of 200 students in Naples, Italy, who watched soccer videos. We also briefly describe a soccer video summarization system we have built on using the PCA architecture and various (classical) image processing algorithms. JA - Proceedings of the 2nd ACM international workshop on Multimedia databases T3 - MMDB '04 PB - ACM CY - New York, NY, USA SN - 1-58113-975-6 UR - http://doi.acm.org/10.1145/1032604.1032611 M3 - 10.1145/1032604.1032611 ER - TY - JOUR T1 - Proactive key distribution using neighbor graphs JF - IEEE Wireless Communications Y1 - 2004 A1 - Mishra,A. A1 - Min Ho Shin A1 - Petroni,N. L. A1 - Clancy,T. C A1 - Arbaugh, William A. KW - access points KW - Authentication KW - authentication time KW - Base stations KW - Communication system security KW - Delay KW - graph theory KW - GSM KW - IEEE 802.11 handoff KW - Land mobile radio cellular systems KW - Message authentication KW - mobile radio KW - Multiaccess communication KW - neighbor graph KW - Network topology KW - Roaming KW - telecommunication security KW - Telephone sets KW - user mobility KW - Wi-Fi networks KW - wireless data networks KW - Wireless LAN KW - Wireless networks AB - User mobility in wireless data networks is increasing because of technological advances, and the desire for voice and multimedia applications. These applications, however, require that handoffs between base stations (or access points) be fast to maintain the quality of the connections. In this article we introduce a novel data structure, the neighbor graph, that dynamically captures the mobility topology of a wireless network. We show how neighbor graphs can be utilized to obtain a 99 percent reduction in the authentication time of an IEEE 802.11 handoff (full EAP-TLS) by proactively distributing necessary key material one hop ahead of the mobile user. We also present a reactive method for fast authentication that requires only firmware changes to access points and hence can easily be deployed on existing wireless networks. VL - 11 SN - 1536-1284 CP - 1 M3 - 10.1109/MWC.2004.1269714 ER - TY - JOUR T1 - Robotics & Automation Magazine Vol. 11 JF - IEEE Robotics & Automation Magazine Y1 - 2004 A1 - Aliaga, D.G. A1 - Allen,PK A1 - Archibald,JK A1 - Argyros,AA A1 - Arkin,RC A1 - Baker,C. A1 - Baker, P. A1 - Beard,RW A1 - Bicchi,A. A1 - Birgmajer,B. A1 - others ER - TY - CONF T1 - Robust ego-motion estimation and 3D model refinement using depth based parallax model T2 - Image Processing, 2004. ICIP '04. 2004 International Conference on Y1 - 2004 A1 - Agrawala, Ashok K. A1 - Chellapa, Rama KW - 3D KW - algorithm; KW - analysis; KW - and KW - based KW - camera; KW - coarse KW - compensation; KW - DEM; KW - depth KW - digital KW - ego-motion KW - eigen-value KW - eigenfunctions; KW - eigenvalues KW - ELEVATION KW - epipolar KW - estimation; KW - extraction; KW - feature KW - field; KW - iteration KW - iterative KW - map; KW - method; KW - methods; KW - model KW - model; KW - MOTION KW - parallax KW - partial KW - range-finding; KW - refinement; KW - refining; KW - surface AB - We present an iterative algorithm for robustly estimating the ego-motion and refining and updating a coarse, noisy and partial depth map using a depth based parallax model and brightness derivatives extracted from an image pair. Given a coarse, noisy and partial depth map acquired by a range-finder or obtained from a Digital Elevation Map (DFM), we first estimate the ego-motion by combining a global ego-motion constraint and a local brightness constancy constraint. Using the estimated camera motion and the available depth map estimate, motion of the 3D points is compensated. We utilize the fact that the resulting surface parallax field is an epipolar field and knowing its direction from the previous motion estimates, estimate its magnitude and use it to refine the depth map estimate. Instead of assuming a smooth parallax field or locally smooth depth models, we locally model the parallax magnitude using the depth map, formulate the problem as a generalized eigen-value analysis and obtain better results. In addition, confidence measures for depth estimates are provided which can be used to remove regions with potentially incorrect (and outliers in) depth estimates for robustly estimating ego-motion in the next iteration. Results on both synthetic and real examples are presented. JA - Image Processing, 2004. ICIP '04. 2004 International Conference on VL - 4 M3 - 10.1109/ICIP.2004.1421606 ER - TY - JOUR T1 - Security issues in IEEE 802.11 wireless local area networks: a survey JF - Wireless Communications and Mobile Computing Y1 - 2004 A1 - Mishra,A. A1 - Petroni Jr,N. L A1 - Arbaugh, William A. A1 - Fraser,T. VL - 4 CP - 8 ER - TY - JOUR T1 - Solution Conformation of Lys63-linked Di-ubiquitin Chain Provides Clues to Functional Diversity of Polyubiquitin Signaling JF - Journal of Biological ChemistryJ. Biol. Chem. Y1 - 2004 A1 - Varadan,Ranjani A1 - Assfalg,Michael A1 - Haririnia,Aydin A1 - Raasi,Shahri A1 - Pickart,Cecile A1 - Fushman, David AB - Diverse cellular events are regulated by post-translational modification of substrate proteins via covalent attachment of one or a chain of ubiquitin molecules. The outcome of (poly)ubiquitination depends upon the specific lysine residues involved in the formation of polyubiquitin chains. Lys48-linked chains act as a universal signal for proteasomal degradation, whereas Lys63-linked chains act as a specific signal in several non-degradative processes. Although it has been anticipated that functional diversity between alternatively linked polyubiquitin chains relies on linkage-dependent differences in chain conformation/topology, direct structural evidence in support of this model has been lacking. Here we use NMR methods to determine the structure of a Lys63-linked di-ubiquitin chain. The structure is characterized by an extended conformation, with no direct contact between the hydrophobic residues Leu8, Ile44, and Val70 on the ubiquitin units. This structure contrasts with the closed conformation observed for Lys48-linked di-ubiquitin wherein these residues form the interdomain interface (Cook, W. J., Jeffrey, L. C., Carson, M., Zhijian, C., and Pickart, C. M. (1992) J. Biol. Chem. 267, 16467-16471; Varadan, R., Walker, O., Pickart, C., and Fushman, D. (2002) J. Mol. Biol. 324, 637-647). Consistent with the open conformation of the Lys63-linked di-ubiquitin, our binding studies show that both ubiquitin domains in this chain can bind a ubiquitin-associated domain from HHR23A independently and in a mode similar to that for mono-ubiquitin. In contrast, Lys48-linked di-ubiquitin binds in a different, higher affinity mode that has yet to be determined. This is the first experimental evidence that alternatively linked polyubiquitin chains adopt distinct conformations. VL - 279 SN - 0021-9258, 1083-351X UR - http://www.jbc.org/content/279/8/7055 CP - 8 M3 - 10.1074/jbc.M309184200 ER - TY - CONF T1 - Stereo Correspondence with Slanted Surfaces: Critical Implications of Horizontal Slant T2 - Computer Vision and Pattern Recognition, IEEE Computer Society Conference on Y1 - 2004 A1 - Ogale, Abhijit S. A1 - Aloimonos, J. AB - We examine the stereo correspondence problem in the presence of slanted scene surfaces. In particular, we highlight a previously overlooked geometric fact: a horizontally slanted surface (i.e. having depth variation in the direction of the separation of the two cameras) will appear horizontally stretched in one image as compared to the other image. Thus, while corresponding two images, N pixels on a scanline in one image may correspond to a different number of pixels M in the other image. This leads to three important modifications to existing stereo algorithms: (a) due to unequal sampling, intensity matching metrics such as the popular Birchfield-Tomasi procedure must be modified, (b) unequal numbers of pixels in the two images must be allowed to correspond to each other, and (c) the uniqueness constraint, which is often used for detecting occlusions, must be changed to a 3D uniqueness constraint. This paper discusses these new constraints and provides a simple scanline based matching algorithm for illustration. We experimentally demonstrate test cases where existing algorithms fail, and how the incorporation of these new constraints provides correct results. Experimental comparisons of the scanline based algorithm with standard data sets are also provided. JA - Computer Vision and Pattern Recognition, IEEE Computer Society Conference on PB - IEEE Computer Society CY - Los Alamitos, CA, USA VL - 1 M3 - http://doi.ieeecomputersociety.org/10.1109/CVPR.2004.241 ER - TY - JOUR T1 - Structure from motion of parallel lines JF - Computer Vision-ECCV 2004 Y1 - 2004 A1 - Baker, P. A1 - Aloimonos, J. ER - TY - CONF T1 - Studying code development for high performance computing: the HPCS program T2 - First International Workshop On Software Engineering for High Performance Computing System Applications Y1 - 2004 A1 - Carver, J. A1 - Asgari, S. A1 - Basili, Victor R. A1 - Hochstein, L. A1 - Hollingsworth, Jeffrey K A1 - Shull, F. A1 - Zelkowitz, Marvin V JA - First International Workshop On Software Engineering for High Performance Computing System Applications ER - TY - CONF T1 - A system identification approach for video-based face recognition T2 - Pattern Recognition, 2004. ICPR 2004. Proceedings of the 17th International Conference on Y1 - 2004 A1 - Aggarwal,G. A1 - Chowdhury, A.K.R. A1 - Chellapa, Rama KW - and KW - autoregressive KW - average KW - dynamical KW - Face KW - gallery KW - identification; KW - image KW - linear KW - model; KW - moving KW - processes; KW - processing; KW - recognition; KW - sequences; KW - signal KW - system KW - system; KW - video KW - video-based AB - The paper poses video-to-video face recognition as a dynamical system identification and classification problem. We model a moving face as a linear dynamical system whose appearance changes with pose. An autoregressive and moving average (ARMA) model is used to represent such a system. The choice of ARMA model is based on its ability to take care of the change in appearance while modeling the dynamics of pose, expression etc. Recognition is performed using the concept of sub space angles to compute distances between probe and gallery video sequences. The results obtained are very promising given the extent of pose, expression and illumination variation in the video data used for experiments. JA - Pattern Recognition, 2004. ICPR 2004. Proceedings of the 17th International Conference on VL - 4 M3 - 10.1109/ICPR.2004.1333732 ER - TY - CONF T1 - Time and space optimization for processing groups of multi-dimensional scientific queries T2 - Proceedings of the 18th annual international conference on Supercomputing Y1 - 2004 A1 - Aryangat,Suresh A1 - Andrade,Henrique A1 - Sussman, Alan KW - multi-query optimization KW - Scientific databases AB - Data analysis applications in areas as diverse as remote sensing and telepathology require operating on and processing very large datasets. For such applications to execute efficiently, careful attention must be paid to the storage, retrieval, and manipulation of the datasets. This paper addresses the optimizations performed by a high performance database system that processes groups of data analysis requests for these applications, which we call queries. The system performs end-to-end processing of the requests, formulated as PostgreSQL declarative queries. The queries are converted into imperative descriptions, multiple imperative descriptions are merged into a single execution plan, the plan is optimized to decrease execution time via common compiler optimization techniques, and, finally, the plan is optimized to decrease memory consumption. The last two steps are experimentally shown to effectively reduc the amount of time required while conserving memory space as a group of queries is processed by the database. JA - Proceedings of the 18th annual international conference on Supercomputing T3 - ICS '04 PB - ACM CY - New York, NY, USA SN - 1-58113-839-3 UR - http://doi.acm.org/10.1145/1006209.1006224 M3 - 10.1145/1006209.1006224 ER - TY - CONF T1 - Utilizing volatile external information during planning T2 - Proceedings of the European Conference on Artificial Intelligence (ECAI) Y1 - 2004 A1 - Au,T. C A1 - Nau, Dana S. A1 - V.S. Subrahmanian JA - Proceedings of the European Conference on Artificial Intelligence (ECAI) ER - TY - JOUR T1 - Viable but Nonculturable Vibrio Cholerae O1 in the Aquatic Environment of Argentina JF - Applied and Environmental MicrobiologyAppl. Environ. Microbiol. Y1 - 2004 A1 - Binsztein,Norma A1 - Costagliola,Marcela C. A1 - Pichel,Mariana A1 - Jurquiza,Verónica A1 - Ramírez,Fernando C. A1 - Akselman,Rut A1 - Vacchino,Marta A1 - Huq,Anwarul A1 - Rita R Colwell AB - In Argentina, as in other countries of Latin America, cholera has occurred in an epidemic pattern. Vibrio cholerae O1 is native to the aquatic environment, and it occurs in both culturable and viable but nonculturable (VNC) forms, the latter during interepidemic periods. This is the first report of the presence of VNC V. cholerae O1 in the estuarine and marine waters of the Río de la Plata and the Argentine shelf of the Atlantic Ocean, respectively. Employing immunofluorescence and PCR methods, we were able to detect reservoirs of V. cholerae O1 carrying the virulence-associated genes ctxA and tcpA. The VNC forms of V. cholerae O1 were identified in samples of water, phytoplankton, and zooplankton; the latter organisms were mainly the copepods Acartia tonsa, Diaptomus sp., Paracalanus crassirostris, and Paracalanus parvus. We found that under favorable conditions, the VNC form of V. cholerae can revert to the pathogenic, transmissible state. We concluded that V. cholerae O1 is a resident of Argentinean waters, as has been shown to be the case in other geographic regions of the world. VL - 70 SN - 0099-2240, 1098-5336 UR - http://aem.asm.org/content/70/12/7481 CP - 12 M3 - 10.1128/AEM.70.12.7481-7486.2004 ER - TY - CONF T1 - Window-based, discontinuity preserving stereo T2 - Computer Vision and Pattern Recognition, 2004. CVPR 2004. Proceedings of the 2004 IEEE Computer Society Conference on Y1 - 2004 A1 - Agrawal,M. A1 - Davis, Larry S. KW - algorithm; KW - approach; KW - based KW - cuts; KW - dense KW - discontinuity KW - global KW - graph KW - image KW - local KW - MATCHING KW - matching; KW - minimisation; KW - optimization; KW - Pixel KW - preserving KW - processing; KW - stereo KW - theory; KW - window AB - Traditionally, the problem of stereo matching has been addressed either by a local window-based approach or a dense pixel-based approach using global optimization. In this paper we present an algorithm which combines window-based local matching into a global optimization framework. Our local matching algorithm assumes that local windows can have at most two disparities. Under this assumption, the local matching can be performed very efficiently using graph cuts. The global matching is formulated as minimization of an energy term that takes into account the matching constraints induced by the local stereo algorithm. Fast, approximate minimization of this energy is achieved through graph cuts. The key feature of our algorithm is that it preserves discontinuities both during the local as well as global matching phase. JA - Computer Vision and Pattern Recognition, 2004. CVPR 2004. Proceedings of the 2004 IEEE Computer Society Conference on VL - 1 M3 - 10.1109/CVPR.2004.1315015 ER - TY - JOUR T1 - 2003 IEEE Workshop on Applications of Signal Processing to Audio and Acoustics October 19-22, 2003, New Paltz. NY JF - 2003 IEEE Workshop on Applications of Signal Processing to Audio and Acoustics: October 19-22, 2003, Mohonk Mountain House, New Paltz, NY, USA Y1 - 2003 A1 - Adams,N. A1 - EssI,G. A1 - Makino,S. A1 - Martens,A.A.C.F.W.L. A1 - Algazi,R. A1 - Fellers,M. A1 - Martin,R. A1 - Avendano,C. A1 - Fielder,L. A1 - Mellody,M. A1 - others ER - TY - JOUR T1 - A 4-Year Study of the Epidemiology of Vibrio Cholerae in Four Rural Areas of Bangladesh JF - Journal of Infectious DiseasesJ Infect Dis. Y1 - 2003 A1 - Sack,R. Bradley A1 - Siddique,A. Kasem A1 - Longini,Ira M. A1 - Nizam,Azhar A1 - Yunus,Md A1 - M. Sirajul Islam A1 - Morris,Jr A1 - Ali,Afsar A1 - Huq,Anwar A1 - Nair,G. Balakrish A1 - Qadri,Firdausi A1 - Faruque,Shah M. A1 - Sack,David A. A1 - Rita R Colwell AB - How Vibrio cholerae spreads around the world and what determines its seasonal peaks in endemic areas are not known. These features of cholera have been hypothesized to be primarily the result of environmental factors associated with aquatic habitats that can now be identified. Since 1997, fortnightly surveillance in 4 widely separated geographic locations in Bangladesh has been performed to identify patients with cholera and to collect environmental data. A total of 5670 patients (53% <5 years of age) have been studied; 14.3% had cholera (10.4% due to V. cholerae O1 El Tor, 3.8% due to O139). Both serogroups were found in all locations; outbreaks were seasonal and often occurred simultaneously. Water-use patterns showed that bathing and washing clothes in tube-well water was significantly protective in two of the sites. These data will be correlated with environmental factors, to develop a model for prediction of cholera outbreaks VL - 187 SN - 0022-1899, 1537-6613 UR - http://jid.oxfordjournals.org/content/187/1/96 CP - 1 M3 - 10.1086/345865 ER - TY - JOUR T1 - An Analysis of the Layer 2 Handoff costs in Wireless Local Area Networks JF - ACM Computer Communications Review Y1 - 2003 A1 - Mishra,A. A1 - Shin,M. H. A1 - Arbaugh, William A. VL - 33 CP - 2 ER - TY - CHAP T1 - Approximation Algorithms for Channel Allocation Problems in Broadcast Networks T2 - Approximation, Randomization, and Combinatorial Optimization: Algorithms and Techniques Y1 - 2003 A1 - Gandhi,Rajiv A1 - Khuller, Samir A1 - Srinivasan, Aravind A1 - Wang,Nan ED - Arora,Sanjeev ED - Jansen,Klaus ED - Rolim,José ED - Sahai,Amit AB - We study two packing problems that arise in the area of dissemination-based information systems; a second theme is the study of distributed approximation algorithms. The problems considered have the property that the space occupied by a collection of objects together could be significantly less than the sum of the sizes of the individual objects. In the Channel Allocation Problem , there are users who request subsets of items. There are a fixed number of channels that can carry an arbitrary amount of information. Each user must get all of the requested items from one channel, i.e., all the data items of each request must be broadcast on some channel. The load on any channel is the number of items that are broadcast on that channel; the objective is to minimize the maximum load on any channel. We present approximation algorithms for this problem and also show that the problem is MAX-SNP hard. The second problem is the Edge Partitioning Problem addressed by Goldschmidt, Hochbaum, Levin, and Olinick ( Networks, 41:13-23, 2003 ). Each channel here can deliver information to at most k users, and we aim to minimize the total load on all channels. We present an O ( n⅓ )–approximation algorithm and also show that the algorithm can be made fully distributed with the same approximation guarantee; we also generalize to the case of hypergraphs. JA - Approximation, Randomization, and Combinatorial Optimization: Algorithms and Techniques T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 2764 SN - 978-3-540-40770-6 UR - http://dx.doi.org/10.1007/978-3-540-45198-3_5 ER - TY - CONF T1 - Bootstrapping security associations for routing in mobile ad-hoc networks T2 - IEEE Global Telecommunications Conference, 2003. GLOBECOM '03 Y1 - 2003 A1 - Bobba,R. B A1 - Eschenauer,L. A1 - Gligor,V. A1 - Arbaugh, William A. KW - ad hoc networks KW - bootstrapping security association KW - Cryptographic protocols KW - dynamic source routing protocol KW - Fabrics KW - Intelligent networks KW - IP address KW - IP key KW - IP networks KW - Message authentication KW - mobile ad-hoc network KW - mobile radio KW - Protection KW - Public key KW - public key cryptography KW - routing layer security reliability KW - routing protocols KW - secure routing KW - Security KW - security service KW - statistically unique cryptographically verification KW - telecommunication security AB - To date, most solutions proposed for secure routing in mobile ad-hoc networks (MANETs), assume that secure associations between pairs of nodes can be established on-line; e.g., by a trusted third party, by distributed trust establishment. However, establishing such security associations, with or without trusted third parties, requires reliance on routing layer security. In this paper, we eliminate this apparent cyclic dependency between security services and secure routing in MANETs and show how to bootstrap security for the routing layer. We use the notion of statistically unique and cryptographically verifiable (SUCV) identifiers to implement a secure binding between IP addresses and keys that is independent of any trusted security service. We illustrate our solution with the dynamic source routing (DSR) protocol and compare it with other solutions for secure routing. JA - IEEE Global Telecommunications Conference, 2003. GLOBECOM '03 PB - IEEE VL - 3 SN - 0-7803-7974-8 M3 - 10.1109/GLOCOM.2003.1258490 ER - TY - CONF T1 - Camera calibration using spheres: a semi-definite programming approach T2 - Computer Vision, 2003. Proceedings. Ninth IEEE International Conference on Y1 - 2003 A1 - Agrawal,M. A1 - Davis, Larry S. KW - 3D KW - algorithms;calibration;cameras;computer KW - approach;sphere KW - calibration;camera KW - contours;semidefinite KW - extraction; KW - field;ellipse;intrinsic KW - location;spheres;vision KW - networks;common KW - parameters;occluding KW - Programming KW - target;camera KW - view KW - vision;feature AB - Vision algorithms utilizing camera networks with a common field of view are becoming increasingly feasible and important. Calibration of such camera networks is a challenging and cumbersome task. The current approaches for calibration using planes or a known 3D target may not be feasible as these objects may not be simultaneously visible in all the cameras. In this paper, we present a new algorithm to calibrate cameras using occluding contours of spheres. In general, an occluding contour of a sphere projects to an ellipse in the image. Our algorithm uses the projection of the occluding contours of three spheres and solves for the intrinsic parameters and the locations of the spheres. The problem is formulated in the dual space and the parameters are solved for optimally and efficiently using semidefinite programming. The technique is flexible, accurate and easy to use. In addition, since the contour of a sphere is simultaneously visible in all the cameras, our approach can greatly simplify calibration of multiple cameras with a common field of view. Experimental results from computer simulated data and real world data, both for a single camera and multiple cameras, are presented. JA - Computer Vision, 2003. Proceedings. Ninth IEEE International Conference on M3 - 10.1109/ICCV.2003.1238428 ER - TY - CONF T1 - Checking and inferring local non-aliasing T2 - ACM SIGPLAN Notices Y1 - 2003 A1 - Aiken,A. A1 - Foster, Jeffrey S. A1 - Kodumal,J. A1 - Terauchi,T. JA - ACM SIGPLAN Notices VL - 38 ER - TY - JOUR T1 - Complete camera calibration using spheres: Dual space approach JF - IEEE Y1 - 2003 A1 - Agrawal,M. A1 - Davis, Larry S. AB - Camera calibration is a fundamental problem in computer vision and photogrammetry. We present a new algorithmto calibrate cameras using spheres. In general, an occluding contour of a sphere projects to an ellipse in the image. Our algorithm uses the projection of the occluding contours of three spheres and solves for the intrinsic parameters and the locations of the spheres. The problem is formulated in the dual space and the parameters are solved for optimally and efficiently using semi-definite programming. The technique is flexible, accurate and easy to use. In addition, it can be used to simultaneously calibrate multiple cameras with a common field of view. Experimen- tal results from computer simulated data and real world data, both for a single camera and multiple cameras, are presented. VL - 206 ER - TY - JOUR T1 - Computational video JF - The Visual Computer Y1 - 2003 A1 - Aloimonos, J. VL - 19 CP - 6 ER - TY - JOUR T1 - The dangers of mitigating security design flaws: a wireless case study JF - IEEE Security & Privacy Y1 - 2003 A1 - Petroni,N. L. A1 - Arbaugh, William A. KW - Communication system security KW - computer security KW - cryptography KW - design flaw mitigation KW - Dictionaries KW - legacy equipment KW - privacy KW - Protection KW - Protocols KW - security design flaws KW - security of data KW - synchronous active attack KW - telecommunication security KW - Telecommunication traffic KW - wired equivalent privacy protocol KW - Wireless LAN KW - wireless local area networks KW - Wireless networks AB - Mitigating design flaws often provides the only means to protect legacy equipment, particularly in wireless local area networks. A synchronous active attack against the wired equivalent privacy protocol demonstrates how mitigating one flaw or attack can facilitate another. VL - 1 SN - 1540-7993 CP - 1 M3 - 10.1109/MSECP.2003.1176993 ER - TY - RPRT T1 - Domain Tuning of Bilingual Lexicons for MT Y1 - 2003 A1 - Ayan,Necip F A1 - Dorr, Bonnie J A1 - Kolak,Okan KW - *DICTIONARIES KW - *FOREIGN LANGUAGES KW - accuracy KW - BILINGUAL LEXICONS KW - DOCUMENTS KW - linguistics KW - Vocabulary AB - Our overall objective is to translate a domain-specific document in a foreign language (in this case, Chinese) to English. Using automatically induced domain-specific, comparable documents and language-independent clustering, we apply domain-tuning techniques to a bilingual lexicon for downstream translation of the input document to English. We will describe our domain-tuning technique and demonstrate its effectiveness by comparing our results to manually constructed domain-specific vocabulary. Our coverage/accuracy experiments indicate that domain-tuned lexicons achieve 88/% precision and 66/% recall. We also ran a Bleu experiment to compare our domain-tuned version to its un-tuned counterpart in an IR Ni-style NIT system. Our domain-tuned lexicons brought about an improvement in the Blen scores: 9.4/% higher than a system trained on a uniformly- weighted dictionary and 275/% higher than a system trained on no dictionary at all. PB - Instititue for Advanced Computer Studies, Univ of Maryland, College Park UR - http://stinet.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA455197 ER - TY - CONF T1 - Energy-efficient broadcast and multicast trees for reliable wireless communication T2 - Wireless Communications and Networking, 2003. WCNC 2003. 2003 IEEE Y1 - 2003 A1 - Banerjee,S. A1 - Misra,A. A1 - Yeo,Jihwang A1 - Agrawala, Ashok K. KW - broadcast KW - channels;multicast KW - communication;broadcast KW - communication;network KW - data KW - delivery KW - energy-efficient KW - layer;multicast KW - network KW - networks;network KW - networks;telecommunication KW - paths;multicast KW - rates;link KW - reliability; KW - topologies;wireless KW - topology;radio KW - trees;error KW - trees;multihop KW - wireless AB - We define energy-efficient broadband and multicast schemes for reliable communication in multi-hop wireless networks. Unlike previous techniques, the choice of neighbors in the broadband and multicast trees in these schemes, are based not only on the link distance, but also on the error rates associated with the link. Our schemes can be implemented using both positive and negative acknowledgement based reliable broadcast techniques in the link layer. Through simulations, we show that our scheme achieves up to 45% improvement over previous schemes on realistic 100-node network topologies. A positive acknowledgment based implementation is preferred. Our simulations show that the additional benefits of a positive acknowledgement based implementation is marginal (1-2%). Therefore a negative acknowledgement based implementation of our schemes is equally applicable in constructing energy-efficient reliable and multicast data delivery paths. JA - Wireless Communications and Networking, 2003. WCNC 2003. 2003 IEEE VL - 1 M3 - 10.1109/WCNC.2003.1200429 ER - TY - JOUR T1 - Evaluation Techniques Applied to Domain Tuning of MT Lexicons JF - Proceedings of the Workshop “Towards Systematizing MT Evaluation Y1 - 2003 A1 - Ayan,N.F. A1 - Dorr, Bonnie J A1 - Kolak,O. AB - We describe a set of evaluation techniques applied to domain tuning of bilingual lexicons for machine translation.Our overall objective is to translate a domain-specific document in a foreign language (in this case, Chinese) to En- glish. First, we perform an intrinsic evaluation of the effectiveness of our domain-tuning techniques by comparing our domain-tuned lexicon to a manually constructed domain-specific bilingual termlist. Our results indicate that we achieve 66% recall and 95% precision with respect to a human-derived gold standard. Next, an extrinsic evaluation demonstrates that our domain-tuned lexicon improves the Bleu scores 50% over a statistical system—with a smaller improvement when the system is trained on a uniformly-weighted dictionary. VL - 27 ER - TY - CONF T1 - Exploiting Functional Decomposition for Efficient Parallel Processing of Multiple Data Analysis Queries T2 - Parallel and Distributed Processing Symposium, International Y1 - 2003 A1 - Andrade,Henrique A1 - Kurc,Tahsin A1 - Sussman, Alan A1 - Saltz,Joel AB - Reuse is a powerful method for increasing system performance. In this paper, we examine functional decomposition for improving data and computation reuse and, therefore, overall query execution performance in the context of data analysis applications. Additionally, we look at the performance effects of using various projection primitives that make it possible to transform intermediate results generated by a query so that they can be reused by a new query. A satellite data analysis application is used to experimentally show the performance benefits achieved using functional decomposition and projection primitives. JA - Parallel and Distributed Processing Symposium, International PB - IEEE Computer Society CY - Los Alamitos, CA, USA M3 - http://doi.ieeecomputersociety.org/10.1109/IPDPS.2003.1213184 ER - TY - CONF T1 - Eye design in the plenoptic space of light rays T2 - Ninth IEEE International Conference on Computer Vision, 2003. Proceedings Y1 - 2003 A1 - Neumann, J. A1 - Fermüller, Cornelia A1 - Aloimonos, J. KW - 3D ego-motion estimation KW - Assembly KW - B-splines KW - Camera design KW - CAMERAS KW - captured image KW - compound eyes KW - Computer vision KW - data mining KW - eye KW - eye-carrying organism KW - Eyes KW - filter optimization KW - image representation KW - image resolution KW - Information geometry KW - Laboratories KW - light field reconstruction KW - light gathering power KW - light rays KW - mixed spherical-Cartesian coordinate system KW - Motion estimation KW - natural evolution process KW - natural eye designs KW - natural image statistics KW - optical nanotechnology KW - Optical signal processing KW - optimal eye design mathematical criteria KW - Organisms KW - plenoptic image formation KW - plenoptic space KW - plenoptic video geometry KW - sampling operators KW - sensory ecology KW - Signal design KW - Signal processing KW - signal processing framework KW - signal processing tool KW - square-summable sequences KW - visual acuity AB - Natural eye designs are optimized with regard to the tasks the eye-carrying organism has to perform for survival. This optimization has been performed by the process of natural evolution over many millions of years. Every eye captures a subset of the space of light rays. The information contained in this subset and the accuracy to which the eye can extract the necessary information determines an upper limit on how well an organism can perform a given task. In this work we propose a new methodology for camera design. By interpreting eyes as sample patterns in light ray space we can phrase the problem of eye design in a signal processing framework. This allows us to develop mathematical criteria for optimal eye design, which in turn enables us to build the best eye for a given task without the trial and error phase of natural evolution. The principle is evaluated on the task of 3D ego-motion estimation. JA - Ninth IEEE International Conference on Computer Vision, 2003. Proceedings PB - IEEE SN - 0-7695-1950-4 M3 - 10.1109/ICCV.2003.1238623 ER - TY - CONF T1 - Interpolation over light fields with applications in computer graphics T2 - Proceedings of the Fifth Workshop on Algorithm Engineering and Experiments Y1 - 2003 A1 - Atalay,F. B A1 - Mount, Dave JA - Proceedings of the Fifth Workshop on Algorithm Engineering and Experiments ER - TY - CONF T1 - Kernel snakes: non-parametric active contour models T2 - IEEE International Conference on Systems, Man and Cybernetics, 2003 Y1 - 2003 A1 - Abd-Almageed, Wael A1 - Smith,C.E. A1 - Ramadan,S. KW - Active contours KW - Artificial intelligence KW - Bayes methods KW - Bayesian decision theory KW - Bayesian methods KW - decision theory KW - Deformable models KW - Image edge detection KW - Image segmentation KW - Intelligent robots KW - Kernel KW - kernel snakes KW - Laboratories KW - multicolored target tracking KW - nonparametric active contour models KW - nonparametric generalized formulation KW - nonparametric model KW - nonparametric statistics KW - nonparametric techniques KW - real time performance KW - Robot vision systems KW - statistical pressure snakes KW - target tracking AB - In this paper, a new non-parametric generalized formulation to statistical pressure snakes is presented. We discuss the shortcomings of the traditional pressure snakes. We then introduce a new generic pressure model that alleviates these shortcomings, based on the Bayesian decision theory. Non-parametric techniques are used to obtain the statistical models that drive the snake. We discuss the advantages of using the proposed non-parametric model compared to other parametric techniques. Multi-colored-target tracking is used to demonstrate the performance of the proposed approach. Experimental results show enhanced, real-time performance. JA - IEEE International Conference on Systems, Man and Cybernetics, 2003 PB - IEEE VL - 1 SN - 0-7803-7952-7 M3 - 10.1109/ICSMC.2003.1243822 ER - TY - JOUR T1 - Matrix Algorithms, Volume II: Eigensystems JF - Applied Mechanics Reviews Y1 - 2003 A1 - Stewart, G.W. A1 - Author A1 - Mahajan,A. A1 - Reviewer KW - algorithm theory KW - Eigenvalues and eigenfunctions KW - linear algebra KW - matrix algebra KW - reviews VL - 56 UR - http://link.aip.org/link/?AMR/56/B2/1 CP - 1 M3 - 10.1115/1.1523352 ER - TY - JOUR T1 - Measuring the effects of internet path faults on reactive routing JF - SIGMETRICS Perform. Eval. Rev. Y1 - 2003 A1 - Feamster, Nick A1 - Andersen,David G. A1 - Balakrishnan,Hari A1 - Kaashoek,M. Frans AB - Empirical evidence suggests that reactive routing systems improve resilience to Internet path failures. They detect and route around faulty paths based on measurements of path performance. This paper seeks to understand why and under what circumstances these techniques are effective.To do so, this paper correlates end-to-end active probing experiments, loss-triggered traceroutes of Internet paths, and BGP routing messages. These correlations shed light on three questions about Internet path failures: (1) Where do failures appear? (2) How long do they last? (3) How do they correlate with BGP routing instability?Data collected over 13 months from an Internet testbed of 31 topologically diverse hosts suggests that most path failures last less than fifteen minutes. Failures that appear in the network core correlate better with BGP instability than failures that appear close to end hosts. On average, most failures precede BGP messages by about four minutes, but there is often increased BGP traffic both before and after failures. Our findings suggest that reactive routing is most effective between hosts that have multiple connections to the Internet. The data set also suggests that passive observations of BGP routing messages could be used to predict about 20% of impending failures, allowing re-routing systems to react more quickly to failures. VL - 31 SN - 0163-5999 UR - http://doi.acm.org/10.1145/885651.781043 CP - 1 M3 - 10.1145/885651.781043 ER - TY - CONF T1 - New eyes for robotics T2 - 2003 IEEE/RSJ International Conference on Intelligent Robots and Systems, 2003. (IROS 2003). Proceedings Y1 - 2003 A1 - Baker, P. A1 - Ogale, A. S A1 - Fermüller, Cornelia A1 - Aloimonos, J. KW - 3D motion estimation KW - Argus eye KW - array signal processing KW - Birds KW - Calibration KW - CAMERAS KW - Control systems KW - Eyes KW - geometric configuration KW - imaging KW - imaging system KW - Layout KW - Motion estimation KW - multiple stereo configurations KW - Robot kinematics KW - robot vision KW - Robot vision systems KW - ROBOTICS KW - Robotics and automation KW - SHAPE KW - shape models AB - This paper describes an imaging system that has been designed to facilitate robotic tasks of motion. The system consists of a number of cameras in a network arranged so that they sample different parts of the visual sphere. This geometric configuration has provable advantages compared to small field of view cameras for the estimation of the system's own motion and consequently the estimation of shape models from the individual cameras. The reason is that inherent ambiguities of confusion between translation and rotation disappear. Pairs of cameras may also be arranged in multiple stereo configurations which provide additional advantages for segmentation. Algorithms for the calibration of the system and the 3D motion estimation are provided. JA - 2003 IEEE/RSJ International Conference on Intelligent Robots and Systems, 2003. (IROS 2003). Proceedings PB - IEEE VL - 1 SN - 0-7803-7860-1 M3 - 10.1109/IROS.2003.1250761 ER - TY - CONF T1 - Non-parametric expectation maximization: a learning automata approach T2 - IEEE International Conference on Systems, Man and Cybernetics, 2003 Y1 - 2003 A1 - Abd-Almageed, Wael A1 - El-Osery,A. A1 - Smith,C.E. KW - Automatic speech recognition KW - bivariate simulation data KW - Computational modeling KW - Computer vision KW - Density functional theory KW - expectation maximization technique KW - learning automata KW - mixture parameters estimation KW - nonparametric expectation maximization KW - nonparametric statistics KW - optimisation KW - parameter estimation KW - Parzen Window KW - PDF KW - probability KW - probability density function KW - Speech processing KW - Speech recognition KW - stochastic learning automata KW - Stochastic processes KW - stochastic technique AB - The famous expectation maximization technique suffers two major drawbacks. First, the number of components has to be specified apriori. Also, the expectation maximization is sensitive to initialization. In this paper, we present a new stochastic technique for estimating the mixture parameters. Parzen Window is used to estimate a discrete estimate of the PDF of the given data. Stochastic learning automata is then used to select the mixture parameters that minimize the distance between the discrete estimate of the PDF and the estimate of the expectation maximization. The validity of the proposed approach is verified using bivariate simulation data. JA - IEEE International Conference on Systems, Man and Cybernetics, 2003 PB - IEEE VL - 3 SN - 0-7803-7952-7 M3 - 10.1109/ICSMC.2003.1244347 ER - TY - CONF T1 - On-line computation of two types of structural relations in Japanese Y1 - 2003 A1 - Aoshima,S. A1 - Phillips,C. A1 - Weinberg, Amy ER - TY - JOUR T1 - Overlaying graph links on treemaps JF - IEEE Symposium on Information Visualization Conference Compendium (demonstration) Y1 - 2003 A1 - Fekete,J. D A1 - Wang,D. A1 - Dang,N. A1 - Aris,A. A1 - Plaisant, Catherine AB - Every graph can be decomposed into a tree structure plus a set ofremaining edges. We describe a visualization technique that displays the tree structure as a Treemap and the remaining edges as curved links overlaid on the Treemap. Link curves are designed to show where the link starts and where it ends without requiring an explicit arrow that would clutter the already dense visualization. This technique is effective for visualizing structures where the underlying tree has some meaning, such as Web sites or XML documents with cross-references. Graphic attributes of the links – such as color or thickness – can be used to represent attributes of the edges. Users can choose to see all links at once or only the links to and from the node or branch under the cursor. ER - TY - CONF T1 - Polydioptric camera design and 3D motion estimation T2 - 2003 IEEE Computer Society Conference on Computer Vision and Pattern Recognition, 2003. Proceedings Y1 - 2003 A1 - Neumann, J. A1 - Fermüller, Cornelia A1 - Aloimonos, J. KW - 3D motion estimation KW - Algorithm design and analysis KW - Application software KW - CAMERAS KW - Computer vision KW - Eyes KW - field-of-view camera KW - Image motion analysis KW - image sampling KW - image sensor KW - Image sensors KW - Layout KW - light ray KW - Motion estimation KW - multiperspective camera KW - optimal camera KW - optimal image formation KW - optimal sampling pattern KW - pinhole principle KW - polydioptric camera design KW - ray space KW - scene independent estimation KW - space structure analysis KW - stereo image processing KW - visual information processing AB - Most cameras used in computer vision applications are still based on the pinhole principle inspired by our own eyes. It has been found though that this is not necessarily the optimal image formation principle for processing visual information using a machine. We describe how to find the optimal camera for 3D motion estimation by analyzing the structure of the space formed by the light rays passing through a volume of space. Every camera corresponds to a sampling pattern in light ray space, thus the question of camera design can be rephrased as finding the optimal sampling pattern with regard to a given task. This framework suggests that large field-of-view multi-perspective (polydioptric) cameras are the optimal image sensors for 3D motion estimation. We conclude by proposing design principles for polydioptric cameras and describe an algorithm for such a camera that estimates its 3D motion in a scene independent and robust manner. JA - 2003 IEEE Computer Society Conference on Computer Vision and Pattern Recognition, 2003. Proceedings PB - IEEE VL - 2 SN - 0-7695-1900-8 M3 - 10.1109/CVPR.2003.1211483 ER - TY - JOUR T1 - Quantifying the causes of path inflation JF - Topology Y1 - 2003 A1 - Spring, Neil A1 - Mahajan,R. A1 - Anderson,T. VL - 100 ER - TY - JOUR T1 - Random doping-induced fluctuations of subthreshold characteristics in MOSFET devices JF - Solid-State Electronics Y1 - 2003 A1 - Andrei,Petru A1 - Mayergoyz, Issak D KW - Fluctuations KW - Mismatch KW - MOSFET KW - Sensitivity analysis KW - Statistics KW - Submicron devices AB - The random doping-induced fluctuations of subthreshold characteristics in MOSFET devices are analyzed. A technique for the computations of sensitivity coefficients and variances of subthreshold parameters is presented and applied to the computation of fluctuations of subthreshold current and gate-voltage swing. This technique is based on the linearization of transport equations with respect to the fluctuating quantities. It is computationally much more efficient than purely “statistical” methods (Monte-Carlo methods) that are based on the simulations of a large number of devices with different doping realizations. The numerical implementation of this technique is discussed and numerous computational results are presented. VL - 47 SN - 0038-1101 UR - http://www.sciencedirect.com/science/article/pii/S0038110103002363 CP - 11 M3 - 10.1016/S0038-1101(03)00236-3 ER - TY - JOUR T1 - Rapid porting of DUSTer to Hindi JF - ACM Transactions on Asian Language Information Processing (TALIP) Y1 - 2003 A1 - Dorr, Bonnie J A1 - Ayan,Necip Fazil A1 - Habash,Nizar A1 - Madnani,Nitin A1 - Hwa,Rebecca KW - Divergences KW - Machine translation AB - The frequent occurrence of divergences—structural differences between languages---presents a great challenge for statistical word-level alignment and machine translation. This paper describes the adaptation of DUSTer, a divergence unraveling package, to Hindi during the DARPA TIDES-2003 Surprise Language Exercise. We show that it is possible to port DUSTer to Hindi in under 3 days. VL - 2 SN - 1530-0226 UR - http://doi.acm.org/10.1145/974740.974744 CP - 2 M3 - 10.1145/974740.974744 ER - TY - BOOK T1 - Real 802.11 Security: Wi-Fi Protected Access and 802.11 i, 480 pages Y1 - 2003 A1 - Edney,J. A1 - Arbaugh, William A. PB - Addison Wesley ER - TY - JOUR T1 - Reduction of Cholera in Bangladeshi Villages by Simple Filtration JF - Proceedings of the National Academy of SciencesPNAS Y1 - 2003 A1 - Rita R Colwell A1 - Huq,Anwar A1 - M. Sirajul Islam A1 - K. M. A. Aziz A1 - Yunus,M. A1 - N. Huda Khan A1 - A. Mahmud A1 - Sack,R. Bradley A1 - Nair,G. B. A1 - J. Chakraborty A1 - Sack,David A. A1 - E. Russek-Cohen AB - Based on results of ecological studies demonstrating that Vibrio cholerae, the etiological agent of epidemic cholera, is commensal to zooplankton, notably copepods, a simple filtration procedure was developed whereby zooplankton, most phytoplankton, and particulates >20 μm were removed from water before use. Effective deployment of this filtration procedure, from September 1999 through July 2002 in 65 villages of rural Bangladesh, of which the total population for the entire study comprised ≈133,000 individuals, yielded a 48% reduction in cholera (P < 0.005) compared with the control. VL - 100 SN - 0027-8424, 1091-6490 UR - http://www.pnas.org/content/100/3/1051 CP - 3 M3 - 10.1073/pnas.0237386100 ER - TY - CONF T1 - Scriptroute: A public Internet measurement facility T2 - Proceedings of the 4th conference on USENIX Symposium on Internet Technologies and Systems-Volume 4 Y1 - 2003 A1 - Spring, Neil A1 - Wetherall,D. A1 - Anderson,T. JA - Proceedings of the 4th conference on USENIX Symposium on Internet Technologies and Systems-Volume 4 ER - TY - CONF T1 - A secure service discovery protocol for MANET T2 - 14th IEEE Proceedings on Personal, Indoor and Mobile Radio Communications, 2003. PIMRC 2003 Y1 - 2003 A1 - Yuan Yuan A1 - Arbaugh, William A. KW - ad hoc networks KW - centralized administration KW - Computer architecture KW - Computer science KW - dynamic service discovery infrastructure KW - Educational institutions KW - MANET KW - Manuals KW - mobile ad hoc network KW - Mobile ad hoc networks KW - Mobile computing KW - mobile radio KW - noninfrastructure network KW - Pervasive computing KW - Protocols KW - routing protocols KW - secure service discovery protocol KW - Security KW - service discovery techniques KW - service discovery technologies KW - telecommunication computing KW - telecommunication services KW - XML AB - Service discovery technologies are exploited to enable services to advertise their existence in a dynamic way, and can be discovered, configured and used by other devices with minimum manual efforts. It plays an essential role in future network scenarios especially with development of mobile ad hoc network (MANET) and emergence of pervasive computing. Because MANET allows these devices to communicate dynamically without fixed infrastructure and centralized administration, it gives rise to the challenges of the service discovery techniques. In this paper, we present a dynamic service discovery infrastructure that uses XML to describe services and match using the semantic content of service descriptions for MANET. We believe that the architecture we have designed is a necessary component of service discovery in non-infrastructure network by further exploring the secure and performance issues of this infrastructure. JA - 14th IEEE Proceedings on Personal, Indoor and Mobile Radio Communications, 2003. PIMRC 2003 PB - IEEE VL - 1 SN - 0-7803-7822-9 M3 - 10.1109/PIMRC.2003.1264322 ER - TY - JOUR T1 - SHOP2: An HTN planning system JF - J. Artif. Intell. Res. (JAIR) Y1 - 2003 A1 - Nau, Dana S. A1 - Au,T. C A1 - Ilghami,O. A1 - Kuter,U. A1 - Murdock,J. W. A1 - Wu,D. A1 - Yaman,F. AB - The SHOP2 planning system received one of the awards for distinguished performance in the 2002 International Planning Competition. This paper describes the features of SHOP2 which enabled it to excel in the competition, especially those aspects of SHOP2 that deal with temporal and metric planning domains. VL - 20 UR - https://www.aaai.org/Papers/JAIR/Vol20/JAIR-2013.pdf ER - TY - BOOK T1 - Special section on perceptual organization in computer vision Y1 - 2003 A1 - Jacobs, David W. A1 - Lindenbaum,M. A1 - August,J. A1 - Zucker,SW A1 - Ben-Shahar,O. A1 - Zucker,SW A1 - Tuytelaars,T. A1 - Turina,A. A1 - Van Gool,L. A1 - Mahamud,S. PB - IEEE Computer Society ER - TY - CONF T1 - Toward secure key distribution in truly ad-hoc networks T2 - Applications and the Internet Workshops, 2003. Proceedings. 