New year’s resolutions for software quality - Basili, Victor R.; Boehm,B.; Davis,A.; Humphrey,W. S; Leveson,N.; Mead,N. R; Musa,J. D; Parnas,D. L; Pfleeger,S. L; Weyuker,E. (IEEE Software, 2004)
In the spirit of making resolutions for betterment in the New Year, ten distinguished individuals in the software quality field offer their recommendations on how organizations can improve software quality In the spirit of making resolutions for betterment in the New Year, ten distinguished individuals in the software quality field offer their recommendations on how organizations can improve software quality.

A novel approach to removing intersymbol interference from spin-stand images - Mayergoyz, Issak D; Tse,C.; Krafft,C.; McAvoy,P. (Magnetics, IEEE Transactions on, 2004)
A novel intersymbol interference (ISI) removal technique based on the "response function" characterization of giant-magnetoresistive heads is presented. It is demonstrated that the ISI-free readback image that corresponds to the actual underlying magnetization patterns can be extracted from the ISI-distorted readback signal through deconvolution. A new image deconvolution algorithm has been implemented, and it has been shown that it effectively removes the ISI distortions.
Keywords: algorithm; characterization; Deconvolution; function; function; giant; giant-magnetoresistive; Head; heads; image; image; imaging; Interference; interference; intersymbol; ISI-distorted; ISI-free; magnetic; magnetization; magnetoresistance; patterns; readback; removal; response; signal; spin-stand; suppression

Np bracketing by maximum entropy tagging and SVM reranking - Daumé, Hal; Marcu,D. (Proceedings of EMNLP, 2004)

Pandemic strains of O3:K6 Vibrio parahaemolyticus in the aquatic environment of Bangladesh - Islam,M. S.; Tasmin,Rizwana; Khan,Sirajul I. s l a m; Bakht,Habibul B. M.; Mahmood,Zahid H. a y a t; Rahman,M. Z. i a u r; Bhuiyan,Nurul A. m i n; Nishibuchi,Mitsuaki; Nair,G. B. a l a k r i s h; Sack,R. B. r a d l e y; Huq,Anwar; Rita R Colwell; et al. (Canadian Journal of Microbiology, 2004)
A total of 1500 environmental strains of Vibrio parahaemolyticus, isolated from the aquatic environment of Bangladesh, were screened for the presence of a major V. parahaemolyticus virulence factor, the thermostable direct haemolysin (tdh) gene, by the colony blot hybridization method using a digoxigenin-labeled tdh gene probe. Of 1500 strains, 5 carried the tdh sequence, which was further confirmed by PCR using primers specific for the tdh gene. Examination by PCR confirmed that the 5 strains were V. parahamolyticus and lacked the thermostable direct haemolysin-related haemolysin (trh) gene, the alternative major virulence gene known to be absent in pandemic strains. All 5 strains gave positive Kanagawa phenomenon reaction with characteristic beta-haemolysis on Wagatsuma agar medium. Southern blot analysis of the HindIII-digested chromosomal DNA demonstrated, in all 5 strains, the presence of 2 tdh genes common to strains positive for Kanagawa phenomenon. However, the 5 strains were found to belong to 3 different serotypes (O3:K29, O4:K37, and O3:K6). The 2 with pandemic serotype O3:K6 gave positive results in group-specific PCR and ORF8 PCR assays, characteristics unique to the pandemic clone. Clonal variations among the 5 isolates were analyzed by comparing RAPD and ribotyping patterns. Results showed different patterns for the 3 serotypes, but the pattern was identical among the O3:K6 strains. This is the first report on the isolation of pandemic O3:K6 strains of V. parahaemolyticus from the aquatic environment of Bangladesh.

PAWN: Producer-Archive Workflow Network in support of digital preservation - Smorul,M.; JaJa, Joseph F.; Wang, Y.; McCall,F. (Instititue for Advanced Computer Studies, Univ of Maryland, College Park, 2004)
We describe the design and the implementation of the PAWN (Producer – ArchiveWorkflow Network) environment to enable secure and distributed ingestion of digital objects into a persistent archive. PAWN was developed to capture the core elements required for long term preservation of digital objects as identified by previous research in the digital library and archiving communities. In fact, PAWN can be viewed as an implementation of the Ingest Process as defined by the Open Archival Information System (OAIS) Reference Model, and is currently being used to ingest significant collections into a pilot persistent archive developed through a collaboration between the San Diego Supercomputer Center, the University of Maryland, and the National Archives and Records Administration. We make use of METS (Metadata Encoding and Transmission Standards) to encapsulate content, structural, descriptive, and preservation metadata. The basic software components are based on open standards and web technologies, and hence are platform independent.