2003 Symposium on Y1 - 2003 A1 - Khalili,A. A1 - Katz, Jonathan A1 - Arbaugh, William A. KW - ad KW - ad-hoc KW - cryptography; KW - distribution; KW - hoc KW - identity-based KW - key KW - mobile KW - network KW - networks; KW - routing; KW - secure KW - security; KW - Telecommunication KW - threshold KW - wireless AB - Ad-hoc networks - and in particular wireless mobile ad-hoc networks $have unique characteristics and constraints that make traditional cryptographic mechanisms and assumptions inappropriate. In particular it may not be warranted to assume pre-existing shared secrets between members of the network or the presence of a common PKI. Thus, the issue of key distribution in ad-hoc networks represents an important problem. Unfortunately, this issue has been largely ignored; as an example, most protocols for secure ad-hoc routing assume that key distribution has already taken place. Traditional key distribution schemes either do not apply in an ad-hoc scenario or are not efficient enough for small, resource-constrained devices. We propose to combine efficient techniques from identity-based (ID-based) and threshold cryptography to provide a mechanism that enables flexible and efficient key distribution while respecting the constraints of ad-hoc networks. We also discuss the available mechanisms and their suitability for the proposed task. JA - Applications and the Internet Workshops, 2003. Proceedings. 2003 Symposium on M3 - 10.1109/SAINTW.2003.1210183 ER - TY - CONF T1 - Towards domain-independent, task-oriented, conversational adequacy T2 - INTERNATIONAL JOINT CONFERENCE ON ARTIFICIAL IN℡LIGENCE Y1 - 2003 A1 - Josyula,D. P A1 - Anderson,M. L A1 - Perlis, Don JA - INTERNATIONAL JOINT CONFERENCE ON ARTIFICIAL IN℡LIGENCE VL - 18 ER - TY - JOUR T1 - Use of the SAND spatial browser for digital government applications JF - Commun. ACM Y1 - 2003 A1 - Samet, Hanan A1 - Alborzi,Houman A1 - Brabec,František A1 - Esperança,Claudio A1 - Hjaltason,Gísli R. A1 - Morgan,Frank A1 - Tanin,Egemen KW - GIS AB - Numerous federal agencies produce official statistics made accessible to ordinary citizens for searching and data retrieval. This is frequently done via the Internet through a Web browser interface. If this data is presented in textual format, it can often be searched and retrieved by such attributes as topic, responsible agency, keywords, or press release. However, if the data is of spatial nature, for example, in the form of a map, then using text-based queries is often too cumbersome for the intended audience. We describe the use of the SAND Spatial Browser to provide more power to users of these databases by enabling them to define and explore the specific spatial region of interest graphically. The SAND Spatial Browser allows users to form either purely spatial or mixed spatial/nonspatial queries intuitively, which can present information to users that might have been missed if only a textual interface was available. VL - 46 SN - 0001-0782 UR - http://doi.acm.org/10.1145/602421.602453 CP - 1 M3 - 10.1145/602421.602453 ER - TY - CONF T1 - User-level internet path diagnosis T2 - ACM SIGOPS Operating Systems Review Y1 - 2003 A1 - Mahajan,R. A1 - Spring, Neil A1 - Wetherall,D. A1 - Anderson,T. JA - ACM SIGOPS Operating Systems Review VL - 37 ER - TY - JOUR T1 - WLAN problems and solutions JF - Communications of the ACM Y1 - 2003 A1 - Housley,R. A1 - Arbaugh, William A. VL - 46 CP - 5 ER - TY - JOUR T1 - AAAI 2002 Workshops JF - AI Magazine Y1 - 2002 A1 - Blake,Brian A1 - Haigh,Karen A1 - Hexmoor,Henry A1 - Falcone,Rino A1 - Soh,Leen-Kiat A1 - Baral,Chitta A1 - McIlraith,Sheila A1 - Gmytrasiewicz,Piotr A1 - Parsons,Simon A1 - Malaka,Rainer A1 - Krueger,Antonio A1 - Bouquet,Paolo A1 - Smart,Bill A1 - Kurumantani,Koichi A1 - Pease,Adam A1 - Brenner,Michael A1 - desJardins, Marie A1 - Junker,Ulrich A1 - Delgrande,Jim A1 - Doyle,Jon A1 - Rossi,Francesca A1 - Schaub,Torsten A1 - Gomes,Carla A1 - Walsh,Toby A1 - Guo,Haipeng A1 - Horvitz,Eric J A1 - Ide,Nancy A1 - Welty,Chris A1 - Anger,Frank D A1 - Guegen,Hans W A1 - Ligozat,Gerald VL - 23 SN - 0738-4602 UR - http://www.aaai.org/ojs/index.php/aimagazine/article/viewArticle/1678 CP - 4 M3 - 10.1609/aimag.v23i4.1678 ER - TY - CONF T1 - Active Proxy-G: Optimizing the query execution process in the Grid T2 - Proceedings of the 2002 ACM/IEEE conference on Supercomputing Y1 - 2002 A1 - Andrade,H. A1 - Kurc, T. A1 - Sussman, Alan A1 - Saltz, J. JA - Proceedings of the 2002 ACM/IEEE conference on Supercomputing ER - TY - JOUR T1 - AD (Attacker Defender) Game JF - Technical Reports from UMIACS, UMIACS-TR-2001-45 Y1 - 2002 A1 - Kochut,Andrzej A1 - Agrawala, Ashok K. A1 - Larsen,Ronald L A1 - A. Udaya Shankar KW - Technical Report AB - Information Dynamics is a framework for agent-based systems that givesa central position to the role of information, time, and the value of information. We illustrate system design in the Information Dynamics Framework by developing an intelligence game called AD involving attackers, defenders and targets operating in some space of locations. The goal of the attackers is to destroy all targets. Target destruction takes place when the number of attackers in the target's neighborhood exceeds the number of defenders in this neighborhood by a value WINNING_DIFFERENCE. The goal of defenders is to prevent attackers from achieving their goal. (Also UMIACS-TR-2001-45) UR - http://drum.lib.umd.edu/handle/1903/1142 ER - TY - JOUR T1 - Algorithmic issues in modeling motion JF - ACM Comput. Surv. Y1 - 2002 A1 - Agarwal,Pankaj K. A1 - Guibas,Leonidas J. A1 - Edelsbrunner,Herbert A1 - Erickson,Jeff A1 - Isard,Michael A1 - Har-Peled,Sariel A1 - Hershberger,John A1 - Jensen,Christian A1 - Kavraki,Lydia A1 - Koehl,Patrice A1 - Lin,Ming A1 - Manocha,Dinesh A1 - Metaxas,Dimitris A1 - Mirtich,Brian A1 - Mount, Dave A1 - Muthukrishnan,S. A1 - Pai,Dinesh A1 - Sacks,Elisha A1 - Snoeyink,Jack A1 - Suri,Subhash A1 - Wolefson,Ouri KW - computational geometry KW - Computer vision KW - mobile networks KW - modeling KW - molecular biology KW - motion modeling KW - physical simulation KW - robotoics KW - spatio-temporal databases AB - This article is a survey of research areas in which motion plays a pivotal role. The aim of the article is to review current approaches to modeling motion together with related data structures and algorithms, and to summarize the challenges that lie ahead in producing a more unified theory of motion representation that would be useful across several disciplines. VL - 34 SN - 0360-0300 UR - http://doi.acm.org/10.1145/592642.592647 CP - 4 M3 - 10.1145/592642.592647 ER - TY - CONF T1 - ALLI: An Information Integration System Based on Active Logic Framework T2 - Proceedings of the Third International Conference on Management Information Systems, Greece Y1 - 2002 A1 - Barfourosh,A. A. A1 - Nezhad,H. R.M A1 - Anderson,M. A1 - Perlis, Don JA - Proceedings of the Third International Conference on Management Information Systems, Greece ER - TY - JOUR T1 - Approximating the head-related transfer function using simple geometric models of the head and torso JF - The Journal of the Acoustical Society of America Y1 - 2002 A1 - Algazi,V. R A1 - Duda,R. O A1 - Duraiswami, Ramani A1 - Gumerov, Nail A. A1 - Tang,Z. VL - 112 ER - TY - CONF T1 - Argument structure saturation in a constraint based model Y1 - 2002 A1 - Drury,J. A1 - Resnik, Philip A1 - Weinberg, Amy A1 - Gennari,S. A1 - Aoshima,S. UR - http://cognet.mit.edu/library/conferences/paper?paper_id=55048 ER - TY - CHAP T1 - An Augmented Visual Query Mechanism for Finding Patterns in Time Series Data T2 - Flexible Query Answering SystemsFlexible Query Answering Systems Y1 - 2002 A1 - Keogh,Eamonn A1 - Hochheiser,Harry A1 - Shneiderman, Ben ED - Carbonell,Jaime ED - Siekmann,Jörg ED - Andreasen,Troels ED - Christiansen,Henning ED - Motro,Amihai ED - Legind Larsen,Henrik AB - Relatively few query tools exist for data exploration and pattern identification in time series data sets. In previous work we introduced Timeboxes . Timeboxes are rectangular, direct-manipulation queries for studying time-series datasets. We demonstrated how Timeboxes can be used to support interactive exploration via dynamic queries, along with overviews of query results and drag-and-drop support for query-by-example. In this paper, we extend our work by introducing Variable Time Timeboxes (VTT). VTTs are a natural generalization of Timeboxes, which permit the specification of queries that allow a degree of uncertainty in the time axis. We carefully motivate the need for these more expressive queries, and demonstrate the utility of our approach on several data sets. JA - Flexible Query Answering SystemsFlexible Query Answering Systems T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 2522 SN - 978-3-540-00074-7 UR - http://dx.doi.org/10.1007/3-540-36109-X_19 ER - TY - JOUR T1 - Bias in visual motion processes: A theory predicting illusions JF - Statistical Methods in Video Processing.(in conjunction with European Conference on Computer Vision) Y1 - 2002 A1 - Fermüller, Cornelia A1 - Aloimonos, J. A1 - Malm,H. AB - The first step in the interpretation of video sequences is theestimation of spatio-temporal image representations, that is the image motion or the correspondence of points or lines. Noise in the data, however, causes a serious problem for their estimation; in particular, it causes bias. As a result the location of image points, the orientation of image lines and the length and orientation of image motion vectors are esti- mated erroneously. It is suggested that machine vision sys- tems processing video should include statistical procedures to alleviate the bias. However, complete correction in gen- eral does not appear to be feasible, and this provides an ex- planation for most well-known geometrical optical illusions, such as the café wall, the Zöllner, the Poggendorff illusion and other recently discovered illusions of movement. ER - TY - CONF T1 - On cache replacement policies for servicing mixed data intensive query workloads T2 - Proceedings of the 2nd Workshop on Caching, Coherence, and Consistency, held in conjunction with the 16th ACM International Conference on Supercomputing Y1 - 2002 A1 - Andrade,H. A1 - Kurc, T. A1 - Sussman, Alan A1 - Borovikov,E. A1 - Saltz, J. AB - When data analysis applications are employed in a multi-client environment, a data server must service multiple si- multaneous queries, each of which may employ complex user-defined data structures and operations on the data. It is then necessary to harness inter- and intra-query com- monalities and system resources to improve the performance of the data server. We have developed a framework and customizable middleware to enable reuse of intermediate and final results among queries, through an in-memory ac- tive semantic cache and user-defined transformation func- tions. Since resources such as processing power and mem- ory space are limited on the machine hosting the server, ef- fective scheduling of incoming queries and efficient cache replacement policies are challenging issues that must be ad- dressed. We have worked on the scheduling problem in ear- lier work, and in this paper we describe and evaluate several cache replacement policies. We present experimental eval- uation of the policies on a shared-memory parallel system using two applications from different application domains. JA - Proceedings of the 2nd Workshop on Caching, Coherence, and Consistency, held in conjunction with the 16th ACM International Conference on Supercomputing ER - TY - CONF T1 - CaMeL: Learning method preconditions for HTN planning Y1 - 2002 A1 - Ilghami,O. A1 - Nau, Dana S. A1 - Munoz-Avila,H. A1 - Aha,D. W. AB - A great challenge in using any planning system to solve real-world problems is the difficulty of acquiring the do- main knowledge that the system will need. We present a way to address part of this problem, in the context of Hierarchical Task Network (HTN) planning, by having the planning system incrementally learn conditions for HTN methods under expert supervision. We present a general formal framework for learning HTN methods, and a supervised learning algorithm, named CaMeL, based on this formalism. We present theoretical results about CaMeL’s soundness, completeness, and conver- gence properties. We also report experimental results about its speed of convergence under different condi- tions. The experimental results suggest that CaMeL has the potential to be useful in real-world applications. UR - https://www.aaai.org/Papers/AIPS/2002/AIPS02-014.pdf ER - TY - CONF T1 - Clustering and server selection using passive monitoring T2 - IEEE INFOCOM 2002. Twenty-First Annual Joint Conference of the IEEE Computer and Communications Societies. Proceedings Y1 - 2002 A1 - Andrews,M. A1 - Shepherd,B. A1 - Srinivasan, Aravind A1 - Winkler,P. A1 - Zane,F. KW - client assignment KW - client-server systems KW - clustering KW - content servers KW - Delay KW - distributed system KW - Educational institutions KW - Internet KW - IP addresses KW - Monitoring KW - network conditions KW - Network servers KW - Network topology KW - optimal content server KW - passive monitoring KW - server selection KW - Space technology KW - TCPIP KW - Transport protocols KW - Web pages KW - Web server KW - Webmapper AB - We consider the problem of client assignment in a distributed system of content servers. We present a system called Webmapper for clustering IP addresses and assigning each cluster to an optimal content server. The system is passive in that the only information it uses comes from monitoring the TCP connections between the clients and the servers. It is also flexible in that it makes no a priori assumptions about network topology and server placement and it can react quickly to changing network conditions. We present experimental results to evaluate the performance of Webmapper. JA - IEEE INFOCOM 2002. Twenty-First Annual Joint Conference of the IEEE Computer and Communications Societies. Proceedings PB - IEEE VL - 3 SN - 0-7803-7476-2 M3 - 10.1109/INFCOM.2002.1019425 ER - TY - CHAP T1 - On the Complexity of Plan Adaptation by Derivational Analogy in a Universal Classical Planning Framework T2 - Advances in Case-Based Reasoning Y1 - 2002 A1 - Au,Tsz-Chiu A1 - Muñoz-Avila,Héctor A1 - Nau, Dana S. ED - Craw,Susan ED - Preece,Alun KW - Computer science AB - In this paper we present an algorithm called DerUCP, which can be regarded as a general model for plan adaptation using Derivational Analogy. Using DerUCP, we show that previous results on the complexity of plan adaptation do not apply to Derivational Analogy. We also show that Derivational Analogy can potentially produce exponential reductions in the size of the search space generated by a planning system. JA - Advances in Case-Based Reasoning T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 2416 SN - 978-3-540-44109-0 UR - http://www.springerlink.com/content/db2mr13j90mfrcaw/abstract/ ER - TY - CONF T1 - Contour migration: solving object ambiguity with shape-space visual guidance T2 - IEEE/RSJ International Conference on Intelligent Robots and Systems, 2002 Y1 - 2002 A1 - Abd-Almageed, Wael A1 - Smith,C.E. KW - Artificial intelligence KW - camera motion KW - CAMERAS KW - Computer vision KW - contour migration KW - Databases KW - edge detection KW - Intelligent robots KW - Laboratories KW - Machine vision KW - object ambiguity KW - Object recognition KW - pattern matching KW - Robot vision systems KW - servomechanisms KW - SHAPE KW - shape matching KW - shape-space visual guidance KW - silhouette matching KW - visual servoing AB - A fundamental problem in computer vision is the issue of shape ambiguity. Simply stated, a silhouette cannot uniquely identify an object or an object's classification since many unique objects can present identical occluding contours. This problem has no solution in the general case for a monocular vision system. This paper presents a method for disambiguating objects during silhouette matching using a visual servoing system. This method identifies the camera motion(s) that gives disambiguating views of the objects. These motions are identified through a new technique called contour migration. The occluding contour's shape is used to identify objects or object classes that are potential matches for that shape. A contour migration is then determined that disambiguates the possible matches by purposive viewpoint adjustment. The technique is demonstrated using an example set of objects. JA - IEEE/RSJ International Conference on Intelligent Robots and Systems, 2002 PB - IEEE VL - 1 SN - 0-7803-7398-7 M3 - 10.1109/IRDS.2002.1041410 ER - TY - JOUR T1 - Efficient Data Processing using Cross Layer Hints JF - Technical Reports from UMIACS, UMIACS-TR-2002-59 Y1 - 2002 A1 - Banerjee,Suman A1 - Agrawala, Ashok K. A1 - Kramer,Michael J KW - Technical Report AB - Conventional network stacks define a layered architecture, whereeach layer implements a set of services and exports a well-defined interface to be used by its immediate upper layer. A key design choice of the layered architecture has been to provide isolation between the functional modules of distinct layers. While such an architecture provides an useful abstraction for system development, the strict isolation of this layered architecture limits the flexibility of tailoring the behavior of the lower layers of the stack to the needs of the application. In this paper we define a new architecture, called X-Tags, which allows flexible interaction between layers for cooperative data processing without impacting the isolation property. In this architecture, applications use special tags to provide semantic hints for data processing to lower layers. We motivate the usefulness of this architecture by describing ts applicability to some emerging applications. UMIACS-TR-2002-59 UR - http://drum.lib.umd.edu/handle/1903/1211 ER - TY - CONF T1 - An experimental evaluation of linear and kernel-based methods for face recognition T2 - Applications of Computer Vision, 2002. (WACV 2002). Proceedings. Sixth IEEE Workshop on Y1 - 2002 A1 - Gupta, H. A1 - Agrawala, Ashok K. A1 - Pruthi, T. A1 - Shekhar, C. A1 - Chellapa, Rama KW - analysis; KW - classification; KW - component KW - discriminant KW - Face KW - image KW - Kernel KW - linear KW - Machine; KW - nearest KW - neighbor; KW - principal KW - recognition; KW - Support KW - vector AB - In this paper we present the results of a comparative study of linear and kernel-based methods for face recognition. The methods used for dimensionality reduction are Principal Component Analysis (PCA), Kernel Principal Component Analysis (KPCA), Linear Discriminant Analysis (LDA) and Kernel Discriminant Analysis (KDA). The methods used for classification are Nearest Neighbor (NN) and Support Vector Machine (SVM). In addition, these classification methods are applied on raw images to gauge the performance of these dimensionality reduction techniques. All experiments have been performed on images from UMIST Face Database. JA - Applications of Computer Vision, 2002. (WACV 2002). Proceedings. Sixth IEEE Workshop on M3 - 10.1109/ACV.2002.1182137 ER - TY - CONF T1 - Eye tracking using active deformable models T2 - Proc. of the IIIrd Indian Conference on Computer Vision, Graphics and Image Processing Y1 - 2002 A1 - Ramadan,S. A1 - Abd-Almageed, Wael A1 - Smith,C.E. JA - Proc. of the IIIrd Indian Conference on Computer Vision, Graphics and Image Processing ER - TY - CONF T1 - Eyes form eyes: New cameras for structure from motion T2 - Proceedings Workshop on Omnidirectional Vision (OMNIVIS) Y1 - 2002 A1 - Neumann, J. A1 - Fermüller, Cornelia A1 - Aloimonos, J. JA - Proceedings Workshop on Omnidirectional Vision (OMNIVIS) ER - TY - CONF T1 - Eyes from eyes: new cameras for structure from motion T2 - Third Workshop on Omnidirectional Vision, 2002. Proceedings Y1 - 2002 A1 - Neumann, J. A1 - Fermüller, Cornelia A1 - Aloimonos, J. KW - Algorithm design and analysis KW - Camera design KW - CAMERAS KW - Design automation KW - differential stereo KW - Educational institutions KW - ego-motion estimation KW - Eyes KW - Geometrical optics KW - IMAGE PROCESSING KW - Layout KW - Motion estimation KW - observed scene KW - Optical films KW - polydioptric camera KW - RETINA AB - We investigate the relationship between camera design and the problem of recovering the motion and structure of a scene from video data. The visual information that could possibly be obtained is described by the plenoptic function. A camera can be viewed as a device that captures a subset of this function, that is, it measures some of the light rays in some part of the space. The information contained in the subset determines how difficult it is to solve subsequent interpretation processes. By examining the differential structure of the time varying plenoptic function we relate different known and new camera models to the spatiotemporal structure of the observed scene. This allows us to define a hierarchy of camera designs, where the order is determined by the stability and complexity of the computations necessary to estimate structure and motion. At the low end of this hierarchy is the standard planar pinhole camera for which the structure from motion problem is non-linear and ill-posed. At the high end is a new camera, which we call the full field of view polydioptric camera, for which the problem is linear and stable. In between are multiple-view cameras with large fields of view which we have built, as well as catadioptric panoramic sensors and other omni-directional cameras. We develop design suggestions for the polydioptric camera, and based upon this new design we propose a linear algorithm for ego-motion estimation, which in essence combines differential motion estimation with differential stereo. JA - Third Workshop on Omnidirectional Vision, 2002. Proceedings PB - IEEE SN - 0-7695-1629-7 M3 - 10.1109/OMNVIS.2002.1044486 ER - TY - JOUR T1 - Flow-sensitive type qualifiers JF - ACM SIGPLAN Notices Y1 - 2002 A1 - Foster, Jeffrey S. A1 - Terauchi,T. A1 - Aiken,A. VL - 37 CP - 5 ER - TY - JOUR T1 - Generating A Parsing Lexicon from an LCS-Based Lexicon JF - LREC 2002 Workshop Proceedings: Linguistic Knowledge Acquisition and Representation: Bootstrapping Annotated Language Data Y1 - 2002 A1 - Ayan,N.F. A1 - Dorr, Bonnie J AB - This paper describes a technique for generating parsing lexicons for a principle-based parser (Minipar). Our approach mapslexical entries in a large LCS-based repository of semantically classified verbs to their corresponding syntactic patterns. A by-product of this mapping is a lexicon that is directly usable in the Minipar system. We evaluate the accuracy and coverage of this lexicon using LDOCE syntactic codes as a gold standard. We show that this lexicon is comparable to the hand-generated Minipar lexicon (i.e., similar recall and precision values). In a later experiment, we automate the process of mapping between the LCS-based repository and syntactic patterns. The advantage of automating the process is that the same technique can be applied directly to lexicons we have for other languages, for example, Arabic, Chinese, and Spanish. ER - TY - RPRT T1 - Generating A Parsing Lexicon From Lexical-Conceptual Structure Y1 - 2002 A1 - Ayan,N.F. A1 - Dorr, Bonnie J AB - This paper describes the generation of a lexicon for a principle-based parser (Minipar[5,6]) using descriptions of verbs based on Lexical-Conceptual Structure (LCS [1,2]).1 We aim to determine how much syntactic information we can obtain from a semantic- based lexicon. More specifically, we aim to provide a general approach to projection of syntactic entries from semantic (language-independent) lexicons-and to test the effect of such lexicons on parser performance. Verbs are grouped together into classes-each denoted by an LCS representation adn the thematic grid. These are mapped systemat- ically into syntactic categories associated with entries in the Minipar parser. The main advantage of this LCS-to-syntax projection is language protability: We currently have LCS lexicons for English, Arabic, Spanish, and Chinese; thus, our LCS-projection ap- proach allows us to produce syntactic lexicons for parsing in each of these languages. For comparing the performance of the projection from the LCS to Minpar coes, we also generated the mappings for the codes of Longman's Directionary of Contemporary En- glish (LDOCE [8])-the most comprehensive online dictionary for syntactic categorization. Preliminary experiments indicate that our approach yields a categorization of verbs with 58% precision and 65% recall as measured against LDOCE-with an improved precision of 74% when redundancy is removed. The next section presents a brief description of each code set we use. In Section 3, we explain how we generated Minipar codes from LCS representation. Finally, Section 4, discusses our experiments and results. PB - Instititue for Advanced Computer Studies, Univ of Maryland, College Park ER - TY - JOUR T1 - Genome sequence and comparative analysis of the model rodent malaria parasite Plasmodium yoelii yoelii JF - Nature Y1 - 2002 A1 - Carlton,Jane M. A1 - Angiuoli,Samuel V A1 - Suh,Bernard B. A1 - Kooij,Taco W. A1 - Pertea,Mihaela A1 - Silva,Joana C. A1 - Ermolaeva,Maria D. A1 - Allen,Jonathan E A1 - Jeremy D Selengut A1 - Koo,Hean L. A1 - Peterson,Jeremy D. A1 - Pop, Mihai A1 - Kosack,Daniel S. A1 - Shumway,Martin F. A1 - Bidwell,Shelby L. A1 - Shallom,Shamira J. A1 - Aken,Susan E. van A1 - Riedmuller,Steven B. A1 - Feldblyum,Tamara V. A1 - Cho,Jennifer K. A1 - Quackenbush,John A1 - Sedegah,Martha A1 - Shoaibi,Azadeh A1 - Cummings,Leda M. A1 - Florens,Laurence A1 - Yates,John R. A1 - Raine,J. Dale A1 - Sinden,Robert E. A1 - Harris,Michael A. A1 - Cunningham,Deirdre A. A1 - Preiser,Peter R. A1 - Bergman,Lawrence W. A1 - Vaidya,Akhil B. A1 - Lin,Leo H. van A1 - Janse,Chris J. A1 - Waters,Andrew P. A1 - Smith,Hamilton O. A1 - White,Owen R. A1 - Salzberg,Steven L. A1 - Venter,J. Craig A1 - Fraser,Claire M. A1 - Hoffman,Stephen L. A1 - Gardner,Malcolm J. A1 - Carucci,Daniel J. AB - Species of malaria parasite that infect rodents have long been used as models for malaria disease research. Here we report the whole-genome shotgun sequence of one species, Plasmodium yoelii yoelii, and comparative studies with the genome of the human malaria parasite Plasmodium falciparum clone 3D7. A synteny map of 2,212 P. y. yoelii contiguous DNA sequences (contigs) aligned to 14 P. falciparum chromosomes reveals marked conservation of gene synteny within the body of each chromosome. Of about 5,300 P. falciparum genes, more than 3,300 P. y. yoelii orthologues of predominantly metabolic function were identified. Over 800 copies of a variant antigen gene located in subtelomeric regions were found. This is the first genome sequence of a model eukaryotic parasite, and it provides insight into the use of such systems in the modelling of Plasmodium biology and disease. VL - 419 SN - 0028-0836 UR - http://www.nature.com/nature/journal/v419/n6906/full/nature01099.html CP - 6906 M3 - 10.1038/nature01099 ER - TY - CONF T1 - Hidden Markov models for silhouette classification T2 - Automation Congress, 2002 Proceedings of the 5th Biannual World Y1 - 2002 A1 - Abd-Almageed, Wael A1 - Smith,C. KW - Computer vision KW - Feature extraction KW - Fourier transforms KW - hidden Markov models KW - HMM KW - image classification KW - Neural networks KW - object classification KW - Object recognition KW - parameter estimation KW - pattern recognition KW - Probability distribution KW - Shape measurement KW - silhouette classification KW - Wavelet transforms AB - In this paper, a new technique for object classification from silhouettes is presented. Hidden Markov models are used as a classification mechanism. Through a set of experiments, we show the validity of our approach and show its invariance under severe rotation conditions. Also, a comparison with other techniques that use hidden Markov models for object classification from silhouettes is presented. JA - Automation Congress, 2002 Proceedings of the 5th Biannual World PB - IEEE VL - 13 SN - 1-889335-18-5 M3 - 10.1109/WAC.2002.1049575 ER - TY - JOUR T1 - Identification of non-autonomous non-LTR retrotransposons in the genome of Trypanosoma cruzi JF - Molecular and Biochemical Parasitology Y1 - 2002 A1 - Bringaud,Frédéric A1 - García-Pérez,José Luis A1 - Heras,Sara R. A1 - Ghedin,Elodie A1 - El‐Sayed, Najib M. A1 - Andersson,Björn A1 - Baltz,Théo A1 - Lopez,Manuel C. KW - Ingi KW - L1Tc KW - Non-LTR retrotransposon KW - RIME KW - Trypanosoma brucei KW - Trypanosoma cruzi AB - As observed for most eukaryotic cells, trypanosomatids contains non-LTR retrotransposons randomly inserted in the nuclear genome. Autonomous retroelements which, code for their own transposition, have been characterized in Trypanosoma brucei (ingi) and Trypanosoma cruzi (L1Tc), whereas non-autonomous retroelements have only been characterized in T. brucei (RIME). Here, we have characterized in the genome of Trypanosoma cruzi four complete copies of a non-autonomous non-LTR retrotransposon, called NARTc. This 0.26 kb NARTc element has the characteristics of non-LTR retrotransposons: the presence a poly(dA) tail and of a short flanking duplicated motif. Analysis of the Genome Survey Sequence databases indicated that the Trypanosoma cruzi haploid genome contains about 140 NARTc copies and about twice as many L1Tc copies. Interestingly, the NARTc and L1Tc retroelements share, with the Trypanosoma brucei ingi and RIME retrotransposons, a common sequence (the first 45 bp with 91% identity), whereas the remaining sequences are very divergent. This suggests that these four trypanosome non-LTR retrotransposons were derived from the same common ancester and the sequence of their 5'-extremity may have a functional role. In addition, the genome of Leishmania major contains the same conserved motif present in the trypanosome retroelements, whicle no transposable elements have been detected so far in Leishmania sp. VL - 124 SN - 0166-6851 UR - http://www.sciencedirect.com/science/article/pii/S0166685102001676 CP - 1-2 M3 - 16/S0166-6851(02)00167-6 ER - TY - CONF T1 - Inferring link weights using end-to-end measurements T2 - Proceedings of the 2nd ACM SIGCOMM Workshop on Internet measurment Y1 - 2002 A1 - Mahajan,Ratul A1 - Spring, Neil A1 - Wetherall,David A1 - Anderson,Tom AB - We describe a novel constraint-based approach to approximate ISP link weights using only end-to-end measurements. Common routing protocols such as OSPF and IS-IS choose least-cost paths using link weights, so inferred weights provide a simple, concise, and useful model of intradomain routing. Our approach extends router-level ISP maps, which include only connectivity, with link weights that are consistent with routing. Our inferred weights agree well with observed routing: while our inferred weights fully characterize the set of shortest paths between 84--99% of the router-pairs, alternative models based on hop count and latency do so for only 47--81% of the pairs. JA - Proceedings of the 2nd ACM SIGCOMM Workshop on Internet measurment T3 - IMW '02 PB - ACM CY - New York, NY, USA SN - 1-58113-603-X UR - http://doi.acm.org/10.1145/637201.637237 M3 - 10.1145/637201.637237 ER - TY - RPRT T1 - Metareasoning for More Effective Human-Computer Dialogue Y1 - 2002 A1 - Perlis, Don A1 - Anderson,Mike KW - *LEARNING MACHINES KW - COMPUTER LOGIC KW - COMPUTER PROGRAMMING AND SOFTWARE KW - CYBERNETICS KW - MAN COMPUTER INTERFACE KW - METAREASONING KW - NATURAL LANGUAGE. KW - PROCESSING AB - The research project explores specific meta-dialogue behaviors in terms of both how a system could be made to perform them, and to what extent they can increase overall system performance. We focus on two types of meta-dialogue capabilities: ability to detect and recover from anomalous dialogue patterns in simple exchanges, and on-line extensions or changes to working vocabulary. Our main method involves detailed representation of the dialogue context, separating domain, language, and dialogue specific aspects, and significant amounts of meta-reasoning about the system's processing of these representations. An existing logical inference system, ALMA/CARNE, developed as part of a pilot study, is being used in an implementation phase of this work. We are also engaged in a study of existing dialogue corpora to investigate the range and frequency of meta-dialogue expressions in different task domains. PB - University of Maryland, College Park UR - http://stinet.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA414209 ER - TY - CONF T1 - Mixture models for dynamic statistical pressure snakes T2 - 16th International Conference on Pattern Recognition, 2002. Proceedings Y1 - 2002 A1 - Abd-Almageed, Wael A1 - Smith,C.E. KW - active contour models KW - Active contours KW - Artificial intelligence KW - Bayes methods KW - Bayesian methods KW - Bayesian theory KW - complex colored object KW - Computer vision KW - decision making KW - decision making mechanism KW - dynamic statistical pressure snakes KW - Equations KW - expectation maximization algorithm KW - Gaussian distribution KW - image colour analysis KW - Image edge detection KW - Image segmentation KW - Intelligent robots KW - mixture models KW - mixture of Gaussians KW - mixture pressure model KW - Robot vision systems KW - robust pressure model KW - Robustness KW - segmentation results KW - statistical analysis KW - statistical modeling AB - This paper introduces a new approach to statistical pressure snakes. It uses statistical modeling for both object and background to obtain a more robust pressure model. The Expectation Maximization (EM) algorithm is used to model the data into a Mixture of Gaussians (MoG). Bayesian theory is then employed as a decision making mechanism. Experimental results using the traditional pressure model and the new mixture pressure model demonstrate the effectiveness of the new models. JA - 16th International Conference on Pattern Recognition, 2002. Proceedings PB - IEEE VL - 2 SN - 0-7695-1695-X M3 - 10.1109/ICPR.2002.1048404 ER - TY - CONF T1 - Multiple Query Optimization for Data Analysis Applications on Clusters of SMPs T2 - 2nd IEEE/ACM International Symposium on Cluster Computing and the Grid, 2002 Y1 - 2002 A1 - Andrade,H. A1 - Kurc, T. A1 - Sussman, Alan A1 - Saltz, J. KW - Aggregates KW - Application software KW - Bandwidth KW - Data analysis KW - Data structures KW - Delay KW - Query processing KW - scheduling KW - Subcontracting KW - Switched-mode power supply AB - This paper is concerned with the efficient execution of multiple query workloads on a cluster of SMPs. We target applications that access and manipulate large scientific datasets. Queries in these applications involve user-defined processing operations and distributed data structures to hold intermediate and final results. Our goal is to implement system components to leverage previously computed query results and to effectively utilize processing power and aggregated I/O bandwidth on SMP nodes so that both single queries and multi-query batches can be efficiently executed. JA - 2nd IEEE/ACM International Symposium on Cluster Computing and the Grid, 2002 PB - IEEE SN - 0-7695-1582-7 M3 - 10.1109/CCGRID.2002.1017123 ER - TY - CONF T1 - A non-intrusive Kalman filter-based tracker for pursuit eye movement T2 - American Control Conference, 2002. Proceedings of the 2002 Y1 - 2002 A1 - Abd-Almageed, Wael A1 - Fadali,M. S A1 - Bebis,G. KW - Application software KW - characterization KW - Computer vision KW - Current measurement KW - deterministic component KW - Electric variables measurement KW - eye position estimation KW - eye tracking KW - gaze tracking KW - Human computer interaction KW - Kalman filter KW - Kalman filters KW - Lenses KW - Motion estimation KW - Optical reflection KW - pursuit eye movement KW - pursuit motion KW - random component KW - Skin KW - tracking AB - In this paper, we introduce a new non-intrusive approach to estimating the eye position during pursuit motion of the eye. We introduce a new characterization for the pursuit eye movement. Our characterization is based on the decomposition of the pursuit eye motion into a deterministic component and random component. We use a discrete Kalman filter to estimate the random component and calculate the deterministic component. We add the two components to obtain an estimate of the eye position. Simulation results are provided to illustrate the eye position estimation. JA - American Control Conference, 2002. Proceedings of the 2002 PB - IEEE VL - 2 SN - 0-7803-7298-0 UR - http://ieeexplore.ieee.org/ielx5/7965/22015/01023224.pdf?tp=&arnumber=1023224&isnumber=22015 M3 - 10.1109/ACC.2002.1023224 ER - TY - CONF T1 - Persistent caching in a multiple query optimization framework T2 - Proceedings of the 6th Workshop on Languages, Compilers, and Run-Time Systems for Scalable Computers Y1 - 2002 A1 - Andrade,H. A1 - Kurc, T. A1 - Catalyurek,U. A1 - Sussman, Alan A1 - Saltz, J. AB - This paper focuses on persistent caching in multi-client en-vironments, which aims to improve the performance of a data server by caching on disk query results that can be expensive to produce. We present and evaluate extensions to an existing multi-query optimization framework, called MQO, to incorporate persistent caching capabilities. JA - Proceedings of the 6th Workshop on Languages, Compilers, and Run-Time Systems for Scalable Computers ER - TY - JOUR T1 - Polydioptric cameras: New eyes for structure from motion JF - Pattern Recognition Y1 - 2002 A1 - Neumann, J. A1 - Fermüller, Cornelia A1 - Aloimonos, J. ER - TY - CHAP T1 - Polydioptric Cameras: New Eyes for Structure from Motion T2 - Pattern RecognitionPattern Recognition Y1 - 2002 A1 - Neumann, Jan A1 - Fermüller, Cornelia A1 - Aloimonos, J. ED - Van Gool,Luc AB - We examine the influence of camera design on the estimation of the motion and structure of a scene from video data. Every camera captures a subset of the light rays passing though some volume in space. By relating the differential structure of the time varying space of light rays to different known and new camera designs, we can establish a hierarchy of cameras. This hierarchy is based upon the stability and complexity of the computations necessary to estimate structure and motion. At the low end of this hierarchy is the standard planar pinhole camera for which the structure from motion problem is non-linear and ill-posed. At the high end is a camera, which we call the full field of view polydioptric camera, for which the problem is linear and stable. We develop design suggestions for the polydioptric camera, and based upon this new design we propose a linear algorithm for structure-from-motion estimation, which combines differential motion estimation with differential stereo. JA - Pattern RecognitionPattern Recognition T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 2449 SN - 978-3-540-44209-7 UR - http://dx.doi.org/10.1007/3-540-45783-6_74 ER - TY - JOUR T1 - A Probabilistic Clustering-Based Indoor Location Determination System JF - Technical Reports from UMIACS, UMIACS-TR-2002-30 Y1 - 2002 A1 - Youssef,Moustafa A A1 - Agrawala, Ashok K. A1 - A. Udaya Shankar A1 - Noh,Sam H KW - Technical Report AB - We present an indoor location determination system based on signalstrength probability distributions for tackling the noisy wireless channel and clustering to reduce computation requirements. We provide two implementation techniques, namely, Joint Clustering and Incremental Triangulation and describe their tradeoffs in terms of location determination accuracy and computation requirement. Both techniques have been incorporated in two implemented context-aware systems: User Positioning System and the Rover System, both running on Compaq iPAQ Pocket PC's with Familiar distribution of Linux for PDA's. The results obtained show that both techniques give the user location with over 90% accuracy to within 7 feet with very low computation requirements, hence enabling a set of context-aware applications. Also UMIACS-TR-2002-30 UR - http://drum.lib.umd.edu/handle/1903/1192 ER - TY - JOUR T1 - Processing large-scale multi-dimensional data in parallel and distributed environments JF - Parallel Computing Y1 - 2002 A1 - Beynon,Michael A1 - Chang,Chialin A1 - Catalyurek,Umit A1 - Kurc,Tahsin A1 - Sussman, Alan A1 - Andrade,Henrique A1 - Ferreira,Renato A1 - Saltz,Joel KW - Data-intensive applications KW - Distributed computing KW - Multi-dimensional datasets KW - PARALLEL PROCESSING KW - Runtime systems AB - Analysis of data is an important step in understanding and solving a scientific problem. Analysis involves extracting the data of interest from all the available raw data in a dataset and processing it into a data product. However, in many areas of science and engineering, a scientist's ability to analyze information is increasingly becoming hindered by dataset sizes. The vast amount of data in scientific datasets makes it a difficult task to efficiently access the data of interest, and manage potentially heterogeneous system resources to process the data. Subsetting and aggregation are common operations executed in a wide range of data-intensive applications. We argue that common runtime and programming support can be developed for applications that query and manipulate large datasets. This paper presents a compendium of frameworks and methods we have developed to support efficient execution of subsetting and aggregation operations in applications that query and manipulate large, multi-dimensional datasets in parallel and distributed computing environments. VL - 28 SN - 0167-8191 UR - http://www.sciencedirect.com/science/article/pii/S0167819102000972 CP - 5 M3 - 10.1016/S0167-8191(02)00097-2 ER - TY - JOUR T1 - Ray interpolants for fast raytracing reflections and refractions JF - Journal of WSCG (Proc. International Conf. in Central Europe on Comp. Graph., Visualization and Comp. Vision) Y1 - 2002 A1 - Atalay,F. B A1 - Mount, Dave AB - To render an object by ray tracing, one or more rays are shot from the viewpoint through every pixel ofthe image plane. For reflective and refractive objects, especially for multiple levels of reflections and/or refractions, this requires many expensive intersection calculations. This paper presents a new method for accelerating ray-tracing of reflective and refractive objects by substituting accurate-but-slow intersection calculations with approximate-but-fast interpolation computations. Our approach is based on modeling the reflective/refractive object as a function that maps input rays entering the object to output rays exiting the object. We are interested in computing the output ray without actually tracing the input ray through the object. This is achieved by adaptively sampling rays from multiple viewpoints in various directions, as a preprocessing phase, and then interpolating the collection of nearby samples to compute an approximate output ray for any input ray. In most cases, object boundaries and other discontinuities are handled by ap- plying various heuristics. In cases where we cannot find sufficient evidence to interpolate, we perform ray tracing as a last resort. We provide performance studies to demonstrate the efficiency of this method. VL - 10 CP - 3 ER - TY - JOUR T1 - Rover: scalable location-aware computing JF - Computer Y1 - 2002 A1 - Banerjee,S. A1 - Agarwal,S. A1 - Kamel,K. A1 - Kochut, A. A1 - Kommareddy,C. A1 - Nadeem,T. A1 - Thakkar,P. A1 - Trinh,Bao A1 - Youssef,A. A1 - Youssef, M. A1 - Larsen,R.L. A1 - Udaya Shankar,A. A1 - Agrawala, Ashok K. KW - amusement KW - application-specific KW - architecture; KW - automation; KW - business KW - business; KW - computing; KW - data KW - entertainment; KW - handheld KW - humanities; KW - integration KW - LAN; KW - location-aware KW - malls; KW - mobile KW - museums; KW - office KW - parks; KW - processing; KW - resource KW - Rover; KW - scalability; KW - scalable KW - scheduling; KW - shopping KW - software KW - system KW - theme KW - units; KW - user; KW - wireless AB - All the components necessary for realizing location-aware computing are available in the marketplace today. What has hindered the widespread deployment of location-based systems is the lack of an integration architecture that scales with user populations. The authors have completed the initial implementation of Rover, a system designed to achieve this sort of integration and to automatically tailor information and services to a mobile user's location. Their studies have validated Rover's underlying software architecture, which achieves system scalability through high-resolution, application-specific resource scheduling at the servers and network. The authors believe that this technology will greatly enhance the user experience in many places, including museums, amusement and theme parks, shopping malls, game fields, offices, and business centers. They designed the system specifically to scale to large user populations and expect its benefits to increase with them. VL - 35 SN - 0018-9162 CP - 10 M3 - 10.1109/MC.2002.1039517 ER - TY - CONF T1 - Scheduling multiple data visualization query workloads on a shared memory machine T2 - Parallel and Distributed Processing Symposium., Proceedings International, IPDPS 2002, Abstracts and CD-ROM Y1 - 2002 A1 - Andrade,H. A1 - Kurc, T. A1 - Sussman, Alan A1 - Saltz, J. KW - Atomic force microscopy KW - Biomedical informatics KW - Computer science KW - Data analysis KW - data visualisation KW - Data visualization KW - datasets KW - deductive databases KW - digitized microscopy image browsing KW - directed graph KW - directed graphs KW - dynamic query scheduling model KW - Educational institutions KW - high workloads KW - image database KW - limited resources KW - multiple data visualization query workloads KW - multiple query optimization KW - performance KW - priority queue KW - Processor scheduling KW - Query processing KW - query ranking KW - Relational databases KW - scheduling KW - shared memory machine KW - shared memory systems KW - Virtual Microscope KW - visual databases AB - Query scheduling plays an important role when systems are faced with limited resources and high workloads. It becomes even more relevant for servers applying multiple query optimization techniques to batches of queries, in which portions of datasets as well as intermediate results are maintained in memory to speed up query evaluation. We present a dynamic query scheduling model based on a priority queue implementation using a directed graph and a strategy for ranking queries. We examine the relative performance of several ranking strategies on a shared-memory machine using two different versions of an application, called the Virtual Microscope, for browsing digitized microscopy images JA - Parallel and Distributed Processing Symposium., Proceedings International, IPDPS 2002, Abstracts and CD-ROM PB - IEEE SN - 0-7695-1573-8 M3 - 10.1109/IPDPS.2002.1015482 ER - TY - CONF T1 - Space-efficient approximate Voronoi diagrams T2 - Proceedings of the thiry-fourth annual ACM symposium on Theory of computing Y1 - 2002 A1 - Arya,Sunil A1 - Malamatos,Theocharis A1 - Mount, Dave AB - (MATH) Given a set $S$ of $n$ points in $\IR^d$, a {\em $(t,\epsilon)$-approximate Voronoi diagram (AVD)} is a partition of space into constant complexity cells, where each cell $c$ is associated with $t$ representative points of $S$, such that for any point in $c$, one of the associated representatives approximates the nearest neighbor to within a factor of $(1+\epsilon)$. Like the Voronoi diagram, this structure defines a spatial subdivision. It also has the desirable properties of being easy to construct and providing a simple and practical data structure for answering approximate nearest neighbor queries. The goal is to minimize the number and complexity of the cells in the AVD.(MATH) We assume that the dimension $d$ is fixed. Given a real parameter $\gamma$, where $2 \le \gamma \le 1/\epsilon$, we show that it is possible to construct a $(t,\epsilon)$-AVD consisting of \[O(n \epsilon^{\frac{d-1}{2}} \gamma^{\frac{3(d-1)}{2}} \log \gamma) \] cells for $t = O(1/(\epsilon \gamma)^{(d-1)/2})$. This yields a data structure of $O(n \gamma^{d-1} \log \gamma)$ space (including the space for representatives) that can answer $\epsilon$-NN queries in time $O(\log(n \gamma) + 1/(\epsilon \gamma)^{(d-1)/2})$. (Hidden constants may depend exponentially on $d$, but do not depend on $\epsilon$ or $\gamma$).(MATH) In the case $\gamma = 1/\epsilon$, we show that the additional $\log \gamma$ factor in space can be avoided, and so we have a data structure that answers $\epsilon$-approximate nearest neighbor queries in time $O(\log (n/\epsilon))$ with space $O(n/\epsilon^{d-1})$, improving upon the best known space bounds for this query time. In the case $\gamma = 2$, we have a data structure that can answer approximate nearest neighbor queries in $O(\log n + 1/\epsilon^{(d-1)/2})$ time using optimal $O(n)$ space. This dramatically improves the previous best space bound for this query time by a factor of $O(1/\epsilon^{(d-1)/2})$.(MATH) We also provide lower bounds on the worst-case number of cells assuming that cells are axis-aligned rectangles of bounded aspect ratio. In the important extreme cases $\gamma \in \{2, 1/\epsilon\}$, our lower bounds match our upper bounds asymptotically. For intermediate values of $\gamma$ we show that our upper bounds are within a factor of $O((1/\epsilon)^{(d-1)/2}\log \gamma)$ of the lower bound. JA - Proceedings of the thiry-fourth annual ACM symposium on Theory of computing T3 - STOC '02 PB - ACM CY - New York, NY, USA SN - 1-58113-495-9 UR - http://doi.acm.org/10.1145/509907.510011 M3 - 10.1145/509907.510011 ER - TY - JOUR T1 - Spatio-temporal stereo using multi-resolution subdivision surfaces JF - International Journal of Computer Vision Y1 - 2002 A1 - Neumann, J. A1 - Aloimonos, J. VL - 47 CP - 1 ER - TY - JOUR T1 - Symbol systems JF - Encyclopedia of Cognitive Science Y1 - 2002 A1 - Anderson,M. L A1 - Perlis, Don ER - TY - CONF T1 - Time-situated agency: Active logic and intention formation T2 - in: Workshop on Cognitive Agents, 25th German Conference on Artificial Intelligence Y1 - 2002 A1 - Anderson,M. L A1 - Josyula,D. P A1 - Okamoto,Y. A A1 - Perlis, Don JA - in: Workshop on Cognitive Agents, 25th German Conference on Artificial Intelligence ER - TY - CONF T1 - Topology inference from BGP routing dynamics T2 - Proceedings of the 2nd ACM SIGCOMM Workshop on Internet measurment Y1 - 2002 A1 - Andersen,David G. A1 - Feamster, Nick A1 - Bauer,Steve A1 - Balakrishnan,Hari AB - This paper describes a method of inferring logical relationships between network prefixes within an Autonomous System (AS) using only passive monitoring of BGP messages. By clustering these prefixes based upon similarities between their update times, we create a hierarchy linking the prefixes within the larger AS. We can frequently identify groups of prefixes routed to the same ISP Point of Presence (POP), despite the lack of identifying information in the BGP messages. Similarly, we observe disparate prefixes under common organizational control, or with long shared network paths. In addition to discovering interesting network characteristics, our passive method facilitates topology discovery by potentially reducing the number of active probes required in traditional traceroute-based Internet mapping mechanisms. JA - Proceedings of the 2nd ACM SIGCOMM Workshop on Internet measurment T3 - IMW '02 PB - ACM CY - New York, NY, USA SN - 1-58113-603-X UR - http://doi.acm.org/10.1145/637201.637239 M3 - 10.1145/637201.637239 ER - TY - CONF T1 - The use-mention distinction and its importance to HCI T2 - Proceedings of the Sixth Workshop on the Semantics and Pragmatics of Dialog Y1 - 2002 A1 - Anderson,M. L A1 - Okamoto,Y. A1 - Josyula,D. A1 - Perlis, Don JA - Proceedings of the Sixth Workshop on the Semantics and Pragmatics of Dialog ER - TY - JOUR T1 - Using independent auditors as intrusion detection systems JF - Information and Communications Security Y1 - 2002 A1 - Molina,J. A1 - Arbaugh, William A. ER - TY - JOUR T1 - Visual space-time geometry - A tool for perception and the imagination JF - Proceedings of the IEEE Y1 - 2002 A1 - Fermüller, Cornelia A1 - Baker, P. A1 - Aloimonos, J. KW - 3-D motion estimation KW - Buildings KW - Computer vision KW - Geometry KW - Graphics KW - Image sequences KW - Layout KW - Mathematical model KW - mathematical theory KW - model building KW - Motion estimation KW - multiple view geometry KW - multiple views KW - Navigation KW - optical flow KW - optical illusions KW - patch correspondence KW - Rendering (computer graphics) KW - Robotics and automation KW - Solid modeling KW - structure from motion KW - three-dimensional models KW - visual space-time AB - Although the fundamental ideas underlying research efforts in the field of computer vision have not radically changed in the past two decades, there has been a transformation in the way work in this field is conducted. This is primarily due to the emergence of a number of tools, of both a practical and a theoretical nature. One such tool, celebrated throughout the nineties, is the geometry of visual space-time. It is known under a variety of headings, such as multiple view geometry, structure from motion, and model building. It is a mathematical theory relating multiple views (images) of a scene taken at different viewpoints to three-dimensional models of the (possibly dynamic) scene. This mathematical theory gave rise to algorithms that take as input images (or video) and provide as output a model of the scene. Such algorithms are one of the biggest successes of the field and they have many applications in other disciplines, such as graphics (image-based rendering, motion capture) and robotics (navigation). One of the difficulties, however is that the current tools cannot yet be fully automated, and they do not provide very accurate results. More research is required for automation and high precision. During the past few years we have investigated a number of basic questions underlying the structure from motion problem. Our investigations resulted in a small number of principles that characterize the problem. These principles, which give rise to automatic procedures and point to new avenues for studying the next level of the structure from motion problem, are the subject of this paper. VL - 90 SN - 0018-9219 CP - 7 M3 - 10.1109/JPROC.2002.801440 ER - TY - JOUR T1 - Your 802.11 network has no clothes JF - IEEE Communications Magazine Y1 - 2002 A1 - Mishra,A. A1 - Shin,M. A1 - Arbaugh, William A. VL - 9 ER - TY - JOUR T1 - Animated heads: From 3d motion fields to action descriptions JF - Proceedings of the IFIP TC5/WG5 Y1 - 2001 A1 - Neumann, J. A1 - Fermüller, Cornelia A1 - Aloimonos, J. VL - 10 ER - TY - JOUR T1 - Automated design of sheet metal punches for bending multiple parts in a single setup JF - Robotics and Computer-Integrated Manufacturing Y1 - 2001 A1 - Alva,Ujval A1 - Gupta, Satyandra K. KW - Praess planning KW - Punch design KW - Sheet metal bending AB - Sheet metal bending is a process in which bends are formed using a combination of a punch and a die. A very large number of mechanical products such as furniture panels, shelves, cabinets, housing for electro-mechanical devices, etc. are created by using the sheet metal bending process. Bending tools need to satisfy the following two criteria: (1) tools should be able to withstand bending forces, and (2) tool shapes should be such that there is no tool-part interference. In this paper, we describe a methodology for automatically designing shapes of bending punches for bending multiple parts in a single setup. We create parametric geometric models of punches. These parametric models describe the family of possible punch shapes. Using the part geometry and parametric punch shape models, we automatically generated constraints on tool parameters that eliminate the possibility of part-tool interference. We use mixed-integer techniques to identify parameters of punch shapes that result in the maximum punch strength. Finally, we perform strength analysis of the designed punch shape using finite element analysis methods, to verify that the designed punch shape is capable of withstanding the bending forces. VL - 17 SN - 0736-5845 UR - http://www.sciencedirect.com/science/article/pii/S0736584500000351 CP - 1–2 M3 - 10.1016/S0736-5845(00)00035-1 ER - TY - BOOK T1 - Becoming a Scholar in the Digital Age Y1 - 2001 A1 - Duderstadt,James A1 - Arms,William A1 - Messina,Paul A1 - Ellisman,Mark A1 - Atkins,Daniel A1 - Fox,Edward A1 - Shneiderman, Ben A1 - Nissenbaum,Helen A1 - Lederberg,Joshua KW - bibtex-import KW - digital-library KW - dlbook PB - National Research Council ER - TY - CONF T1 - Entropy-preserving cuttings and space-efficient planar point location T2 - Proceedings of the twelfth annual ACM-SIAM symposium on Discrete algorithms Y1 - 2001 A1 - Arya,Sunil A1 - Malamatos,Theocharis A1 - Mount, Dave AB - Point location is the problem of preprocessing a planar polygonal subdivision S into a data structure in order to determine efficiently the cell of the subdivision that contains a given query point. Given the probabilities pz that the query point lies within each cell z ∈ S, a natural question is how to design such a structure so as to minimize the expected-case query time. The entropy H of the probability distribution is the dominant term in the lower bound on the expected-case search time. Clearly the number of edges n of the subdivision is a lower bound on the space required. There is no known approach that simultaneously achieves the goals of H + &Ogr;(H) query time and &Ogr;(n) space. In this paper we introduce entropy-preserving cuttings and show how to use them to achieve query time H + &Ogr;(H), using only &Ogr;(n log* n) space. JA - Proceedings of the twelfth annual ACM-SIAM symposium on Discrete algorithms T3 - SODA '01 PB - Society for Industrial and Applied Mathematics CY - Philadelphia, PA, USA SN - 0-89871-490-7 UR - http://dl.acm.org/citation.cfm?id=365411.365456 ER - TY - CONF T1 - Evolving columnar circuitry for lateral cortical inhibition T2 - Neural Networks, 2001. Proceedings. IJCNN'01. International Joint Conference on Y1 - 2001 A1 - Ayers,D. A1 - Reggia, James A. JA - Neural Networks, 2001. Proceedings. IJCNN'01. International Joint Conference on VL - 1 ER - TY - CHAP T1 - Eyes from Eyes T2 - 3D Structure from Images — SMILE 20003D Structure from Images — SMILE 2000 Y1 - 2001 A1 - Baker,Patrick A1 - Pless,Robert A1 - Fermüller, Cornelia A1 - Aloimonos, J. ED - Pollefeys,Marc ED - Van Gool,Luc ED - Zisserman,Andrew ED - Fitzgibbon,Andrew AB - We describe a family of new imaging systems, called Argus eyes, that consist of common video cameras arranged in some network. The system we built consists of six cameras arranged so that they sample different parts of the visual sphere. This system has the capability of very accurately estimating its own 3D motion and consequently estimating shape models from the individual videos. The reason is that inherent ambiguities of confusion between translation and rotation disappear in this case. We provide an algorithm and several experiments using real outdoor or indoor images demonstrating the superiority of the new sensor with regard to 3D motion estimation. JA - 3D Structure from Images — SMILE 20003D Structure from Images — SMILE 2000 T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 2018 SN - 978-3-540-41845-0 UR - http://dx.doi.org/10.1007/3-540-45296-6_14 ER - TY - BOOK T1 - Eyes from Eyes: Analysis of Camera Design Using Plenoptic Video Geometry Y1 - 2001 A1 - Neumann, J. A1 - Fermüller, Cornelia A1 - Aloimonos, J. A1 - University of Maryland (College Park, Md.). Center for Automation Research AB - We investigate the relationship between camera design and the problem of recovering the motion andstructure of a scene from video data. The visual information that could possibly be obtained is described by the plenoptic function. A camera can be viewed as a device that captures a subset of this function, that is, it measures some of the light rays in some part of the space. The information contained in the subset determines how difficult it is to solve subsequent interpretation processes. By examining the differential structure of the time varying plenoptic function we relate different known and new camera models to the spatio-temporal structure of the observed scene. This allows us to define a hierarchy of camera designs, where the order is determined by the stability and complexity of the computations necessary to estimate structure and motion. At the low end of this hierarchy is the standard planar pinhole camera for which the structure from motion problem is non-linear and ill-posed. At the high end is a camera, which we call the full field of view polydioptric camera, for which the problem is linear and stable. In between are multiple-view cameras with large fields of view which we have built, as well as catadioptric panoramic sensors and other omni-directional cameras. We develop design suggestions for the polydioptric camera, and based upon this new design we propose a linear algorithm for ego- motion estimation, which in essence combines differential motion estimation with differential stereo. PB - Computer Vision Laboratory, Center for Automation Research, University of Maryland ER - TY - CHAP T1 - Geometry of Eye Design: Biology and Technology T2 - Multi-Image Analysis Y1 - 2001 A1 - Fermüller, Cornelia A1 - Aloimonos, J. ED - Klette,Reinhard ED - Gimel’farb,Georgy ED - Huang,Thomas AB - Natural or artificial vision systems process the images that they collect with their eyes or cameras in order to derive information for performing tasks related to navigation and recognition. Since the way images are acquired determines how dificult it is to perform a visual task, and since systems have to cope with limited resources, the eyes used by a specific system should be designed to optimize subsequent image processing as it relates to particular tasks. Different ways of sampling light, i.e., different eyes, may be less or more powerful with respect to particular competences. This seems intuitively evident in view of the variety of eye designs in the biological world. It is shown here that a spherical eye (an eye or system of eyes providing panoramic vision) is superior to a camera-type eye (an eye with restricted field of view) as regards the competence of three-dimensional motion estimation. This result is derived from a statistical analysis of all the possible computational models that can be used for estimating 3D motion from an image sequence. The findings explain biological design in a mathematical manner, by showing that systems that fly and thus need good estimates of 3D motion gain advantages from panoramic vision. Also, insights obtained from this study point to new ways of constructing powerful imaging devices that suit particular tasks in robotics, visualization and virtual reality better than conventional cameras, thus leading to a new camera technology. JA - Multi-Image Analysis T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 2032 SN - 978-3-540-42122-1 UR - http://dx.doi.org/10.1007/3-540-45134-X_2 ER - TY - JOUR T1 - Operating Systems JF - Real-Time Systems Y1 - 2001 A1 - Agrawala, Ashok K. ER - TY - CONF T1 - Personal secure booting T2 - Information Security and Privacy Y1 - 2001 A1 - Itoi,N. A1 - Arbaugh, William A. A1 - Pollack,S. A1 - Reeves,D. JA - Information Security and Privacy ER - TY - JOUR T1 - The price of safety in an active network JF - Journal of Communications and Networks Y1 - 2001 A1 - Alexander,D. S A1 - Menage,P. B A1 - Keromytis,A. D A1 - Arbaugh, William A. A1 - Anagnostakis,K. G A1 - Smith,J. M VL - 3 CP - 1 ER - TY - JOUR T1 - Probabilistic temporal databases JF - ACM Transaction on Database Systems Y1 - 2001 A1 - Alex,D. A1 - Robert,R. A1 - V.S. Subrahmanian VL - 26 CP - 1 ER - TY - RPRT T1 - Revolutionary Advances in Ubiquitious, Real-Time Multicomputers and Runtime Environments Y1 - 2001 A1 - Agrawala, Ashok K. AB - This work was a grant to enhance the Maruti operating system in several ways, in order to provide Mississippi State with a platform upon which their work on the Real-Time Message Passing Interface could be developed. Key technical achievements: (1) Developed predictable Myrinet communications for use in a real-time NOW; (2) Developed the MSU-Kernel to provide a POSIX OS for real- time NOWs; (3) Developed and implemented an algorithm for deploying a globally synchronized clock in a real-time NOW; (4) Developed an improved real-time scheduler for the Maruti hard real-time operating system at University of Maryland (UMD); and (5) Introduced a new parametric approach in Maruti for dynamic scheduling at UMD. Details of the results of the work are presented in papers, thesis and project reports. PB - MISSISSIPPI STATE UNIVERSITY VL - A340293 ER - TY - CONF T1 - A simple entropy-based algorithm for planar point location T2 - Proceedings of the twelfth annual ACM-SIAM symposium on Discrete algorithms Y1 - 2001 A1 - Arya,Sunil A1 - Malamatos,Theocharis A1 - Mount, Dave AB - Given a planar polygonal subdivision S, point location involves preprocessing this subdivision into a data structure so that given any query point q, the cell of the subdivision containing q can be determined efficiently. Suppose that for each cell z in the subdivision, the probability pz that a query point lies within this cell is also given. The goal is to design the data structure to minimize the average search time. It has long been known that the entropy H of the probability distribution is the dominant term in the lower bound on the average-case search time. This problem has been considered before, but existing data structures are all quite complicated. In this paper, we show that a very simple modification of a well-known randomized incremental algorithm can be applied to produce a data structure of expected linear size that can answer point location queries in &Ogr;(H) average time. We also present empirical evidence for the practical efficiency of this approach. JA - Proceedings of the twelfth annual ACM-SIAM symposium on Discrete algorithms T3 - SODA '01 PB - Society for Industrial and Applied Mathematics CY - Philadelphia, PA, USA SN - 0-89871-490-7 UR - http://dl.acm.org/citation.cfm?id=365411.365457 ER - TY - CONF T1 - A spherical eye from multiple cameras (makes better models of the world) T2 - Proceedings of the 2001 IEEE Computer Society Conference on Computer Vision and Pattern Recognition, 2001. CVPR 2001 Y1 - 2001 A1 - Baker, P. A1 - Fermüller, Cornelia A1 - Aloimonos, J. A1 - Pless, R. KW - 3D motion estimation KW - Calibration KW - camera network KW - CAMERAS KW - Computer vision KW - egomotion recovery KW - geometric configuration KW - geometric constraint KW - image gradients KW - image sampling KW - imaging system KW - Laboratories KW - Layout KW - Motion estimation KW - multiple cameras KW - Pixel KW - Robot vision systems KW - SHAPE KW - shape models KW - Space technology KW - spherical eye KW - system calibration KW - video KW - video cameras KW - video signal processing KW - visual sphere sampling AB - The paper describes an imaging system that has been designed specifically for the purpose of recovering egomotion and structure from video. The system consists of six cameras in a network arranged so that they sample different parts of the visual sphere. This geometric configuration has provable advantages compared to small field of view cameras for the estimation of the system's own motion and consequently the estimation of shape models from the individual cameras. The reason is that inherent ambiguities of confusion between translation and rotation disappear. We provide algorithms for the calibration of the system and 3D motion estimation. The calibration is based on a new geometric constraint that relates the images of lines parallel in space to the rotation between the cameras. The 3D motion estimation uses a constraint relating structure directly to image gradients. JA - Proceedings of the 2001 IEEE Computer Society Conference on Computer Vision and Pattern Recognition, 2001. CVPR 2001 PB - IEEE VL - 1 SN - 0-7695-1272-0 M3 - 10.1109/CVPR.2001.990525 ER - TY - CHAP T1 - Statistics Explains Geometrical Optical Illusions T2 - Foundations of Image UnderstandingFoundations of Image Understanding Y1 - 2001 A1 - Fermüller, Cornelia A1 - Aloimonos, J. ED - Davis, Larry S. AB - Azriel Rosenfeld has been our mentor for the last decade. In everyday conversation he stressed the importance of intuition, the unreasonable effectiveness of mathematics in understanding the world, and the power of simplicity inherent in deep ideas. Because we mostly worked on 3D vision, he often argued that 2D vision has been, is, and will continue to be a large source of problems. Strangely enough, we arrived at this study, which is our first on 2D vision, through problems we encountered in our work in 3D motion and shape. Azriel Rosenfeld was also one of the first to apply statistics [ 27 , 28 ] to image analysis and understanding, and he always reminded us of the uncertainties involved in visual computations. This paper shows that statistics cannot be ignored, not even in the interpretation of two simple straight intersecting lines. It demonstrates that uncertainty in the visual data causes problems for the early visual processes. Because of noise, the estimation of features, such as lines, intersections of lines, and local image motion, is biased. The inevitability of this bias provides an explanation for many well-known geometrical optical illusions. JA - Foundations of Image UnderstandingFoundations of Image Understanding T3 - The Kluwer International Series in Engineering and Computer Science PB - Springer US VL - 628 SN - 978-1-4615-1529-6 UR - http://dx.doi.org/10.1007/978-1-4615-1529-6_14 ER - TY - JOUR T1 - The Statistics of Optical Flow JF - Computer Vision and Image Understanding Y1 - 2001 A1 - Fermüller, Cornelia A1 - Shulman,David A1 - Aloimonos, J. AB - When processing image sequences some representation of image motion must be derived as a first stage. The most often used representation is the optical flow field, which is a set of velocity measurements of image patterns. It is well known that it is very difficult to estimate accurate optical flow at locations in an image which correspond to scene discontinuities. What is less well known, however, is that even at the locations corresponding to smooth scene surfaces, the optical flow field often cannot be estimated accurately.Noise in the data causes many optical flow estimation techniques to give biased flow estimates. Very often there is consistent bias: the estimate tends to be an underestimate in length and to be in a direction closer to the majority of the gradients in the patch. This paper studies all three major categories of flow estimation methods—gradient-based, energy-based, and correlation methods, and it analyzes different ways of compounding one-dimensional motion estimates (image gradients, spatiotemporal frequency triplets, local correlation estimates) into two-dimensional velocity estimates, including linear and nonlinear methods. Correcting for the bias would require knowledge of the noise parameters. In many situations, however, these are difficult to estimate accurately, as they change with the dynamic imagery in unpredictable and complex ways. Thus, the bias really is a problem inherent to optical flow estimation. We argue that the bias is also integral to the human visual system. It is the cause of the illusory perception of motion in the Ouchi pattern and also explains various psychophysical studies of the perception of moving plaids. VL - 82 SN - 1077-3142 UR - http://www.sciencedirect.com/science/article/pii/S1077314200909007 CP - 1 M3 - 10.1006/cviu.2000.0900 ER - TY - CONF T1 - Towards the ultimate motion capture technology T2 - Deformable avatars: IFIP TC5/WG5. 10 DEFORM'2000 Workshop, November 29-30, 2000, Geneva, Switzerland and AVATARS'2000 Workshop, November 30-December 1, 2000, Lausanne, Switzerland Y1 - 2001 A1 - Stuart, B. A1 - Baker, P. A1 - Aloimonos, J. JA - Deformable avatars: IFIP TC5/WG5. 10 DEFORM'2000 Workshop, November 29-30, 2000, Geneva, Switzerland and AVATARS'2000 Workshop, November 30-December 1, 2000, Lausanne, Switzerland VL - 68 ER - TY - CONF T1 - A trend analysis of exploitations T2 - 2001 IEEE Symposium on Security and Privacy, 2001. S&P 2001. Proceedings Y1 - 2001 A1 - Browne,H. K A1 - Arbaugh, William A. A1 - McHugh,J. A1 - Fithen,W. L KW - Computer science KW - computer security exploits KW - Data analysis KW - data mining KW - Educational institutions KW - exploitations KW - Performance analysis KW - Predictive models KW - Regression analysis KW - Risk management KW - security of data KW - software engineering KW - system intrusions KW - System software KW - trend analysis KW - vulnerabilities KW - vulnerability exploitation AB - We have conducted an empirical study of a number of computer security exploits and determined that the rates at which incidents involving the exploit are reported to CERT can be modeled using a common mathematical framework. Data associated with three significant exploits involving vulnerabilities in phf, imap, and bind can all be modeled using the formula C=I+S×√M where C is the cumulative count of reported incidents, M is the time since the start of the exploit cycle, and I and S are the regression coefficients determined by analysis of the incident report data. Further analysis of two additional exploits involving vulnerabilities in mountd and statd confirm the model. We believe that the models will aid in predicting the severity of subsequent vulnerability exploitations, based on the rate of early incident reports JA - 2001 IEEE Symposium on Security and Privacy, 2001. S&P 2001. Proceedings PB - IEEE SN - 0-7695-1046-9 M3 - 10.1109/SECPRI.2001.924300 ER - TY - CHAP T1 - Analyzing Action Representations T2 - Algebraic Frames for the Perception-Action CycleAlgebraic Frames for the Perception-Action Cycle Y1 - 2000 A1 - Aloimonos, J. A1 - Fermüller, Cornelia ED - Sommer,Gerald ED - Zeevi,Yehoshua AB - We argue that actions represent the basic seed of intelligence underlying perception of the environment, and the representations encoding actions should be the starting point upon which further studies of cognition are built. In this paper we make a first effort in characterizing these action representations. In particular, from the study of simple actions related to 3D rigid motion interpretation, we deduce a number of principles for the possible computations responsible for the interpretation of space-time geometry. Using these principles, we then discuss possible avenues on how to proceed in analyzing the representations of more complex human actions. JA - Algebraic Frames for the Perception-Action CycleAlgebraic Frames for the Perception-Action Cycle T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 1888 SN - 978-3-540-41013-3 UR - http://dx.doi.org/10.1007/10722492_1 ER - TY - JOUR T1 - Approximate range searching JF - Computational Geometry Y1 - 2000 A1 - Arya,Sunil A1 - Mount, Dave KW - Approximation algorithms KW - Box-decomposition trees KW - Partition trees KW - Range searching AB - The range searching problem is a fundamental problem in computational geometry, with numerous important applications. Most research has focused on solving this problem exactly, but lower bounds show that if linear space is assumed, the problem cannot be solved in polylogarithmic time, except for the case of orthogonal ranges. In this paper we show that if one is willing to allow approximate ranges, then it is possible to do much better. In particular, given a bounded range Q of diameter w and ε>0, an approximate range query treats the range as a fuzzy object, meaning that points lying within distance εw of the boundary of Q either may or may not be counted. We show that in any fixed dimension d, a set of n points in Rd can be preprocessed in O(n+logn) time and O(n) space, such that approximate queries can be answered in O(logn(1/ε)d) time. The only assumption we make about ranges is that the intersection of a range and a d-dimensional cube can be answered in constant time (depending on dimension). For convex ranges, we tighten this to O(logn+(1/ε)d−1) time. We also present a lower bound for approximate range searching based on partition trees of Ω(logn+(1/ε)d−1), which implies optimality for convex ranges (assuming fixed dimensions). Finally, we give empirical evidence showing that allowing small relative errors can significantly improve query execution times. VL - 17 SN - 0925-7721 UR - http://www.sciencedirect.com/science/article/pii/S0925772100000225 CP - 3–4 M3 - 10.1016/S0925-7721(00)00022-5 ER - TY - CONF T1 - Automated design of sheet metal bending tools Y1 - 2000 A1 - Alva,U. A1 - Gupta,S.K. A1 - Gupta,R. K. AB - Sheet metal bending is a process in which bends are formed using a combination of apunch and a die. Bending tools need to satisfy the following two criteria: (1) tools should be able to withstand bending forces, and (2) tool shapes should be such that there is no tool-part interference. In this paper, we describe a systematic methodology for automatically synthesizing a punch shape that can be used to produce more than one type of part. We create a parametric geometric model of possible punches. This parametric model describes a family of possible punch shapes. Using the geometric models of various given part types and a parametric punch model, we automatically generate constraints on punch parameters that eliminate the possibility of part-tool interference. We use mixed integer programming techniques to solve these constraints and identify parameters of a punch shape that can work for the given set of parts. Finally, we perform strength analysis of the designed punch to verify that the designed punch is capable of withstanding the bending forces. UR - http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.34.5031&rep=rep1&type=pdf ER - TY - CONF T1 - Cortical inhibition as explained by the competitive distribution hypothesis T2 - Network models for control and processing Y1 - 2000 A1 - Reggia, James A. A1 - Sutton III,G. G. A1 - Lynne,C. A1 - D'Autrechy,S. C A1 - Armentrout,S. L JA - Network models for control and processing ER - TY - CONF T1 - Designing StoryRooms: interactive storytelling spaces for children T2 - Proceedings of the 3rd conference on Designing interactive systems: processes, practices, methods, and techniques Y1 - 2000 A1 - Alborzi,H. A1 - Druin, Allison A1 - Montemayor,J. A1 - Platner,M. A1 - Porteous,J. A1 - Sherman,L. A1 - Boltman,A. A1 - Taxén,G. A1 - Best,J. A1 - Hammer,J. A1 - others JA - Proceedings of the 3rd conference on Designing interactive systems: processes, practices, methods, and techniques ER - TY - JOUR T1 - Detecting independent motion: The statistics of temporal continuity JF - Pattern Analysis and Machine Intelligence, IEEE Transactions on Y1 - 2000 A1 - Pless, R. A1 - Brodsky, T. A1 - Aloimonos, J. VL - 22 CP - 8 ER - TY - CONF T1 - A dual interpretation of “standard constraints” in parametric scheduling T2 - Formal Techniques in Real-Time and Fault-Tolerant Systems Y1 - 2000 A1 - Subramani,K. A1 - Agrawala, Ashok K. AB - Parametric scheduling in real-time systems, in the presence of linear relative constraints between the start and execution times of tasks, is a well-studied problem. Prior research established the existence of polynomial time algorithms for the case when the constraints are restricted to be standard and the execution time vectors belong to an axis-parallel hyper-rectangle. In this paper we present a polynomial time algorithm for the case when the execution time vectors belong to arbitrary convex domains. Our insights into the problem occur primarily as a result of studying the dual polytope of the constraint system. JA - Formal Techniques in Real-Time and Fault-Tolerant Systems ER - TY - JOUR T1 - Efficient expected-case algorithms for planar point location JF - Algorithm Theory-SWAT 2000 Y1 - 2000 A1 - Arya,S. A1 - Cheng,S. W A1 - Mount, Dave A1 - Ramesh,H. M3 - 10.1007/3-540-44985-X_31 ER - TY - JOUR T1 - Efficiently computing and updating triangle strips for real-time rendering JF - Computer Aided Design Y1 - 2000 A1 - El-Sana,J. A1 - Evans,F. A1 - Kalaiah,A. A1 - Varshney, Amitabh A1 - Skiena,S. A1 - Azanli,E. AB - Triangle strips are a widely used hardware-supported data-structure to compactly represent and efficiently render polygonal meshes. In thispaper we survey the efficient generation of triangle strips as well as their variants. We present efficient algorithms for partitioning polygonal meshes into triangle strips. Triangle strips have traditionally used a buffer size of two vertices. In this paper we also study the impact of larger buffer sizes and various queuing disciplines on the effectiveness of triangle strips. View-dependent simplification has emerged as a powerful tool for graphics acceleration in visualization of complex environments. However, in a view-dependent framework the triangle mesh connectivity changes at every frame making it difficult to use triangle strips. In this paper we present a novel data-structure, Skip Strip, that efficiently maintains triangle strips during such view-dependent changes. A Skip Strip stores the vertex hierarchy nodes in a skip-list-like manner with path compression. We anticipate that Skip Strips will provide a road-map to combine rendering acceleration techniques for static datasets, typical of retained-mode graphics applications, with those for dynamic datasets found in immediate-mode applications. VL - 32 CP - 13 ER - TY - CONF T1 - A first step towards automated detection of buffer overrun vulnerabilities T2 - The 2000 Network and Distributed Systems Security Conference. San Diego, CA Y1 - 2000 A1 - Wagner,D. A1 - Foster, Jeffrey S. A1 - Brewer,E.A. A1 - Aiken,A. JA - The 2000 Network and Distributed Systems Security Conference. San Diego, CA VL - 14 ER - TY - JOUR T1 - The genome sequence of Drosophila melanogaster JF - Science Y1 - 2000 A1 - Adams,M.D. A1 - Celniker,S.E. A1 - Holt,R.A. A1 - Evans,C.A. A1 - Gocayne,J.D. A1 - Amanatides,P.G. A1 - Scherer,S.E. A1 - Li,P.W. A1 - Hoskins,R.A. A1 - Galle,R.F. A1 - others AB - The fly Drosophila melanogaster is one of the most intensively studied organisms in biology and serves as a model system for the investigation of many developmental and cellular processes common to higher eukaryotes, including humans. We have determined the nucleotide sequence of nearly all of the ∼120-megabase euchromatic portion of theDrosophila genome using a whole-genome shotgun sequencing strategy supported by extensive clone-based sequence and a high-quality bacterial artificial chromosome physical map. Efforts are under way to close the remaining gaps; however, the sequence is of sufficient accuracy and contiguity to be declared substantially complete and to support an initial analysis of genome structure and preliminary gene annotation and interpretation. The genome encodes ∼13,600 genes, somewhat fewer than the smaller Caenorhabditis elegansgenome, but with comparable functional diversity. VL - 287 SN - 0036-8075, 1095-9203 UR - http://www.sciencemag.org/content/287/5461/2185 CP - 5461 M3 - 10.1126/science.287.5461.2185 ER - TY - JOUR T1 - A model for magnetic aftereffect in the presence of time varying demagnetizing fields JF - Magnetics, IEEE Transactions on Y1 - 2000 A1 - Korman,C.E. A1 - Adly,A.A. A1 - Mayergoyz, Issak D A1 - Rugkwamsook,P. KW - aftereffect; KW - aftereffect;magnetization;numerical KW - demagnetizing KW - field;demagnetisation;magnetic KW - model;magnetic KW - Preisach KW - relaxation;time KW - simulation;thermal KW - varying AB - Preisach models driven by stochastic inputs are employed to model magnetic aftereffect in the presence of demagnetizing fields. As a result of thermal relaxation, the magnetization and, consequently, the demagnetizing field vary in time. The new model generalizes earlier work and self-consistently accounts for the effect of time varying demagnetizing fields on the relaxation process. Three practical numerical techniques are proposed to compute the time variation in the magnetic field and the state of the Preisach plane VL - 36 SN - 0018-9464 CP - 5 M3 - 10.1109/20.908729 ER - TY - CONF T1 - Multi-camera networks: eyes from eyes T2 - IEEE Workshop on Omnidirectional Vision, 2000. Proceedings Y1 - 2000 A1 - Fermüller, Cornelia A1 - Aloimonos, J. A1 - Baker, P. A1 - Pless, R. A1 - Neumann, J. A1 - Stuart, B. KW - Biosensors KW - CAMERAS KW - Computer vision KW - Eyes KW - Image sequences KW - intelligent systems KW - Layout KW - Machine vision KW - Robot vision systems KW - Robustness KW - Spatiotemporal phenomena KW - video cameras KW - Virtual reality AB - Autonomous or semi-autonomous intelligent systems, in order to function appropriately, need to create models of their environment, i.e., models of space time. These are descriptions of objects and scenes and descriptions of changes of space over time, that is, events and actions. Despite the large amount of research on this problem, as a community we are still far from developing robust descriptions of a system's spatiotemporal environment using video input (image sequences). Undoubtedly, some progress has been made regarding the understanding of estimating the structure of visual space, but it has not led to solutions to specific applications. There is, however, an alternative approach which is in line with today's “zeitgeist.” The vision of artificial systems can be enhanced by providing them with new eyes. If conventional video cameras are put together in various configurations, new sensors can be constructed that have much more power and the way they “see” the world makes it much easier to solve problems of vision. This research is motivated by examining the wide variety of eye design in the biological world and obtaining inspiration for an ensemble of computational studies that relate how a system sees to what that system does (i.e. relating perception to action). This, coupled with the geometry of multiple views that has flourished in terms of theoretical results in the past few years, points to new ways of constructing powerful imaging devices which suit particular tasks in robotics, visualization, video processing, virtual reality and various computer vision applications, better than conventional cameras. This paper presents a number of new sensors that we built using common video cameras and shows their superiority with regard to developing models of space and motion JA - IEEE Workshop on Omnidirectional Vision, 2000. Proceedings PB - IEEE SN - 0-7695-0704-2 M3 - 10.1109/OMNVIS.2000.853797 ER - TY - CONF T1 - Nearly optimal expected-case planar point location T2 - Foundations of Computer Science, 2000. Proceedings. 41st Annual Symposium on Y1 - 2000 A1 - Arya,S. A1 - Malamatos,T. A1 - Mount, Dave KW - computational geometry KW - convex cells KW - data structure KW - expected search time KW - nearly optimal expected-case planar point location KW - optimal binary search tree KW - planar point location KW - planar polygonal subdivision KW - polygonal cells KW - polygonal subdivision KW - probability KW - search problems KW - search structure KW - subdivision KW - trees (mathematics) AB - We consider the planar point location problem from the perspective of expected search time. We are given a planar polygonal subdivision S and for each polygon of the subdivision the probability that a query point lies within this polygon. The goal is to compute a search structure to determine which cell of the subdivision contains a given query point, so as to minimize the expected search time. This is a generalization of the classical problem of computing an optimal binary search tree for one-dimensional keys. In the one-dimensional case it has long been known that the entropy H of the distribution is the dominant term in the lower bound on the expected-case search time, and further there exist search trees achieving expected search times of at most H+2. Prior to this work, there has been no known structure for planar point location with an expected search time better than 2H, and this result required strong assumptions on the nature of the query point distribution. Here we present a data structure whose expected search time is nearly equal to the entropy lower bound, namely H+o(H). The result holds for any polygonal subdivision in which the number of sides of each of the polygonal cells is bounded, and there are no assumptions on the query distribution within each cell. We extend these results to subdivisions with convex cells, assuming a uniform query distribution within each cell JA - Foundations of Computer Science, 2000. Proceedings. 41st Annual Symposium on M3 - 10.1109/SFCS.2000.892108 ER - TY - JOUR T1 - New eyes for building models from video JF - Computational Geometry Y1 - 2000 A1 - Fermüller, Cornelia A1 - Aloimonos, J. A1 - Brodský,Tomáš KW - model building KW - shape reconstruction KW - structure from motion KW - video analysis AB - Models of real-world objects and actions for use in graphics, virtual and augmented reality and related fields can only be obtained through the use of visual data and particularly video. This paper examines the question of recovering shape models from video information. Given video of an object or a scene captured by a moving camera, a prerequisite for model building is to recover the three-dimensional (3D) motion of the camera which consists of a rotation and a translation at each instant. It is shown here that a spherical eye (an eye or system of eyes providing panoramic vision) is superior to a camera-type eye (an eye with restricted field of view such as a common video camera) as regards the competence of 3D motion estimation. This result is derived from a geometric/statistical analysis of all the possible computational models that can be used for estimating 3D motion from an image sequence. Regardless of the estimation procedure for a camera-type eye, the parameters of the 3D rigid motion (translation and rotation) contain errors satisfying specific geometric constraints. Thus, translation is always confused with rotation, resulting in inaccurate results. This confusion does not happen for the case of panoramic vision. Insights obtained from this study point to new ways of constructing powerful imaging devices that suit particular tasks in visualization and virtual reality better than conventional cameras, thus leading to a new camera technology. Such new eyes are constructed by putting together multiple existing video cameras in specific ways, thus obtaining eyes from eyes. For a new eye of this kind we describe an implementation for deriving models of scenes from video data, while avoiding the correspondence problem in the video sequence. VL - 15 SN - 0925-7721 UR - http://www.sciencedirect.com/science/article/pii/S0925772199000449 CP - 1–3 M3 - 10.1016/S0925-7721(99)00044-9 ER - TY - CHAP T1 - New Eyes for Shape and Motion Estimation T2 - Biologically Motivated Computer VisionBiologically Motivated Computer Vision Y1 - 2000 A1 - Baker,Patrick A1 - Pless,Robert A1 - Fermüller, Cornelia A1 - Aloimonos, J. ED - Lee,Seong-Whan ED - Bülthoff,Heinrich ED - Poggio,Tomaso AB - Motivated by the full field of view of insect eyes and their fast and accurate estimation of egomotion, we constructed a system of cameras to take advantage of the full field of view (FOV) constraints that insects use. In this paper, we develop a new ego-motion algorithm for a rigidly mounted set of cameras undergoing arbitrary rigid motion. This egomotion algorithm combines the unambiguous components of the motion computed by each separate camera. We prove that the cyclotorsion is resistant to errors and show this empirically. We show how to calibrate the system with two novel algorithms, one using secondary cameras and one using self calibration. Given this system calibration, the new 3D motion algorithm first computes the rotation and then the 3D translation. We apply this algorithm to a camera system constructed with four rigidly mounted synchronized cameras pointing in various directions and present motion estimation results at www.cfar.umd.edu/ pbaker/argus.html. JA - Biologically Motivated Computer VisionBiologically Motivated Computer Vision T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 1811 SN - 978-3-540-67560-0 UR - http://dx.doi.org/10.1007/3-540-45482-9_12 ER - TY - CONF T1 - A New Framework for Multi-camera Structure from Motion T2 - Mustererkennung 2000, 22. DAGM-Symposium Y1 - 2000 A1 - Neumann, J. A1 - Fermüller, Cornelia A1 - Aloimonos, J. JA - Mustererkennung 2000, 22. DAGM-Symposium ER - TY - JOUR T1 - Observability of 3D Motion JF - International Journal of Computer Vision Y1 - 2000 A1 - Fermüller, Cornelia A1 - Aloimonos, J. AB - This paper examines the inherent difficulties in observing 3D rigid motion from image sequences. It does so without considering a particular estimator. Instead, it presents a statistical analysis of all the possible computational models which can be used for estimating 3D motion from an image sequence. These computational models are classified according to the mathematical constraints that they employ and the characteristics of the imaging sensor (restricted field of view and full field of view). Regarding the mathematical constraints, there exist two principles relating a sequence of images taken by a moving camera. One is the “epipolar constraint,” applied to motion fields, and the other the “positive depth” constraint, applied to normal flow fields. 