A phrase-based hmm approach to document/abstract alignment - Daumé, Hal; Marcu,D. (Proceedings of EMNLP, 2004)

Preserving distributed systems critical properties: a model-driven approach - Yilmaz,C.; Memon, Atif M.; Porter, Adam; Krishna,A. S; Schmidt,D. C; Gokhale,A.; Natarajan,B. (Software, IEEE, 2004)
The need for creating predictability in distributed systems is most often specified in terms of quality-of-service (QoS) requirements, which help define the acceptable levels of dependability with which capabilities such as processing capacity, data throughput, or service availability reach users. For longer-term properties such as scalability, maintainability, adaptability, and system security, we can similarly use persistent software attributes (PSAs) to specify how and to what degree such properties must remain intact as a network expands and evolves over time. The Skoll distributed continuous software quality assurance process helps to identify viable system and software configurations for meeting stringent QOS and PSA requirements by coordinating the use of distributed computing resources. The authors tested their process using the large, rapidly evolving ACE+TAO middleware suite.
Keywords: configuration management; formal verification; Middleware; middleware suite; model-driven approach; persistent software attributes; QoS requirements; Quality assurance; quality of service; quality-of-service; Skoll distributed computing resources; software configuration; Software maintenance; Software quality; software quality assurance process; system dependability

Proactive key distribution using neighbor graphs - Mishra,A.; Min Ho Shin; Petroni,N. L.; Clancy,T. C; Arbaugh, William A. (IEEE Wireless Communications, 2004)
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.
Keywords: access points; Authentication; authentication time; Base stations; Communication system security; Delay; graph theory; GSM; IEEE 802.11 handoff; Land mobile radio cellular systems; Message authentication; mobile radio; Multiaccess communication; neighbor graph; Network topology; Roaming; telecommunication security; Telephone sets; user mobility; Wi-Fi networks; wireless data networks; Wireless LAN; Wireless networks

Probabilistic analysis of kernel principal components - Zhou, S.; Chellapa, Rama; Moghaddam, B. (NIPS, 2004)
This paper presents a probabilistic analysis of kernel principal compo-nents by unifying the theory of probabilistic principal component analy- sis and kernel principal component analysis. It is shown that, while the kernel component enhances the nonlinear modeling power, the proba- bilistic structure offers (i) a mixture model for nonlinear data structure containing nonlinear sub-structures, and (ii) an effective classification scheme. It turns out that the original loading matrix is replaced by a newly defined empirical loading matrix. The expectation/maximization algorithm for learning parameters of interest is also presented.

Project highlight: toward the statistical knowledge network - Marchionini,Gary; Haas,Stephanie; Shneiderman, Ben; Plaisant, Catherine; Hert,Carol A. (Proceedings of the 2004 annual national conference on Digital government research, 2004)
This project aims to help people find and understand government statistical information. To achieve this goal, we envision a statistical knowledge network that brings stakeholders from government at all levels together with citizens who provide or seek statistical information. The linchpin of this network is a series of human-computer interfaces that facilitate information seeking, understanding, and use. In turn, these interfaces depend on high-quality metadata and intra-agency cooperation. In this briefing, we summarize our accomplishments in the second year of the project.

Reconfigurable optical wireless sensor networks - Llorca,Jaime; Desai,Aniket; Vishkin, Uzi; Davis,Christopher C.; Milner,Stuart D (Proceedings of SPIE, 2004)
Optical wireless networks are emerging as a viable, cost effective technology for rapidly deployable broadband sensor communication infrastructures. The use of directional, narrow beam, optical wireless links provides great promise for secure, extremely high data rate communication between fixed or mobile nodes, very suitable for sensor networks in civil and military contexts. The main challenge is to maintain the quality of such networks, as changing atmosphericand platform conditions critically affect their performance. Topology control is used as the means to achieve survivable optical wireless networking under adverse conditions, based on dynamic and autonomous topology reconfiguration. The topology control process involves tracking and acquisition of nodes, assessment of link-state information, collection and distribution of topology data, and the algorithmic solution of an optimal topology. This paper focuses onthe analysis, implementation and evaluation of algorithms and heuristics for selecting the best possible topology in order to optimize a given performance objective while satisfying connectivity constraints. The work done at the physical layer is based on link cost information. A cost measure is defined in terms of bit-error-rate and the heuristics developed seek to form a bi-connected topology which minimizes total network cost. At the network layer a key factor is the traffic matrix, and heuristics were developed in order to minimize congestion, flow-rate or end-to-end delay.

Reducing complexity assumptions for statistically-hiding commitment - Horvitz,O.; Katz, Jonathan; Koo,C. Y; Morselli,R. (In EUROCRYPT, 2004)
Determining the minimal assumptions needed to construct various cryptographic buildingblocks has been a focal point of research in theoretical cryptography. For most — but not all! — cryptographic primitives, complexity assumptions both necessary and sufficient for their existence are known. Here, we revisit the following, decade-old question: what are the minimal assumptions needed to construct a statistically-hiding bit commitment scheme? Previously, it was known how to construct such schemes based on any one-way permutation. In this work, we show that regular one-way functions suffice. We show two constructions of statistically-hiding commitment schemes from regular one-way functions. Our first construction is more direct, and serves as a “stepping-stone” for our second construction which has improved round complexity. Of independent interest, as part of our work we show a compiler transforming any commitment scheme which is statistically-hiding against an honest-but-curious receiver to one which is statistically-hiding against a malicious receiver. This demonstrates the equivalence of these two formulations of the problem.

Reducing storage requirements for biological sequence comparison - Roberts,Michael; Hayes,Wayne; Hunt,Brian R.; Mount, Stephen M.; Yorke,James A. (BioinformaticsBioinformatics, 2004)
Motivation: Comparison of nucleic acid and protein sequences is a fundamental tool of modern bioinformatics. A dominant method of such string matching is the ‘seed-and-extend’ approach, in which occurrences of short subsequences called ‘seeds’ are used to search for potentially longer matches in a large database of sequences. Each such potential match is then checked to see if it extends beyond the seed. To be effective, the seed-and-extend approach needs to catalogue seeds from virtually every substring in the database of search strings. Projects such as mammalian genome assemblies and large-scale protein matching, however, have such large sequence databases that the resulting list of seeds cannot be stored in RAM on a single computer. This significantly slows the matching process.Results: We present a simple and elegant method in which only a small fraction of seeds, called ‘minimizers’, needs to be stored. Using minimizers can speed up string-matching computations by a large factor while missing only a small fraction of the matches found using all seeds.

RT-S: Surface rich transcription scoring, methodology, and initial results - Snover,M.; Schwartz,R.; Dorr, Bonnie J; Makhoul,J. (Proc. DARPA Rich Transcription Workshop, 2004)
In this paper we present a methodoly for the scoring ofpunctuation annotated texts, as well as a preliminary system to perform the task. We modify SCLITE’s scoring method- ology to support scoring of punctuation. Using this method- ology, we show that the error rate of an initial automatic sys- tem is comparable to annotator inconsistency. However, the use of multiple references allows us to differentiate between human inconsistencies and system errors.

Schistosoma mansoni genome project: an update - LoVerde,Philip T.; Hirai,Hirohisa; Merrick,Joseph M; Lee,Norman H; El‐Sayed, Najib M. (Parasitology International, 2004)
A schistosome genome project was initiated by the World Health Organization in 1994 with the notion that the best prospects for identifying new targets for drugs, vaccines, and diagnostic development lie in schistosome gene discovery, development of chromosome maps, whole genome sequencing and genome analysis. Schistosoma mansoni has a haploid genome of 270 Mb contained on 8 pairs of chromosomes. It is estimated that the S. mansoni genome contains between 15 000 and 25 000 genes. There are approximately 16 689 ESTs obtained from diverse libraries representing different developmental stages of S. mansoni, deposited in the NCBI EST database. More than half of the deposited sequences correspond to genes of unknown function. Approximately 40-50% of the sequences form unique clusters, suggesting that approximately 20-25% of the total schistosome genes have been discovered. Efforts to develop low resolution chromosome maps are in progress. There is a genome sequencing program underway that will provide 3X sequence coverage of the S. mansoni genome that will result in approximately 95% gene discovery. The genomics era has provided the resources to usher in the era of functional genomics that will involve microarrays to focus on specific metabolic pathways, proteomics to identify relevant proteins and protein-protein interactions to understand critical parasite pathways. Functional genomics is expected to accelerate the development of control and treatment strategies for schistosomiasis.
Keywords: Chromosome mapping; Gene discovery; Genomics; Schistosoma mansoni

Security evaluation for communication-friendly encryption of multimedia - Mao,Yinian; M. Wu (Image Processing, 2004. ICIP '04. 2004 International Conference on, 2004)
This paper addresses the access control issues unique to multimedia, by using a joint signal processing and cryptographic approach to multimedia encryption. Based on three atomic encryption primitives, we present a systematic study on how to strategically integrate different atomic operations to build a video encryption system. We also propose a set of multimedia-specific security metrics to quantify the security against approximation attacks and to complement the existing notion of generic data security. The resulting system can provide superior performance to both generic encryption and its simple adaptation to video in terms of a joint consideration of security, bitrate overhead, and communication friendliness.
Keywords: access; approximation; atomic; attacks; bitrate; coding; communication-friendly; communication; control; cryptography; data; encryption; encryption; generic; joint; method; metrics; multimedia; multimedia-specific; overhead; primitives; processing/cryptographic; Security; security; signal; system; Telecommunication; video

Security issues in IEEE 802.11 wireless local area networks: a survey - Mishra,A.; Petroni Jr,N. L; Arbaugh, William A.; Fraser,T. (Wireless Communications and Mobile Computing, 2004)

Selective refinement queries for volume visualization of unstructured tetrahedral meshes - Cignoni,P.; De Floriani, Leila; Magillo,P.; Puppo,E.; Scopigno,R. (Visualization and Computer Graphics, IEEE Transactions on, 2004)
We address the problem of the efficient visualization of large irregular volume data sets by exploiting a multiresolution model based on tetrahedral meshes. Multiresolution models, also called Level-Of-Detail (LOD) models, allow encoding the whole data set at a virtually continuous range of different resolutions. We have identified a set of queries for extracting meshes at variable resolution from a multiresolution model, based on field values, domain location, or opacity of the transfer function. Such queries allow trading off between resolution and speed in visualization. We define a new compact data structure for encoding a multiresolution tetrahedral mesh built through edge collapses to support selective refinement efficiently and show that such a structure has a storage cost from 3 to 5.5 times lower than standard data structures used for tetrahedral meshes. The data structures and variable resolution queries have been implemented together with state-of-the art visualization techniques in a system for the interactive visualization of three-dimensional scalar fields defined on tetrahedral meshes. Experimental results show that selective refinement queries can support interactive visualization of large data sets.
Keywords: Automated; Signal Processing; Computer-Assisted; Imaging; Computer-Assisted; User-Computer Interface; data structure; geometric modeling; interactive visualization; large data sets; multiresolution model; selective refinement queries; unstructured tetrahedral meshes; variable resolution queries; volume data visualization; data visualisation; mesh generation; query p; Three-Dimensional; Online Systems; Pattern Recognition