3D motion estimation amounts to optimizing these constraints over the image. A statistical modeling of these constraints leads to functions which are studied with regard to their topographic structure, specifically as regards the errors in the 3D motion parameters at the places representing the minima of the functions. For conventional video cameras possessing a restricted field of view, the analysis shows that for algorithms in both classes which estimate all motion parameters simultaneously, the obtained solution has an error such that the projections of the translational and rotational errors on the image plane are perpendicular to each other. Furthermore, the estimated projection of the translation on the image lies on a line through the origin and the projection of the real translation. The situation is different for a camera with a full (360 degree) field of view (achieved by a panoramic sensor or by a system of conventional cameras). In this case, at the locations of the minima of the above two functions, either the translational or the rotational error becomes zero, while in the case of a restricted field of view both errors are non-zero. Although some ambiguities still remain in the full field of view case, the implication is that visual navigation tasks, such as visual servoing, involving 3D motion estimation are easier to solve by employing panoramic vision. Also, the analysis makes it possible to compare properties of algorithms that first estimate the translation and on the basis of the translational result estimate the rotation, algorithms that do the opposite, and algorithms that estimate all motion parameters simultaneously, thus providing a sound framework for the observability of 3D motion. Finally, the introduced framework points to new avenues for studying the stability of image-based servoing schemes. VL - 37 SN - 0920-5691 UR - http://dx.doi.org/10.1023/A:1008177429387 CP - 1 ER - TY - CONF T1 - Optimal design of signaling networks for Internet telephony T2 - IEEE INFOCOM 2000. Nineteenth Annual Joint Conference of the IEEE Computer and Communications Societies. Proceedings Y1 - 2000 A1 - Srinivasan, Aravind A1 - Ramakrishnan,K. G A1 - Kumaran,K. A1 - Aravamudan,M. A1 - Naqvi,S. KW - bandwidth allocation KW - Computational efficiency KW - Computer networks KW - Cost function KW - Demand forecasting KW - demand forecasts KW - graph theory KW - graphical design tool KW - Internet telephony KW - Linear programming KW - Load forecasting KW - Load management KW - Network topology KW - optimal design KW - optimal load balancing KW - optimisation KW - performance KW - quadratic assignment problem KW - random graphs KW - randomised algorithms KW - randomized heuristics KW - Signal design KW - signaling networks KW - Switches KW - telecommunication signalling KW - topology design AB - We present an approach for efficient design of a signaling network for a network of software switches supporting Internet telephony. While one may take an integer programming approach to solve this problem, it quickly becomes intractable even for modest-sized networks. Instead, our topology design uses random graphs that we show to be nearly optimal in cost, highly connected, and computationally efficient even for large networks. We then formulate a quadratic assignment problem (QAP) to map the abstract topology into the physical network to achieve optimal load balancing for given demand forecasts, which we solve using randomized heuristics. Numerical results on several example networks illustrate the performance and computational efficiency of our method. A graphical design tool has been developed based on our algorithms JA - IEEE INFOCOM 2000. Nineteenth Annual Joint Conference of the IEEE Computer and Communications Societies. Proceedings PB - IEEE VL - 2 SN - 0-7803-5880-5 M3 - 10.1109/INFCOM.2000.832245 ER - TY - JOUR T1 - The Ouchi illusion as an artifact of biased flow estimation JF - Vision Research Y1 - 2000 A1 - Fermüller, Cornelia A1 - Pless,Robert A1 - Aloimonos, J. KW - Bias KW - MOTION KW - optical flow KW - Plaid KW - Statistics AB - A pattern by Ouchi has the surprising property that small motions can cause illusory relative motion between the inset and background regions. The effect can be attained with small retinal motions or a slight jiggling of the paper and is robust over large changes in the patterns, frequencies and boundary shapes. In this paper, we explain that the cause of the illusion lies in the statistical difficulty of integrating local one-dimensional motion signals into two-dimensional image velocity measurements. The estimation of image velocity generally is biased, and for the particular spatial gradient distributions of the Ouchi pattern the bias is highly pronounced, giving rise to a large difference in the velocity estimates in the two regions. The computational model introduced to describe the statistical estimation of image velocity also accounts for the findings of psychophysical studies with variations of the Ouchi pattern and for various findings on the perception of moving plaids. The insight gained from this computational study challenges the current models used to explain biological vision systems and to construct robotic vision systems. Considering the statistical difficulties in image velocity estimation in conjunction with the problem of discontinuity detection in motion fields suggests that theoretically the process of optical flow computations should not be carried out in isolation but in conjunction with the higher level processes of 3D motion estimation, segmentation and shape computation. VL - 40 SN - 0042-6989 UR - http://www.sciencedirect.com/science/article/pii/S0042698999001625 CP - 1 M3 - 10.1016/S0042-6989(99)00162-5 ER - TY - CONF T1 - Polymorphic versus monomorphic points-to analysis T2 - Proceedings of the 7th International Static Analysis Symposium, Lecture Notes in Computer Science. Springer Verlag Y1 - 2000 A1 - Foster, Jeffrey S. A1 - Fahndrich,M. A1 - Aiken,A. JA - Proceedings of the 7th International Static Analysis Symposium, Lecture Notes in Computer Science. Springer Verlag ER - TY - CONF T1 - Receiver based management of low bandwidth access links T2 - IEEE INFOCOM 2000. Nineteenth Annual Joint Conference of the IEEE Computer and Communications Societies. Proceedings Y1 - 2000 A1 - Spring, Neil A1 - Chesire,M. A1 - Berryman,M. A1 - Sahasranaman,V. A1 - Anderson,T. A1 - Bershad,B. KW - Bandwidth KW - buffer storage KW - bulk-transfer applications KW - complex Web page KW - congestion control policy KW - Delay KW - dynamically loadable Linux kernel module KW - information resources KW - interactive network KW - Internet KW - Kernel KW - link utilization KW - Linux KW - low-bandwidth access links KW - mixed traffic load KW - packet latency KW - queue length KW - queueing theory KW - receive socket buffer sizes KW - receiver-based management KW - response time KW - short flow prioritizing KW - Size control KW - Sockets KW - subscriber loops KW - TCP flow control KW - telecommunication congestion control KW - telecommunication network management KW - Telecommunication traffic KW - Testing KW - Throughput KW - Transport protocols KW - Unix KW - Web pages AB - In this paper, we describe a receiver-based congestion control policy that leverages TCP flow control mechanisms to prioritize mixed traffic loads across access links. We manage queueing at the access link to: (1) improve the response time of interactive network applications; (2) reduce congestion-related packet losses; while (3) maintaining high throughput for bulk-transfer applications. Our policy controls queue length by manipulating receive socket buffer sizes. We have implemented this solution in a dynamically loadable Linux kernel module, and tested it over low-bandwidth links. Our approach yields a 7-fold improvement in packet latency over an unmodified system while maintaining 94% link utilization. In the common case, congestion-related packet losses at the access link can be eliminated. Finally, by prioritizing short flows, we show that our system reduces the time to download a complex Web page during a large background transfer by a factor of two JA - IEEE INFOCOM 2000. Nineteenth Annual Joint Conference of the IEEE Computer and Communications Societies. Proceedings PB - IEEE VL - 1 SN - 0-7803-5880-5 M3 - 10.1109/INFCOM.2000.832194 ER - TY - JOUR T1 - A Review of Current Routing Protocols for Ad Hoc JF - IEEE Personal Communications Y1 - 2000 A1 - Royer,E.M. A1 - Toh,C.K. A1 - Hicks, Michael W. A1 - Kakkar,P. A1 - Moore,J. T A1 - Hicks, Michael W. A1 - Moore,J. T A1 - Alexander,D. S A1 - Gunter,C. A A1 - Nettles,S. A1 - others VL - 29 ER - TY - CHAP T1 - Scalable Resource Control in Active Networks T2 - Active NetworksActive Networks Y1 - 2000 A1 - Anagnostakis,Kostas A1 - Hicks, Michael W. A1 - Ioannidis,Sotiris A1 - Keromytis,Angelos A1 - Smith,Jonathan ED - Yasuda,Hiroshi AB - The increased complexity of the service model relative to store-and-forward routers has made resource management one of the paramount concerns in active networking research and engineering. In this paper,we address two major challenges in scaling resource management-to-many-node active networks. The first is the use of market mechanisms and trading amongst nodes and programs with varying degrees of competition and cooperation to provide a scalable approach to managing active network resources. The second is the use of a trust-management architecture to ensure that the participants in the resource management marketplace have a policy-driven “rule of law” in which marketplace decisions can be made and relied upon. We have used lottery scheduling and the Keynote trust-management system for our implementation, for which we provide some initial performance indications. JA - Active NetworksActive Networks T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 1942 SN - 978-3-540-41179-6 UR - http://dx.doi.org/10.1007/3-540-40057-5_25 ER - TY - JOUR T1 - Secure quality of service handling: SQoSH JF - IEEE Communications Magazine Y1 - 2000 A1 - Alexander,D. S A1 - Arbaugh, William A. A1 - Keromytis,A. D A1 - Muir,S. A1 - Smith,J. M KW - Acceleration KW - Access control KW - active networks KW - ALIEN active loader KW - Clocks KW - Computer network management KW - cryptographic credentials KW - cryptography KW - customized networking services KW - Data security KW - Data structures KW - denial-of-service attacks KW - interfaces KW - Kernel KW - loaded modules KW - network resources KW - network traffic KW - open signaling KW - packet switching KW - Piglet lightweight device kernel KW - programmable network element KW - programmable network infrastructures KW - Programming profession KW - Proposals KW - quality of service KW - remote invocation KW - resource control KW - restricted control of quality of service KW - SANE KW - scheduling KW - scheduling discipline KW - secure active network environment architecture KW - secure quality of service handling KW - security infrastructure KW - security risks KW - SQoSH KW - SwitchWare architecture KW - telecommunication security KW - tuning knobs KW - virtual clock AB - Proposals for programmable network infrastructures, such as active networks and open signaling, provide programmers with access to network resources and data structures. The motivation for providing these interfaces is accelerated introduction of new services, but exposure of the interfaces introduces many new security risks. We describe some of the security issues raised by active networks. We then describe our secure active network environment (SANE) architecture. SANE was designed as a security infrastructure for active networks, and was implemented in the SwitchWare architecture. SANE restricts the actions that loaded modules can perform by restricting the resources that can be named; this is further extended to remote invocation by means of cryptographic credentials. SANE can be extended to support restricted control of quality of service in a programmable network element. The Piglet lightweight device kernel provides a “virtual clock” type of scheduling discipline for network traffic, and exports several tuning knobs with which the clock can be adjusted. The ALIEN active loader provides safe access to these knobs to modules that operate on the network element. Thus, the proposed SQoSH architecture is able to provide safe, secure access to network resources, while allowing these resources to be managed by end users needing customized networking services. A desirable consequence of SQoSH's integration of access control and resource control is that a large class of denial-of-service attacks, unaddressed solely with access control and cryptographic protocols, can now be prevented VL - 38 SN - 0163-6804 CP - 4 M3 - 10.1109/35.833566 ER - TY - CONF T1 - The statistics of optical flow: implications for the process of correspondence in vision T2 - 15th International Conference on Pattern Recognition, 2000. Proceedings Y1 - 2000 A1 - Fermüller, Cornelia A1 - Aloimonos, J. KW - Bias KW - Computer vision KW - correlation KW - correlation methods KW - energy-based method KW - flow estimation KW - Frequency estimation KW - gradient method KW - gradient methods KW - Image analysis KW - Image motion analysis KW - Image sequences KW - least squares KW - least squares approximations KW - Motion estimation KW - Nonlinear optics KW - Optical feedback KW - optical flow KW - Optical harmonic generation KW - Optical noise KW - Statistics KW - Visual perception AB - This paper studies the three major categories of flow estimation methods: gradient-based, energy-based, and correlation methods; it analyzes different ways of compounding 1D motion estimates (image gradients, spatio-temporal frequency triplets, local correlation estimates) into 2D velocity estimates, including linear and nonlinear methods. Correcting for the bias would require knowledge of the noise parameters. In many situations, however, these are difficult to estimate accurately, as they change with the dynamic imagery in unpredictable and complex ways. Thus, the bias really is a problem inherent to optical flow estimation. We argue that the bias is also integral to the human visual system. It is the cause of the illusory perception of motion in the Ouchi pattern and also explains various psychophysical studies of the perception of moving plaids. Finally, the implication of the analysis is that flow or correspondence can be estimated very accurately only when feedback is utilized JA - 15th International Conference on Pattern Recognition, 2000. Proceedings PB - IEEE VL - 1 SN - 0-7695-0750-6 M3 - 10.1109/ICPR.2000.905288 ER - TY - JOUR T1 - Structure from motion: Beyond the epipolar constraint JF - International Journal of Computer Vision Y1 - 2000 A1 - Brodskỳ, T. A1 - Fermüller, Cornelia A1 - Aloimonos, J. VL - 37 CP - 3 ER - TY - MGZN T1 - Windows of Vulnerability: A Case Study Analysis Y1 - 2000 A1 - Arbaugh, William A. A1 - Fithen,William L. A1 - McHugh,John AB - The authors propose a life-cycle model for system vulnerabilities, applying to three case studies to show how systems remain vulnerable long after security fixes are available. Complex information and communication systems give rise to design, implementation, and management errors, leading to a vulnerability in an information technology product that can allow security policy violations. Using their vulnerability life-cycle model, the authors present a case study analysis of specific computer vulnerabilities. For each case, the authors provide background information about the vulnerability, such as how attackers exploited it and which systems were affected. They tie the case to the life-cycle model by identifying the dates for each state within the model. Finally, they use a histogram of reported intrusions to show the life of the vulnerability and conclude with an analysis specific to the particular vulnerability. JA - Computer VL - 33 SN - 0018-9162 CP - 12 ER - TY - CHAP T1 - Active Perception T2 - Wiley Encyclopedia of Electrical and Electronics EngineeringWiley Encyclopedia of Electrical and Electronics Engineering Y1 - 1999 A1 - Fermüller, Cornelia A1 - Aloimonos, J. JA - Wiley Encyclopedia of Electrical and Electronics EngineeringWiley Encyclopedia of Electrical and Electronics Engineering PB - John Wiley & Sons, Inc. SN - 9780471346081 UR - http://onlinelibrary.wiley.com/doi/10.1002/047134608X.W5515/abstract?systemMessage=Wiley+Online+Library+will+be+disrupted+17+March+from+10-14+GMT+%2806-10+EDT%29+for+essential+maintenance&userIsAuthenticated=false&deniedAccessCustomisedMessage= ER - TY - CONF T1 - Advances in spherical harmonic device modeling: calibration and nanoscale electron dynamics T2 - Simulation of Semiconductor Processes and Devices, 1999. SISPAD '99. 1999 International Conference on Y1 - 1999 A1 - Lin,Chung-Kai A1 - Goldsman,N. A1 - Mayergoyz, Issak D A1 - Aronowitz,S. A1 - Belova,N. KW - Boltzmann KW - characteristics;SHBTE KW - current;surface KW - device KW - dynamics;spherical KW - electron KW - equation;calibration;semiconductor KW - equation;I-V KW - harmonic KW - model;substrate KW - models;surface KW - scattering; KW - scattering;Boltzmann KW - simulation;calibration;nanoscale KW - transport AB - Improvements in the Spherical Harmonic (SH) method for solving Boltzmann Transport Equation (BTE) are presented. The simulation results provide the same physical detail as analytical band Monte Carlo (MC) calculations, and are obtained approximately a thousand times faster. A new physical model for surface scattering has also been developed. As a result, the SHBTE model achieves calibration for a complete process of I-V characteristics and substrate current consistently for the first time JA - Simulation of Semiconductor Processes and Devices, 1999. SISPAD '99. 1999 International Conference on M3 - 10.1109/SISPAD.1999.799287 ER - TY - CONF T1 - Automated punch shape synthesis for sheet metal bending operations Y1 - 1999 A1 - Alva,U. A1 - Gupta,S.K. ER - TY - JOUR T1 - Binary version management for computational grids JF - Parallel processing letters Y1 - 1999 A1 - Hollingsworth, Jeffrey K A1 - Miller, E. L A1 - Akala, K. VL - 9 CP - 2 ER - TY - JOUR T1 - Coverage estimation methods for stratified fault-injection JF - Computers, IEEE Transactions on Y1 - 1999 A1 - Michel Cukier A1 - Powell,D. A1 - Ariat,J. KW - Bayes methods KW - Bayesian estimations KW - confidence regions KW - coverage estimation methods KW - fault tolerance coverage KW - fault tolerant computing KW - frequentist confidence limits KW - parameter estimation KW - parameters estimation KW - Pearson distribution system KW - statistical processing KW - stratified fault-injection KW - stratified sampling KW - vectorial statistic AB - This paper addresses the problem of estimating fault tolerance coverage through statistical processing of observations collected in fault-injection experiments. In an earlier paper, venous estimators based on simple sampling in the complete fault/activity input space and stratified sampling in a partitioned space were studied; frequentist confidence limits were derived based on a normal approximation. In this paper, the validity of this approximation is analyzed. The theory of confidence regions is introduced to estimate coverage without approximation when stratification is used. Three statistics are considered for defining confidence regions. It is shown that one-a vectorial statistic-is often more conservative than the other two. However, only the vectorial statistic is computationally tractable. We then consider Bayesian estimation methods for stratified sampling. Two methods are presented to obtain an approximation of the posterior distribution of the coverage by calculating its moments. The moments are then used to identify the type of the distribution in the Pearson distribution system, to estimate its parameters, and to obtain the coverage confidence limit. Three hypothetical example systems are used to compare the validity and the conservatism of the frequentist and Bayesian estimations VL - 48 SN - 0018-9340 CP - 7 M3 - 10.1109/12.780878 ER - TY - CONF T1 - Field-to-frame transcoding with spatial and temporal downsampling T2 - Image Processing, 1999. ICIP 99. Proceedings. 1999 International Conference on Y1 - 1999 A1 - Wee,S.J. A1 - Apostolopoulos,J.G. A1 - Feamster, Nick KW - data compression KW - decoding KW - Encoding KW - field-coded interlaced video KW - field-to-frame transcoding KW - frame-coded progressive video KW - H.263 motion estimation KW - H.263 transcoding KW - high-rate compressed bitstreams KW - lower-rate compressed bitstreams KW - Motion estimation KW - MPEG-1 KW - MPEG-2 KW - MPEG-4 KW - spatial downsampling KW - standards KW - temporal downsampling KW - transcoder KW - video coding KW - video compression standards AB - We present an algorithm for transcoding high-rate compressed bitstreams containing field-coded interlaced video to lower-rate compressed bitstreams containing frame-coded progressive video. We focus on MPEG-2 to H.263 transcoding, however these results can be extended to other lower-rate video compression standards including MPEG-4 simple profile and MPEG-1. A conventional approach to the transcoding problem involves decoding the input bitstream, spatially and temporally downsampling the decoded frames, and re-encoding the result. The proposed transcoder achieves improved performance by exploiting the details of the MPEG-2 and H.263 compression standards when performing interlaced to progressive (or field to frame) conversion with spatial downsampling and frame-rate reduction. The transcoder reduces the MPEG-2 decoding requirements by temporally downsampling the data at the bitstream level and reduces the H.263 encoding requirements by largely bypassing H.263 motion estimation by reusing the motion vectors and coding modes given in the input bitstream. In software implementations, the proposed approach achieved a 5 times; speedup over the conventional approach with only a 0.3 and 0.5 dB loss in PSNR for the Carousel and Bus sequences JA - Image Processing, 1999. ICIP 99. Proceedings. 1999 International Conference on VL - 4 M3 - 10.1109/ICIP.1999.819593 ER - TY - CONF T1 - Fkpurang, darsana, traum, cfa, perlisg@ cs. umd. edu T2 - In Proceedings of the IJCAI’99 Workshop on Practical Reasoning and Rationality Y1 - 1999 A1 - Edu,C. U A1 - Purang,K. A1 - Purushothaman,D. A1 - Traum,D. A1 - Andersen,C. A1 - Perlis, Don JA - In Proceedings of the IJCAI’99 Workshop on Practical Reasoning and Rationality ER - TY - CONF T1 - Independent motion: the importance of history T2 - Computer Vision and Pattern Recognition, 1999. IEEE Computer Society Conference on. Y1 - 1999 A1 - Pless, R. A1 - Brodsky, T. A1 - Aloimonos, J. KW - aerial visual surveillance KW - background image KW - Fluid flow measurement KW - Frequency measurement KW - History KW - Motion detection KW - Motion estimation KW - Motion measurement KW - Noise measurement KW - Optical computing KW - Optical noise KW - spatiotemporal image intensity gradient measurements KW - Spatiotemporal phenomena KW - Surveillance KW - Video sequences AB - We consider a problem central in aerial visual surveillance applications-detection and tracking of small, independently moving objects in long and noisy video sequences. We directly use spatiotemporal image intensity gradient measurements to compute an exact model of background motion. This allows the creation of accurate mosaics over many frames and the definition of a constraint violation function which acts as an indication of independent motion. A novel temporal integration method maintains confidence measures over long subsequences without computing the optic flow, requiring object models, or using a Kalman filler. The mosaic acts as a stable feature frame, allowing precise localization of the independently moving objects. We present a statistical analysis of the effects of image noise on the constraint violation measure and find a good match between the predicted probability distribution function and the measured sample frequencies in a test sequence JA - Computer Vision and Pattern Recognition, 1999. IEEE Computer Society Conference on. PB - IEEE VL - 2 SN - 0-7695-0149-4 M3 - 10.1109/CVPR.1999.784614 ER - TY - CONF T1 - Mixed initiative dialogue and intelligence via active logic T2 - proceedings of the AAAI99 Workshop on Mixed-Initiative Intelligence Y1 - 1999 A1 - Andersen,C. A1 - Traum,D. A1 - Purang,K. A1 - Purushothaman,D. A1 - Perlis, Don JA - proceedings of the AAAI99 Workshop on Mixed-Initiative Intelligence ER - TY - CONF T1 - Motion Segmentation: A Synergistic Approach T2 - Computer Vision and Pattern Recognition, IEEE Computer Society Conference on Y1 - 1999 A1 - Fermüller, Cornelia A1 - Brodsky, Tomas A1 - Aloimonos, J. KW - epipolar minimization KW - independent motion detection KW - Motion analysis AB - Since estimation of camera motion requires knowledge of independent motion, and moving object detection and localization requires knowledge about the camera motion, the two problems of motion estimation and segmentation need to be solved together in a synergistic manner. This paper provides an approach to treating both these problems simultaneously. The technique introduced here is based on a novel concept, ``scene ruggedness,'' which parameterizes the variation in estimated scene depth with the error in the underlying three-dimensional (3D) motion. The idea is that incorrect 3D motion estimates cause distortions in the estimated depth map, and as a result smooth scene patches are computed as rugged surfaces. The correct 3D motion can be distinguished, as it does not cause any distortion and thus gives rise to the background patches with the least depth variation between depth discontinuities, with the locations corresponding to independent motion being rugged. The algorithm presented employs a binocular observer whose nature is exploited in the extraction of depth discontinuities, a step that facilitates the overall procedure, but the technique can be extended to a monocular observer in a variety of ways. JA - Computer Vision and Pattern Recognition, IEEE Computer Society Conference on PB - IEEE Computer Society CY - Los Alamitos, CA, USA VL - 2 M3 - http://doi.ieeecomputersociety.org/10.1109/CVPR.1999.784633 ER - TY - CONF T1 - PLANet: an active internetwork T2 - IEEE INFOCOM '99. Eighteenth Annual Joint Conference of the IEEE Computer and Communications Societies. Proceedings Y1 - 1999 A1 - Hicks, Michael W. A1 - Moore,J. T A1 - Alexander,D. S A1 - Gunter,C. A A1 - Nettles,S. M KW - 100 Mbit/s KW - 300 MHz KW - 48 Mbit/s KW - active internetwork KW - active network architecture KW - active network implementation KW - byte-code-interpreted applications KW - Computer architecture KW - Computer languages KW - Computer networks KW - congested conditions KW - dynamic programming KW - dynamic router extensions KW - Ethernet KW - Ethernet networks KW - INFORMATION SCIENCE KW - Internet KW - Internet-like services KW - internetworking KW - IP KW - IP networks KW - link layers KW - Linux user-space applications KW - Local area networks KW - ML dialect KW - Network performance KW - networking operations KW - OCaml KW - Packet Language for Active Networks KW - packet programs KW - packet switching KW - Pentium-II KW - performance KW - performance evaluation KW - PLAN KW - PLANet KW - Planets KW - programmability features KW - programming languages KW - router functionality KW - special purpose programming language KW - Switches KW - telecommunication network routing KW - Transport protocols KW - Web and internet services AB - We present PLANet: an active network architecture and implementation. In addition to a standard suite of Internet-like services, PLANet has two key programmability features: (1) all packets contain programs; and (2) router functionality may be extended dynamically. Packet programs are written in our special purpose programming language PLAN, the Packet Language for Active Networks, while dynamic router extensions are written in OCaml, a dialect of ML. Currently, PLANet routers run as byte-code-interpreted Linux user-space applications, and support Ethernet and IP as link layers. PLANet achieves respectable performance on standard networking operations: on 300 MHz Pentium-II's attached to 100 Mbps Ethernet, PLANet can route 48 Mbps and switch over 5000 packets per second. We demonstrate the utility of PLANet's activeness by showing experimentally how it can nontrivially improve application and aggregate network performance in congested conditions JA - IEEE INFOCOM '99. Eighteenth Annual Joint Conference of the IEEE Computer and Communications Societies. Proceedings PB - IEEE VL - 3 SN - 0-7803-5417-6 M3 - 10.1109/INFCOM.1999.751668 ER - TY - CONF T1 - Practical reasoning and plan execution with active logic T2 - Proceedings of the IJCAI-99 Workshop on Practical Reasoning and Rationality Y1 - 1999 A1 - Purang,K. A1 - Purushothaman,D. A1 - Traum,D. A1 - Andersen,C. A1 - Perlis, Don JA - Proceedings of the IJCAI-99 Workshop on Practical Reasoning and Rationality ER - TY - JOUR T1 - Reports on the AAAI Fall Symposia JF - AI Magazine Y1 - 1999 A1 - De Giacomo,Giuseppe A1 - desJardins, Marie A1 - Canamero,Dolores A1 - Wasson,Glenn A1 - Littman,Michael A1 - Allwein,Gerard A1 - Marriott,Kim A1 - Meyer,Bernd A1 - Webb,Barbara A1 - Consi,Tom AB - The Association for the Advancement of Artificial Intelligence (AAAI) held its 1998 Fall Symposium Series on 23 to 25 October at the Omni Rosen Hotel in Orlando, Florida. This article contains summaries of seven of the symposia that were conducted: (1) Cognitive Robotics; (2) Distributed, Continual Planning; (3) Emotional and Intelligent: The Tangled Knot of Cognition; (4) Integrated Planning for Autonomous Agent Architectures; (5) Planning with Partially Observable Markov Decision Processes; (6) Reasoning with Visual and Diagrammatic Representations; and (7) Robotics and Biology: Developing Connections. VL - 20 SN - 0738-4602 UR - http://www.aaai.org/ojs/index.php/aimagazine/article/viewArticle/1470 CP - 3 M3 - 10.1609/aimag.v20i3.1470 ER - TY - BOOK T1 - The RNA World Y1 - 1999 A1 - Woodson,Sarah A. A1 - Mount, Stephen M. ED - Gesteland,Raymond F. ED - Cech,Thomas R. ED - Atkins,John F. PB - Cold Spring Harbor Laboratory Press CY - Cold Spring Harbor, New York ER - TY - JOUR T1 - The Role of Children in the Design of New Technology JF - Saatavilla www-muodossa: ftp://ftp. cs. umd. edu/pub/hcil/Reports-Abstracts-Bibliography/99-23html/99-23. pdf (Luettu 17.1. 2007) Y1 - 1999 A1 - Allison,D. ER - TY - CONF T1 - Shape from Video T2 - Computer Vision and Pattern Recognition, IEEE Computer Society Conference on Y1 - 1999 A1 - Brodsky, Tomas A1 - Fermüller, Cornelia A1 - Aloimonos, J. KW - epipolar minimization KW - model extraction KW - Motion analysis KW - vision and graphics AB - This paper presents a novel technique for recovering the shape of a static scene from a video sequence due to a rigidly moving camera. The solution procedure consists of two stages. In the first stage, the rigid motion of the camera at each instant in time is recovered. This provides the transformation between successive viewing positions. The solution is achieved through new constraints which relate 3D motion and shape directly to the image derivatives. These constraints allow the combination of the processes of 3D motion estimation and segmentation by exploiting the geometry and statistics inherent in the data. In the second stage the scene surfaces are reconstructed through an optimization procedure which utilizes data from all the frames of a short video sequence. A number of experimental results demonstrate the potential of the approach. JA - Computer Vision and Pattern Recognition, IEEE Computer Society Conference on PB - IEEE Computer Society CY - Los Alamitos, CA, USA VL - 2 M3 - http://doi.ieeecomputersociety.org/10.1109/CVPR.1999.784622 ER - TY - CONF T1 - Skip Strips: maintaining triangle strips for view-dependent rendering T2 - Visualization '99. Proceedings Y1 - 1999 A1 - El-Sana,J. A1 - Azanli,E. A1 - Varshney, Amitabh KW - (computer KW - Acceleration KW - acceleration;graphics KW - applications;path KW - applications;skip-list-like KW - changes;view-dependent KW - compression;rendering KW - connectivity;triangle KW - data KW - datasets;graphics KW - datasets;static KW - environments;data KW - equipment;data KW - graphic KW - Graphics KW - graphics);spatial KW - hardware;hardware-supported KW - hierarchy KW - manner;static KW - mechanism;immediate-mode KW - mesh KW - meshes;triangle KW - nodes;view-dependent KW - rendering;view-dependent KW - simplification;visualization;computer KW - Skip KW - Strips;complex KW - strips;vertex KW - structure;dynamic KW - structures; KW - techniques;retained-mode KW - triangle KW - visualisation;rendering AB - View-dependent simplification has emerged as a powerful tool for graphics acceleration in visualization of complex environments. However, view-dependent simplification techniques have not been able to take full advantage of the underlying graphics hardware. Specifically, triangle strips are a widely used hardware-supported mechanism to compactly represent and efficiently render static triangle meshes. However, in a view-dependent framework, the triangle mesh connectivity changes at every frame, making it difficult to use triangle strips. We present a novel data structure, Skip Strip, that efficiently maintains triangle strips during such view-dependent changes. A Skip Strip stores the vertex hierarchy nodes in a skip-list-like manner with path compression. We anticipate that Skip Strips will provide a road map to combine rendering acceleration techniques for static datasets, typical of retained-mode graphics applications, with those for dynamic datasets found in immediate-mode applications. JA - Visualization '99. Proceedings M3 - 10.1109/VISUAL.1999.809877 ER - TY - CONF T1 - Statistical biases in optic flow T2 - Computer Vision and Pattern Recognition, 1999. IEEE Computer Society Conference on. Y1 - 1999 A1 - Fermüller, Cornelia A1 - Pless, R. A1 - Aloimonos, J. KW - Distributed computing KW - Frequency domain analysis KW - HUMANS KW - image derivatives KW - Image motion analysis KW - Image sequences KW - Least squares methods KW - Motion estimation KW - Optical computing KW - Optical distortion KW - optical flow KW - Optical noise KW - Ouchi illusion KW - perception of motion KW - Psychology KW - Spatiotemporal phenomena KW - statistical analysis KW - systematic bias KW - total least squares AB - The computation of optical flow from image derivatives is biased in regions of non uniform gradient distributions. A least-squares or total least squares approach to computing optic flow from image derivatives even in regions of consistent flow can lead to a systematic bias dependent upon the direction of the optic flow, the distribution of the gradient directions, and the distribution of the image noise. The bias a consistent underestimation of length and a directional error. Similar results hold for various methods of computing optical flow in the spatiotemporal frequency domain. The predicted bias in the optical flow is consistent with psychophysical evidence of human judgment of the velocity of moving plaids, and provides an explanation of the Ouchi illusion. Correction of the bias requires accurate estimates of the noise distribution; the failure of the human visual system to make these corrections illustrates both the difficulty of the task and the feasibility of using this distorted optic flow or undistorted normal flow in tasks requiring higher lever processing JA - Computer Vision and Pattern Recognition, 1999. IEEE Computer Society Conference on. PB - IEEE VL - 1 SN - 0-7695-0149-4 M3 - 10.1109/CVPR.1999.786994 ER - TY - JOUR T1 - Temporal visualization for legal case histories JF - PROCEEDINGS OF THE ANNUAL MEETING-AMERICAN SOCIETY FOR INFORMATION SCIENCE Y1 - 1999 A1 - Harris,C. A1 - Allen,R.B. A1 - Plaisant, Catherine A1 - Shneiderman, Ben AB - This paper discusses visualization of legal information using a tool for temporal information called LifeLines. The direct and indirect histories of cases can become very complex. We explored ways that LifeLines could aid in viewing the links between the original case and the direct and indirect histories. The Apple Computer, Inc. v. Microsoft Corporation and Hewlett Packard Company case is used to illustrate the prototype. For example, if users want to find out how the rulings or statutes changed throughout this case, they could retrieve this information within a single display. Using the timeline, users could also choose at which point in time they would like to begin viewing the case. LifeLines support various views of a case's history. For instance, users can view the trial history of a case, the references involved in a case, and citations made to a case. The paper describes improvements to LifeLines that could help in providing a more useful visualization of case history. VL - 36 ER - TY - CONF T1 - A theory of type qualifiers T2 - ACM SIGPLAN Notices Y1 - 1999 A1 - Foster, Jeffrey S. A1 - Fähndrich,M. A1 - Aiken,A. JA - ACM SIGPLAN Notices VL - 34 ER - TY - JOUR T1 - 3D motion and shape representations in visual servo control JF - The International Journal of Robotics Research Y1 - 1998 A1 - Fermüller, Cornelia A1 - Cheong, L. F A1 - Aloimonos, J. VL - 17 CP - 1 ER - TY - JOUR T1 - Ambiguity in Structure from Motion: Sphere versus Plane JF - International Journal of Computer Vision Y1 - 1998 A1 - Fermüller, Cornelia A1 - Aloimonos, J. AB - If 3D rigid motion can be correctly estimated from image sequences, the structure of the scene can be correctly derived using the equations for image formation. However, an error in the estimation of 3D motion will result in the computation of a distorted version of the scene structure. Of computational interest are these regions in space where the distortions are such that the depths become negative, because in order for the scene to be visible it has to lie in front of the image, and thus the corresponding depth estimates have to be positive. The stability analysis for the structure from motion problem presented in this paper investigates the optimal relationship between the errors in the estimated translational and rotational parameters of a rigid motion that results in the estimation of a minimum number of negative depth values. The input used is the value of the flow along some direction, which is more general than optic flow or correspondence. For a planar retina it is shown that the optimal configuration is achieved when the projections of the translational and rotational errors on the image plane are perpendicular. Furthermore, the projection of the actual and the estimated translation lie on a line through the center. For a spherical retina, given a rotational error, the optimal translation is the correct one; given a translational error, the optimal rotational negative deptherror depends both in direction and value on the actual and estimated translation as well as the scene in view. The proofs, besides illuminating the confounding of translation and rotation in structure from motion, have an important application to ecological optics. The same analysis provides a computational explanation of why it is easier to estimate self-motion in the case of a spherical retina and why shape can be estimated easily in the case of a planar retina, thus suggesting that nature's design of compound eyes (or panoramic vision) for flying systems and camera-type eyes for primates (and other systems that perform manipulation) is optimal. VL - 28 SN - 0920-5691 UR - http://dx.doi.org/10.1023/A:1008063000586 CP - 2 ER - TY - CONF T1 - Approximation algorithms for multiple-tool miling T2 - Proceedings of the fourteenth annual symposium on Computational geometry Y1 - 1998 A1 - Arya,Sunil A1 - Cheng,Siu-Wing A1 - Mount, Dave JA - Proceedings of the fourteenth annual symposium on Computational geometry T3 - SCG '98 PB - ACM CY - New York, NY, USA SN - 0-89791-973-4 UR - http://doi.acm.org/10.1145/276884.276918 M3 - 10.1145/276884.276918 ER - TY - CONF T1 - Automated recovery in a secure bootstrap process T2 - Proceedings of the Symposium on Network and Distributed Systems Security (NDSS’98) Y1 - 1998 A1 - Arbaugh, William A. A1 - Keromytis,A. D A1 - Farber,D. J A1 - Smith,J. M JA - Proceedings of the Symposium on Network and Distributed Systems Security (NDSS’98) ER - TY - CONF T1 - Benchmarking a network of PCs running parallel applications T2 - Performance, Computing and Communications, 1998. IPCCC '98., IEEE International Y1 - 1998 A1 - Hollingsworth, Jeffrey K A1 - Guven, E. A1 - Akinlar, C. KW - 100 Mbit/s KW - 125 mus KW - Aerodynamics KW - Application software KW - communication micro-benchmarks KW - default mathematical libraries KW - Delay KW - Ethernet KW - Ethernet networks KW - gcc KW - latency KW - lightweight message-passing protocol KW - Linux KW - Local area networks KW - mathematics computing KW - Message passing KW - microcomputer applications KW - Microsoft Windows NT KW - NAS parallel benchmarks KW - network operating systems KW - Numerical simulation KW - parallel applications KW - PARALLEL PROCESSING KW - PC network benchmarking KW - performance comparison KW - performance evaluation KW - Personal communication networks KW - Protocols KW - PVM KW - running time KW - software libraries KW - System software KW - system software configurations KW - TCP/IP KW - TCPIP KW - Transport protocols KW - U-Net active messages KW - Visual C++ AB - Presents a benchmarking study that compares the performance of a network of four PCs connected by a 100 Mbit/s fast Ethernet running three different system software configurations: TCP/IP on Windows NT, TCP/IP on Linux and a lightweight message-passing protocol (U-Net active messages) on Linux. For each configuration, we report results for communication micro-benchmarks and the NAS (Numerical Aerodynamics Simulation) parallel benchmarks. For the NAS benchmarks, the overall running time using Linux TCP/IP was 12-500% less than the Windows NT TCP/IP configuration. Likewise, the Linux U-Net based message-passing protocol outperformed the Linux TCP/IP version by 5-200%+. We also show that, by using Linux U-Net, we are able to achieve 125 μs latency between two processes using PVM. Finally, we report that the default mathematical libraries supplied with NT (for both gcc and Visual C++) are substantially slower than the one supplied with Linux JA - Performance, Computing and Communications, 1998. IPCCC '98., IEEE International PB - IEEE SN - 0-7803-4468-5 M3 - 10.1109/PCCC.1998.659876 ER - TY - CHAP T1 - Beyond the Epipolar Constraint: Integrating 3D Motion and Structure Estimation T2 - 3D Structure from Multiple Images of Large-Scale Environments3D Structure from Multiple Images of Large-Scale Environments Y1 - 1998 A1 - Brodský,Tomáš A1 - Fermüller, Cornelia A1 - Aloimonos, J. ED - Koch,Reinhard ED - Van Gool,Luc AB - This paper develops a novel solution to the problem of recovering the structure of a scene given an uncalibrated video sequence depicting the scene. The essence of the technique lies in a method for recovering the rigid transformation between the different views in the image sequence. Knowledge of this 3D motion allows for self-calibration and for subsequent recovery of 3D structure. The introduced method breaks away from applying only the traditionally used epipolar constraint and introduces a new constraint based on the interaction between 3D motion and shape. Up to now, structure from motion algorithms proceeded in two well defined steps, where the first and most important step is recovering the rigid transformation between two views, and the subsequent step is using this transformation to compute the structure of the scene in view. Here both aforementioned steps are accomplished in a synergistic manner. Existing approaches to 3D motion estimation are mostly based on the use of optic flow which however poses a problem at the locations of depth discontinuities. If we knew where depth discontinuities were, we could (using a multitude of approaches based on smoothness constraints) estimate accurately flow values for image patches corresponding to smooth scene patches; but to know the discontinuities requires solving the structure from motion problem first. In the past this dilemma has been addressed by improving the estimation of flow through sophisticated optimization techniques, whose performance often depends on the scene in view. In this paper the main idea is based on the interaction between 3D motion and shape which allows us to estimate the 3D motion while at the same time segmenting the scene. If we use a wrong 3D motion estimate to compute depth, then we obtain a distorted version of the depth function. The distortion, however, is such that the worse the motion estimate, the more likely we are to obtain depth estimates that are locally unsmooth, i.e., they vary more than the correct ones. Since local variability of depth is due either to the existence of a discontinuity or to a wrong 3D motion estimate, being able to differentiate between these two cases provides the correct motion, which yields the “smoothest” estimated depth as well as the image locations of scene discontinuities. Although no optic flow values are computed, we show that our algorithm is very much related to minimizing the epipolar constraint when the scene in view is smooth. When however the imaged scene is not smooth, the introduced constraint has in general different properties from the epipolar constraint and we present experimental results with real sequences where it performs better. JA - 3D Structure from Multiple Images of Large-Scale Environments3D Structure from Multiple Images of Large-Scale Environments T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 1506 SN - 978-3-540-65310-3 UR - http://dx.doi.org/10.1007/3-540-49437-5_8 ER - TY - JOUR T1 - The design and evaluation of a high-performance earth science database JF - Parallel Computing Y1 - 1998 A1 - Shock,Carter T. A1 - Chang,Chialin A1 - Moon,Bongki A1 - Acharya,Anurag A1 - Davis, Larry S. A1 - Saltz,Joel A1 - Sussman, Alan KW - Communication KW - High-performance I/O KW - load balancing KW - scalability KW - Scientific databases AB - Earth scientists have encountered two major obstacles in their attempts to use remotely sensed imagery to analyze the earth's land cover dynamics. First, the volume of data involved is very large and second, significant preprocessing is needed before the data can be used. This is particularly so for studies that analyze global trends using data sets that cover multiple years. In this paper, we present the design of an earth science database as well as our early experiences with it. The primary design goal of this database is to facilitate efficient access to and preprocessing of large volumes of satellite data. Our initial design assumed that the main bottleneck in the system would be retrieving data from the disks. However, experimental results show that precise identification of all the data values corresponding to a query can take a significant amount of time. The problem is even more pronounced in designing the system to attempt to minimize time spent performing I/O. We therefore discuss a major redesign of the system that includes a reworking of the indexing scheme and a reorganization of the data on disks. Experimental results show that the redesigned system performs significantly better than the original system, providing interactive response times for local queries. VL - 24 SN - 0167-8191 UR - http://www.sciencedirect.com/science/article/pii/S0167819197001178 CP - 1 M3 - 10.1016/S0167-8191(97)00117-8 ER - TY - JOUR T1 - DHCP++: Applying an efficient implementation method for fail-stop cryptographic protocols JF - Proceedings of Global Internet (GlobeCom)’98 Y1 - 1998 A1 - Arbaugh, William A. A1 - Keromytis,A. D A1 - Smith,J. M ER - TY - CONF T1 - Digital dynamic telepathology–the Virtual Microscope. T2 - Proceedings of the AMIA Symposium Y1 - 1998 A1 - Afework,A. A1 - Beynon,M. D A1 - Bustamante,F. A1 - Cho,S. A1 - Demarzo,A. A1 - Ferreira,R. A1 - Miller,R. A1 - Silberman,M. A1 - Saltz, J. A1 - Sussman, Alan A1 - others JA - Proceedings of the AMIA Symposium ER - TY - JOUR T1 - Directions of Motion Fields are Hardly Ever Ambiguous JF - International Journal of Computer Vision Y1 - 1998 A1 - Brodsky, Tomas A1 - Fermüller, Cornelia A1 - Aloimonos, J. AB - If instead of the full motion field, we consider only the direction of the motion field due to a rigid motion, what can we say about the three-dimensional motion information contained in it? This paper provides a geometric analysis of this question based solely on the constraint that the depth of the surfaces in view is positive. The motivation behind this analysis is to provide a theoretical foundation for image constraints employing only the sign of flow in various directions and justify their utilization for addressing 3D dynamic vision problems. VL - 26 SN - 0920-5691 UR - http://dx.doi.org/10.1023/A:1007928406666 CP - 1 ER - TY - CHAP T1 - Drawing of Two-Dimensional Irregular Meshes T2 - Graph DrawingGraph Drawing Y1 - 1998 A1 - Aggarwal,Alok A1 - Rao Kosaraju,S. A1 - Pop, Mihai ED - Whitesides,Sue AB - We present a method for transforming two-dimensional irregular meshes into square meshes with only a constant blow up in area. We also explore context invariant transformations of irregular meshes into square meshes and provide a lower bound for the transformation of down-staircases. JA - Graph DrawingGraph Drawing T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 1547 SN - 978-3-540-65473-5 UR - http://dx.doi.org/10.1007/3-540-37623-2_1 ER - TY - JOUR T1 - Effects of Errors in the Viewing Geometry on Shape Estimation JF - Computer Vision and Image Understanding Y1 - 1998 A1 - LoongFah Cheong A1 - Fermüller, Cornelia A1 - Aloimonos, J. AB - A sequence of images acquired by a moving sensor contains information about the three-dimensional motion of the sensor and the shape of the imaged scene. Interesting research during the past few years has attempted to characterize the errors that arise in computing 3D motion (egomotion estimation) as well as the errors that result in the estimation of the scene's structure (structure from motion). Previous research is characterized by the use of optic flow or correspondence of features in the analysis as well as by the employment of particular algorithms and models of the scene in recovering expressions for the resulting errors. This paper presents a geometric framework that characterizes the relationship between 3D motion and shape in the presence of errors. We examine how the three-dimensional space recovered by a moving monocular observer, whose 3D motion is estimated with some error, is distorted. We characterize the space of distortions by its level sets, that is, we characterize the systematic distortion via a family of iso-distortion surfaces, which describes the locus over which the depths of points in the scene in view are distorted by the same multiplicative factor. The framework introduced in this way has a number of applications: Since the visible surfaces have positive depth (visibility constraint), by analyzing the geometry of the regions where the distortion factor is negative, that is, where the visibility constraint is violated, we make explicit situations which are likely to give rise to ambiguities in motion estimation, independent of the algorithm used. We provide a uniqueness analysis for 3D motion analysis from normal flow. We study the constraints on egomotion, object motion, and depth for an independently moving object to be detectable by a moving observer, and we offer a quantitative account of the precision needed in an inertial sensor for accurate estimation of 3D motion. VL - 71 SN - 1077-3142 UR - http://www.sciencedirect.com/science/article/pii/S1077314297906494 CP - 3 M3 - 10.1006/cviu.1997.0649 ER - TY - JOUR T1 - Effects of Errors in the Viewing Geometry on Shape Estimation* 1,* 2 JF - Computer Vision and Image Understanding Y1 - 1998 A1 - Cheong, L. F A1 - Fermüller, Cornelia A1 - Aloimonos, J. VL - 71 CP - 3 ER - TY - JOUR T1 - Emergent patterns of teaching/learning in electronic classrooms JF - Educational Technology Research and Development Y1 - 1998 A1 - Shneiderman, Ben A1 - Borkowski,Ellen A1 - Alavi,Maryam A1 - Norman,Kent AB - Novel patterns of teaching/learning have emerged from faculty and students who use our three teaching/learning theaters at the University of Maryland, College Park. These fully-equipped electronic classrooms have been used by 74 faculty in 264 semester-long courses since the fall of 1991 with largely enthusiastic reception by both faculty and students. The designers of the teaching/learning theaters sought to provide a technologically rich environment and a support staff so that faculty could concentrate on changing the traditional lecture from its unidirectional information flow to a more collaborative activity. As faculty have evolved their personal styles in using the electronic classrooms, novel patterns of teaching/learning have emerged. In addition to enhanced lectures, we identified three common patterns: (a) active individual learning, (b) small-group collaborative learning, and (c) entire-class collaborative learning. VL - 46 SN - 1042-1629 UR - http://dx.doi.org/10.1007/BF02299671 CP - 4 ER - TY - JOUR T1 - Extension of Spherical Harmonic Method to RF Transient Regime JF - Simulation of semiconductor processes and devices 1998: SISPAD 98 Y1 - 1998 A1 - Lin,C. K. A1 - Goldsman,N. A1 - Chang,C. H. A1 - Mayergoyz, Issak D A1 - Aronowitz,S. A1 - Dong,J. A1 - Belova,N. AB - The space and time dependent electron Boltzmann transport equation (BTE)is solved sclf-consistently with the Poisson and transient hole current-continuity equation. A transient Spherical Harmonic expansion method is used to solve the BTE. By this method we can efficiently solve the BTE in the RF regime to observe how the complete distribution function responds to a rapid transient. Calculations on a BJT, which give the time dependent distribution function over a large energy range 0-3eV, throughout the device, as well as average quantities, require only 40 minutes CPU time on an Alpha workstation. ER - TY - JOUR T1 - Frequentist and Bayesian Coverage Estimations for Stratified Fault-Injection JF - DEPENDABLE COMPUTING AND FAULT TOLERANT SYSTEMS Y1 - 1998 A1 - Michel Cukier A1 - Arlat,J. A1 - Powell,D. AB - This paper addresses the problem of estimating the coverage of fault tolerancethrough statistical processing of observations collected in fault-injection experiments. In an earlier paper, we have studied various frequentist estimation methods based on simple sampling in the whole fault/activity input space and stratified sampling in a partitioned space. In this paper, Bayesian estimation methods are introduced for stratified sampling. Two methods are presented to obtain an approximation of the posterior distribution of the coverage by calculating its moments. The moments are then used to identify the type of the distribution in the Pearson distribution system, to estimate its parameters and to obtain the coverage confidence limit. Two hypothetical example systems are used to compare the validity and the conservatism of the Bayesian and frequentist estimations. It is shown that one Bayesian estimation method is valid for both examples and that its estimations are much less conservative than the frequentist ones. However, the Bayesian estimations for stratified sampling are still conservative compared to estimations for simple sampling. VL - 11 UR - http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.29.6784&rep=rep1&type=pdf ER - TY - JOUR T1 - Genetic nomenclature for Trypanosoma and Leishmania. JF - Molecular and biochemical parasitology Y1 - 1998 A1 - Clayton,C. A1 - Adams,M. A1 - Almeida,R. A1 - Baltz,T. A1 - Barrett,M. A1 - Bastien,P. A1 - Belli,S. A1 - Beverley,S. A1 - Biteau,N. A1 - Blackwell,J. A1 - others VL - 97 CP - 1-2 ER - TY - JOUR T1 - Genetic nomenclature for Trypanosoma and Leishmania. JF - Mol Biochem Parasitol Y1 - 1998 A1 - Clayton, C A1 - Adams, M A1 - Almeida, R A1 - Baltz, T A1 - Barrett, M A1 - Bastien, P A1 - Belli, S A1 - Beverley, S A1 - Biteau, N A1 - Blackwell, J A1 - Blaineau, C A1 - Boshart, M A1 - Bringaud, F A1 - Cross, G A1 - Cruz, A A1 - Degrave, W A1 - Donelson, J A1 - El-Sayed, N A1 - Fu, G A1 - Ersfeld, K A1 - Gibson, W A1 - Gull, K A1 - Ivens, A A1 - Kelly, J A1 - Vanhamme, L KW - Animals KW - Leishmania KW - Terminology as Topic KW - Trypanosoma VL - 97 CP - 1-2 ER - TY - RPRT T1 - On the geometry of visual correspondence Y1 - 1998 A1 - Fermüller, Cornelia A1 - Aloimonos, J. AB - Image displacement fieldsoptical flow fields, stereo disparity fields, normal flow fieldsdue to rigid motion possess a global geometric structure which is independent of the scene in view. Motion vectors of certain lengths and directions are constraine d to lie on the imaging surface at particular loci whose location and form depends solely on the 3D motion parameters. If optical flow fields or stereo disparity fields are considered, then equal vectors are shown to lie on conic sections. Similarly, for normal motion fields, equal vectors lie within regions whose boundaries also constitute conics. By studying various properties of these curves and regions and their relationships, a characterization of the structure of rigid motion fields is given. The go al of this paper is to introduce a concept underlying the global structure of image displacement fields. This concept gives rise to various constraints that could form the basis of algorithms for the recovery of visual information from multiple views. JA - Technical Reports of the Computer Science Department ER - TY - RPRT T1 - An On-line Variable Length Binary Encoding Y1 - 1998 A1 - Acharya,Tinku A1 - JaJa, Joseph F. KW - Technical Report AB - We present a methodology of an on-line variable-length binaryencoding of a set of integers. The basic principle of this methodology is to maintain the prefix property amongst the codes assigned on-line to a set of integers growing dynamically. The prefix property enables unique decoding of a string of elements from this set. To show the utility of this on-line variable length binary encoding, we apply this methodology to encode the LZW codes. Application of this encoding scheme significantly improves the compression achieved by the standard LZW scheme. This encoding can be applied in other compression schemes to encode the pointers using variable-length binary codes. (Also cross-referenced as UMIACS-TR-95-39) PB - Instititue for Advanced Computer Studies, Univ of Maryland, College Park VL - UMIACS-TR-95-39 UR - http://drum.lib.umd.edu/handle/1903/714 ER - TY - JOUR T1 - An optimal algorithm for approximate nearest neighbor searching fixed dimensions JF - Journal of the ACM (JACM) Y1 - 1998 A1 - Arya,Sunil A1 - Mount, Dave A1 - Netanyahu,Nathan S. A1 - Silverman,Ruth A1 - Wu,Angela Y. KW - Approximation algorithms KW - Box-decomposition trees KW - closet-point queries KW - nearest neighbor searching KW - post-office problem KW - priority search AB - Consider a set of S of n data points in real d-dimensional space, Rd, where distances are measured using any Minkowski metric. In nearest neighbor searching, we preprocess S into a data structure, so that given any query point q ∈ Rd, is the closest point of S to q can be reported quickly. Given any positive real &egr;, data point p is a (1 +&egr;)-approximate nearest neighbor of q if its distance from q is within a factor of (1 + &egr;) of the distance to the true nearest neighbor. We show that it is possible to preprocess a set of n points in Rd in O(dn log n) time and O(dn) space, so that given a query point q ∈ Rd, and &egr; > 0, a (1 + &egr;)-approximate nearest neighbor of q can be computed in O(cd, &egr; log n) time, where cd,&egr;≤d 1 + 6d/e;d is a factor depending only on dimension and &egr;. In general, we show that given an integer k ≥ 1, (1 + &egr;)-approximations to the k nearest neighbors of q can be computed in additional O(kd log n) time. VL - 45 SN - 0004-5411 UR - http://doi.acm.org/10.1145/293347.293348 CP - 6 M3 - 10.1145/293347.293348 ER - TY - CONF T1 - Partial online cycle elimination in inclusion constraint graphs T2 - ACM SIGPLAN Conference on Programming Language Design and Implementation (PLDI) Y1 - 1998 A1 - Aiken,A. A1 - Fhndrich,M. A1 - Foster, Jeffrey S. A1 - Su,Z. JA - ACM SIGPLAN Conference on Programming Language Design and Implementation (PLDI) ER - TY - CONF T1 - Performance measurement using low perturbation and high precision hardware assists T2 - , The 19th IEEE Real-Time Systems Symposium, 1998. Proceedings Y1 - 1998 A1 - Mink, A. A1 - Salamon, W. A1 - Hollingsworth, Jeffrey K A1 - Arunachalam, R. KW - Clocks KW - Computerized monitoring KW - Counting circuits KW - Debugging KW - Hardware KW - hardware performance monitor KW - high precision hardware assists KW - low perturbation KW - measurement KW - MPI message passing library KW - MultiKron hardware performance monitor KW - MultiKron PCI KW - NIST KW - online performance monitoring tools KW - Paradyn parallel performance measurement tools KW - PCI bus slot KW - performance bug KW - performance evaluation KW - performance measurement KW - program debugging KW - program testing KW - real-time systems KW - Runtime KW - Timing AB - We present the design and implementation of MultiKron PCI, a hardware performance monitor that can be plugged into any computer with a free PCI bus slot. The monitor provides a series of high-resolution timers, and the ability to monitor the utilization of the PCI bus. We also demonstrate how the monitor can be integrated with online performance monitoring tools such as the Paradyn parallel performance measurement tools to improve the overhead of key timer operations by a factor of 25. In addition, we present a series of case studies using the MultiKron hardware performance monitor to measure and tune high-performance parallel completing applications. By using the monitor, we were able to find and correct a performance bug in a popular implementation of the MPI message passing library that caused some communication primitives to run at one half their potential speed JA - , The 19th IEEE Real-Time Systems Symposium, 1998. Proceedings PB - IEEE SN - 0-8186-9212-X M3 - 10.1109/REAL.1998.739771 ER - TY - JOUR T1 - The PLAN system for building Active Networks JF - University of Pennsylvania (February 27, 1998) Y1 - 1998 A1 - Hicks, Michael W. A1 - Kakkar,P. A1 - Moore,J. T A1 - Gunter,C. A A1 - Alexander,D. S A1 - Nettles,S. ER - TY - JOUR T1 - Safety and security of programmable network infrastructures JF - IEEE Communications Magazine Y1 - 1998 A1 - Alexander,S. A1 - Arbaugh, William A. A1 - Keromytis,A. D A1 - Smith,J. M KW - Access control KW - error protection KW - IP networks KW - Multicast protocols KW - network architecture KW - network operating systems KW - network service model KW - operating system KW - Power system dynamics KW - Power system modeling KW - Power system reliability KW - programmable languages KW - programmable network infrastructures KW - programming languages KW - Proposals KW - Protection KW - reliability properties KW - Safety KW - Secure Active Network Environment KW - Security KW - security of data KW - service creation KW - service providers KW - Switches KW - telecommunication computing KW - telecommunication network reliability KW - Web and internet services AB - Safety and security are two reliability properties of a system. A “safe” system provides protection against errors of trusted users, while a “secure” system protects against errors introduced by untrusted users. There is considerable overlap between mechanisms to support each property. Requirements for rapid service creation have stimulated the development of programmable network infrastructures, where end users or service providers can customize the properties of a network infrastructure while it continues to operate. A central concern of potential users of such systems is their reliability and, most specifically, their safety and security. In this article we explain the impact the network service model and architecture have on safety and security, and provide a model with which policies can be translated into restrictions of a general system. We illustrate these ideas with the Secure Active Network Environment (SANE) architecture, which provides a means of controlling access to the functions provided by any programmable infrastructure VL - 36 SN - 0163-6804 CP - 10 M3 - 10.1109/35.722141 ER - TY - JOUR T1 - Salient Frame Detection for Molecular Dynamics Simulations JF - Scientific Visualization: Interactions, Features, Metaphors Y1 - 1998 A1 - Kim,Y. A1 - Patro,R. A1 - Ip,C. Y A1 - O’Leary,D. P A1 - Anishkin,A. A1 - Sukharev,S. A1 - Varshney, Amitabh AB - Saliency-based analysis can be applied to time-varying 3D datasetsfor the purpose of summarization, abstraction, and motion analysis. As the sizes of time-varying datasets continue to grow, it becomes more and more difficult to comprehend vast amounts of data and information in a short period of time. Au- tomatically generated thumbnail images and previewing of time-varying datasets can help viewers explore and understand the datasets significantly faster as well as provide new insights. In this paper, we introduce a novel method for detect- ing salient frames for molecular dynamics simulations. Our method effectively detects crucial transitions in simulated mechanosensitive ion channel (MscS), in agreement with experimental data. VL - 2 ER - TY - JOUR T1 - Scheduling Aperiodic and Sporadic Tasks in Hard Real-Time Systems JF - Technical Reports from UMIACS, UMIACS-TR-97-44 Y1 - 1998 A1 - Choi,Seonho A1 - Agrawala, Ashok K. KW - Technical Report AB - The stringent timing constraints as well as the functional correctnessare essential requirements of hard real-time systems. In such systems, scheduling plays a very important role in satisfying these constraints. The priority based scheduling schemes have been used commonly due to the simplicity of the scheduling algorithm. However, in the presence of task interdependencies and complex timing constraints, such scheduling schemes may not be appropriate due to the lack of an efficient mechanism to schedule them and to carry out the schedulability analysis. In contrast, the time based scheduling scheme may be used to schedule a set of tasks with greater degree of schedulability achieved at a cost of higher complexity of off-line scheduling. One of the drawbacks of currently available scheduling schemes, however, is known to be their inflexibility in dynamic environments where dynamic processes exist, such as aperiodic and sporadic processes. We develop and analyze scheduling schemes which efficiently provide the flexibility required in real-time systems for scheduling processes arriving dynamically. This enables static hard periodic processes and dynamic processes(aperiodic or sporadic) to be jointly scheduled. (Also cross-referenced as UMIACS-TR-97-44) UR - http://drum.lib.umd.edu/handle/1903/900 ER - TY - JOUR T1 - A secure active network environment architecture: realization in SwitchWare JF - IEEE Network Y1 - 1998 A1 - Alexander,D. S A1 - Arbaugh, William A. A1 - Keromytis,A. D A1 - Smith,J. M KW - access protocols KW - AEGIS secure bootstrap architecture KW - architecture KW - Authentication KW - Collaboration KW - Communication switching KW - dynamic integrity checks KW - extended LAN KW - Functional programming KW - implementation KW - integrity KW - Intelligent networks KW - IP networks KW - Local area networks KW - network infrastructure KW - network infrastructures KW - network operating systems KW - network-level solutions KW - node KW - node-to-node authentication KW - packet switching KW - Proposals KW - ramming system KW - SANE KW - secure active network environment architecture KW - security of data KW - Switches KW - SwitchWare KW - trusted state KW - Web and internet services AB - An active network is a network infrastructure which is programmable on a per-user or even per-packet basis. Increasing the flexibility of such network infrastructures invites new security risks. Coping with these security risks represents the most fundamental contribution of active network research. The security concerns can be divided into those which affect the network as a whole and those which affect individual elements. It is clear that the element problems must be solved first, since the integrity of network-level solutions will be based on trust in the network elements. In this article we describe the architecture and implementation of a secure active network environment (SANE), which we believe provides a basis for implementing secure network-level solutions. We guarantee that a node begins operation in a trusted state with the AEGIS secure bootstrap architecture. We guarantee that the system remains in a trusted state by applying dynamic integrity checks in the network element's runtime system, using a novel naming system, and applying node-to-node authentication when needed. The construction of an extended LAN is discussed VL - 12 SN - 0890-8044 CP - 3 M3 - 10.1109/65.690960 ER - TY - JOUR T1 - Security for virtual private intranets JF - Computer Y1 - 1998 A1 - Arbaugh, William A. A1 - Davin,J. R A1 - Farber,D. J A1 - Smith,J. M KW - businesses KW - Clouds KW - Companies KW - core operating system components KW - cryptography KW - Data security KW - employee homes KW - encryption KW - functional roles KW - hard drive KW - Home computing KW - home working KW - integrity checking KW - Internet KW - Local area networks KW - multiple personalities KW - network authentication KW - network environment KW - operating system modifications KW - Operating systems KW - Roads KW - secure identity based lending KW - security management KW - security of data KW - shared applications KW - SIBL KW - single hardware platform KW - smart cards KW - symmetric algorithm KW - system partition KW - telecommuting KW - Teleworking KW - trust relationship KW - trustworthy system KW - virtual private intranets AB - As telecommuting grows, businesses must consider security when extending their network environment to employees' homes. Researchers at the University of Pennsylvania have addressed the problem with smart cards, operating system modifications, and network authentication. We note the distinction between trust and integrity: trust is determined through the verification of components and the dependencies among them, while integrity demonstrates that components haven't been modified. Thus integrity checking in a trustworthy system is about preserving an established trust or trust relationship. Our solution to the challenge of isolating functional roles that may share a single hardware platform is called secure identity based lending (SIBL). SIBL provides multiple personalities by partitioning the hard drive into n+1 partitions, where n is the number of supported personalities. All personalities use the system partition for core operating system components and shared applications. Each of the personalities is also associated with one of the remaining partitions, which are encrypted using a symmetric algorithm VL - 31 SN - 0018-9162 CP - 9 M3 - 10.1109/2.708450 ER - TY - CONF T1 - Self-calibration from image derivatives T2 - Sixth International Conference on Computer Vision, 1998 Y1 - 1998 A1 - Brodsky, T. A1 - Fermüller, Cornelia A1 - Aloimonos, J. KW - 3D-rotation KW - active vision KW - Calibration KW - CAMERAS KW - discrete motion KW - Encoding KW - Equations KW - image derivatives KW - image formation KW - image measurements KW - Image motion analysis KW - image motion fields KW - Image reconstruction KW - Image sequences KW - large video databases KW - Layout KW - Levenberg-Marquardt parameter estimation KW - linear pinhole-camera model KW - Motion estimation KW - Motion measurement KW - Optical computing KW - parameter estimation KW - projective transformation KW - rigidly moving camera KW - self-calibration KW - smoothness constraints KW - unknown calibration parameters AB - This study investigates the problem of estimating the calibration parameters from image motion fields induced by a rigidly moving camera with unknown calibration parameters, where the image formation is modeled with a linear pinhole-camera model. The equations obtained show the flow to be clearly separated into a component due to the translation and the calibration parameters and a component due to the rotation and the calibration parameters. A set of parameters encoding the latter component are linearly related to the flow, and from these parameters the calibration can be determined. However, as for discrete motion, in the general case it is not possible, to decouple image measurements from two frames only into their translational and rotational component. Geometrically, the ambiguity takes the form of a part of the rotational component being parallel to the translational component, and thus the scene can be reconstructed only up to a projective transformation. In general, for a full calibration at least four successive image frames are necessary with the 3D-rotation changing between the measurements. The geometric analysis gives rise to a direct self-calibration method that avoids computation of optical flow or point correspondences and uses only normal flow measurements. In this technique the direction of translation is estimated employing in a novel way smoothness constraints. Then the calibration parameters are estimated from the rotational components of several flow fields using Levenberg-Marquardt parameter estimation, iterative in the calibration parameters only. The technique proposed does not require calibration objects in the scene or special camera motions and it also avoids the computation of exact correspondence. This makes it suitable for the calibration of active vision systems which have to acquire knowledge about their intrinsic parameters while they perform other tasks, or as a tool for analyzing image sequences in large video databases JA - Sixth International Conference on Computer Vision, 1998 PB - IEEE SN - 81-7319-221-9 M3 - 10.1109/ICCV.1998.710704 ER - TY - JOUR T1 - Shape from video: Beyond the epipolar constraint JF - Proceedings of the DARPA Image Understanding Workshop Y1 - 1998 A1 - Brodsky, T. A1 - Fermüller, Cornelia A1 - Aloimonos, J. ER - TY - CHAP T1 - Simultaneous estimation of viewing geometry and structure T2 - Computer Vision — ECCV'98Computer Vision — ECCV'98 Y1 - 1998 A1 - Brodský,Tomáš A1 - Fermüller, Cornelia A1 - Aloimonos, J. ED - Burkhardt,Hans ED - Neumann,Bernd AB - Up to now, structure from motion algorithms proceeded in two well defined steps, where the first and most important step is recovering the rigid transformation between two views, and the subsequent step is using this transformation to compute the structure of the scene in view. This paper introduces a novel approach to structure from motion in which both aforementioned steps are accomplished in a synergistic manner. Existing approaches to 3D motion estimation are mostly based on the use of optic flow which however poses a problem at the locations of depth discontinuities. If we knew where depth discontinuities were, we could (using a multitude of approaches based on smoothness constraints) estimate accurately flow values for image patches corresponding to smooth scene patches; but to know the discontinuities requires solving the structure from motion problem first. In the past this dilemma has been addressed by improving the estimation of flow through sophisticated optimization techniques, whose performance often depends on the scene in view. In this paper we follow a different approach. The main idea is based on the interaction between 3D motion and shape which allows us to estimate the 3D motion while at the same time segmenting the scene. If we use a wrong 3D motion estimate to compute depth, then we obtain a distorted version of the depth function. The distortion, however, is such that the worse the motion estimate, the more likely we are to obtain depth estimates that are locally unsmooth, i.e., they vary more than the correct ones. Since local variability of depth is due either to the existence of a discontinuity or to a wrong 3D motion estimate, being able to differentiate between these two cases provides the correct motion, which yields the “smoothest” estimated depth as well as the image location of scene discontinuities. Although no optic flow values are computed, we show that our algorithm is very much related to minimizing the epipolar constraint and we present a number of experimental results with real image sequences indicating the robustness of the method. JA - Computer Vision — ECCV'98Computer Vision — ECCV'98 T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 1406 SN - 978-3-540-64569-6 UR - http://dx.doi.org/10.1007/BFb0055677 ER - TY - JOUR T1 - The SwitchWare active network architecture JF - IEEE Network Y1 - 1998 A1 - Alexander,D. S A1 - Arbaugh, William A. A1 - Hicks, Michael W. A1 - Kakkar,P. A1 - Keromytis,A. D A1 - Moore,J. T A1 - Gunter,C. A A1 - Nettles,S. M A1 - Smith,J. M KW - active extensions KW - active packets KW - Authentication KW - Computer languages KW - Computer networks KW - cryptography KW - cryptography-based authentication KW - high-integrity base KW - integrity checking KW - IP networks KW - LAN interconnection KW - mobile programs KW - network operating systems KW - packet switching KW - programmable network infrastructure KW - programming languages KW - Protocols KW - Safety KW - safety requirements KW - scalability KW - secure active router infrastructure KW - Security KW - security requirements KW - services KW - strong type checking KW - Switches KW - SwitchWare active network architecture KW - telecommunication network routing KW - Tin KW - usability KW - verification techniques AB - Active networks must balance the flexibility of a programmable network infrastructure against the safety and security requirements inherent in sharing that infrastructure. Furthermore, this balance must be achieved while maintaining the usability of the network. The SwitchWare active network architecture is a novel approach to achieving this balance using three layers: active packets, which contain mobile programs that replace traditional packets; active extensions, which provide services on the network elements and can be dynamically loaded; and a secure active router infrastructure, which forms a high-integrity base on which the security of the other layers depends. In addition to integrity checking and cryptography-based authentication, security in our architecture depends heavily on verification techniques from programming languages, such as strong type checking VL - 12 SN - 0890-8044 CP - 3 M3 - 10.1109/65.690959 ER - TY - JOUR T1 - The switchware active network implementation JF - The ML Workshop, International Conference on Functional Programming (ICFP) Y1 - 1998 A1 - Alexander,D. S A1 - Hicks, Michael W. A1 - Kakkar,P. A1 - Keromytis,A. D A1 - Shaw,M. A1 - Moore,J. T A1 - Gunter,C. A A1 - Jim,T. A1 - Nettles,S. M A1 - Smith,J. M ER - TY - JOUR T1 - T2 JF - ACM SIGMOD Record Y1 - 1998 A1 - Chang,Chialin A1 - Acharya,Anurag A1 - Sussman, Alan A1 - Saltz,Joel VL - 27 SN - 01635808 UR - http://dl.acm.org/citation.cfm?id=273264 M3 - 10.1145/273244.273264 ER - TY - CONF T1 - Temporally determinate disk access (extended abstract): an experimental approach T2 - Proceedings of the 1998 ACM SIGMETRICS joint international conference on Measurement and modeling of computer systems Y1 - 1998 A1 - Aboutabl,Mohamed A1 - Agrawala, Ashok K. A1 - Decotignie,Jean-Dominique JA - Proceedings of the 1998 ACM SIGMETRICS joint international conference on Measurement and modeling of computer systems T3 - SIGMETRICS '98/PERFORMANCE '98 PB - ACM CY - New York, NY, USA SN - 0-89791-982-3 UR - http://doi.acm.org/10.1145/277851.277950 M3 - 10.1145/277851.277950 ER - TY - BOOK T1 - Trends in the Early Careers of Life Scientists Y1 - 1998 A1 - Tilghman,S A1 - Astin,HS A1 - Brinkley,W A1 - Chilton,MD A1 - Cummings, Michael P. A1 - Ehrenberg,RG A1 - Fox,MF A1 - Glenn,K A1 - Green,PJ A1 - Hans,S A1 - Kelman,A A1 - LaPidus,J A1 - Levin,B A1 - McIntosh,JR A1 - Riecken,H A1 - Stephen,PE PB - National Academy Press CY - Washington, DC ER - TY - JOUR T1 - Trends in the early careers of life scientists - Preface and executive summary JF - Mol Biol Cell Y1 - 1998 A1 - Tilghman,S A1 - Astin,HS A1 - Brinkley,W A1 - Chilton,MD A1 - Cummings, Michael P. A1 - Ehrenberg,RG A1 - Fox,MF A1 - Glenn,K A1 - Green,PJ A1 - Hans,S A1 - Kelman,A A1 - LaPidus,J A1 - Levin,B A1 - McIntosh,JR A1 - Riecken,H A1 - Stephen,PE VL - 9 CP - 11 ER - TY - JOUR T1 - Uncertainty propagation in model-based recognition JF - International Journal of Computer Vision Y1 - 1998 A1 - Alter,T. D. A1 - Jacobs, David W. AB - Robust recognition systems require a careful understanding of the effects of error in sensed features. In model-based recognition, matches between model features and sensed image features typically are used to compute a model pose and then project the unmatched model features into the image. The error in the image features results in uncertainty in the projected model features. We first show how error propagates when poses are based on three pairs of 3D model and 2D image points. In particular, we show how to simply and efficiently compute the distributed region in the image where an unmatched model point might appear, for both Gaussian and bounded error in the detection of image points, and for both scaled-orthographic and perspective projection models. Next, we provide geometric and experimental analyses to indicate when this linear approximation will succeed and when it will fail. Then, based on the linear approximation, we show how we can utilize Linear Programming to compute bounded propagated error regions for any number of initial matches. Finally, we use these results to extend, from two-dimensional to three-dimensional objects, robust implementations of alignment, interpretation-tree search, and transformation clustering. VL - 27 CP - 2 M3 - 10.1023/A:1007989016491 ER - TY - CHAP T1 - The Video Yardstick T2 - Modelling and Motion Capture Techniques for Virtual EnvironmentsModelling and Motion Capture Techniques for Virtual Environments Y1 - 1998 A1 - Brodský,Tomáš A1 - Fermüller, Cornelia A1 - Aloimonos, J. ED - Magnenat-Thalmann,Nadia ED - Thalmann,Daniel AB - Given uncalibrated video sequences, how can we recover rich descriptions of the scene content, beyond two-dimensional (2D) measurements such as color/texture or motion fields — descriptions of shape and three-dimensional (3D) motion? This is the well known structure from motion (SFM) problem. Up to now, SFM algorithms proceeded in two well defined steps, where the first and most important step is recovering the rigid transformation between two views, and the subsequent step is using this transformation to compute the structure of the scene in view. This paper introduces a novel approach to structure from motion in which both steps are accomplished in a synergistic manner. It deals with the classical structure from motion problem considering a calibrated camera as well as the extension to an uncalibrated optical device. Existing approaches to estimation of the viewing geometry are mostly based on the use of optic flow, which, however, poses a problem at the locations of depth discontinuities. If we knew where depth discontinuities were, we could (using a multitude of approaches based on smoothness constraints) accurately estimate flow values for image patches corresponding to smooth scene patches; but to know the discontinuities requires solving the structure from motion problem first. In the past this dilemma has been addressed by improving the estimation of flow through sophisticated optimization techniques, whose performance often depends on the scene in view. In this paper we follow a different approach. We directly utilize the image derivatives and employ constraints which involve the 3D motion and shape of the scene, leading to a geometric and statistical estimation problem. The main idea is based on the interaction between 3D motion and shape which allows us to estimate the 3D motion while at the same time segmenting the scene. If we use a wrong 3D motion estimate to compute depth, we obtain a distorted version of the depth function. The distortion, however, is such that the worse the motion estimate, the more likely we are to obtain depth estimates that are locally unsmooth, i.e., they vary more than the correct ones. Since local variability of depth is due either to the existence of a discontinuity or to a wrong 3D motion estimate, being able to differentiate between these two cases provides the correct motion, which yields the “smoothest” estimated depth as well as the image locations of scene discontinuities. We analyze the new constraints introduced by our approach and show their relationship to the minimization of the epipolar constraint, which becomes a special case of our theory. Finally, we present a number of experimental results with real image sequences indicating the robustness of our method and the improvement over traditional methods. The resulting system is a video yardstick that can be applied to any video sequence to recover first the calibration parameters of the camera that captured the video and, subsequently, the structure of the scene. JA - Modelling and Motion Capture Techniques for Virtual EnvironmentsModelling and Motion Capture Techniques for Virtual Environments T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 1537 SN - 978-3-540-65353-0 UR - http://dx.doi.org/10.1007/3-540-49384-0_12 ER - TY - JOUR T1 - Viewing personal history records: A comparison of tabular format and graphical presentation using LifeLines JF - Behaviour & Information Technology Y1 - 1998 A1 - Alonso,Diane Lindwarm A1 - Rose,Anne A1 - Plaisant, Catherine A1 - Norman,Kent L AB - Thirty-six participants used a static version of either LifeLines, a graphical interface, or a tabular representation to answer questions about a database of temporal personal history information. Results suggest that overall the LifeLines representation led to much faster response times, primarily for questions which involved interval comparisons and making intercategorical connections. A 'first impression' test showed that LifeLines can reduce some of the biases of the tabular record summary. A post-experimental memory test led to significantly (p< 0.004) higher recall for LifeLines. Finally, simple interaction techniques are proposed to compensate for the problems of the static LifeLines display's ability to deal with precise dates, attribute coding and overlaps.Thirty-six participants used a static version of either LifeLines, a graphical interface, or a tabular representation to answer questions about a database of temporal personal history information. Results suggest that overall the LifeLines representation led to much faster response times, primarily for questions which involved interval comparisons and making intercategorical connections. A 'first impression' test showed that LifeLines can reduce some of the biases of the tabular record summary. A post-experimental memory test led to significantly (p< 0.004) higher recall for LifeLines. Finally, simple interaction techniques are proposed to compensate for the problems of the static LifeLines display's ability to deal with precise dates, attribute coding and overlaps. VL - 17 SN - 0144-929X UR - http://www.tandfonline.com/doi/abs/10.1080/014492998119328 CP - 5 M3 - 10.1080/014492998119328 ER - TY - CHAP T1 - What is computed by structure from motion algorithms? T2 - Computer Vision — ECCV'98 Y1 - 1998 A1 - Fermüller, Cornelia A1 - Aloimonos, J. ED - Burkhardt,Hans ED - Neumann,Bernd AB - In the literature we find two classes of algorithms which, on the basis of two views of a scene, recover the rigid transformation between the views and subsequently the structure of the scene. The first class contains techniques which require knowledge of the correspondence or the motion field between the images and are based on the epipolar constraint. The second class contains so-called direct algorithms which require knowledge about the value of the flow in one direction only and are based on the positive depth constraint. Algorithms in the first class achieve the solution by minimizing a function representing deviation from the epipolar constraint while direct algorithms find the 3D motion that, when used to estimate depth, produces a minimum number of negative depth values. This paper presents a stability analysis of both classes of algorithms. The formulation is such that it allows comparison of the robustness of algorithms in the two classes as well as within each class. Specifically, a general statistical model is employed to express the functions which measure the deviation from the epipolar constraint and the number of negative depth values, and these functions are studied with regard to their topographic structure, specifically as regards the errors in the 3D motion parameters at the places representing the minima of the functions. The analysis shows that for algorithms in both classes which estimate all motion parameters simultaneously, the obtained solution has an error such that the projections of the translational and rotational errors on the image plane are perpendicular to each other. Furthermore, the estimated projection of the translation on the image lies on a line through the origin and the projection of the real translation. JA - Computer Vision — ECCV'98 T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 1406 SN - 978-3-540-64569-6 UR - http://dx.doi.org/10.1007/BFb0055678 ER - TY - CONF T1 - Which shape from motion? T2 - Sixth International Conference on Computer Vision, 1998 Y1 - 1998 A1 - Fermüller, Cornelia A1 - Aloimonos, J. KW - 3D motion estimation KW - affine shape KW - Algorithm design and analysis KW - Computer vision KW - distorted version KW - distortion function KW - human visual space distortion KW - HUMANS KW - Image motion analysis KW - image representation KW - Information analysis KW - Layout KW - Motion analysis KW - Motion estimation KW - motion information KW - Psychology KW - rigid transformation KW - SHAPE KW - shape estimation KW - shape representations KW - State estimation KW - visual space AB - In a practical situation, the rigid transformation relating different views is recovered with errors. In such a case, the recovered depth of the scene contains errors, and consequently a distorted version of visual space is computed. What then are meaningful shape representations that can be computed from the images? The result presented in this paper states that if the rigid transformation between different views is estimated in a way that gives rise to a minimum number of negative depth values, then at the center of the image affine shape can be correctly computed. This result is obtained by exploiting properties of the distortion function. The distortion model turns out to be a very powerful tool in the analysis and design of 3D motion and shape estimation algorithms, and as a byproduct of our analysis we present a computational explanation of psychophysical results demonstrating human visual space distortion from motion information JA - Sixth International Conference on Computer Vision, 1998 PB - IEEE SN - 81-7319-221-9 M3 - 10.1109/ICCV.1998.710792 ER - TY - JOUR T1 - ANN: A library for approximate nearest neighbor searching JF - CGC 2nd Annual Fall Workshop on Computational Geometry Y1 - 1997 A1 - Mount, Dave A1 - Arya,S. ER - TY - CONF T1 - Approximating hyper-rectangles: learning and pseudo-random sets T2 - Proceedings of the twenty-ninth annual ACM symposium on Theory of computing Y1 - 1997 A1 - Auer,Peter A1 - Long,Philip M. A1 - Srinivasan, Aravind KW - approximations of distributions KW - derandomization KW - explicit constructions KW - machine learning KW - multiple-instance learning KW - PAC learning KW - pseudorandomness KW - Ramsey graphs KW - random graphs KW - rectangles KW - sample complexity JA - Proceedings of the twenty-ninth annual ACM symposium on Theory of computing T3 - STOC '97 PB - ACM CY - New York, NY, USA SN - 0-89791-888-6 UR - http://doi.acm.org/10.1145/258533.258611 M3 - 10.1145/258533.258611 ER - TY - CONF T1 - The confounding of translation and rotation in reconstruction from multiple views T2 - , 1997 IEEE Computer Society Conference on Computer Vision and Pattern Recognition, 1997. Proceedings Y1 - 1997 A1 - Fermüller, Cornelia A1 - Aloimonos, J. KW - 3D rigid motion KW - CAMERAS KW - ecological optics KW - Error correction KW - Image motion analysis KW - Image reconstruction KW - Layout KW - Motion analysis KW - Motion estimation KW - multiple views KW - Optical distortion KW - optimal configuration KW - optimal rotational error KW - planar retina KW - RETINA KW - rigid motion KW - ROTATION KW - scene structure KW - shape estimation KW - spherical retina KW - Stability analysis KW - structure-from-motion problem KW - translation AB - If 3D rigid motion is estimated with some error a distorted version of the scene structure will in turn be computed. Of computational interest are these regions in space where the distortions are such that the depths become negative, because in order to be visible the scene has to lie in front of the image. The stability analysis for the structure-from-motion problem presented in this paper investigates the optimal relationship between the errors in the estimated translational and rotational parameters of a rigid motion, that results in the estimation of a minimum number of negative depth values. The input used is the value of the flow along some direction, which is more general than optic flow or correspondence. For a planar retina it is shown that the optimal configuration is achieved when the projections of the translational and rotational errors on the image plane are perpendicular. Furthermore, the projection of the actual and the estimated translation lie on a line passing through the image center. For a spherical retina given a rotational error, the optimal translation is the correct one, while given a translational error. The optimal rotational error is normal to the translational one at an equal distance from the real and estimated translations. The proofs, besides illuminating the confounding of translation and rotation in structure from motion, have an important application to ecological optics, explaining differences of planar and spherical eye or camera designs in motion and shape estimation JA - , 1997 IEEE Computer Society Conference on Computer Vision and Pattern Recognition, 1997. Proceedings PB - IEEE SN - 0-8186-7822-4 M3 - 10.1109/CVPR.1997.609328 ER - TY - JOUR T1 - DIRECT MOTION PERCEPTION JF - Visual navigation: from biological systems to unmanned ground vehicles Y1 - 1997 A1 - Fermüller, Cornelia A1 - Aloimonos, J. ER - TY - CONF T1 - The distributed information search component (disco) and the world wide web T2 - Proc. of ACM SIGMOD Conf. on Management of Data Y1 - 1997 A1 - Naacke,H. A1 - Kapitskaia,O. A1 - Tomasic,A. A1 - Bonnet,P. A1 - Raschid, Louiqa A1 - Amouroux,R. JA - Proc. of ACM SIGMOD Conf. on Management of Data ER - TY - JOUR T1 - Editorial: Evaluation and assessment in software engineering JF - Information and Software Technology Y1 - 1997 A1 - Kitchenham,B. A1 - Brereton,P. A1 - Budgen,D. A1 - Linkman,S. A1 - Almstrum,V. L A1 - Pfleeger,S. L A1 - Zelkowitz, Marvin V A1 - Wallace,D. VL - 39 CP - 11 ER - TY - JOUR T1 - Families of Stationary Patterns Producing Illusory Movement: Insights into the Visual System JF - Proceedings of the Royal Society of London. Series B: Biological SciencesProc. R. Soc. Lond. B Y1 - 1997 A1 - Fermüller, Cornelia A1 - Pless,Robert A1 - Aloimonos, J. AB - A computational explanation of the illusory movement experienced upon extended viewing of Enigma, a static figure painted by Leviant, is presented. The explanation relies on a model for the interpretation of three–dimensional motion information contained in retinal motion measurements. This model shows that the Enigma figure is a special case of a larger class of figures exhibiting the same illusory movement and these figures are introduced here. Our explanation suggests that eye movements and/or accommodation changes cause weak retinal motion signals, which are interpreted by higher–level processes in a way that gives rise to these illusions, and proposes a number of new experiments to unravel the functional structure of the motion pathway. VL - 264 SN - 0962-8452, 1471-2954 UR - http://rspb.royalsocietypublishing.org/content/264/1383/795 CP - 1383 M3 - 10.1098/rspb.1997.0112 ER - TY - JOUR T1 - On the Geometry of Visual Correspondence JF - International Journal of Computer Vision Y1 - 1997 A1 - Fermüller, Cornelia A1 - Aloimonos, J. AB - Image displacement fields—optical flow fields, stereo disparity fields, normal flow fields—due to rigid motion possess a global geometric structure which is independent of the scene in view. Motion vectors of certain lengths and directions are constrained to lie on the imaging surface at particular loci whose location and form depends solely on the 3D motion parameters. If optical flow fields or stereo disparity fields are considered, then equal vectors are shown to lie on conic sections. Similarly, for normal motion fields, equal vectors lie within regions whose boundaries also constitute conics. By studying various properties of these curves and regions and their relationships, a characterization of the structure of rigid motion fields is given. The goal of this paper is to introduce a concept underlying the global structure of image displacement fields. This concept gives rise to various constraints that could form the basis of algorithms for the recovery of visual information from multiple views. VL - 21 SN - 0920-5691 UR - http://dx.doi.org/10.1023/A:1007951901001 CP - 3 ER - TY - CHAP T1 - The geometry of visual space distortion T2 - Algebraic Frames for the Perception-Action CycleAlgebraic Frames for the Perception-Action Cycle Y1 - 1997 A1 - Fermüller, Cornelia A1 - LoongFah Cheong A1 - Aloimonos, J. ED - Sommer,Gerald ED - Koenderink,Jan AB - The encounter of perception and action happens at the intermediate representations of space-time. In many of the computational models employed in the past, it has been assumed that a metric representation of physical space can be derived by visual means. Psychophysical experiments, as well as computational considerations, can convince us that the perception of space and shape has a much more complicated nature, and that only a distorted version of actual, physical space can be computed. This paper develops a computational geometric model that explains why such distortion might take place. The basic idea is that, both in stereo and motion, we perceive the world from multiple views. Given the rigid transformation between the views and the properties of the image correspondence, the depth of the scene can be obtained. Even a slight error in the rigid transformation parameters causes distortion of the computed depth of the scene. The unified framework introduced here describes this distortion in computational terms. We characterize the space of distortions by its level sets, that is, we characterize the systematic distortion via a family of iso-distortion surfaces which describes the locus over which depths are distorted by some multiplicative factor. Clearly, functions of the distorted space exhibiting some sort of invariance, produce desirable representations for biological and artificial systems [13]. Given that humans' estimation of egomotion or estimation of the extrinsic parameters of the stereo apparatus is likely to be imprecise, the framework is used to explain a number of psychophysical experiments on the perception of depth from motion or stereo. JA - Algebraic Frames for the Perception-Action CycleAlgebraic Frames for the Perception-Action Cycle T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 1315 SN - 978-3-540-63517-8 UR - http://dx.doi.org/10.1007/BFb0017872 ER - TY - JOUR T1 - Improved parallel approximation of a class of integer programming problems JF - Algorithmica Y1 - 1997 A1 - Alon,N. A1 - Srinivasan, Aravind AB - We present a method to derandomize RNC algorithms, converting them to NC algorithms. Using it, we show how to approximate a class of NP-hard integer programming problems in NC , to within factors better than the current-best NC algorithms (of Berger and Rompel and Motwani et al. ); in some cases, the approximation factors are as good as the best-known sequential algorithms, due to Raghavan. This class includes problems such as global wire-routing in VLSI gate arrays and a generalization of telephone network planning in SONET rings. Also for a subfamily of the “packing” integer programs, we provide the first NC approximation algorithms; this includes problems such as maximum matchings in hypergraphs, and generalizations. The key to the utility of our method is that it involves sums of superpolynomially many terms, which can however be computed in NC ; this superpolynomiality is the bottleneck for some earlier approaches, due to Berger and Rompel and Motwani et al. VL - 17 SN - 0178-4617 UR - http://dx.doi.org/10.1007/BF02523683 CP - 4 ER - TY - JOUR T1 - A Language Identification Application Built on the Java Client/Server Platform JF - From Research to Commercial Applications: Making NLP Work in Practice Y1 - 1997 A1 - Adams,G. A1 - Resnik, Philip ER - TY - JOUR T1 - Local Rules for Protein Folding on a Triangular Lattice and Generalized Hydrophobicity in the HP Model JF - Journal of Computational Biology Y1 - 1997 A1 - Agarwala,Richa A1 - Batzoglou,Serafim A1 - DančíK,Vlado A1 - Decatur,Scott E. A1 - Hannenhalli, Sridhar A1 - Farach,Martin A1 - Muthukrishnan,S. A1 - Skiena,Steven AB - We consider the problem of determining the three-dimensional folding of a protein given its one-dimensional amino acid sequence. We use the HP model for protein folding proposed by Dill (1985), which models protein as a chain of amino acid residues that are either hydrophobic or polar, and hydrophobic interactions are the dominant initial driving force for the protein folding. Hart and Istrail (1996a) gave approximation algorithms for folding proteins on the cubic lattice under the HP model. In this paper, we examine the choice of a lattice by considering its algorithmic and geometric implications and argue that the triangular lattice is a more reasonable choice. We present a set of folding rules for a triangular lattice and analyze the approximation ratio they achieve. In addition, we introduce a generalization of the HP model to account for residues having different levels of hydrophobicity. After describing the biological foundation for this generalization, we show that in the new model we are able to achieve similar constant factor approximation guarantees on the triangular lattice as were achieved in the standard HP model. While the structures derived from our folding rules are probably still far from biological reality, we hope that having a set of folding rules with different properties will yield more interesting folds when combined. VL - 4 SN - 1066-5277, 1557-8666 UR - http://www.liebertonline.com/doi/abs/10.1089/cmb.1997.4.275 CP - 3 M3 - 10.1089/cmb.1997.4.275 ER - TY - JOUR T1 - Optimized software synthesis for synchronous dataflow JF - Proceedings of the ASAP97 Y1 - 1997 A1 - Bhattacharyya, Shuvra S. A1 - America,H. ER - TY - CHAP T1 - Regulation of Cable Television T2 - The Froehlich/Kent Encyclopedia of Telecommunications: Volume 15-Radio Astronomy to Submarine Cable SystemsThe Froehlich/Kent Encyclopedia of Telecommunications: Volume 15-Radio Astronomy to Submarine Cable Systems Y1 - 1997 A1 - Agrawala, Ashok K. A1 - CILINGIROGLU,A. A1 - Lee,S. JA - The Froehlich/Kent Encyclopedia of Telecommunications: Volume 15-Radio Astronomy to Submarine Cable SystemsThe Froehlich/Kent Encyclopedia of Telecommunications: Volume 15-Radio Astronomy to Submarine Cable Systems VL - 15 ER - TY - JOUR T1 - Run-time and compiler support for programming in adaptive parallel environments JF - Scientific Programming Y1 - 1997 A1 - Edjlali,G. A1 - Agrawal,G. A1 - Sussman, Alan A1 - Humphries,J. A1 - Saltz, J. VL - 6 CP - 2 ER - TY - CONF T1 - A secure and reliable bootstrap architecture T2 - , 1997 IEEE Symposium on Security and Privacy, 1997. Proceedings Y1 - 1997 A1 - Arbaugh, William A. A1 - Farber,D. J A1 - Smith,J. M KW - active networks KW - AEGIS architecture KW - bootstrap architecture KW - Computer architecture KW - computer bootstrapping KW - data integrity KW - Distributed computing KW - Hardware KW - hardware validity KW - initialization KW - integrity chain KW - integrity check failures KW - Internet KW - Internet commerce KW - IP networks KW - Laboratories KW - lower-layer integrity KW - Microprogramming KW - Operating systems KW - recovery process KW - reliability KW - robust systems KW - Robustness KW - Security KW - security of data KW - software reliability KW - system integrity guarantees KW - system recovery KW - transitions KW - Virtual machining AB - In a computer system, the integrity of lower layers is typically treated as axiomatic by higher layers. Under the presumption that the hardware comprising the machine (the lowest layer) is valid, the integrity of a layer can be guaranteed if and only if: (1) the integrity of the lower layers is checked and (2) transitions to higher layers occur only after integrity checks on them are complete. The resulting integrity “chain” inductively guarantees system integrity. When these conditions are not met, as they typically are not in the bootstrapping (initialization) of a computer system, no integrity guarantees can be made, yet these guarantees are increasingly important to diverse applications such as Internet commerce, security systems and “active networks”. In this paper, we describe the AEGIS architecture for initializing a computer system. It validates integrity at each layer transition in the bootstrap process. AEGIS also includes a recovery process for integrity check failures, and we show how this results in robust systems JA - , 1997 IEEE Symposium on Security and Privacy, 1997. Proceedings PB - IEEE SN - 0-8186-7828-3 M3 - 10.1109/SECPRI.1997.601317 ER - TY - JOUR T1 - Testing simple polygons JF - Computational Geometry Y1 - 1997 A1 - Arkin,Esther M. A1 - Belleville,Patrice A1 - Mitchell,Joseph S.B. A1 - Mount, Dave A1 - Romanik,Kathleen A1 - Salzberg,Steven A1 - Souvaine,Diane KW - probing KW - Testing KW - Verifying AB - We consider the problem of verifying a simple polygon in the plane using “test points”. A test point is a geometric probe that takes as input a point in Euclidean space, and returns “+” if the point is inside the object being probed or “−” if it is outside. A verification procedure takes as input a description of a target object, including its location and orientation, and it produces a set of test points that are used to verify whether a test object matches the description. We give a procedure for verifying an n-sided, non-degenerate, simple target polygon using 5n test points. This testing strategy works even if the test polygon has n + 1 vertices, and we show a lower bound of 3n + 1 test points for this case. We also give algorithms using O(n) test points for simple polygons that may be degenerate and for test polygons that may have up to n + 2 vertices. All of these algorithms work for polygons with holes. We also discuss extensions of our results to higher dimensions. VL - 8 SN - 0925-7721 UR - http://www.sciencedirect.com/science/article/pii/S0925772196000156 CP - 2 M3 - 10.1016/S0925-7721(96)00015-6 ER - TY - CONF T1 - Titan: a High-Performance Remote-sensing Database T2 - In Proceedings of the 1997 International Conference on Data Engineering Y1 - 1997 A1 - Bongki,C. C A1 - Chang,C. A1 - Moon,B. A1 - Acharya, A. A1 - Shock,C. A1 - Sussman, Alan A1 - Saltz, J. JA - In Proceedings of the 1997 International Conference on Data Engineering ER - TY - CHAP T1 - Toward motion picture grammars T2 - Computer Vision — ACCV'98Computer Vision — ACCV'98 Y1 - 1997 A1 - Bolle,Ruud A1 - Aloimonos, J. A1 - Fermüller, Cornelia ED - Chin,Roland ED - Pong,Ting-Chuen AB - We are interested in processing video data for the purpose of solving a variety of problems in video search, analysis, indexing, browsing and compression. Instead of concentrating on a particular problem, in this paper we present a framework for developing video applications. Our basic thesis is that video data can be represented at a higher level of abstraction as a string generated by a grammar, termed motion picture grammar. The rules of that grammar relate different spatiotemporal representations of the video content and, in particular, representations of action. JA - Computer Vision — ACCV'98Computer Vision — ACCV'98 T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 1352 SN - 978-3-540-63931-2 UR - http://dx.doi.org/10.1007/3-540-63931-4_228 ER - TY - JOUR T1 - Visual Navigation: Flies, Bees, and UGV's JF - Visual navigation: from biological systems to unmanned ground vehicles Y1 - 1997 A1 - Aloimonos, J. ER - TY - BOOK T1 - Visual navigation: from biological systems to unmanned ground vehicles Y1 - 1997 A1 - Aloimonos, J. PB - Lawrence Erlbaum ER - TY - JOUR T1 - Visual space distortion JF - Biological Cybernetics Y1 - 1997 A1 - Fermüller, Cornelia A1 - LoongFah Cheong A1 - Aloimonos, J. AB - We are surrounded by surfaces that we perceive by visual means. Understanding the basic principles behind this perceptual process is a central theme in visual psychology, psychophysics, and computational vision. In many of the computational models employed in the past, it has been assumed that a metric representation of physical space can be derived by visual means. Psychophysical experiments, as well as computational considerations, can convince us that the perception of space and shape has a much more complicated nature, and that only a distorted version of actual, physical space can be computed. This paper develops a computational geometric model that explains why such distortion might take place. The basic idea is that, both in stereo and motion, we perceive the world from multiple views. Given the rigid transformation between the views and the properties of the image correspondence, the depth of the scene can be obtained. Even a slight error in the rigid transformation parameters causes distortion of the computed depth of the scene. The unified framework introduced here describes this distortion in computational terms. We characterize the space of distortions by its level sets, that is, we characterize the systematic distortion via a family of iso-distortion surfaces which describes the locus over which depths are distorted by some multiplicative factor. Given that humans' estimation of egomotion or estimation of the extrinsic parameters of the stereo apparatus is likely to be imprecise, the framework is used to explain a number of psychophysical experiments on the perception of depth from motion or stereo. VL - 77 SN - 0340-1200 UR - http://dx.doi.org/10.1007/s004220050393 CP - 5 ER - TY - JOUR T1 - Accounting for boundary effects in nearest-neighbor searching JF - Discrete & Computational Geometry Y1 - 1996 A1 - Arya,S. A1 - Mount, Dave A1 - Narayan,O. AB - Given n data points ind-dimensional space, nearest-neighbor searching involves determining the nearest of these data points to a given query point. Most averagecase analyses of nearest-neighbor searching algorithms are made under the simplifying assumption thatd is fixed and thatn is so large relative tod thatboundary effects can be ignored. This means that for any query point the statistical distribution of the data points surrounding it is independent of the location of the query point. However, in many applications of nearest-neighbor searching (such as data compression by vector quantization) this assumption is not met, since the number of data pointsn grows roughly as 2 d .Largely for this reason, the actual performances of many nearest-neighbor algorithms tend to be much better than their theoretical analyses would suggest. We present evidence of why this is the case. We provide an accurate analysis of the number of cells visited in nearest-neighbor searching by the bucketing andk-d tree algorithms. We assumem dpoints uniformly distributed in dimensiond, wherem is a fixed integer ≥2. Further, we assume that distances are measured in theL ∞ metric. Our analysis is tight in the limit asd approaches infinity. Empirical evidence is presented showing that the analysis applies even in low dimensions. VL - 16 CP - 2 M3 - 10.1007/BF02716805 ER - TY - CHAP T1 - Conjugate Gradients and Related KMP Algorithms: The Beginnings T2 - Linear and Nonlinear Conjugate Gradient-Related MethodsLinear and Nonlinear Conjugate Gradient-Related Methods Y1 - 1996 A1 - O'Leary, Dianne P. ED - Adams,Loyce ED - Nazareth,J. L. JA - Linear and Nonlinear Conjugate Gradient-Related MethodsLinear and Nonlinear Conjugate Gradient-Related Methods PB - SIAM CY - Philadelphia ER - TY - CHAP T1 - Directions of motion fields are hardly ever ambiguous T2 - Computer Vision — ECCV '96Computer Vision — ECCV '96 Y1 - 1996 A1 - Brodsky, Tomas A1 - Fermüller, Cornelia A1 - Aloimonos, J. ED - Buxton,Bernard ED - Cipolla,Roberto AB - Recent literature [7, 10, 11, 9, 13, 17] provides a number of results regarding uniqueness aspects of motion fields and exact image displacements due to 3-D rigid motion. Here instead of the full motion field we consider only the direction of the motion field due to a rigid motion and ask what can we say about the three-dimensional motion information contained in it. This paper provides a geometric analysis of this question based solely on the fact that the depth of the surfaces in view is positive (i.e. that the surface in view is in front of the camera). With this analysis we thus offer a theoretical foundation for image constraints employing only the sign of flow in various directions and provide a solid basis for their utilization in addressing 3D dynamic vision problems. JA - Computer Vision — ECCV '96Computer Vision — ECCV '96 T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 1065 SN - 978-3-540-61123-3 UR - http://dx.doi.org/10.1007/3-540-61123-1_132 ER - TY - JOUR T1 - Early detection of independent motion from active control of normal image flow patterns JF - Systems, Man, and Cybernetics, Part B: Cybernetics, IEEE Transactions on Y1 - 1996 A1 - Sharma, R. A1 - Aloimonos, J. VL - 26 CP - 1 ER - TY - CONF T1 - Effect of chemical reactions on the decay of isotropic homogeneous turbulence T2 - AIAA Fluid Dynamics Conference Y1 - 1996 A1 - Aguirre,M A1 - Candler,G. V A1 - Martin, M.P AB - Direct numerical simulations, (DNS), are usedto simulate the decay of an isotopic, turbulent, chemically-reacting flow at high temperatures. The independent parameters that govern the physical pro- cess are introduced. The different effects from each of the parameters in the flow are explained by using the results from the DNS. It is found that there is a feedback mechanism between the chemical reactions and the turbulent motion. This feedback is positive for exothermic reactions and negative for endother- mic reactions. JA - AIAA Fluid Dynamics Conference CY - New Orleans, LA VL - 96 ER - TY - RPRT T1 - Estimation of time-dependent coverage Y1 - 1996 A1 - Arlat,D. P. M. C. J. A1 - Crouzet,Y. AB - It is well-known that the dependability that can be achieved by a fault-tolerant systemis particularly sensitive to both the asymptotic value of coverage and to the time distribution of coverage. However, most previous work on coverage evaluation by statistical processing of the results of fault-injection experiments has only been concerned with estimating asymptotic coverage. In this paper, we tackle the problem of estimating the parameters of models that also account for coverage latency. After discussing some data sets resulting from fault-injection experiments on practical systems, we propose a series of coverage latency models that might be considered to account for the observed phenomena in a system dependability evaluation. We consider both exponential and non-exponential models, and assess their pertinence by means of a sensitivity study. We confirm previous results that latency can have an extremely important effect on the achievable dependability. We also show that the shape of the latency distribution has only a minor impact in the practical case of systems with high asymptotic coverage. A simple action model based on an exponential latency distribution is therefore proposed. We show how worst-case confidence limits can be obtained for the parameters of this action model and study the effects of data truncation that are unavoidable in any practical measurements of latency. We conclude by a critical assessment of the proposed estimation technique and a demonstration of its application to practical data sets. PB - LAAS-CNRS: Laboratory for analysis and architecture of systems CY - Toulouse, France VL - 96466 UR - http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.48.8253&rep=rep1&type=pdf ER - TY - BOOK T1 - Interaction between 3D Shape and Motion: Theory and Applications Y1 - 1996 A1 - Fermüller, Cornelia A1 - Aloimonos, J. A1 - Cheong,L. AB - Research during the past few years has attempted to characterize the errors that arise in computing 3D motion (egomotion estimation) and in a scene's structure (structure from motion) from a sequence of images acquired by a moving sensor. This paper presents a new geometric framework that characterizes how the three-dimensional space recovered by a moving monocular observer, whose 3D motion is estimated with some error, is distorted. We characterize the space of distortions by its level sets, that is, by a family of iso-distortion surfaces, each of which describes the locus over which the depths of points in the scene are distorted by the same multiplicative factor. By analyzing the geometry of the regions where the distortion factor is negative, that is, where the visibility constraint is violated, we make explicit situations which are likely to give rise to ambiguities in motion estimation. We also apply our approach to a uniqueness analysis for 3D motion analysis from normal flow; we study the constraints on egomotion, object motion and depth for an independently moving object to be detectable by a moving observer; and we offer a quantitative account of the precision needed in an inertial sensor for accurate estimation of 3D motion. PB - Computer Vision Laboratory, University of Maryland ER - TY - RPRT T1 - MARUTI at ARDEC. Y1 - 1996 A1 - Agrawala, Ashok K. A1 - Tripathi,Satish K KW - *OPERATING SYSTEMS(COMPUTERS) KW - Computer architecture KW - COMPUTER PROGRAMMING AND SOFTWARE KW - CONTROL KW - Cooperation KW - DSSA(DOMAIN SPECIFIC SOFTWARE ARCHITECTURE) KW - GUN TURRETS. KW - HIGH FREQUENCY KW - Laboratories KW - REAL TIME KW - ROBOTICS KW - TEST BEDS AB - This is the final report of the effort undertaken at the University of Maryland, sponsored by DARPA under the DSSA (Domain Specific Software Architectures) program. The activities reported here required an active cooperation and collaboration of the US Army ARDEC (Automation and Robotics Laboratory) and the University of Maryland (Computer Science Department). The principal investigators have been developing a hard real time operating system, MARUTI, at the University of Maryland. The goal of this effort was to demonstrate the applicability and usefulness of this operating system for exercising PID control at high frequency on the ATB1000 testbed which has been used to simulate a gun turret. A MARUTI based PID controller which operates at 200 HZ and 400 HZ was successfully implemented to demonstrate this feasibility. PB - University of Maryland, College Park UR - http://stinet.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA315086 ER - TY - JOUR T1 - An on-line variable-length binary encoding of text JF - Information Sciences Y1 - 1996 A1 - Acharya,Tinku A1 - JaJa, Joseph F. AB - We present a methodology for on-line variable-length binary encoding of a dynamically growing set of integers. Our encoding maintains the prefix property that enables unique decoding of a string of integers from the set. In order to develop the formalism of this on-line binary encoding, we define a unique binary tree data structure called the “phase in binary tree.” To show the utility of this on-line variable-length binary encoding, we apply this methodology to encode the pointers generated by the LZW algorithm. The experimental results obtained illustrate the superior performance of our algorithm compared to the most widely used algorithms. This on-line variable-length binary encoding can be applied in other dictionary-based text compression schemes as well to effectively encode the output pointers to enhance the compression ratio. VL - 94 SN - 0020-0255 UR - http://www.sciencedirect.com/science/article/pii/0020025596000898 CP - 1–4 M3 - 10.1016/0020-0255(96)00089-8 ER - TY - JOUR T1 - Ordinal representations of visual space JF - Proc. Image Understanding Workshop Y1 - 1996 A1 - Fermüller, Cornelia A1 - Aloimonos, J. ER - TY - CONF T1 - Runtime coupling of data-parallel programs T2 - Proceedings of the 10th international conference on Supercomputing Y1 - 1996 A1 - Ranganathan,M. A1 - Acharya, A. A1 - Edjlali,G. A1 - Sussman, Alan A1 - Saltz, J. JA - Proceedings of the 10th international conference on Supercomputing ER - TY - CONF T1 - Simplification envelopes T2 - Proceedings of the 23rd annual conference on Computer graphics and interactive techniques Y1 - 1996 A1 - Cohen,Jonathan A1 - Varshney, Amitabh A1 - Manocha,Dinesh A1 - Turk,Greg A1 - Weber,Hans A1 - Agarwal,Pankaj A1 - Brooks,Frederick A1 - Wright,William KW - geometric modeling KW - hierarchical approximation KW - levels-of-detail generation KW - model simplification KW - offsets KW - shape approximation JA - Proceedings of the 23rd annual conference on Computer graphics and interactive techniques T3 - SIGGRAPH '96 PB - ACM CY - New York, NY, USA SN - 0-89791-746-4 UR - http://doi.acm.org/10.1145/237170.237220 M3 - 10.1145/237170.237220 ER - TY - CHAP T1 - Spatiotemporal representations for visual navigation T2 - Computer Vision — ECCV '96Computer Vision — ECCV '96 Y1 - 1996 A1 - LoongFah Cheong A1 - Fermüller, Cornelia A1 - Aloimonos, J. ED - Buxton,Bernard ED - Cipolla,Roberto AB - The study of visual navigation problems requires the integration of visual processes with motor control. Most essential in approaching this integration is the study of appropriate spatio-temporal representations which the system computes from the imagery and which serve as interfaces to all motor activities. Since representations resulting from exact quantitative reconstruction have turned out to be very hard to obtain, we argue here for the necessity of representations which can be computed easily, reliably and in real time and which recover only the information about the 3D world which is really needed in order to solve the navigational problems at hand. In this paper we introduce a number of such representations capturing aspects of 3D motion and scene structure which are used for the solution of navigational problems implemented in visual servo systems. In particular, the following three problems are addressed: (a) to change the robot's direction of motion towards a fixed direction, (b) to pursue a moving target while keeping a certain distance from the target, and (c) to follow a wall-like perimeter. The importance of the introduced representations lies in the following: – They can be extracted using minimal visual information, in particular the sign of flow measurements or the the first order spatiotemporal derivatives of the image intensity function. In that sense they are direct representations needing no intermediate level of computation such as correspondence. – They are global in the sense that they represent how three-dimensional information is globally encoded in them. Thus, they are robust representations since local errors do not affect them. – Usually, from sequences of images, three-dimensional quantities such as motion and shape are computed and used as input to control processes. The representations discussed here are given directly as input to the control procedures, thus resulting in a real time solution. JA - Computer Vision — ECCV '96Computer Vision — ECCV '96 T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 1064 SN - 978-3-540-61122-6 UR - http://dx.doi.org/10.1007/BFb0015577 ER - TY - CHAP T1 - On stratified sampling for high coverage estimations T2 - Dependable Computing — EDCC-2 Y1 - 1996 A1 - Powell,David A1 - Michel Cukier A1 - Arlat,Jean ED - Hlawiczka,Andrzej ED - Silva,João ED - Simoncini,Luca KW - Computer science AB - This paper addresses the problem of estimating the coverage of a fault tolerance mechanism through statistical processing of observations collected in faultinjection experiments. In an earlier paper, several techniques for sampling the fault/activity input space of a fault tolerance mechanism were presented. Various estimators based on simple sampling in the whole space and stratified sampling in a partitioned space were studied; confidence limits were derived based on a normal approximation. In this paper, the validity of this approximation is analyzed, especially for high coverage systems. The theory of confidence regions is then introduced to estimate the coverage without approximation when, for practical reasons, stratification is used. Three statistics are considered for defining confidence regions. It is shown that one of these statistics — a vectorial statistic — is often more conservative than the other two. However, only the vectorial statistic is computationally tractable. The results obtained are compared with those based on approximation by means of three hypothetical example systems. JA - Dependable Computing — EDCC-2 T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 1150 SN - 978-3-540-61772-3 UR - http://www.springerlink.com/content/7t2w2u472601h730/abstract/ ER - TY - JOUR T1 - The synthesis of vision and action JF - Exploratory vision: the active eye Y1 - 1996 A1 - Fermüller, Cornelia A1 - Aloimonos, J. ER - TY - CONF T1 - Tuning the performance of I/O-intensive parallel applications T2 - Proceedings of the fourth workshop on I/O in parallel and distributed systems: part of the federated computing research conference Y1 - 1996 A1 - Acharya, A. A1 - Uysal, M. A1 - Bennett, R. A1 - Mendelson, A. A1 - Beynon, M. A1 - Hollingsworth, Jeffrey K A1 - Saltz, J. A1 - Sussman, Alan JA - Proceedings of the fourth workshop on I/O in parallel and distributed systems: part of the federated computing research conference ER - TY - CHAP T1 - Video representations T2 - Recent Developments in Computer Vision Y1 - 1996 A1 - Bolle,Ruud A1 - Aloimonos, J. A1 - Fermüller, Cornelia ED - Li,Stan ED - Mital,Dinesh ED - Teoh,Eam ED - Wang,Han JA - Recent Developments in Computer Vision T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 1035 SN - 978-3-540-60793-9 UR - http://dx.doi.org/10.1007/3-540-60793-5_60 ER - TY - CONF T1 - Where is information visualization technology going? T2 - Proceedings of the 9th annual ACM symposium on User interface software and technology Y1 - 1996 A1 - Hascoët-Zizi,Mountaz A1 - Ahlberg,Chris A1 - Korfhage,Robert A1 - Plaisant, Catherine A1 - Chalmers,Matthew A1 - Rao,Ramana JA - Proceedings of the 9th annual ACM symposium on User interface software and technology T3 - UIST '96 PB - ACM CY - New York, NY, USA SN - 0-89791-798-7 UR - http://doi.acm.org/10.1145/237091.237101 M3 - 10.1145/237091.237101 ER - TY - CONF T1 - 3D motion representations in visual servo control T2 - Proceedings of International Symposium on Computer Vision, 1995 Y1 - 1995 A1 - Fermüller, Cornelia A1 - LoongFah Cheong A1 - Aloimonos, J. KW - 3D motion representations KW - autonomous behavior KW - CAMERAS KW - computational effort KW - Computer vision KW - dynamic imagery KW - global spatiotemporal representations KW - image representation KW - Mobile robots KW - motion control KW - Navigation KW - navigational problems KW - Optical computing KW - Robot kinematics KW - Robot sensing systems KW - robot vision KW - Robot vision systems KW - Robotics and automation KW - servomechanisms KW - Servosystems KW - Spatiotemporal phenomena KW - vision-guided robotics KW - visual information KW - visual servo control KW - visual servoing AB - A new approach to visual servoing and vision-guided robotics is introduced. This approach uses visual information for autonomous behavior. It amounts to using robust, global spatiotemporal representations easily extracted from the dynamic imagery. Specifically, the geometrical patterns of normal flows are used as the input to the servo mechanism. It is shown that the positions of these patterns are related to the three dimensional motion parameters. By locating the positions of these patterns, we can solve a variety of navigational problems with little computational effort JA - Proceedings of International Symposium on Computer Vision, 1995 PB - IEEE SN - 0-8186-7190-4 M3 - 10.1109/ISCV.1995.476978 ER - TY - CONF T1 - Approximate range searching T2 - Proceedings of the eleventh annual symposium on Computational geometry Y1 - 1995 A1 - Arya,Sunil A1 - Mount, Dave JA - Proceedings of the eleventh annual symposium on Computational geometry T3 - SCG '95 PB - ACM CY - New York, NY, USA SN - 0-89791-724-3 UR - http://doi.acm.org/10.1145/220279.220298 M3 - 10.1145/220279.220298 ER - TY - BOOK T1 - Artificial Intelligence: Theory and Practice Y1 - 1995 A1 - Dean, Thomas L. A1 - ALLEN, JAMES AUTOR A1 - Aloimonos, J. KW - Computers / Expert Systems KW - Computers / Intelligence (AI) & Semantics AB - This book provides a detailed understanding of the broad issues in artificial intelligence and a useful survey of current AI technology. The author delivers broad coverage of innovative representational techniques, including neural networks, image processing, and probabilistic reasoning, alongside the traditional methods of symbolic reasoning. AI algorithms are described in detailed prose in the text and fully implemented in LISP at the ends of chapters. A stand-alone LISP chapter makes an excellent reference and refresher. Each chapter includes a detailed description of an AI application. PB - Benjamin/Cummings Pub. SN - 9780805325478 ER - TY - JOUR T1 - Automatic generation of multiresolution for polygonal models JF - First Workshop on Simulation and Interaction in Virtual Environments Y1 - 1995 A1 - Varshney, Amitabh A1 - Agarwal,P. A1 - Brooks,F. A1 - Wright,W. A1 - Weber,H. ER - TY - JOUR T1 - cDNA expressed sequence tags of Trypanosoma brucei rhodesiense provide new insights into the biology of the parasite JF - Molecular and Biochemical Parasitology Y1 - 1995 A1 - El‐Sayed, Najib M. A1 - Alarcon,Clara M. A1 - Beck,John C. A1 - Sheffield,Val C. A1 - Donelson,John E. KW - cDNA KW - Expressed sequence tag KW - Trypanosoma brucei rhodesiense AB - A total of 518 expressed sequence tags (ESTs) have been generated from clones randomly selected from a cDNA library and a spliced leader sub-library of a Trypanosoma brucei rhodesiense bloodstream clone. 205 (39%) of the clones were identified based on matches to 113 unique genes in the public databases. Of these, 71 cDNAs display significant similarities to genes in unrelated organisms encoding metabolic enzymes, signal transduction proteins, transcription factors, ribosomal proteins, histones, a proliferation-associated protein and thimet oligopeptidase, among others. 313 of the cDNAs are not related to any other sequences in the databases. These cDNA ESTs provide new avenues of research for exploring both the novel trypanosome-specific genes and the genome organization of this parasite, as well as a resource for identifying trypanosome homologs to genes expressed in other organisms. VL - 73 SN - 0166-6851 UR - http://www.sciencedirect.com/science/article/pii/016668519500098L CP - 1-2 M3 - 16/0166-6851(95)00098-L ER - TY - JOUR T1 - Crystallization and preliminary X-ray investigation of the recombinant Trypanosoma brucei rhodesiense calmodulin JF - Proteins: Structure, Function, and Bioinformatics Y1 - 1995 A1 - El‐Sayed, Najib M. A1 - Patton,C. L A1 - Harkins,P. C A1 - Fox,R. O A1 - Anderson,K. VL - 21 CP - 4 ER - TY - CONF T1 - Data parallel programming in an adaptive environment T2 - Parallel Processing Symposium, 1995. Proceedings., 9th International Y1 - 1995 A1 - Edjlali,G. A1 - Agrawal,G. A1 - Sussman, Alan A1 - Saltz, J. JA - Parallel Processing Symposium, 1995. Proceedings., 9th International ER - TY - JOUR T1 - Direct Perception of Three-Dimensional Motion from Patterns of Visual Motion JF - ScienceScience Y1 - 1995 A1 - Fermüller, Cornelia A1 - Aloimonos, J. AB - Measurements of retinal motion along a set of predetermined orientations on the retina of a moving system give rise to global patterns. Because the form and location of these patterns depend purely on three-dimensional (3D) motion, the effects of 3D motion and scene structure on image motion can be globally separated. The patterns are founded on easily derivable image measurements that depend only on the sign of image motion and do not require information about optical flow. The computational theory presented here explains how the self-motion of a system can be estimated by locating these patterns. VL - 270 SN - 0036-8075, 1095-9203 UR - http://www.sciencemag.org/content/270/5244/1973 CP - 5244 M3 - 10.1126/science.270.5244.1973 ER - TY - RPRT T1 - Enhancing LZW Coding Using a Variable-Length Binary Encoding Y1 - 1995 A1 - Acharya,Tinku A1 - JaJa, Joseph F. KW - algorithms KW - data compression KW - Systems Integration Methodology AB - We present here a methodology to enhance the LZW coding for text compression using a variable-length binary encoding scheme. The basic principle of this encoding is based on allocating a set of prefix codes to a set of integers growing dynamically. The prefix property enables unique decoding of a string of elements from this set. We presented the experimental results to show the effectiveness of this variable-length binary encoding scheme. PB - Institute for Systems Research, University of Maryland, College Park VL - ISR-TR-1995-70 UR - http://drum.lib.umd.edu/handle/1903/5654 ER - TY - CONF T1 - Euclidean spanners: short, thin, and lanky T2 - Proceedings of the twenty-seventh annual ACM symposium on Theory of computing Y1 - 1995 A1 - Arya,Sunil A1 - Das,Gautam A1 - Mount, Dave A1 - Salowe,Jeffrey S. A1 - Smid,Michiel JA - Proceedings of the twenty-seventh annual ACM symposium on Theory of computing T3 - STOC '95 PB - ACM CY - New York, NY, USA SN - 0-89791-718-9 UR - http://doi.acm.org/10.1145/225058.225191 M3 - 10.1145/225058.225191 ER - TY - RPRT T1 - Generating levels of detail for large-scale polygonal models Y1 - 1995 A1 - Varshney, Amitabh A1 - Agarwal,P. K A1 - Brooks Jr,F. P A1 - Wright,W. V A1 - Weber,H. AB - We present an e cient algorithm for generating various levels-of-detail approximations for agiven polygonal model. Our algorithm guarantees that all points of an approximation are within a user-speci able distance from the original model and all points of the original model are within a distance from the approximation. Each approximation attempts to minimize the total number of polygons required to satisfy the previous constraint. We show how the problem of generating levels- of-detail approximations reduces to the classic set partition problem. The various approximations are guaranteed to be topologically consistent with the input polygonal model. The approximations can be constrained by the user to preserve any desired edges of the input model. We also propose a method to compute an estimate of the quality of the approximation generated by our algorithm with respect to the optimal approximation satisfying the same constraints. We have implemented our algorithm and have obtained experimental results of multiresolution hierarchy generation on over a thousand polygonal objects from a CAD model of a notional submarine. PB - Department of Computer Science, Duke University, North Carolina VL - CS-1995-20 ER - TY - CONF T1 - Global rigidity constraints in image displacement fields T2 - , Fifth International Conference on Computer Vision, 1995. Proceedings Y1 - 1995 A1 - Fermüller, Cornelia A1 - Aloimonos, J. KW - 3D motion parameters KW - algorithms KW - Automation KW - Computer science KW - Computer vision KW - conic sections KW - curves KW - equal vectors KW - Fluid flow measurement KW - global geometric structure KW - global rigidity constraints KW - image displacement fields KW - Image motion analysis KW - Image segmentation KW - Image sequences KW - imaging surface KW - Laboratories KW - Layout KW - Motion estimation KW - Motion measurement KW - motion vectors KW - multiple views KW - normal flow fields KW - optical flow fields KW - regions KW - rigid motion KW - stereo disparity fields KW - Stereo vision KW - vectors KW - visual information recovery AB - Image displacement fields-optical flow fields, stereo disparity fields, normal flow fields-due to rigid motion possess a global geometric structure which is independent of the scene in view. Motion vectors of certain lengths and directions are constrained to lie on the imaging surface at particular loci whose location and form depends solely on the 3D motion parameters. If optical flow fields or stereo disparity fields are considered, then equal vectors are shown to lie on conic sections. Similarly, for normal motion fields, equal vectors lie within regions whose boundaries also constitute conics. By studying various properties of these curves and regions and their relationships, a characterization of the structure of rigid motion fields is given. The goal of this paper is to introduce a concept underlying the global structure of image displacement fields. This concept gives rise to various constraints that could form the basis of algorithms for the recovery of visual information from multiple views JA - , Fifth International Conference on Computer Vision, 1995. Proceedings PB - IEEE SN - 0-8186-7042-8 M3 - 10.1109/ICCV.1995.466779 ER - TY - CONF T1 - Global rigidity constraints in image displacement fields T2 - Proceedings of Fifth International Conference on Computer Vision, 1995 Y1 - 1995 A1 - Fermüller, Cornelia A1 - Aloimonos, J. KW - 3D motion parameters KW - algorithms KW - Automation KW - Computer science KW - Computer vision KW - conic sections KW - curves KW - equal vectors KW - Fluid flow measurement KW - global geometric structure KW - global rigidity constraints KW - image displacement fields KW - Image motion analysis KW - Image segmentation KW - Image sequences KW - imaging surface KW - Laboratories KW - Layout KW - Motion estimation KW - Motion measurement KW - motion vectors KW - multiple views KW - normal flow fields KW - optical flow fields KW - regions KW - rigid motion KW - stereo disparity fields KW - Stereo vision KW - vectors KW - visual information recovery AB - Image displacement fields-optical flow fields, stereo disparity fields, normal flow fields-due to rigid motion possess a global geometric structure which is independent of the scene in view. Motion vectors of certain lengths and directions are constrained to lie on the imaging surface at particular loci whose location and form depends solely on the 3D motion parameters. If optical flow fields or stereo disparity fields are considered, then equal vectors are shown to lie on conic sections. Similarly, for normal motion fields, equal vectors lie within regions whose boundaries also constitute conics. By studying various properties of these curves and regions and their relationships, a characterization of the structure of rigid motion fields is given. The goal of this paper is to introduce a concept underlying the global structure of image displacement fields. This concept gives rise to various constraints that could form the basis of algorithms for the recovery of visual information from multiple views JA - Proceedings of Fifth