Semantic annotation and lexico-syntactic paraphrase - Dorr, Bonnie J; Green,R.; Levin,L.; Rambow,O.; Farwell,D.; Habash,N.; Helmreich,S.; Hovy,E.; Miller,K.J.; Mitamura,T.; others (Proceedings of the 4th International Conference on Language Resources and Evaluation (LREC) Workshop on Building Lexical Resources from Semantically Annotated Corpora, 2004)
The IAMTC project (Interlingual Annotation of Multilingual Translation Corpora) is developing an interlingual representation frameworkfor annotation of parallel corpora (English paired with Arabic, French, Hindi, Japanese, Korean, and Spanish) with deep-semantic representations. In particular, we are investigating meaning equivalent paraphrases involving conversives and non-literal language use, as well as extended paraphrases involving syntax, lexicon, and grammatical features. The interlingua representation has three levels of depth. Each level is characterized by the types of meaning equivalent paraphrases that receive identical representations at that level.

Semantic Annotation for Interlingual Representation of Multilingual Texts - Mitamura,T.; Miller,K.; Dorr, Bonnie J; Farwell,D.; Habash,N.; Helmreich,S.; Hovy,E.; Levin,L.; Rambow,O.; Reeder,F.; others (Workshop Programme, 2004)
This paper describes the annotation process being used in a multi-site project to create six sizable bilingual parallel corpora annotated with a consistent interlingua representation. After presenting the background and objectives of the effort, we describe the multilingual corpora and the three stages of interlingual representation being developed. We then focus on the annotation process itself, including an interface environment that supports the annotation task, and the methodology for evaluating the interlingua representation. Finally, we discuss some issues encountered during the annotation tasks. The resulting annotated multilingual corpora will be useful for a wide range of natural language processing research tasks, including machine translation, question answering, text summarization, and information extraction.

Sequencing Strategies for Parasite Genomes - Bartholomeu,D.; El‐Sayed, Najib M.; Melville,S. E. (METHODS IN MOLECULAR BIOLOGY-CLIFTON THEN TOTOWA-, 2004)

Simple statistical models predict C-to-U edited sites in plant mitochondrial RNA - Cummings, Michael P.; Myers,D. S (BMC Bioinformatics, 2004)
BACKGROUND: RNA editing is the process whereby an RNA sequence is modified from the sequence of the corresponding DNA template. In the mitochondria of land plants, some cytidines are converted to uridines before translation. Despite substantial study, the molecular biological mechanism by which C-to-U RNA editing proceeds remains relatively obscure, although several experimental studies have implicated a role for cis-recognition. A highly non-random distribution of nucleotides is observed in the immediate vicinity of edited sites (within 20 nucleotides 5' and 3'), but no precise consensus motif has been identified. RESULTS: Data for analysis were derived from the the complete mitochondrial genomes of Arabidopsis thaliana, Brassica napus, and Oryza sativa; additionally, a combined data set of observations across all three genomes was generated. We selected datasets based on the 20 nucleotides 5' and the 20 nucleotides 3' of edited sites and an equivalently sized and appropriately constructed null-set of non-edited sites. We used tree-based statistical methods and random forests to generate models of C-to-U RNA editing based on the nucleotides surrounding the edited/non-edited sites and on the estimated folding energies of those regions. Tree-based statistical methods based on primary sequence data surrounding edited/non-edited sites and estimates of free energy of folding yield models with optimistic re-substitution-based estimates of approximately 0.71 accuracy, approximately 0.64 sensitivity, and approximately 0.88 specificity. Random forest analysis yielded better models and more exact performance estimates with approximately 0.74 accuracy, approximately 0.72 sensitivity, and approximately 0.81 specificity for the combined observations. CONCLUSIONS: Simple models do moderately well in predicting which cytidines will be edited to uridines, and provide the first quantitative predictive models for RNA edited sites in plant mitochondria. Our analysis shows that the identity of the nucleotide -1 to the edited C and the estimated free energy of folding for a 41 nt region surrounding the edited C are the most important variables that distinguish most edited from non-edited sites. However, the results suggest that primary sequence data and simple free energy of folding calculations alone are insufficient to make highly accurate predictions.

Skoll: distributed continuous quality assurance - Memon, Atif M.; Porter, Adam; Yilmaz,C.; Nagarajan,A.; Schmidt,D.; Natarajan,B. (Software Engineering, 2004. ICSE 2004. Proceedings. 26th International Conference on, 2004)
Quality assurance (QA) tasks, such as testing, profiling, and performance evaluation, have historically been done in-house on developer-generated workloads and regression suites. Since this approach is inadequate for many systems, tools and processes are being developed to improve software quality by increasing user participation in the QA process. A limitation of these approaches is that they focus on isolated mechanisms, not on the coordination and control policies and tools needed to make the global QA process efficient, effective, and scalable. To address these issues, we have initiated the Skoll project, which is developing and validating novel software QA processes and tools that leverage the extensive computing resources of worldwide user communities in a distributed, continuous manner to significantly and rapidly improve software quality. This paper provides several contributions to the study of distributed continuous QA. First, it illustrates the structure and functionality of a generic around-the-world, around-the-clock QA process and describes several sophisticated tools that support this process. Second, it describes several QA scenarios built using these tools and process. Finally, it presents a feasibility study applying these scenarios to a 1MLOC+ software package called ACE+TAO. While much work remains to be done, the study suggests that the Skoll process and tools effectively manage and control distributed, continuous QA processes. Using Skoll we rapidly identified problems that had taken the ACE+TAO developers substantially longer to find and several of which had previously not been found. Moreover, automatic analysis of QA task results often provided developers information that quickly led them to the root cause of the problems.
Keywords: 1MLOC+ software package; ACE+TAO; around-the-clock QA process; around-the-world QA process; distributed continuous QA; distributed continuous quality assurance; distributed programming; program verification; Quality assurance; Skoll; software performance evaluation; software profiling; Software quality; Software testing

Structural and algorithmic aspects of massive social networks - Eubank,Stephen; Kumar,V. S. Anil; Marathe,Madhav V.; Srinivasan, Aravind; Wang,Nan (Proceedings of the fifteenth annual ACM-SIAM symposium on Discrete algorithms, 2004)
We study the algorithmic and structural properties of very large, realistic social contact networks. We consider the social network for the city of Portland, Oregon, USA, developed as a part of the TRANSIMS/EpiSims project at the Los Alamos National Laboratory. The most expressive social contact network is a bipartite graph, with two types of nodes: people and locations; edges represent people visiting locations on a typical day. Three types of results are presented. (i) Our empirical results show that many basic characteristics of the dataset are well-modeled by a random graph approach suggested by Fan Chung Graham and Lincoln Lu (the CL-model), with a power-law degree distribution. (ii) We obtain fast approximation algorithms for computing basic structural properties such as clustering coefficients and shortest paths distribution. We also study the dominating set problem for such networks; this problem arose in connection with optimal sensor-placement for disease-detection. We present a fast approximation algorithm for computing near-optimal dominating sets. (iii) Given the close approximations provided by the CL-model to our original dataset and the large data-volume, we investigate fast methods for generating such random graphs. We present methods that can generate such a random network in near-linear time, and show that these variants asymptotically share many key features of the CL-model, and also match the Portland social network.The structural results have been used to study the impact of policy decisions for controlling large-scale epidemics in urban environments.

Supervised clustering with the dirichlet process - Daumé, Hal; Marcu,D. (NIPS'04 Learning With Structured Outputs Workshop, 2004)

Symbolic MT With Statistical NLP Components - Dorr, Bonnie J; Habash,Nizar Y; Monz,Christof (Instititue for Advanced Computer Studies, Univ of Maryland, College Park, 2004)
This reports provides an overview of the findings and software that have evolved from the "Symbolic MT with Statistical NLP Components" project over the last year. We present the major goals that have been achieved and discuss some of the open issues that we intend to address in the near future. This report also contains some details on the usage of some software that has been implemented during the project.
Keywords: *MACHINE TRANSLATION; computational linguistics; COMPUTER PROGRAMS; CYBERNETICS; DIVERGENCE UNRAVELING; GHMT(GENERATION-HEAVY MACHINE TRANSLATION); INFORMATION SCIENCE; linguistics; natural language; RESOURCE PROJECTION

Toolkit design for interactive structured graphics - Bederson, Benjamin B.; Grosjean,J.; Meyer,J. (Software Engineering, IEEE Transactions on, 2004)

Tools for children to create physical interactive storyrooms - Montemayor,J.; Druin, Allison; Chipman,G.; Farber,A.; Guha,M.L. (Computers in Entertainment (CIE), 2004)

A tree-position kernel for document compression - Daumé, Hal; Marcu,D. (Proceedings of the Fourth Document Understanding Conference (DUC 2004), 2004)

Trust-preserving set operations - Morselli,R.; Bhattacharjee, Bobby; Katz, Jonathan; Keleher,P. (INFOCOM 2004. Twenty-third AnnualJoint Conference of the IEEE Computer and Communications Societies, 2004)
We describe a method for performing trust-preserving set operations by untrusted parties. Our motivation for this is the problem of securely reusing content-based search results in peer-to-peer networks. We model search results and indexes as data sets. Such sets have value for answering a new query only if they are trusted. In the absence of any system-wide security mechanism, a data set is trusted by a node a only if it was generated by some node which is trusted by a. Our main contributions are a formal definition of the problem as well as an efficient scheme that solves this problem by allowing untrusted peers to perform set operations on trusted data sets while also producing unforgeable proofs of correctness. This is accomplished by requiring trusted nodes to sign appropriately-defined digests of generated sets; each such digest consists of an RSA accumulator and a Bloom filter. The scheme is general, and has other applications as well. We give an analysis demonstrating the low overhead of the scheme, and we include experimental data which confirm the analysis.
Keywords: accumulator; Bloom; computing; filter; mechanism; network; operation; peer-to-peer; RSA; Security; security; set; system-wide; Telecommunication; theory; trust-preserving