International Conference on Computer Vision, 1995 PB - IEEE SN - 0-8186-7042-8 M3 - 10.1109/ICCV.1995.466779 ER - TY - CONF T1 - The information in the direction of image flow T2 - , International Symposium on Computer Vision, 1995. Proceedings Y1 - 1995 A1 - Brodsky, T. A1 - Fermüller, Cornelia A1 - Aloimonos, J. KW - Automation KW - CAMERAS KW - Computer vision KW - Educational institutions KW - image flow KW - Image motion analysis KW - Image sequences KW - imaging surface KW - Laboratories KW - Layout KW - Motion analysis KW - Motion estimation KW - motion field KW - motion vectors KW - Optical imaging KW - rigid motion KW - rigid motions KW - three-dimensional motion AB - If instead of the full motion field, we consider only the direction of the motion field due to a rigid motion, what can we say about the information regarding the three-dimensional motion? In this paper it is shown that considering as the imaging surface the whole sphere, independently of the scene in view, two different rigid motions cannot give rise to the same directional motion field. If we restrict the image to half of a sphere (or an infinitely large image plane) two different rigid motions with instantaneous translational and rotational velocities (t1, ω1) and (t2, ω2) cannot give rise to the same directional motion field unless the plane through t1 and t2 is perpendicular to the plane through ω1 and ω2 (i.e., (t1×t2)·(ω1 ×ω2)=0). In addition, in order to give a practical significance to these uniqueness results for the case of a limited field of view we also characterize the locations on the image where the motion vectors due to the different motions must have different directions. If (ω1×ω2)·(t1 ×t2)=0 and certain additional constraints are met, then the two rigid motions could produce motion fields with the same direction. For this to happen the depth of each corresponding surface has to be within a certain range, defined by a second and a third order surface JA - , International Symposium on Computer Vision, 1995. Proceedings PB - IEEE SN - 0-8186-7190-4 M3 - 10.1109/ISCV.1995.477071 ER - TY - JOUR T1 - An integrated runtime and compile-time approach for parallelizing structured and block structured applications JF - IEEE Transactions on Parallel and Distributed Systems Y1 - 1995 A1 - Agrawal,G. A1 - Sussman, Alan A1 - Saltz, J. KW - Bandwidth KW - block structured applications KW - block structured codes KW - compile-time approach KW - compiling applications KW - data access patterns KW - Data analysis KW - Delay KW - distributed memory machines KW - distributed memory systems KW - FORTRAN KW - Fortran 90D/HPF compiler KW - High performance computing KW - HPF-like parallel programming languages KW - integrated runtime approach KW - irregularly coupled regular mesh problems KW - multigrid code KW - Navier-Stokes solver template KW - Parallel machines KW - parallel programming KW - Pattern analysis KW - performance evaluation KW - program compilers KW - Program processors KW - Runtime library KW - Uninterruptible power systems AB - In compiling applications for distributed memory machines, runtime analysis is required when data to be communicated cannot be determined at compile-time. One such class of applications requiring runtime analysis is block structured codes. These codes employ multiple structured meshes, which may be nested (for multigrid codes) and/or irregularly coupled (called multiblock or irregularly coupled regular mesh problems). In this paper, we present runtime and compile-time analysis for compiling such applications on distributed memory parallel machines in an efficient and machine-independent fashion. We have designed and implemented a runtime library which supports the runtime analysis required. The library is currently implemented on several different systems. We have also developed compiler analysis for determining data access patterns at compile time and inserting calls to the appropriate runtime routines. Our methods can be used by compilers for HPF-like parallel programming languages in compiling codes in which data distribution, loop bounds and/or strides are unknown at compile-time. To demonstrate the efficacy of our approach, we have implemented our compiler analysis in the Fortran 90D/HPF compiler developed at Syracuse University. We have experimented with a multi-bloc Navier-Stokes solver template and a multigrid code. Our experimental results show that our primitives have low runtime communication overheads and the compiler parallelized codes perform within 20% of the codes parallelized by manually inserting calls to the runtime library VL - 6 SN - 1045-9219 CP - 7 M3 - 10.1109/71.395403 ER - TY - CONF T1 - Iso-distortion contours and egomotion estimation T2 - Proceedings of International Symposium on Computer Vision, 1995 Y1 - 1995 A1 - LoongFah Cheong A1 - Aloimonos, J. KW - Automation KW - Computer vision KW - Degradation KW - depth distortion KW - Educational institutions KW - egomotion estimation KW - Equations KW - erroneous motion estimates KW - Error analysis KW - HUMANS KW - Image sequences KW - iso-distortion contours KW - Laboratories KW - Layout KW - Motion estimation KW - Robustness KW - visibility constraint AB - This paper introduces the framework of iso-distortion contour to deal with the problem of depth distortion due to erroneous motion estimates, and various related aspects such as the effectiveness of the visibility constraint. The framework can also be used to inquire the uniqueness aspect of normal flow. Future work will examine the implications of the iso-distortion contours for the problem of multiple frame integration JA - Proceedings of International Symposium on Computer Vision, 1995 PB - IEEE SN - 0-8186-7190-4 M3 - 10.1109/ISCV.1995.476977 ER - TY - CONF T1 - M.H.M: Euclidean spanners: short, thin, and lanky T2 - In: 27th ACM Symposium on Theory of Computing Y1 - 1995 A1 - Arya,Sunil A1 - Dast,Gautam A1 - Mount, Dave A1 - Salowe,Jeffrey S. A1 - Smid,Michiel AB - Euclidean spanners are important data structures in geometric algorithm design, because they provide a means of approximating the complete Euclidean graph with only O(n) edges, so that the shortest path length between each pair of points is not more than a constant factor longer than the Euclidean distance between the points. In many applications of spanners, it is important that the spanner possess a number of additional properties: low tot al edge weight, bounded degree, and low diameter. Existing research on spanners has considered one property or the other. We show that it is possible to build spanners in optimal O (n log n) time and O(n) space that achieve optimal or near optimal tradeoffs between all combinations of these *Max-Planck-Institut fiir Informatik, D-66123 Saarbrucken, JA - In: 27th ACM Symposium on Theory of Computing PB - ACM press ER - TY - JOUR T1 - Next generation network management technology JF - AIP Conference Proceedings Y1 - 1995 A1 - Baras,John S A1 - Atallah,George C A1 - Ball,Mike A1 - Goli,Shravan A1 - Karne,Ramesh K A1 - Kelley,Steve A1 - Kumar,Harsha A1 - Plaisant, Catherine A1 - Roussopoulos, Nick A1 - Schneiderman,Ben A1 - Srinivasarao,Mulugu A1 - Stathatos,Kosta A1 - Teittinen,Marko A1 - Whitefield,David AB - Today’s telecommunications networks are becoming increasingly large, complex, mission critical and heterogeneous in several dimensions. For example, the underlying physical transmission facilities of a given network may be ‘‘mixed media’’ (copper, fiber‐optic, radio, and satellite); the subnetworks may be acquired from different vendors due to economic, performance, or general availability reasons; the information being transmitted over the network may be ‘‘multimedia’’ (video, data, voice, and images) and, finally, varying performance criteria may be imposed e.g., data transfer may require high throughput while the others, whose concern is voice communications, may require low call blocking probability. For these reasons, future telecommunications networks are expected to be highly complex in their services and operations. Due to this growing complexity and the disparity among management systems for individual sub‐networks, efficient network management systems have become critical to the current and future success of telecommunications companies. This paper addresses a research and development effort which focuses on prototyping configuration management, since that is the central process of network management and all other network management functions must be built upon it. Our prototype incorporates ergonomically designed graphical user interfaces tailored to the network configuration management subsystem and to the proposed advanced object‐oriented database structure. The resulting design concept follows open standards such as Open Systems Interconnection (OSI) and incorporates object oriented programming methodology to associate data with functions, permit customization, and provide an open architecture environment. © 1995 American Institute of Physics VL - 325 SN - 0094243X UR - http://proceedings.aip.org/resource/2/apcpcs/325/1/75_1?isAuthorized=no CP - 1 M3 - doi:10.1063/1.47255 ER - TY - JOUR T1 - Qualitative egomotion JF - International Journal of Computer Vision Y1 - 1995 A1 - Fermüller, Cornelia A1 - Aloimonos, J. AB - Due to the aperture problem, the only motion measurement in images, whose computation does not require any assumptions about the scene in view, is normal flow—the projection of image motion on the gradient direction. In this paper we show how a monocular observer can estimate its 3D motion relative to the scene by using normal flow measurements in a global and qualitative way. The problem is addressed through a search technique. By checking constraints imposed by 3D motion parameters on the normal flow field, the possible space of solutions is gradually reduced. In the four modules that comprise the solution, constraints of increasing restriction are considered, culminating in testing every single normal flow value for its consistency with a set of motion parameters. The fact that motion is rigid defines geometric relations between certain values of the normal flow field. The selected values form patterns in the image plane that are dependent on only some of the motion parameters. These patterns, which are determined by the signs of the normal flow values, are searched for in order to find the axes of translation and rotation. The third rotational component is computed from normal flow vectors that are only due to rotational motion. Finally, by looking at the complete data set, all solutions that cannot give rise to the given normal flow field are discarded from the solution space. VL - 15 SN - 0920-5691 UR - http://dx.doi.org/10.1007/BF01450848 CP - 1 ER - TY - JOUR T1 - Qualitative vision JF - International Journal of Computer Vision Y1 - 1995 A1 - Aloimonos, J. VL - 14 CP - 2 ER - TY - CONF T1 - Representations for active vision T2 - Proceedings of the 14th international joint conference on Artificial intelligence - Volume 1 Y1 - 1995 A1 - Fermüller, Cornelia A1 - Aloimonos, J. JA - Proceedings of the 14th international joint conference on Artificial intelligence - Volume 1 PB - Morgan Kaufmann Publishers Inc. CY - San Francisco, CA, USA SN - 1-55860-363-8, 978-1-558-60363-9 UR - http://dl.acm.org/citation.cfm?id=1625855.1625858 ER - TY - JOUR T1 - Seeing and understanding: representing the visual world JF - ACM Comput. Surv. Y1 - 1995 A1 - Aloimonos, J. A1 - Fermüller, Cornelia A1 - Rosenfeld, A. VL - 27 SN - 0360-0300 UR - http://doi.acm.org/10.1145/212094.212101 CP - 3 M3 - 10.1145/212094.212101 ER - TY - JOUR T1 - Striving for correctness JF - Computers & Security Y1 - 1995 A1 - Abrams,Marshall D. A1 - Zelkowitz, Marvin V KW - Assurance KW - belief KW - correctness KW - Formal Methods KW - MATHEMATICAL MODELS KW - metrics KW - Process models KW - Risk management KW - Security testing KW - Silver bullets KW - simulation KW - Trustworthiness AB - In developing information technology, you want assurance that systems are secure and reliable, but you cannot have assurance or security without correctness. We discuss methods used to achieve correctness, focusing on weaknesses and approaches that management might take to increase belief in correctness. Formal methods, simulation, testing, and process modeling are addressed in detail. Structured programming, life-cycle modeling like the spiral model, use of CASE tools, use of formal methods, object-oriented design, reuse of existing code are also mentioned. Reliance on these methods involves some element of belief since no validated metrics on the effectiveness of these methods exist. Suggestions for using these methods as the basis for managerial decisions conclude the paper. VL - 14 SN - 0167-4048 UR - http://www.sciencedirect.com/science/article/pii/0167404895000224 CP - 8 M3 - 10.1016/0167-4048(95)00022-4 ER - TY - JOUR T1 - Using Treemaps to Visualize the Analytic Hierarchy Process JF - Information Systems ResearchInformation Systems Research Y1 - 1995 A1 - Asahi,Toshiyuki A1 - Turo,David A1 - Shneiderman, Ben KW - AHP KW - analytic hierarchy process KW - decision support KW - treemap KW - User interfaces KW - Visualization AB - Treemaps, a visualization method for large hierarchical data spaces, are used to augment the capabilities of the Analytic Hierarchy Process (AHP) for decision-making. Two direct manipulation tools, presented metaphorically as a “pump” and a “hook,” were developed and applied to the treemap to support AHP sensitivity analysis. Users can change the importance of criteria dynamically on the two-dimensional treemap and immediately see the impact on the outcome of the decision. This fluid process dramatically speeds up exploration and provides a better understanding of the relative impact of the component criteria. A usability study with six subjects using a prototype AHP application showed that treemap representation was acceptable from a visualization and data operation standpoint. VL - 6 SN - 1047-7047, 1526-5536 UR - http://isr.journal.informs.org/content/6/4/357 CP - 4 M3 - 10.1287/isre.6.4.357 ER - TY - JOUR T1 - Vision and action JF - Image and Vision Computing Y1 - 1995 A1 - Fermüller, Cornelia A1 - Aloimonos, J. KW - active vision KW - perceptual system design and analysis KW - vision system architecture AB - Our work on active vision has recently focused on the computational modelling of navigational tasks, where our investigations were guided by the idea of approaching vision for behavioural systems in the form of modules that are directly related to perceptual tasks. These studies led us to branch in various directions and inquire into the problems that have to be addressed in order to obtain an overall understanding of perceptual systems. In this paper, we present our views about the architecture of vision systems, about how to tackle the design and analysis of perceptual systems, and promising future research directions. Our suggested approach for understanding behavioural vision to realize the relationships of perception and action builds on two earlier approaches, the Medusa philosophy1 and the Synthetic approach2. The resulting framework calls for synthesizing an artificial vision system by studying vision competences of increasing complexity and, at the same time, pursuing the integration of the perceptual components with action and learning modules. We expect that computer vision research in the future will progress in tight collaboration with many other disciplines that are concerned with empirical approaches to vision, i.e. the understanding of biological vision. Throughout the paper, we describe biological findings that motivate computational arguments which we believe will influence studies of computer vision in the near future. VL - 13 SN - 0262-8856 UR - http://www.sciencedirect.com/science/article/pii/026288569598754H CP - 10 M3 - 10.1016/0262-8856(95)98754-H ER - TY - JOUR T1 - Vision and action* 1 JF - Image and vision computing Y1 - 1995 A1 - Fermüller, Cornelia A1 - Aloimonos, J. VL - 13 CP - 10 ER - TY - JOUR T1 - Vision, Graphic Design, and Visual Display JF - Readings in human-computer interaction: toward the year 2000 Y1 - 1995 A1 - Marcus,A. A1 - Murch,G.M. A1 - Baecker,R. A1 - Small,I. A1 - Mander,R. A1 - Ahlberg,C. A1 - Shneiderman, Ben ER - TY - CONF T1 - Visual decision-making: using treemaps for the analytic hierarchy process T2 - Conference companion on Human factors in computing systems Y1 - 1995 A1 - Asahi,Toshiyuki A1 - Turo,David A1 - Shneiderman, Ben JA - Conference companion on Human factors in computing systems T3 - CHI '95 PB - ACM CY - New York, NY, USA SN - 0-89791-755-3 UR - http://doi.acm.org/10.1145/223355.223747 M3 - 10.1145/223355.223747 ER - TY - JOUR T1 - Windows of opportunity in electronic classrooms JF - Communications of the ACM Y1 - 1995 A1 - Shneiderman, Ben A1 - Alavi,Maryann A1 - Norman,Kent A1 - Borkowski,Ellen Yu AB - Paradigm-shifting landmark buildings are cherished by their occupants and remembered because they reshape our expectations of schools, homes, or offices. Classic examples include Thomas Jefferson's communal design of the “academical village” at the University of Virginia where faculty and students lived close to classrooms, Frank Lloyd Wright's organic harmony with nature in Fallingwater (in western Pennsylvania) where the waterfall sounds and leafy surroundings offered a stress-reducing getaway for an urban executive, or Kevin Roche's open glass-walled Ford Foundation (in New York City) that promoted new team-oriented management strategies. VL - 38 SN - 0001-0782 UR - http://doi.acm.org/10.1145/219717.219725 CP - 11 M3 - 10.1145/219717.219725 ER - TY - CONF T1 - The alphaslider: a compact and rapid selector T2 - Proceedings of the SIGCHI conference on Human factors in computing systems: celebrating interdependence Y1 - 1994 A1 - Ahlberg,Christopher A1 - Shneiderman, Ben KW - Alphaslider KW - dynamic queries KW - menus KW - selection technology KW - widget JA - Proceedings of the SIGCHI conference on Human factors in computing systems: celebrating interdependence T3 - CHI '94 PB - ACM CY - New York, NY, USA SN - 0-89791-650-6 UR - http://doi.acm.org/10.1145/191666.191790 M3 - 10.1145/191666.191790 ER - TY - JOUR T1 - Cortical map reorganization as a competitive process JF - Neural Computation Y1 - 1994 A1 - Sutton III,G. G. A1 - Reggia, James A. A1 - Armentrout,S. L A1 - D'Autrechy,C. L VL - 6 CP - 1 ER - TY - JOUR T1 - Design and implementation of Maruti-II JF - Principles of Real-Time Systems. Prentice Hall Y1 - 1994 A1 - Saksena,M. A1 - da Silva,J. A1 - Agrawala, Ashok K. ER - TY - JOUR T1 - Dynamic algorithms for geometric spanners of small diameter: Randomized solutions JF - Computational Geometry: Theory and Applications Y1 - 1994 A1 - Arya,Sunil A1 - Mount, Dave A1 - Smid,Michiel AB - Let S be a set of n points in IR d and let t ? 1 be a real number. A t-spanner for S is a directed graph having the points of S as its vertices, such that for any pair p and q of points there is a path from p to q of length at most t times the Euclidean distance between p and q. Such a path is called a t-spanner path. The spanner diameter of such a spanner is defined as the smallest integer D such that for any pair p and q of points there is a t-spanner path from p to q containing at most D edges. A randomized algorithm is given for constructing a t-spanner that, with high probability, contains O(n) edges and has spanner diameter O(log n). A data structure of size O(n log d n) is given that maintains this t-spanner in O(log d n log log n) expected amortized time per insertion and deletion, in the model of random updates, as introduced by Mulmuley. Keywords: Computational geometry, proximity problems, skip lists, randomization, dynamic data structures. Preprint submitted to Els... VL - 13 ER - TY - CONF T1 - Efficient runtime support for parallelizing block structured applications T2 - Scalable High-Performance Computing Conference, 1994., Proceedings of the Y1 - 1994 A1 - Agrawal,G. A1 - Sussman, Alan A1 - Saltz, J. KW - application programmers KW - block structured applications KW - distributed memory parallel machines KW - distributed memory systems KW - engineering applications KW - irregularly coupled regular mesh problems KW - machine-independent KW - multiblock KW - multiblock computational fluid dynamics code KW - multiblock template KW - multigrid codes KW - Parallel machines KW - parallel programming KW - Physics computing KW - runtime communication overhead KW - Runtime library KW - runtime support KW - scientific applications KW - software reusability KW - structured meshes AB - Scientific and engineering applications often involve structured meshes. These meshes may be nested (for multigrid codes) and/or irregularly coupled (called multiblock or irregularly coupled regular mesh problems). We describe a runtime library for parallelizing these applications on distributed memory parallel machines in an efficient and machine-independent fashion. This runtime library is implemented on several different systems. This library can be used by application programmers to port applications by hand and can also be used by a compiler to handle communication for these applications. Our experimental results show that our primitives have low runtime communication overheads. We have used this library to port a multiblock template and a multigrid code. Effort is also underway to port a complete multiblock computational fluid dynamics code using our library JA - Scalable High-Performance Computing Conference, 1994., Proceedings of the M3 - 10.1109/SHPCC.1994.296639 ER - TY - JOUR T1 - Error propagation in 3D-from-2D recognition: Scaled-orthographic and perspective projections JF - Proceedings: ARPA Image Understanding Workshop, Monterey, California Y1 - 1994 A1 - Alter,T. D. A1 - Jacobs, David W. AB - Robust recognition systems require a careful under-standing of the e ects of error in sensed features. Error in these image features results in uncertainty in the possible image location of each additional model feature. We present an accurate, analytic ap- proximation for this uncertainty when model poses are based on matching three image and model points. This result applies to objects that are fully three- dimensional, where past results considered only two- dimensional objects. Further, we introduce a lin- ear programming algorithm to compute this uncer- tainty when poses are based on any number of initial matches. ER - TY - CONF T1 - Error propagation in full 3D-from-2D object recognition T2 - Computer Vision and Pattern Recognition, 1994. Proceedings CVPR '94., 1994 IEEE Computer Society Conference on Y1 - 1994 A1 - Alter,T. D. A1 - Jacobs, David W. KW - 3D-from-2D KW - algorithm; KW - error KW - extraction; KW - feature KW - features; KW - handling; KW - image KW - initial KW - linear KW - matches; KW - object KW - Programming KW - programming; KW - propagation; KW - recognition KW - recognition; KW - robust KW - sequences; KW - systems; KW - Uncertainty KW - uncertainty; AB - Robust recognition systems require a careful understanding of the effects of error in sensed features. Error in these image features results in uncertainty in the possible image location of each additional model feature. We present an accurate, analytic approximation for this uncertainty when model poses are based on matching three image and model points. This result applies to objects that are fully three-dimensional, where past results considered only two-dimensional objects. Further, we introduce a linear programming algorithm to compute this uncertainty when poses are based on any number of initial matches JA - Computer Vision and Pattern Recognition, 1994. Proceedings CVPR '94., 1994 IEEE Computer Society Conference on M3 - 10.1109/CVPR.1994.323920 ER - TY - JOUR T1 - Estimating the heading direction using normal flow JF - International Journal of Computer Vision Y1 - 1994 A1 - Aloimonos, J. A1 - Duric, Z. VL - 13 CP - 1 ER - TY - BOOK T1 - Fault tolerant system design Y1 - 1994 A1 - Levi,Shem-Tov A1 - Agrawala, Ashok K. KW - Computers / Intelligence (AI) & Semantics KW - Computers / Programming Languages / General KW - Computers / Software Development & Engineering / Systems Analysis & Design KW - Reference / General KW - Technology & Engineering / Engineering (General) AB - This book presents a comprehensive exploration of the practical issues, tested techniques, and accepted theory for developing fault tolerant systems. It is a ready reference to work already done in the field, with new approaches devised by the authors. PB - McGraw-Hill SN - 9780070375154 ER - TY - JOUR T1 - How normal flow constrains relative depth for an active observer JF - Image and vision computing Y1 - 1994 A1 - Huang, L. A1 - Aloimonos, J. VL - 12 CP - 7 ER - TY - CONF T1 - Integrated approaches for improving the effectiveness of Plan Reuse (A Progress Report) T2 - ARPA/Rome Laboratory knowledge-based planning and scheduling initiative: workshop proceedings: Tuscon, Arizona, February 21-24, 1994 Y1 - 1994 A1 - Kambhampati,S. A1 - Ihrig,L. A1 - Katukam,S. A1 - Chen,J. A1 - Hendler,J. A A1 - Agrawala, Ashok K. JA - ARPA/Rome Laboratory knowledge-based planning and scheduling initiative: workshop proceedings: Tuscon, Arizona, February 21-24, 1994 ER - TY - JOUR T1 - Mission-oriented replication of periodic tasks in real-time distributed systems JF - Computer Science Technical Report Series; Vol. CS-TR-3256 Y1 - 1994 A1 - Cheng,S. T A1 - Hwang,S. I A1 - Agrawala, Ashok K. ER - TY - JOUR T1 - A neural model of cortical map reorganization following a focal lesion JF - Artificial Intelligence in Medicine Y1 - 1994 A1 - Armentrout,S. L A1 - Reggia, James A. A1 - Weinrich,M. VL - 6 CP - 5 ER - TY - RPRT T1 - Next Generation Network Management Technology Y1 - 1994 A1 - Atallah,George C A1 - Ball,Michael O A1 - Baras,John S A1 - Goli,Shravan K A1 - Karne,Ramesh K A1 - Kelley,Stephen A1 - Kumar,Harsha P. A1 - Plaisant, Catherine A1 - Roussopoulos, Nick A1 - Shneiderman, Ben A1 - Srinivasarao,Mulugu A1 - Stathatos,Kostas A1 - Teittinen,Marko A1 - Whitefield,David KW - Constraints for Network Management. KW - Network Configuration Management KW - network management KW - Object Oriented Data Base Model for Network Management KW - Rules KW - Systems Integration KW - Visual Information Management for Network Configuration Management AB - Today's telecommunications networks are becoming increasingly large, complex, mission critical and heterogeneous in several dimensions. For example, the underlying physical transmission facilities of a given network may be ﲭixed media (copper, fiber- optic, radio, and satellite); the sub networks may be acquired from different vendors due to economic, performance, or general availability reasons; the information being transmitted over the network may be ﲭultimedia (video, data, voice, and images) and, finally, varying performance criteria may be imposed e.g. data transfer may require high throughput while the others, whose concern is voice communications, may require low call blocking probability. For these reasons, future telecommunications networks are expected to be highly complex in their services and operations. Due to this growing complexity and the disparity among management systems for individual sub networks, efficient network management systems have become critical to the current and future success of telecommunications companies. This paper addresses a research and development effort which focuses on prototyping configuration management, since that is the central process of network management and all other network management functions must be built upon it. Our prototype incorporates ergonomically designed graphical user interfaces tailored to the network configuration management subsystem and to the proposed advanced object-oriented database structure. The resulting design concept follows open standards such as Open Systems Interconnection (OSI) and incorporates object oriented programming methodology to associate data with functions, permit customization, and provide an open architecture environment. JA - Institute for Systems Research Technical Reports UR - http://drum.lib.umd.edu/handle/1903/5519 ER - TY - CONF T1 - Principles of computer vision T2 - Handbook of pattern recognition and image processing (vol. 2) Y1 - 1994 A1 - Aloimonos, J. A1 - Rosenfeld, A. JA - Handbook of pattern recognition and image processing (vol. 2) ER - TY - CONF T1 - Randomized and deterministic algorithms for geometric spanners of small diameter T2 - Foundations of Computer Science, 1994 Proceedings., 35th Annual Symposium on Y1 - 1994 A1 - Arya,S. A1 - Mount, Dave A1 - Smid,M. KW - computational geometry KW - deletions KW - deterministic algorithms KW - directed graph KW - directed graphs KW - geometric spanners KW - insertions KW - randomised algorithms KW - randomized algorithms AB - Let S be a set of n points in IRd and let t gt;1 be a real number. A t-spanner for S is a directed graph having the points of S as its vertices, such that for any pair p and q of points there is a path from p to q of length at most t times the Euclidean distance between p and p. Such a path is called a t-spanner path. The spanner diameter of such a spanner is defined as the smallest integer D such that for any pair p and q of points there is a t-spanner path from p to q containing at most D edges. Randomized and deterministic algorithms are given for constructing t-spanners consisting of O(n) edges and having O(log n) diameter. Also, it is shown how to maintain the randomized t-spanner under random insertions and deletions. Previously, no results were known for spanners with low spanner diameter and for maintaining spanners under insertions and deletions JA - Foundations of Computer Science, 1994 Proceedings., 35th Annual Symposium on M3 - 10.1109/SFCS.1994.365722 ER - TY - RPRT T1 - Uncertainty Propagation in Model-Based Recognition. Y1 - 1994 A1 - Jacobs, David W. A1 - Alter,T. D. KW - *IMAGE PROCESSING KW - *PATTERN RECOGNITION KW - algorithms KW - APPROXIMATION(MATHEMATICS) KW - CYBERNETICS KW - ERROR CORRECTION CODES KW - image registration KW - Linear programming KW - MATCHING KW - MATHEMATICAL MODELS KW - PIXELS KW - PROJECTIVE TECHNIQUES. KW - regions KW - THREE DIMENSIONAL KW - TWO DIMENSIONAL KW - Uncertainty AB - Building robust recognition systems requires a careful understanding of the effects of error in sensed features. Error in these image features results in a region of uncertainty in the possible image location of each additional model feature. We present an accurate, analytic approximation for this uncertainty region when model poses are based on matching three image and model points, for both Gaussian and bounded error in the detection of image points, and for both scaled-orthographic and perspective projection models. This result applies to objects that are fully three-dimensional, where past results considered only two-dimensional objects. Further, we introduce a linear programming algorithm to compute the uncertainty region when poses are based on any number of initial matches. Finally, we use these results to extend, from two-dimensional to three-dimensional objects, robust implementations of alignment interpretation-tree search, and transformation clustering. (AN) PB - MASSACHUSETTS INSTITUTE OF TECHNOLOGY ARTIFICIAL INTELLIGENCE LAB UR - http://stinet.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA295642 ER - TY - CONF T1 - Visual information seeking: tight coupling of dynamic query filters with starfield displays T2 - Proceedings of the SIGCHI conference on Human factors in computing systems: celebrating interdependence Y1 - 1994 A1 - Ahlberg,Christopher A1 - Shneiderman, Ben KW - database query KW - dynamic queries KW - information seeking KW - starfield displays KW - tight coupling JA - Proceedings of the SIGCHI conference on Human factors in computing systems: celebrating interdependence T3 - CHI '94 PB - ACM CY - New York, NY, USA SN - 0-89791-650-6 UR - http://doi.acm.org/10.1145/191666.191775 M3 - 10.1145/191666.191775 ER - TY - JOUR T1 - Visual information seeking using the FilmFinder JF - ACM CHI94 Conference, Boston Y1 - 1994 A1 - Ahlberg,C. A1 - Shneiderman, Ben ER - TY - JOUR T1 - What I have learned JF - CVGIP: Image Understanding Y1 - 1994 A1 - Aloimonos, J. VL - 60 CP - 1 ER - TY - BOOK T1 - Active perception. Y1 - 1993 A1 - Aloimonos, J. PB - Lawrence Erlbaum Associates, Inc ER - TY - BOOK T1 - Active Perception, Vol. I of Advances in Computer Vision series Y1 - 1993 A1 - Aloimonos, J. PB - Lawrence Erlbaum Associates ER - TY - JOUR T1 - Active vision revisited JF - Active Perception Y1 - 1993 A1 - Aloimonos, J. ER - TY - CONF T1 - Algorithms for fast vector quantization T2 - Data Compression Conference, 1993. DCC '93. Y1 - 1993 A1 - Arya,S. A1 - Mount, Dave KW - algorithm; KW - algorithms; KW - directed KW - fast KW - graph KW - graph; KW - graphs; KW - Neighborhood KW - performance; KW - problems; KW - quantisation; KW - quantization; KW - running KW - search KW - time; KW - tree KW - vector AB - This paper shows that if one is willing to relax the requirement of finding the true nearest neighbor, it is possible to achieve significant improvements in running time and at only a very small loss in the performance of the vector quantizer. The authors present three algorithms for nearest neighbor searching: standard and priority k -d tree search algorithms and a neighborhood graph search algorithm in which a directed graph is constructed for the point set and edges join neighboring points JA - Data Compression Conference, 1993. DCC '93. M3 - 10.1109/DCC.1993.253111 ER - TY - CONF T1 - Approximate nearest neighbor queries in fixed dimensions T2 - Proceedings of the fourth annual ACM-SIAM Symposium on Discrete algorithms Y1 - 1993 A1 - Arya,Sunil A1 - Mount, Dave JA - Proceedings of the fourth annual ACM-SIAM Symposium on Discrete algorithms T3 - SODA '93 PB - Society for Industrial and Applied Mathematics CY - Philadelphia, PA, USA SN - 0-89871-313-7 UR - http://dl.acm.org/citation.cfm?id=313559.313768 ER - TY - JOUR T1 - Approximate nearest neighbor searching JF - Proceedings of 4th Annual ACMSIAM Symposium on Discrete Algorithms (SODA’93) Y1 - 1993 A1 - Arya,S. A1 - Mount, Dave ER - TY - CONF T1 - Fast search algorithms with applications to split and multi-stage vector quantization of speech lsp parameters T2 - Speech Coding for Telecommunications, 1993. Proceedings., IEEE Workshop on Y1 - 1993 A1 - Arya,S. A1 - Phamdo,N. A1 - Farvardin,N. A1 - Mount, Dave JA - Speech Coding for Telecommunications, 1993. Proceedings., IEEE Workshop on M3 - 10.1109/SCFT.1993.762341 ER - TY - JOUR T1 - Geometric knapsack problems JF - Algorithmica Y1 - 1993 A1 - Arkin,E. M A1 - Khuller, Samir A1 - Mitchell,J. S.B AB - We study a variety of geometric versions of the classical knapsack problem. In particular, we consider the following ldquofence enclosurerdquo problem: given a setS ofn points in the plane with valuesv i ge 0, we wish to enclose a subset of the points with a fence (a simple closed curve) in order to maximize the ldquovaluerdquo of the enclosure. The value of the enclosure is defined to be the sum of the values of the enclosed points minus the cost of the fence. We consider various versions of the problem, such as allowingS to consist of points and/or simple polygons. Other versions of the problems are obtained by restricting the total amount of fence available and also allowing the enclosure to consist of at mostM connected components. When there is an upper bound on the length of fence available, we show that the problem is NP-complete. We also provide polynomial-time algorithms for many versions of the fence problem when an unrestricted amount of fence is available. VL - 10 CP - 5 M3 - 10.1007/BF01769706 ER - TY - CONF T1 - Multiple Resource Allocation for Multiprocessor Distributed Real-Time Systems T2 - In Workshop on Parallel and Distributed Real-Time Systems (PDRTS), IEEE IPPS'93 Y1 - 1993 A1 - Mosse,Daniel A1 - Noh,Sam H A1 - Trinh,Bao A1 - Agrawala, Ashok K. AB - this report are those of the author(s) and should not be interpreted as representing the official policies, either expressed or implied, of the Defense Advanced Research Projects Agency, ONR, the U.S. Government or Honeywell. Computer facilities were provided in part by NSF grant CCR-8811954. Workshop on Parallel and Dist Real-Time Syst, IEEE IPPS'93 April 1993 in the queue and tries to schedule it. If the task is successfully scheduled, it is removed from the queue and executed. Otherwise, the task is unlocked so that other processors may examine it in the same fashion. This scheme is convenient for a shared memory architecture, but becomes too expensive and cumbersome when such facility is not available in hardware (for example, in distributed systems). The goal of this paper is twofold: first, to study the problem of allocating multiple resources to a single task; and second, to provide a heuristic allocation policy for selecting a resource among multiple instances of identical resources. We consider a distributed system in which each site is a uniform memory access (UMA) multiprocessor, but the scheme is easily extensible to non-UMA models. For the first problem, a three-tiered resource allocation scheme is proposed. A hierarchy of the resources is defined to reduce the probability of allocation failure as the allocation progresses. To reduce the complexity of multiple resource allocation, we group the resources into schedulable sets of resources. Since the objective in real-time systems is to meet deadlines, this approach is acceptable so long as it meets a justifiable minimum level of resource utilization. It is shown that our approach allows modularity, flexibility, and potential concurrency in scheduling. Another contribution of this paper is in explicitly ide... JA - In Workshop on Parallel and Distributed Real-Time Systems (PDRTS), IEEE IPPS'93 ER - TY - JOUR T1 - Point probe decision trees for geometric concept classes JF - Algorithms and Data Structures Y1 - 1993 A1 - Arkin,E. A1 - Goodrich,M. A1 - Mitchell,J. A1 - Mount, Dave A1 - Piatko,C. A1 - Skiena,S. AB - A fundamental problem in model-based computer vision is that of identifying to which of a given set of concept classes of geometric models an observed model belongs. Considering a ldquoproberdquo to be an oracle that tells whether or not the observed model is present at a given point in an image, we study the problem of computing efficient strategies (ldquodecision treesrdquo) for probing an image, with the goal to minimize the number of probes necessary (in the worst case) to determine in which class the observed model belongs. We prove a hardness result and give strategies that obtain decision trees whose height is within a log factor of optimal.These results grew out of discussions that began in a series of workshops on Geometric Probing in Computer Vision, sponsored by the Center for Night Vision and Electro-Optics, Fort Belvoir, Virginia, and monitored by the U.S. Army Research Office. The views, opinions, and/or findings contained in this report are those of the authors and should not be construed as an official Department of the Army position, policy, or decision, unless so designated by other documentation. M3 - 10.1007/3-540-57155-8_239 ER - TY - JOUR T1 - Probabilistic analysis of some navigation strategies in a dynamic environment JF - Systems, Man and Cybernetics, IEEE Transactions on Y1 - 1993 A1 - Sharma, R. A1 - Mount, Dave A1 - Aloimonos, J. VL - 23 CP - 5 ER - TY - JOUR T1 - Recognizing 3-D Motion JF - INTERNATIONAL JOINT CONFERENCE ON ARTIFICIAL IN℡LIGENCE Y1 - 1993 A1 - Fermüller, Cornelia A1 - Aloimonos, J. VL - 13 ER - TY - JOUR T1 - The role of fixation in visual motion analysis JF - International Journal of Computer Vision Y1 - 1993 A1 - Fermüller, Cornelia A1 - Aloimonos, J. AB - How does the ability of humans and primates to fixate at environmental points in the presence of relative motion help their visual systems in solving various tasks? To state the question in a more formal setting, we investigate in this article the following problem: Suppose that we have an active vision system, that is, a camera resting on a platform and being controlled through motors by a computer that has access to the images sensed by the camera in real time. The platform can move freely in the environment. If this machine can fixate on targets being in relative motion with it, can it solve visual tasks in an efficient and robust manner? By restricting our attention to a set of navigational tasks, we find that such an active observer can solve the problems of 3-D motion estimation, egomotion recovery, and estimation of time-to-contact in a very efficient manner, using as input the spatiotemporal derivatives of the image-intensity function (or normal flow). Fixation over time changes the input (motion field) in a controlled way and from this change additional information is derived making the previously mentioned tasks easier to solve. VL - 11 SN - 0920-5691 UR - http://dx.doi.org/10.1007/BF01469227 CP - 2 ER - TY - JOUR T1 - Simple systems that exhibit template-directed replication JF - Science Y1 - 1993 A1 - Reggia, James A. A1 - Armentrout,S. L A1 - Chou,H. H. A1 - Peng,Y. VL - 259 ER - TY - CONF T1 - Active egomotion estimation: a qualitative approach T2 - Computer Vision—ECCV'92 Y1 - 1992 A1 - Aloimonos, J. A1 - Duric, Z. JA - Computer Vision—ECCV'92 ER - TY - JOUR T1 - Behavioral Visual Motion Analysis," JF - Proceedings, DARPA Image Understanding Workshop Y1 - 1992 A1 - Aloimonos, J. A1 - Duriç,Z. A1 - Fermüller, Cornelia A1 - Huang, L. A1 - Rivlin,E. A1 - Sharma, R. ER - TY - JOUR T1 - Coordinated motion planning: the warehouseman's problem with constraints on free space JF - Systems, Man and Cybernetics, IEEE Transactions on Y1 - 1992 A1 - Sharma, R. A1 - Aloimonos, J. VL - 22 CP - 1 ER - TY - JOUR T1 - copia-like retrotransposons are ubiquitous among plants JF - Proc Natl Acad Sci USA Y1 - 1992 A1 - Voytas,D. F A1 - Cummings, Michael P. A1 - Koniczny,A. A1 - Ausubel,F. M A1 - Rodermel,S. R AB - Transposable genetic elements are assumed to be a feature of all eukaryotic genomes. Their identification, however, has largely been haphazard, limited principally to organisms subjected to molecular or genetic scrutiny. We assessed the phylogenetic distribution of copia-like retrotransposons, a class of transposable element that proliferates by reverse transcription, using a polymerase chain reaction assay designed to detect copia-like element reverse transcriptase sequences. copia-like retrotransposons were identified in 64 plant species as well as the photosynthetic protist Volvox carteri. The plant species included representatives from 9 of 10 plant divisions, including bryophytes, lycopods, ferns, gymnosperms, and angiosperms. DNA sequence analysis of 29 cloned PCR products and of a maize retrotransposon cDNA confirmed the identity of these sequences as copia-like reverse transcriptase sequences, thereby demonstrating that this class of retrotransposons is a ubiquitous component of plant genomes. VL - 89 CP - 15 ER - TY - CONF T1 - Dynamic queries: database searching by direct manipulation T2 - Proceedings of the SIGCHI conference on Human factors in computing systems Y1 - 1992 A1 - Shneiderman, Ben A1 - Williamson,Christopher A1 - Ahlberg,Christopher JA - Proceedings of the SIGCHI conference on Human factors in computing systems T3 - CHI '92 PB - ACM CY - New York, NY, USA SN - 0-89791-513-5 UR - http://doi.acm.org/10.1145/142750.143082 M3 - 10.1145/142750.143082 ER - TY - CONF T1 - Dynamic queries for information exploration: an implementation and evaluation T2 - Proceedings of the SIGCHI conference on Human factors in computing systems Y1 - 1992 A1 - Ahlberg,Christopher A1 - Williamson,Christopher A1 - Shneiderman, Ben AB - We designed, implemented and evaluated a new concept for direct manipulation of databases, called dynamic queries, that allows users to formulate queries with graphical widgets, such as sliders. By providing a graphical visualization of the database and search results, users can find trends and exceptions easily. Eighteen undergraduate chemistry students performed statistically significantly faster using a dynamic queries interface compared to two interfaces both providing form fill-in as input method, one with graphical visualization output and one with all-textual output. The interfaces were used to explore the periodic table of elements and search on their properties. JA - Proceedings of the SIGCHI conference on Human factors in computing systems T3 - CHI '92 PB - ACM CY - New York, NY, USA SN - 0-89791-513-5 UR - http://doi.acm.org/10.1145/142750.143054 M3 - 10.1145/142750.143054 ER - TY - CONF T1 - Efficient minimum cost matching using quadrangle inequality T2 - Foundations of Computer Science, 1992. Proceedings., 33rd Annual Symposium on Y1 - 1992 A1 - Aggarwal,A. A1 - Bar-Noy,A. A1 - Khuller, Samir A1 - Kravets,D. A1 - Schieber,B. KW - algorithm; KW - array; KW - bipartite KW - bitonic KW - blue KW - complexity; KW - computational KW - cost KW - distance; KW - Euclidean KW - function; KW - geometry; KW - graph KW - graphs; KW - inequality; KW - linear KW - MATCHING KW - matching; KW - minimisation; KW - minimum KW - Monge KW - perfect KW - points; KW - polynomial KW - problem; KW - quadrangle KW - red KW - theory; KW - TIME KW - transportation KW - transportation; KW - weakly AB - The authors present efficient algorithms for finding a minimum cost perfect matching, and for solving the transportation problem in bipartite graphs, G = (Red cup; Blue, Red times; Blue), where |Red| = n, |Blue| = m, n les; m, and the cost function obeys the quadrangle inequality. The first results assume that all the red points and all the blue points lie on a curve that is homeomorphic to either a line or a circle and the cost function is given by the Euclidean distance along the curve. They present a linear time algorithm for the matching problem. They generalize the method to solve the corresponding transportation problem in O((m+n)log(m+n)) time. The next result is an O(n log m) algorithm for minimum cost matching when the cost array is a bitonic Monge array. An example of this is when the red points lie on one straight line and the blue points lie on another straight line (that is not necessarily parallel to the first one). Finally, they provide a weakly polynomial algorithm for the transportation problem in which the associated cost array is a bitonic Monge array JA - Foundations of Computer Science, 1992. Proceedings., 33rd Annual Symposium on M3 - 10.1109/SFCS.1992.267793 ER - TY - JOUR T1 - Efficient pattern matching with scaling JF - Journal of Algorithms Y1 - 1992 A1 - Amir, A. A1 - Landau,G. M A1 - Vishkin, Uzi VL - 13 CP - 1 ER - TY - CONF T1 - Exploratory active vision: theory T2 - Proceedings of 1992 IEEE Computer Society Conference on Computer Vision and Pattern Recognition, 1992 Y1 - 1992 A1 - Herve,J. -Y A1 - Aloimonos, J. KW - active observer KW - Active shape model KW - active vision KW - Automation KW - autonomous robot KW - CAMERAS KW - Computer science KW - Computer vision KW - depth information KW - Laboratories KW - Layout KW - Mobile robots KW - Motion analysis KW - optical flow KW - Robots KW - shape from shading KW - shape from texture KW - shape from x modules KW - trajectory module KW - Visual system AB - An active approach to the integration of shape from x modules-here shape from shading and shape from texture-is proposed. The question of what constitutes a good motion for the active observer is addressed. Generally, the role of the visual system is to provide depth information to an autonomous robot; a trajectory module will then interpret it to determine a motion for the robot, which in turn will affect the visual information received. It is suggested that the motion can also be chosen so as to improve the performance of the visual system JA - Proceedings of 1992 IEEE Computer Society Conference on Computer Vision and Pattern Recognition, 1992 PB - IEEE SN - 0-8186-2855-3 M3 - 10.1109/CVPR.1992.223234 ER - TY - CONF T1 - Perceptual computational advantages of tracking T2 - , 11th IAPR International Conference on Pattern Recognition, 1992. Vol.I. Conference A: Computer Vision and Applications, Proceedings Y1 - 1992 A1 - Fermüller, Cornelia A1 - Aloimonos, J. KW - active vision KW - Automation KW - Employment KW - fixation KW - image intensity function KW - Image motion analysis KW - IMAGE PROCESSING KW - Motion estimation KW - Nonlinear optics KW - Optical computing KW - Optical sensors KW - parameter estimation KW - pattern recognition KW - perceptual computational advantages KW - spatiotemporal derivatives KW - Spatiotemporal phenomena KW - tracking KW - unrestricted motion KW - visual flow measurements AB - The paradigm of active vision advocates studying visual problems in the form of modules that are directly related to a visual task for observers that are active. It is argued that in many cases when an object is moving in an unrestricted manner (translation and rotation) in the 3D world only the motion's translational components are of interest. For a monocular observer, using only the normal flow-the spatiotemporal derivatives of the image intensity function-the authors solve the problem of computing the direction of translation. Their strategy uses fixation and tracking. Fixation simplifies much of the computation by placing the object at the center of the visual field, and the main advantage of tracking is the accumulation of information over time. The authors show how tracking is accomplished using normal flow measurements and use it for two different tasks in the solution process. First, it serves as a tool to compensate for the lack of existence of an optical flow field and thus to estimate the translation parallel to the image plane; and second, it gathers information about the motion component perpendicular to the image plane JA - , 11th IAPR International Conference on Pattern Recognition, 1992. Vol.I. Conference A: Computer Vision and Applications, Proceedings PB - IEEE SN - 0-8186-2910-X M3 - 10.1109/ICPR.1992.201633 ER - TY - RPRT T1 - Simple systems exhibiting self-directed replication: annex of transition functions and software documentation Y1 - 1992 A1 - Reggia, James A. A1 - Chou,Hui-Hsien A1 - Armentrout,Steven L. A1 - Peng,Yun PB - University of Maryland at College Park CY - College Park, MD, USA ER - TY - RPRT T1 - Six Generations of Building Walkthrough: Final Technical Report to the National Science Foundation Y1 - 1992 A1 - Brooks,Frederick P. A1 - Airey,John A1 - Alspaugh,John A1 - Bell,Andrew A1 - Brown,Randolph A1 - Hill,Curtis A1 - Nimscheck,Uwe A1 - Rheingans,Penny A1 - Rohlf,John A1 - Smith,Dana A1 - Turner,Douglass A1 - Varshney, Amitabh A1 - Wang,Yulan A1 - Weber,Hans A1 - Yuan,Xialin PB - University of North Carolina at Chapel Hill CY - Chapel Hill, NC, USA ER - TY - JOUR T1 - Tracking facilitates 3-D motion estimation JF - Biological Cybernetics Y1 - 1992 A1 - Fermüller, Cornelia A1 - Aloimonos, J. AB - The recently emerging paradigm of Active Vision advocates studying visual problems in form of modules that are directly related to a visual task for observers that are active. Along these lines, we are arguing that in many cases when an object is moving in an unrestricted manner (translation and rotation) in the 3D world, we are just interested in the motion's translational components. For a monocular observer, using only the normal flow — the spatio-temporal derivatives of the image intensity function — we solve the problem of computing the direction of translation and the time to collision. We do not use optical flow since its computation is an ill-posed problem, and in the general case it is not the same as the motion field — the projection of 3D motion on the image plane. The basic idea of our motion parameter estimation strategy lies in the employment of fixation and tracking. Fixation simplifies much of the computation by placing the object at the center of the visual field, and the main advantage of tracking is the accumulation of information over time. We show how tracking is accomplished using normal flow measurements and use it for two different tasks in the solution process. First it serves as a tool to compensate for the lack of existence of an optical flow field and thus to estimate the translation parallel to the image plane; and second it gathers information about the motion component perpendicular to the image plane. VL - 67 SN - 0340-1200 UR - http://dx.doi.org/10.1007/BF00204399 CP - 3 ER - TY - JOUR T1 - Computer based systems engineering workshop JF - Software Engineering Education Y1 - 1991 A1 - Lavi,J. A1 - Agrawala, Ashok K. A1 - Buhr,R. A1 - Jackson,K. A1 - Jackson,M. A1 - Lang,B. AB - Modern computer based systems are complex multi-systems consisting of many connected individual subsystems; each one of them is typically also a multicomputer system. The subsystems in a multi-system can be either geographically distributed or locally connected systems. Typical examples of computer based systems are medical systems, process control systems, communications systems, weapon systems and large information systems.The development of these complex systems requires the establishment of a new engineering discipline in its own right, Computer Based Systems Engineering — CBSE. The definition of the discipline, its current and future practice and the ways to establish and promote it were discussed in an international IEEE workshop held in Neve-Ilan, Israel in May 1990. The major conclusion of the workshop was that CBSE should be established as a new field in its own right. To achieve this goal, the workshop participants recommended that the IEEE Computer Society shall set up a task force for the promotion of the field, the establishment of CBSE Institutes and the development of the educational framework of CBSE. The paper describes the major findings of the workshop that led to these conclusions and recommendations. ER - TY - CONF T1 - DTP: An Efficient Transport Protocol T2 - In Proceedings of the IFIP TC6 Working Conference on ComACM Computing Surveys Y1 - 1991 A1 - Sanghi,Dheeraj A1 - Agrawala, Ashok K. AB - We recently introduced a new flow control scheme, called send-time control, which is based on a deterministic model of virtual circuits in a computer network. In this scheme, the time at which a packet is sent by a source is computed from estimates of round-trip time, traffic in the network and bottleneck service time. In this paper, we describe a new transport protocol, called DTP, which uses send-time control as its flow control scheme. Preliminary measurements of coast-to-coast connections over the Internet show significant performance improvement over TCP, which is the most commonly used transport protocol in the Internet today. Keyword Codes: C.2.2 Keywords: Computer-Communication Networks, Network Protocols 1. Introduction Flow control is one of the most important function at the transport layer of the protocol hierarchy. The function of flow control schemes is to regulate the traffic entering into the network in order to avoid overloading of network resources, thus preventing c... JA - In Proceedings of the IFIP TC6 Working Conference on ComACM Computing Surveys ER - TY - RPRT T1 - Modeling of cross traffic in conjunction with deterministic analysis of queues Y1 - 1991 A1 - Agrawala, Ashok K. A1 - Sanghi,Dheeraj PB - University of Maryland at College Park CY - College Park, MD, USA ER - TY - JOUR T1 - A multi-frame approach to visual motion perception JF - International Journal of Computer Vision Y1 - 1991 A1 - Spetsakis, M. A1 - Aloimonos, J. VL - 6 CP - 3 ER - TY - CONF T1 - Relative depth from motion using normal flow: an active and purposive solution T2 - Proceedings of the IEEE Workshop on Visual Motion, 1991 Y1 - 1991 A1 - Huang, Liuqing A1 - Aloimonos, J. KW - 3D information KW - Automation KW - Computer vision KW - Educational institutions KW - Image motion analysis KW - image recognition KW - Image sequences KW - Laboratories KW - Layout KW - Motion analysis KW - Motion estimation KW - Nonlinear optics KW - normal flow KW - optic flow KW - Optical computing KW - Optical sensors KW - relative depth KW - retinal motion KW - spatiotemporal derivatives KW - time varying image intensity function KW - visual motion AB - The authors show how an active observer can compute the relative depth of (stationary or moving) objects in the field of view using only the spatiotemporal derivatives of the time varying image intensity function. The solution they propose is purposive in the sense that it solves only the relative depth from motion problem and cannot be used for other problems related to motion; active in the sense that the activity of the observer is essential for the solution of the problem. Results indicate that exact computation of retinal motion does not appear to be a necessary first step for some problems related to visual motion. In addition, optic flow, whose computation is an ill-posed problem, is related to the motion of the scene only under very restrictive assumptions. As a result, the use of optic flow in some quantitative motion analysis studies is questionable JA - Proceedings of the IEEE Workshop on Visual Motion, 1991 PB - IEEE SN - 0-8186-2153-2 M3 - 10.1109/WVM.1991.212807 ER - TY - JOUR T1 - A superfamily of ıt Arabidopsis thaliana retrotransposons JF - Genetics Y1 - 1991 A1 - Konieczny,A A1 - Voytas,D. F A1 - Cummings, Michael P. A1 - Ausubel,F. M AB - We describe a superfamily of Arabidopsis thaliana retrotransposable elements that consists of at least ten related families designated Ta1-Ta10. The Ta1 family has been described previously. Two genomic clones representing the Ta2 and Ta3 elements were isolated from an A. thaliana (race Landsberg erecta) lambda library using sequences derived from the reverse transcriptase region of Ta1 as hybridization probes. Nucleotide sequence analysis showed that the Ta1, Ta2 and Ta3 families share greater than 75% amino acid identity in pairwise comparisons of their reverse transcriptase and RNase H genes. In addition to Ta1, Ta2 and Ta3, we identified seven other related retrotransposon families in Landsberg erecta, Ta4-Ta10, using degenerate primers and the polymerase chain reaction to amplify a highly conserved region of retrotransposon-encoded reverse transcriptase. One to two copies of elements Ta2-Ta10 are present in the genomes of the A. thaliana races Landsberg erecta and Columbia indicating that the superfamily comprises at least 0.1% of the A. thaliana genome. The nucleotide sequences of the reverse transcriptase regions of the ten element families place them in the category of copia-like retrotransposons and phylogenetic analysis of the amino acid sequences suggests that horizontal transfer may have played a role in their evolution. VL - 127 CP - 4 ER - TY - JOUR T1 - On the visual mathematics of tracking JF - Image and vision computing Y1 - 1991 A1 - Aloimonos, J. A1 - Tsakiris, D. P VL - 9 CP - 4 ER - TY - BOOK T1 - Visual recovery Y1 - 1991 A1 - Aloimonos, J. A1 - Rosenfeld, A. PB - University of Maryland, Center for Automation Research, Computer Vision Laboratory ER - TY - CONF T1 - Catastrophe theory and computational vision T2 - Proc. AAAI-90 Workshop on Qualitative Vision Y1 - 1990 A1 - Herve, J. A1 - Aloimonos, J. JA - Proc. AAAI-90 Workshop on Qualitative Vision ER - TY - JOUR T1 - Image motion estimation by clustering JF - International Journal of Imaging Systems and Technology Y1 - 1990 A1 - Bandopadhay, Amit A1 - Aloimonos, J. AB - Image motion is estimated by matching feature “interest” points in different frames of video image sequences. The matching is based on local similarity of the displacement vectors. Clustering in the displacement vector space is used to determine the set of plausible match vectors. Subsequently, a similarity-based algorithm performs the actual matching. The feature points are computed using a multiple-filter image decomposition operator. The algorithm has been tested on synthetic as well as real video images. The novelty of the approach is that it handles multiple motions and performs motion segmentation. VL - 2 SN - 1098-1098 UR - http://onlinelibrary.wiley.com/doi/10.1002/ima.1850020409/abstract CP - 4 M3 - 10.1002/ima.1850020409 ER - TY - JOUR T1 - Motion--Boundary Illusions and their Regularization JF - Proceedings of the Royal Society of London. Series B: Biological Sciences Y1 - 1990 A1 - Aloimonos, J. A1 - Huang, Liuqing AB - Humans use various cues to understand the structure of the world from images. One such cue is the contours of an object formed by occlusion or from surface discontinuities. It is known that contours in the image of an object provide various amounts of information about the shape of the object in view, depending on assumptions that the observer makes. Another powerful cue is motion. The ability of the human visual system to discern structure from a motion stimulus is well known and has a solid theoretical and experimental foundation. However, when humans interpret a visual scene they use various cues to understand what they observe, and the interpretation comes from combining the information acquired from the various modules devoted to specific cues. In such an integration of modules it seems that each cue carries a different weight and importance. We performed several experiments where we made sure that the only cues available to the observer were contour and motion. It turns out that when humans combine information from contour and motion to reconstruct the shape of an object in view, if the results of the two modules - shape from contour and structure from motion - are inconsistent, they experience a perceptual result which is due to the combination of the two modules, with the influence of the contour dominating, thus giving rise to the illusion. We describe here examples of such illusions and identify the conditions under which they happen. Finally, we introduce a computational theory for combining contour and motion using the theory of regularization. The theory explains such illusions and predicts many more. The same computational theory, when applied to retinal motion estimation, explains the effect of boundaries on the perception of motion that gives rise to a set of well-known illusions described by Wallach (1976). VL - 242 UR - http://rspb.royalsocietypublishing.org/content/242/1304/75.abstract CP - 1304 M3 - 10.1098/rspb.1990.0106 ER - TY - JOUR T1 - Optimal view caching JF - Information Systems Y1 - 1990 A1 - Amir,Amihood A1 - Roussopoulos, Nick AB - A view in a database is a subset of records selected from several files to satisfy some condition, e.g. the join of two relations.It has been shown that it is more efficient to store pointers to the satisfying records of the base relations rather than the complete records of the view. We are interested in efficient caching of such pointers (in effect constructing the view) when the database lies in secondary storage and only a limited number of buffers exists in memory. A view caching is optimal if it is done with the minimum number of reads from secondary storage. We prove that optimal view caching is NP -complete. VL - 15 SN - 0306-4379 UR - http://www.sciencedirect.com/science/article/pii/030643799090032K CP - 2 M3 - 16/0306-4379(90)90032-K ER - TY - JOUR T1 - Perspective approximations JF - Image and Vision Computing Y1 - 1990 A1 - Aloimonos, J. KW - orthoperspective KW - paraperspective KW - perspective approximations AB - In recent years, researchers in computer vision working on problems such as object recognition, shape reconstruction, shape from texture, shape from contour, pose estimation, etc., have employed in their analyses approximations of the perspective projection as the image formation process. Depending on the task, these approximations often yield very good results and present the advantage of simplicity. Indeed when one relates lengths, angles or areas on the image with the respective units in the 3D world assuming perspective projection, the resulting expressions are very complex, and consequently they complicate the recovery process. However, if we assume that the image is formed with a projection which is a good approximation of the perspective, then the recovery process becomes easier. Two such approximations, are described, the paraperspective and the orthoperspective, and it is shown that for some tasks the error introduced by the use of such an approximation is negligible. Applications of these projections to the problems of shape from texture, shape from contour, and object recognition related problems (such as determining the view vector and pose estimation) are also described. VL - 8 SN - 0262-8856 UR - http://www.sciencedirect.com/science/article/pii/026288569090064C CP - 3 M3 - 16/0262-8856(90)90064-C ER - TY - CONF T1 - Purposive and qualitative active vision T2 - Proceedings of 10th International Conference on Pattern Recognition, 1990 Y1 - 1990 A1 - Aloimonos, J. KW - active vision KW - Automation KW - brain models KW - complex visual tasks KW - Computer vision KW - environmental knowledge KW - highly sophisticated navigational tasks KW - HUMANS KW - Image reconstruction KW - intentions KW - Kinetic theory KW - Laboratories KW - Medusa KW - Motion analysis KW - Navigation KW - planning KW - planning (artificial intelligence) KW - purposive-qualitative vision KW - recovery problem KW - Robust stability KW - Robustness KW - SHAPE KW - stability AB - The traditional view of the problem of computer vision as a recovery problem is questioned, and the paradigm of purposive-qualitative vision is offered as an alternative. This paradigm considers vision as a general recognition problem (recognition of objects, patterns or situations). To demonstrate the usefulness of the framework, the design of the Medusa of CVL is described. It is noted that this machine can perform complex visual tasks without reconstructing the world. If it is provided with intentions, knowledge of the environment, and planning capabilities, it can perform highly sophisticated navigational tasks. It is explained why the traditional structure from motion problem cannot be solved in some cases and why there is reason to be pessimistic about the optimal performance of a structure from motion module. New directions for future research on this problem in the recovery paradigm, e.g., research on stability or robustness, are suggested JA - Proceedings of 10th International Conference on Pattern Recognition, 1990 PB - IEEE VL - i SN - 0-8186-2062-5 M3 - 10.1109/ICPR.1990.118128 ER - TY - JOUR T1 - The structure, distribution and evolution of the ıt Ta1 retrotransposable element family of ıt Arabidopsis thaliana JF - Genetics Y1 - 1990 A1 - Voytas,D. F A1 - Konieczny,A A1 - Cummings, Michael P. A1 - Ausubel,F. M AB - The Ta1 elements are a low copy number, copia-like retrotransposable element family of Arabidopsis thaliana. Six Ta1 insertions comprise all of the Ta1 element copies found in three geographically diverse A. thaliana races. These six elements occupy three distinct target sites: Ta1-1 is located on chromosome 5 and is common to all three races (Col-0, Kas-1 and La-0). Ta1-2 is present in two races on chromosome 4 (Kas-1 and La-0), and Ta1-3, also located on chromosome 4, is present only in one race (La-0). The six Ta1 insertions share greater than 96% nucleotide identity, yet are likely to be incapable of further transposition due to deletions or nucleotide changes that alter either the coding capacity of the elements or conserved protein domains required for retrotransposition. Nucleotide sequence comparisons of these elements and the distribution of Ta1 among 12 additional A. thaliana geographical races suggest that Ta1-1 predated the global dispersal of A. thaliana. As the species spread throughout the world, two additional transposition events occurred which gave rise first to Ta1-2 and finally to Ta1-3. VL - 126 CP - 3 ER - TY - JOUR T1 - Structure from motion using line correspondences JF - International Journal of Computer VisionInt J Comput Vision Y1 - 1990 A1 - Spetsakis, Minas E. A1 - Aloimonos, J. VL - 4 SN - 0920-5691 UR - http://www.springerlink.com/content/r4h10053528335k2/ CP - 3 M3 - 10.1007/BF00054994 ER - TY - CONF T1 - A Unified Theory Of Structure From Motion T2 - Proceedings of DARPA Image Understanding Workshop Y1 - 1990 A1 - Spetsakis, M. A1 - Aloimonos, J. JA - Proceedings of DARPA Image Understanding Workshop ER - TY - JOUR T1 - Distributed Checkpointing for Globally Consistent States of Databases JF - IEEE Trans. Softw. Eng. Y1 - 1989 A1 - Son,Sang Hyuk A1 - Agrawala, Ashok K. KW - Availability KW - checkpoint KW - consistency KW - distributed database KW - noninterference KW - recovery KW - transaction VL - 15 SN - 0098-5589 UR - http://dx.doi.org/10.1109/TSE.1989.559763 CP - 10 M3 - 10.1109/TSE.1989.559763 ER - TY - JOUR T1 - Dynamic bin packing problem JF - SIAM Journal on Computing Y1 - 1989 A1 - Dikshit,Piyush A1 - Guimaraes,Katia A1 - Ramamurthy,Maya A1 - Agrawala, Ashok K. A1 - Larsen,Ronald L AB - In a previous work we have defined a general architecture model for autonomous systems, which can be mapped easily to describe the functions of any automated system (SDAG-86-01). In this note, we use the model to describe the problem of thermal management in space stations. First we briefly review the architecture, then we present the environment of our application, and finally we detail the specific function for each functional block of the architecture for that environment. VL - 12 CP - 14 ER - TY - JOUR T1 - On the kinetic depth effect JF - Biological cybernetics Y1 - 1989 A1 - Aloimonos, J. A1 - Brown, C. M. VL - 60 CP - 6 ER - TY - JOUR T1 - Learning early-vision computations JF - JOSA A Y1 - 1989 A1 - Aloimonos, J. A1 - Shulman, D. VL - 6 CP - 6 ER - TY - CONF T1 - Optimal motion estimation T2 - Workshop on Visual Motion, 1989.,Proceedings Y1 - 1989 A1 - Spetsakis, M. E A1 - Aloimonos, J. KW - 3D motion interpretation KW - Automation KW - Computer vision KW - computerised pattern recognition KW - computerised picture processing KW - constraint minimization KW - dynamic imagery KW - Educational institutions KW - feature correspondences KW - Gaussian noise KW - Image motion analysis KW - Laboratories KW - maximum-likelihood-principle KW - Minimization methods KW - Motion analysis KW - Motion estimation KW - motion parameters KW - moving object KW - multiple frames KW - nonlinear constraint KW - Optical computing KW - optimal motion estimation KW - parameter estimation KW - quadratic minimization KW - quadratic programming KW - redundancy KW - rigidity assumption KW - robotics applications KW - structure-from-motion KW - successive images KW - two-frame AB - The problem of using feature correspondences to recover the structure and 3D motion of a moving object from its successive images is analyzed. They formulate the problem as a quadratic minimization problem with a nonlinear constraint. Then they derive the condition for the solution to be optimal under the assumption of Gaussian noise in the input, in the maximum-likelihood-principle sense. The authors present two efficient ways to approximate it and discuss some inherent limitations of the structure-from-motion problem when two frames are used that should be taken into account in robotics applications that involve dynamic imagery. Finally, it is shown that some of the difficulties inherent in the two-frame approach disappear when redundancy in the data is introduced. This is concluded from experiments using a structure-from-motion algorithm that is based on multiple frames and uses only the rigidity assumption JA - Workshop on Visual Motion, 1989.,Proceedings PB - IEEE SN - 0-8186-1903-1 M3 - 10.1109/WVM.1989.47114 ER - TY - JOUR T1 - Ordering techniques for the preconditioned conjugate gradient method on parallel computers JF - Computer Physics Communications Y1 - 1989 A1 - Elman, Howard A1 - Agrón, Elvira AB - We consider the parallel implementation of the preconditioned conjugate gradient method using multicolor incomplete factorization as preconditioners. We discuss numerical experiments on sample problems arising from elliptic partial differential equations, together with an analytic study of the effects of communication and artihmetic costs on loosely coupled architectures. Our main conclusion is that multicolor orderings result in slower convergence of the preconditioned conjugate gradient method than natural orderings, but that the lower parallel costs of the multicolor techniques typically make their overall performance better. VL - 53 SN - 0010-4655 UR - http://www.sciencedirect.com/science/article/pii/0010465589901641 CP - 1-3 M3 - 16/0010-4655(89)90164-1 ER - TY - CONF T1 - Unification and integration of visual modules T2 - Proceedings Image Understanding Workshop Y1 - 1989 A1 - Aloimonos, J. JA - Proceedings Image Understanding Workshop ER - TY - JOUR T1 - Unifying Shading and Texture Through an Active Observer JF - Proceedings of the Royal Society of London. B. Biological Sciences Y1 - 1989 A1 - Aloimonos, J. AB - Shading (variations of image intensity) provides an important cue for understanding the shape of three-dimensional surfaces from monocular views. On the other hand. texture (distribution of discontinuities on the surface) is a strong cue for recovering surface orientation by using monocular images. But given the image of an object or scene, what technique should we use to recover the shape of what is imaged? Resolution of shape from shading requires knowledge of the reflectance of the imaged surface and, usually, the fact that it is smooth (i.e. it shows no discontinuities). Determination of shape from texture requires knowledge of the distribution of surface markings (i.e. discontinuities). One might expect that one method would work when the other does not. I present a theory on how an active observer can determine shape from the image of an object or scene regardless of whether the image is shaded, textured. or both, and without any knowledge of reflectance maps or the distribution of surface markings. The approach is successful because the active observer is able to manipulate the constraints behind the perceptual phenomenon at hand and thus derive a simple solution. Several experimental results are presented with real and synthetic images. VL - 238 UR - http://rspb.royalsocietypublishing.org/content/238/1290/25.abstract CP - 1290 M3 - 10.1098/rspb.1989.0064 ER - TY - JOUR T1 - Active vision JF - International Journal of Computer Vision Y1 - 1988 A1 - Aloimonos, J. A1 - Weiss, I. A1 - Bandyopadhyay, A. VL - 1 CP - 4 ER - TY - BOOK T1 - Correspondenceless detection of depth and motion for a planar surface Y1 - 1988 A1 - Aloimonos, J. A1 - Hervé, J. Y PB - University of Maryland ER - TY - CONF T1 - The Maryland approach to image understanding T2 - Science Applications International Corp, Proceedings: Image Understanding Workshop, Y1 - 1988 A1 - Aloimonos, J. A1 - Davis, Larry S. A1 - Rosenfeld, A. JA - Science Applications International Corp, Proceedings: Image Understanding Workshop, VL - 1 ER - TY - CONF T1 - Optimal Computing Of Structure From Motion Using Point Correspondences In Two Frames T2 - Proceedings of Second International Conference on Computer Vision Y1 - 1988 A1 - Spetsakis, M. E A1 - Aloimonos, J. KW - Automation KW - Computer vision KW - Educational institutions KW - Gaussian noise KW - Image motion analysis KW - Laboratories KW - Least squares approximation KW - Least squares methods KW - Motion estimation KW - Optical computing JA - Proceedings of Second International Conference on Computer Vision PB - IEEE SN - 0-8186-0883-8 M3 - 10.1109/CCV.1988.590022 ER - TY - JOUR T1 - Parallel construction of a suffix tree with applications JF - Algorithmica Y1 - 1988 A1 - Apostolico,A. A1 - Iliopoulos,C. A1 - Landau,G. M A1 - Schieber,B. A1 - Vishkin, Uzi VL - 3 CP - 1 ER - TY - JOUR T1 - Robust computation of intrinsic images from multiple cues JF - Advances in Computer Vision Y1 - 1988 A1 - Aloimonos, J. A1 - Brown, C. M. VL - 1 ER - TY - JOUR T1 - Shape from patterns: Regularization JF - International journal of computer vision Y1 - 1988 A1 - Aloimonos, J. A1 - Swain, M. VL - 2 CP - 2 ER - TY - JOUR T1 - Shape from texture JF - Biological Cybernetics Y1 - 1988 A1 - Aloimonos, J. VL - 58 CP - 5 ER - TY - CONF T1 - Using flow field divergence for obstacle avoidance in visual navigation T2 - Science Applications International Corp, Proceedings: Image Understanding Workshop, Y1 - 1988 A1 - Nelson, R. A1 - Aloimonos, J. JA - Science Applications International Corp, Proceedings: Image Understanding Workshop, VL - 2 ER - TY - JOUR T1 - Visual shape computation JF - Proceedings of the IEEE Y1 - 1988 A1 - Aloimonos, J. KW - a priori knowledge KW - active vision KW - computational problems KW - Computer vision KW - computing shaping from motion KW - contour KW - cues KW - Focusing KW - HUMANS KW - ill posed problems KW - Machine vision KW - Psychology KW - regularization theory KW - RETINA KW - sense of Hadamard KW - shading KW - SHAPE KW - space of possible solutions KW - Stereo vision KW - Surface texture KW - TEXTURE KW - visual shape computation KW - Visual system AB - Perceptual processes responsible for computing shape from several cues, including shading, texture, contour, and stereo, are examined. It is noted that these computational problems, as well as that of computing shaping from motion, are ill-posed in the sense of Hadamard. It is suggested that regularization theory can be used along with a priori knowledge to restrict the space of possible solutions, and thus restore the problem's well-prosedness. Some alternative methods are outlined, and the idea of active vision is explored briefly in connection with the problem VL - 76 SN - 0018-9219 CP - 8 M3 - 10.1109/5.5964 ER - TY - CONF T1 - Determining three dimensional transformation parameters from images: Theory T2 - 1987 IEEE International Conference on Robotics and Automation. Proceedings Y1 - 1987 A1 - Ito, E. A1 - Aloimonos, J. KW - Automation KW - Computational modeling KW - Educational institutions KW - Image motion analysis KW - Indium tin oxide KW - Linear systems KW - Motion estimation KW - Optical computing KW - Robots KW - Simulated annealing AB - We present a theory for the determination of the three dimensional transformation parameters of an object, from its images. The input to this process is the image intensity function and its temporal derivative. In particular, our results are: 1) If the structure of the transforming object in view is known, then the transformation parameters are determined from the solution of a linear system. Rigid motion is a special ease of our theory. 2)If the structure of the object in view is not known, then both the structure and transformation parameters may be computed through a hill climbing or simulated annealing algorithm. JA - 1987 IEEE International Conference on Robotics and Automation. Proceedings PB - IEEE VL - 4 M3 - 10.1109/ROBOT.1987.1088011 ER - TY - JOUR T1 - Learning shape computations JF - Proc. DARPA Image Y1 - 1987 A1 - Aloimonos, J. A1 - Shulman, D. ER - TY - BOOK T1 - A robust algorithm for determining the translation of a rigidly moving surface without correspondence, for robotics applications Y1 - 1987 A1 - Basu, A. A1 - Aloimonos, J. PB - University of Maryland ER - TY - JOUR T1 - Spatiotemporal blur paths for image flow estimation (A) JF - Journal of the Optical Society of America A Y1 - 1987 A1 - Spetsakis, M. E A1 - Aloimonos, J. VL - 4 ER - TY - BOOK T1 - Structure from Motion from Line Correspondencies: New Results Y1 - 1987 A1 - Science, University of Maryland at College Park. Dept. of Computer A1 - Spetsakis, M. E A1 - Aloimonos, J. A1 - Research, University of Maryland at College Park. Center for Automation ER - TY - JOUR T1 - Tight comparison bounds on the complexity of parallel sorting JF - SIAM J. Comput. Y1 - 1987 A1 - Azar,Y. A1 - Vishkin, Uzi VL - 16 CP - 3 ER - TY - JOUR T1 - Time Stress Effects on Two Menu Selection Systems JF - Proceedings of the Human Factors and Ergonomics Society Annual MeetingProceedings of the Human Factors and Ergonomics Society Annual Meeting Y1 - 1987 A1 - Wallace,Daniel F A1 - Anderson,Nancy S A1 - Shneiderman, Ben AB - The optimal number of menu items per display screen has been the topic of considerable debate and study. On the one hand, some designers have packed many items into each menu to conserve space and reduce the number of menus, whereas on the other hand there are designers who prefer a sparse display for menu structures and other videotex information. This study evaluated the effects of a broad/shallow menu compared to a narrow/deep menu structure under two conditions of time stress for inexperienced users. Results indicated that time stress both slowed performance, and increased errors. In addition, it was demonstrated that the broad/shallow menu was faster and resulted in fewer errors. Implications for menu design are discussed. VL - 31 SN - 1071-1813, UR - http://pro.sagepub.com/content/31/7/727 CP - 7 M3 - 10.1177/154193128703100708 ER - TY - JOUR T1 - Algorithm for concurrency control in replicated databases. JF - COMP. SYST. SCI. ENG. Y1 - 1986 A1 - Son,S. H A1 - Agrawala, Ashok K. AB - A replicated database system is a distributed database system in which some data objects are stored redundantly at multiple sites to improve the reliability of the system. Without proper control mechanisms, the consistency of a replicated database system could be violated. A new scheme to increase the reliability as well as the degree of concurrency is described. It allows transactions to operate on a data object so long as one or more token copies are available. The scheme also exploits the fact that, for recovery reasons, there are two values for one data object. It is proved that transactions executed according to this scheme preserve consistency. VL - 1 CP - 2 ER - TY - RPRT T1 - Computing Intrinsic Images. Y1 - 1986 A1 - Aloimonos, J. KW - *ARTIFICIAL INTELLIGENCE KW - *COMPUTERS KW - *IMAGE PROCESSING KW - *VISION KW - algorithms KW - CAMERAS KW - CATASTROPHIC CONDITIONS KW - COMPUTATIONS KW - CYBERNETICS KW - ERRORS KW - HUMANS KW - IMAGES KW - INTENSITY KW - LOW LEVEL KW - MATHEMATICS KW - MOTION KW - RETINA KW - Robots KW - SHADOWS KW - SHAPE KW - TEXTURE KW - THEORY KW - THESES. AB - Low level modern computer vision is not domain dependent, but concentrates on problems that correspond to identifiable modules in the human visual system. Several theories have been proposed in the literature for the computation of shape from shading, shape from texture, retinal motion from spatiotemporal derivatives of the image intensity function and the like. The problems with the existing approach are basically the following: (1) The employed assumptions are very strong and so most of the algorithms fail when applied to real images. (2) Usually the constraints from the geometry and the physics of the problem are not enough to guarantee uniqueness of the computed parameters. (3) In most cases the resulting algorithms are not robust, in the sense that if there is a slight error in the input this results in a catastrophic error in the output. In this thesis the problem of machine vision is explored from its basics. A low level mathematical theory is presented for the unique robust computation of intrinsic parameters. The computational aspect of the theory envisages a cooperative highly parallel implementation, bringing in information from five different sources (shading, texture, motion, contour and stereo), to resolve ambiguities and ensure uniqueness and stability of the intrinsic parameters. The problems of shape from texture, shape from shading and motion, visual motion analysis and shape and motion from contour are analyzed in detail. UR - http://stinet.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA189440 ER - TY - RPRT T1 - Determining the Translation of a Rigidly Moving Surface, without Correspondence, Y1 - 1986 A1 - Aloimonos, J. A1 - Basu, Anup KW - *IMAGE PROCESSING KW - *OPTICAL DETECTION KW - *Translation(Image processing) KW - CAMERAS KW - Computer vision KW - COMPUTERS KW - IMMUNITY. KW - MOTION KW - MOVING TARGETS KW - NOISE KW - OPTICAL DETECTION AND DETECTORS KW - SURFACES KW - THREE DIMENSIONAL KW - VISION AB - A method is presented for the recovery of the three-dimensional translation of a rigidly moving textured object from its images. The novelty of the method consists of the fact that four cameras are used in order to avoid the solution of the correspondence problem. The method seems to be immune to small noise percentages and to have good behavior when the noise increases. Keywords: Computer vision. UR - http://stinet.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA179409 ER - TY - JOUR T1 - The parsimonious covering model for inexact abductive reasoning in diagnostic systems JF - Recent Developments in the Theory and Applications of Fuzzy Sets. Proceedings of NAFIPS Y1 - 1986 A1 - Ahuja,S. B A1 - Reggia, James A. ER - TY - CONF T1 - Practicality of non-interfering checkpoints in distributed database systems T2 - IEEE Real-Time Systems Symposium, New Orleans, Louisiana Y1 - 1986 A1 - Son,S. H A1 - Agrawala, Ashok K. JA - IEEE Real-Time Systems Symposium, New Orleans, Louisiana ER - TY - CONF T1 - Shape and 3-d motion from contour without point to point correspondences: General principles T2 - CVPR86 Y1 - 1986 A1 - Aloimonos, J. A1 - Basu, A. JA - CVPR86 ER - TY - CONF T1 - Tight complexity bounds for parallel comparison sorting T2 - 27th Annual Symposium on Foundations of Computer Science Y1 - 1986 A1 - Alon,N. A1 - Azar,Y. A1 - Vishkin, Uzi JA - 27th Annual Symposium on Foundations of Computer Science ER - TY - CONF T1 - Using abductive inferencing to derive complex error classifications for discrete sequential processes T2 - Proceedings of the 19th annual symposium on Simulation Y1 - 1986 A1 - Ahuja,S. B A1 - Reggia, James A. JA - Proceedings of the 19th annual symposium on Simulation ER - TY - CONF T1 - Contour, orientation and motion T2 - Proceedings: Image Understanding Workshop (Miami Beach, FL, December 9–10, 1985) Y1 - 1985 A1 - Aloimonos, J. A1 - Basu, A. A1 - Brown, C. M. JA - Proceedings: Image Understanding Workshop (Miami Beach, FL, December 9–10, 1985) ER - TY - BOOK T1 - Detection of Surface Orientation and Motion from Texture: The Case of Planes Y1 - 1985 A1 - Aloimonos, J. A1 - Chou, P. B A1 - Science, University of Rochester. Dept. of Computer PB - Dept. of Computer Science, University of Rochester ER - TY - CONF T1 - Direct processing of curvilinear sensor motion from a sequence of perspective images T2 - Proc. Workshop on Computer Vision: Representation and Control Y1 - 1984 A1 - Aloimonos, J. A1 - Brown, C. M. JA - Proc. Workshop on Computer Vision: Representation and Control VL - 72 ER - TY - JOUR T1 - Finding Euler tours in parallel* 1 JF - Journal of Computer and System Sciences Y1 - 1984 A1 - Atallah,M. A1 - Vishkin, Uzi VL - 29 CP - 3 ER - TY - JOUR T1 - The relationship between optical flow and surface orientation JF - Proc. of the 7-th ICPR, Montreal-Canada Y1 - 1984 A1 - Aloimonos, J. A1 - Brown, C. M. ER - TY - CONF T1 - Simulation of phonemic errors using artificial intelligence symbol processing techniques T2 - Proceedings of the 17th annual symposium on Simulation Y1 - 1984 A1 - Reggia, James A. A1 - Ahuja,S. B JA - Proceedings of the 17th annual symposium on Simulation ER - TY - JOUR T1 - SLIPS JF - Journal of Medical Systems Y1 - 1984 A1 - Morris,M. S A1 - Reggia, James A. A1 - Ahuja,S. B A1 - Hart,J. A1 - Watson,V. VL - 8 CP - 3 ER - TY - JOUR T1 - parallel MAX-FLOW algorithm JF - Journal of Algorithms Y1 - 1982 A1 - Shiloach,Y. A1 - Vishkin, Uzi A1 - An,O. VL - 3 ER - TY - JOUR T1 - Transcription of cloned tRNA and 5S RNA genes in a Drosophila cell free extract JF - Nucleic Acids ResearchNucl. Acids Res. Y1 - 1981 A1 - Dingermann,Theodor A1 - Sharp,Stephen A1 - Appel,Bernd A1 - DeFranco,Donald A1 - Mount, Stephen M. A1 - Heiermann,Reinhard A1 - Pongs,Olaf A1 - Söll,Dieter AB - We describe the preparation of a cell-free extract from Drosophila Kc cells which allows transcription of a variety of cloned eukaryotic RNA polymerase III genes. The extract has low RNA-processing nuclease activity and thus the major products obtained are primary transcripts. VL - 9 SN - 0305-1048, 1362-4962 UR - http://nar.oxfordjournals.org/content/9/16/3907 CP - 16 M3 - 10.1093/nar/9.16.3907 ER - TY - RPRT T1 - An Algorithm for Mutual Exclusion in Computer Networks. Y1 - 1980 A1 - Agrawala, Ashok K. A1 - Ricart, G. AB - An algorithm is proposed which creates mutual exclusion in a computer network whose nodes can communicate only by messages and do not share memory. The algorithm sends only 2*(N-1) Messages, where N is the number of nodes in the network, per critical section invocation. This number of messages is a minimum if parallel, distributed, symmetric control is used; hence, the algorithm is optimal in this minimal under some general assumptions. Like Lamport's 'bakery algorithm,' unbounded sequence numbers are used to provide first-come first-served priority into the critical section. It is shown that the number can be contained in a fixed amount of memory by storing it as the residue of a modulus. The number of messages required to implement the exclusion can be reduced by using sequential node-by-node processing, by using broadcast message techniques or by sending information through timing channels. The readers and writers problem is solved by a simple modification of the algorithm. The modifications necessary to make the algorithm robust are described. PB - Department of Computer Science, University of Maryland, College Park ER - TY - JOUR T1 - Correspondence from Correspondence JF - Optical Society of America, Topical Meeting on Machine Vision Y1 - 1980 A1 - Aloimonos, J. A1 - Kamgar-Parsi,Behrooz KW - ALIGNMENT KW - COMPUTATION KW - Error analysis KW - IMAGE PROCESSING KW - IMAGES KW - STEREOSCOPIC VISION KW - VECTORS (MATHEMATICS) AB - Image matching (or registration), is in general terms, aligning two identical or similar images or parts of images, and it is basic to a number of vision problems. These include optical nagivation (also known as motion analysis), stereo image interpretation, object analysis, change detection and others. The difficult part of all these problems, is the matching problem, i.e., the computation of the correspondence of elements in the different views. The computation of correspondence, in both the stereo and the motion problem is impossible without the use of some assumptions about the visual world and various researchers have proposed several theories for the computation of visual correspondence that worked well for the domains that fitted their assumptions. Studied here is the problem of the computation of visual correspondence, under the assumption that some values of the correspondence function are already known. The mathematical constraints that are needed for growing a solution for the correspondence function from points where its value is known are developed. UR - http://adsabs.harvard.edu/abs/1980osa..meet...46A ER - TY - RPRT T1 - The Effect of the Future in Work Distribution. Y1 - 1980 A1 - Agrawala, Ashok K. A1 - Ricart, G. AB - A controller is considered which routes arrivals among several servers of different speeds. A decision which sends work to the server which will complete it soonest does not optimize the average completion time (mean flow time) because it doesn't take into account the impact of the decision on future arrivals. This impact on future arrivals, the 'future effect', can be significant at high arrival rates. An estimate of the size of the future effect is derived and controllers which take it into account in routing decisions can reduce the average completion time to near optimum. The effect is most pronounced when the service requirements for arrivals are nearly constant, server speeds are markedly different, and the arrival rate is close to the system's capacity. A controller considering the future effect will more heavily weigh a potential server's backlog than the arrival's service time when making a routing decision PB - COMPUTER SCIENCE CENTER, UNIVERSITY OF MARYLAND COLLEGE PARK ER - TY - BOOK T1 - A guide to major job accounting systems: the Logger system of the UNIVAC 1100 series operating system Y1 - 1978 A1 - Mohr,Jeffrey Myron A1 - Agrawala, Ashok K. A1 - Flannagan,J. F. KW - Accounting KW - Business & Economics / Accounting / General KW - Electronic digital computers KW - EXEC 8 (Electronic computer system) KW - Reference / Questions & Answers KW - Univac 1100 series (Computer) KW - Univac computer PB - U.S. Dept. of Commerce, National Bureau of Standards : for sale by the Supt. of Docs., U.S. Govt. Print. Off. ER - TY - BOOK T1 - Machine recognition of patterns Y1 - 1977 A1 - Agrawala, Ashok K. PB - John Wiley & Sons Canada, Limited ER - TY - CONF T1 - The relationship between the pattern recognition problem and the workload characterization problem T2 - 1977 CMG Conference Y1 - 1977 A1 - Agrawala, Ashok K. A1 - Mohr,J. M JA - 1977 CMG Conference ER - TY - CONF T1 - Use of peer ratings in evaluating computer program quality T2 - Proceedings of the fifteenth annual SIGCPR conference Y1 - 1977 A1 - Anderson,Nancy A1 - Shneiderman, Ben AB - Peer review techniques can be useful tools for supplementing programmer education, improving cooperation and communication within programming teams, and providing programmer self-evaluation. This paper will explore the benefits of peer review for practicing professional programmers and describe a framework for administration of an annual or semi-annual peer review process. JA - Proceedings of the fifteenth annual SIGCPR conference T3 - SIGCPR '77 PB - ACM CY - New York, NY, USA UR - http://doi.acm.org/10.1145/800100.803247 M3 - 10.1145/800100.803247 ER - TY - BOOK T1 - The EXEC-8 Log System: Error Analysis Y1 - 1976 A1 - Mohr,J. M A1 - Agrawala, Ashok K. A1 - Flanagan,J. F. A1 - Science,University of Maryland. Dept. of Computer PB - University of Maryland, Dept. of Computer Science ER - TY - BOOK T1 - Foundations of microprogramming: architecture, software, and applications Y1 - 1976 A1 - Agrawala, Ashok K. A1 - Rauscher,T. G PB - Academic Press ER - TY - BOOK T1 - Pattern Recognition Y1 - 1973 A1 - Kanal,L. N A1 - Agrawala, Ashok K. PB - Computer Science Center, University of Maryland ER -