Uncalibrated stereo rectification for automatic 3D surveillance - Lim,S.-N.; Mittal,A.; Davis, Larry S.; Paragios,N. (Image Processing, 2004. ICIP '04. 2004 International Conference on, 2004)
We describe a stereo rectification method suitable for automatic 3D surveillance. We take advantage of the fact that in a typical urban scene, there is ordinarily a small number of dominant planes. Given two views of the scene, we align a dominant plane in one view with the other. Conjugate epipolar lines between the reference view and plane-aligned image become geometrically identical and can be added to the rectified image pair line by line. Selecting conjugate epipolar lines to cover the whole image is simplified since they are geometrically identical. In addition, the polarities of conjugate epipolar lines are automatically preserved by plane alignment, which simplifies stereo matching.
Keywords: 3D; AUTOMATIC; conjugate; epipolar; image; lines; matching; method; processing; rectification; scene; stereo; surveillance; uncalibrated; urban

Uncertainty in visual processes predicts geometrical optical illusions - Fermüller, Cornelia; Malm,Henrik (Vision Research, 2004)
It is proposed in this paper that many geometrical optical illusions, as well as illusory patterns due to motion signals in line drawings, are due to the statistics of visual computations. The interpretation of image patterns is preceded by a step where image features such as lines, intersections of lines, or local image movement must be derived. However, there are many sources of noise or uncertainty in the formation and processing of images, and they cause problems in the estimation of these features; in particular, they cause bias. As a result, the locations of features are perceived erroneously and the appearance of the patterns is altered. The bias occurs with any visual processing of line features; under average conditions it is not large enough to be noticeable, but illusory patterns are such that the bias is highly pronounced. Thus, the broader message of this paper is that there is a general uncertainty principle which governs the workings of vision systems, and optical illusions are an artifact of this principle.
Keywords: Bias; Estimation processes; Motion perception; NOISE; optical illusions

Use of Minimal Lexical Conceptual Structures for Single-Document Summarization - Dorr, Bonnie J; Habash,Nizar Y; Monz,Christof; Schwartz,Richard (Instititue for Advanced Computer Studies, Univ of Maryland, College Park, 2004)
This reports provides an overview of the findings and software that have evolved from the Use of Minimal Lexical Conceptual Structures for Single-Document Summarization project over the last six months. We present the major goals that have been achieved and discuss some of the open issues that we intend to address in the near future. This report also contains some details on the usage of some software that has been implemented during the project.
Keywords: *COMPUTATIONAL LINGUISTICS; AUTOMATIC HEADLINE GENERATION; CYBERNETICS; DOCUMENT SUMMARIZATION; Information retrieval; INFORMATION SCIENCE; linguistics; Machine translation

Using tasks to automate regression testing of GUIs - Memon, Atif M. (International Conference on Artificial intelligence and Applications (AIA 2004), 2004)
Graphical User Interfaces (GUIs) present unique chal-lenges for software testing. In this paper, we demonstrate that a test suite originally used to test a GUI contains a large number of unusable test cases for the modified GUI. We present a novel technique to recreate unusable test cases by associating meta-information (called a task) with each test case. Tasks represent activities that can be performed by using the software. The sequence of events in a test case represents the actions needed to complete its associated task. Even when changes to the GUI make test cases unus- able, many tasks remain valid across successive GUI ver- sions. We experimentally show that our technique is able to automatically and efficiently regenerate a large number of test cases.

Using the structure of Web sites for automatic segmentation of tables - Lerman,Kristina; Getoor, Lise; Minton,Steven; Knoblock,Craig (Proceedings of the 2004 ACM SIGMOD international conference on Management of data, 2004)
Many Web sites, especially those that dynamically generate HTML pages to display the results of a user's query, present information in the form of list or tables. Current tools that allow applications to programmatically extract this information rely heavily on user input, often in the form of labeled extracted records. The sheer size and rate of growth of the Web make any solution that relies primarily on user input is infeasible in the long term. Fortunately, many Web sites contain much explicit and implicit structure, both in layout and content, that we can exploit for the purpose of information extraction. This paper describes an approach to automatic extraction and segmentation of records from Web tables. Automatic methods do not require any user input, but rely solely on the layout and content of the Web source. Our approach relies on the common structure of many Web sites, which present information as a list or a table, with a link in each entry leading to a detail page containing additional information about that item. We describe two algorithms that use redundancies in the content of table and detail pages to aid in information extraction. The first algorithm encodes additional information provided by detail pages as constraints and finds the segmentation by solving a constraint satisfaction problem. The second algorithm uses probabilistic inference to find the record segmentation. We show how each approach can exploit the web site structure in a general, domain-independent manner, and we demonstrate the effectiveness of each algorithm on a set of twelve Web sites.

Using transient/persistent errors to develop automated test oracles for event-driven software - Memon, Atif M.; Xie,Qing (Automated Software Engineering, 2004. Proceedings. 19th International Conference on, 2004)
Today's software-intensive systems contain an important class of software, namely event-driven software (EDS). All EDS take events as input, change their state, and (perhaps) output an event sequence. EDS is typically implemented as a collection of event-handlers designed to respond to individual events. The nature of EDS creates new challenges for test automation. In this paper, we focus on those relevant to automated test oracles. A test oracle is a mechanism that determines whether a software executed correctly for a test case. A test case for an EDS consists of a sequence of events. The test case is executed on the EDS, one event at a time. Errors in the EDS may "appear" and later ”disappear" at several points (e.g., after an event is executed) during test case execution. Because of the behavior of these transient (those that disappear) and persistent (those that don't disappear) errors, EDS require complex and expensive test oracles that compare the expected and actual output multiple times during test case execution. We leverage our previous work to study several applications and observe the occurrence of persistent/transient errors. Our studies show that in practice, a large number of errors in EDS are transient and that there are specific classes of events that lead to transient errors. We use the results of this study to develop a new test oracle that compares the expected and actual output at strategic points during test case execution. We show that the oracle is effective at detecting errors and efficient in terms of resource utilization
Keywords: automated test oracles; Automatic testing; event driven software; Graphical user interfaces; persistent errors; program testing; resource allocation; resource utilization; software intensive systems; test case execution; transient errors

Using Trust in Recommender Systems: An Experimental Analysis - Massa,Paolo; Bhattacharjee, Bobby (Trust ManagementTrust Management, 2004)
Recommender systems (RS) have been used for suggesting items (movies, books, songs, etc.) that users might like. RSs compute a user similarity between users and use it as a weight for the users’ ratings. However they have many weaknesses, such as sparseness, cold start and vulnerability to attacks. We assert that these weaknesses can be alleviated using a Trust-aware system that takes into account the “web of trust” provided by every user. Specifically, we analyze data from the popular Internet web site epinions.com . The dataset consists of 49290 users who expressed reviews (with rating) on items and explicitly specified their web of trust, i.e. users whose reviews they have consistently found to be valuable. We show that any two users have usually few items rated in common. For this reason, the classic RS technique is often ineffective and is not able to compute a user similarity weight for many of the users. Instead exploiting the webs of trust, it is possible to propagate trust and infer an additional weight for other users. We show how this quantity can be computed against a larger number of users.
Keywords: Computer; Science

Validating quality of service for reusable software via model-integrated distributed continuous quality assurance - Krishna,A.; Schmidt,D.; Memon, Atif M.; Porter, Adam; Sevilla,D. (Software Reuse: Methods, Techniques, and Tools, 2004)
Quality assurance (QA) tasks, such as testing, profiling, and performance evaluation, have historically been done in-house on developer-generated workloads and regression suites. Performance-intensive systems software, such as that found in the scientific computing grid and distributed real-time and embedded (DRE) domains, increasingly run on heterogeneous combinations of OS, compiler, and hardware platforms. Such software has stringent quality of service (QoS) requirements and often provides a variety of configuration options to optimize QoS. As a result, QA performed solely in-house is inadequate since it is hard to manage software variability, i.e., ensuring software quality on all supported target platforms across all desired configuration options. This paper describes how the Skoll project is addressing these issues by developing advanced QA processes and tools that leverage the extensive computing resources of user communities in a distributed, continuous manner to improve key software quality attributes.

Variation of toxigenic Vibrio cholerae O1 in the aquatic environment of Bangladesh and its correlation with the clinical strains - Islam,M. S.; Talukder,K. A.; Khan,N. H.; Mahmud,Z. H.; Rahman,M. Z.; Nair,G. B.; Siddique,A. K. M.; Yunus,M.; Sack,D. A.; Sack,R. B.; Rita R Colwell (Microbiology and immunology, 2004)

Video-Based Automatic Target Recognition - Zhou,S. K; Chellapa, Rama; Mei,Xue; Wu,Hao; Qinfen Zheng (MARYLAND UNIV COLLEGE PARK CENTER FOR AUTOMATION RESEARCH, 2004)
We present an approach for vehicle classification in IR video sequences by integrating detection, tracking and recognition. The method has two steps. First, the moving target is automatically detected using a detection algorithm. Next, we perform simultaneous tracking and recognition using an appearance-model based particle filter. The tracking result is evaluated at each frame. Low confidence in tracking performance initiates a new cycle of detection, tracking and classification. We demonstrate the robustness of the proposed method using outdoor IR video sequences.
Keywords: *SEQUENCES(MATHEMATICS); *TARGET RECOGNITION; *VEHICLES; *VIDEO RECORDING; algorithms; AUTOMATIC TRACKING.; COMPONENT REPORTS; MOVING TARGETS; SURFACE TRANSPORTATION AND EQUIPMENT; SYMPOSIA; TARGET CLASSIFICATION; TARGET DIRECTION, RANGE AND POSITION FINDING; tracking; VIDEO SIGNALS

Visibility analysis and sensor planning in dynamic environments - Mittal,A.; Davis, Larry S. (Computer Vision-ECCV 2004, 2004)
We analyze visibility from static sensors in a dynamic scene with moving obstacles (people). Such analysis is considered in a probabilistic sense in the context of multiple sensors, so that visibility from even one sensor might be sufficient. Additionally, we analyze worst-case scenarios for high-security areas where targets are non-cooperative. Such visibility analysis provides important performance characterization of multi-camera systems. Furthermore, maximization of visibility in a given region of interest yields the optimum number and placement of cameras in the scene. Our analysis has applications in surveillance – manual or automated – and can be utilized for sensor planning in places like museums, shopping malls, subway stations and parking lots. We present several example scenes – simulated and real – for which interesting camera configurations were obtained using the formal analysis developed in the paper.

Vision Geometry XII - Latecki,L.J.; Mount, Dave; Wu,A. Y (Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 2004)

Vision geometry XII:(San Jose CA, 19-20 January 2004) - Latecki,L.J.; Mount, Dave; Wu,A. Y (SPIE proceedings series, 2004)

Visual tracking and recognition using appearance-adaptive models in particle filters - Zhou,Shaohua Kevin; Chellapa, Rama; Moghaddam, B. (IEEE Transactions on Image Processing, 2004)
We present an approach that incorporates appearance-adaptive models in a particle filter to realize robust visual tracking and recognition algorithms. Tracking needs modeling interframe motion and appearance changes, whereas recognition needs modeling appearance changes between frames and gallery images. In conventional tracking algorithms, the appearance model is either fixed or rapidly changing, and the motion model is simply a random walk with fixed noise variance. Also, the number of particles is typically fixed. All these factors make the visual tracker unstable. To stabilize the tracker, we propose the following modifications: an observation model arising from an adaptive appearance model, an adaptive velocity motion model with adaptive noise variance, and an adaptive number of particles. The adaptive-velocity model is derived using a first-order linear predictor based on the appearance difference between the incoming observation and the previous particle configuration. Occlusion analysis is implemented using robust statistics. Experimental results on tracking visual objects in long outdoor and indoor video sequences demonstrate the effectiveness and robustness of our tracking algorithm. We then perform simultaneous tracking and recognition by embedding them in a particle filter. For recognition purposes, we model the appearance changes between frames and gallery images by constructing the intra- and extrapersonal spaces. Accurate recognition is achieved when confronted by pose and view variations.
Keywords: adaptive filters; adaptive noise variance; algorithms; appearance-adaptive model; Artificial intelligence; Cluster Analysis; Computer Graphics; Computer simulation; Feedback; Filtering; first-order linear predictor; hidden feature removal; HUMANS; Image Enhancement; Image Interpretation, Computer-Assisted; image recognition; Information Storage and Retrieval; Kinematics; Laboratories; Male; Models, Biological; Models, Statistical; MOTION; Movement; Noise robustness; Numerical Analysis, Computer-Assisted; occlusion analysis; Particle filters; Particle tracking; Pattern Recognition, Automated; Predictive models; Reproducibility of results; robust statistics; Sensitivity and Specificity; Signal Processing, Computer-Assisted; State estimation; statistical analysis; Subtraction Technique; tracking; Training data; visual recognition; visual tracking

Whole-genome shotgun assembly and comparison of human genome assemblies - Istrail,S.; Sutton,G. G; Florea,L.; Halpern,A. L; Mobarry,C. M; Lippert,R.; Walenz,B.; Shatkay,H.; Dew,I.; Miller,J. R; others (Proceedings of the National Academy of Sciences of the United States of America, 2004)

Word Level Script Identification on Scanned Document Images - Ma,Huanfeng; David Doermann (SPIEConference on Document Recognition and Retrieval, 2004)

2003 IEEE Workshop on Applications of Signal Processing to Audio and Acoustics October 19-22, 2003, New Paltz. NY - Adams,N.; EssI,G.; Makino,S.; Martens,A.A.C.F.W.L.; Algazi,R.; Fellers,M.; Martin,R.; Avendano,C.; Fielder,L.; Mellody,M.; others (2003 IEEE Workshop on Applications of Signal Processing to Audio and Acoustics: October 19-22, 2003, Mohonk Mountain House, New Paltz, NY, USA, 2003)

A 4-Year Study of the Epidemiology of Vibrio Cholerae in Four Rural Areas of Bangladesh - Sack,R. Bradley; Siddique,A. Kasem; Longini,Ira M.; Nizam,Azhar; Yunus,Md; M. Sirajul Islam; Morris,Jr; Ali,Afsar; Huq,Anwar; Nair,G. Balakrish; Qadri,Firdausi; Faruque,Shah M.; et al. (Journal of Infectious DiseasesJ Infect Dis., 2003)
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

Adaptive Hindi OCRUsing Generalized Hausdorff Image Comparison - Ma,Huanfeng; David Doermann (University of Maryland, College Park, 2003)
In this paper, we present an adaptive Hindi OCR using generalized Hausdor image comparison implemented as part of a rapidly retargetable language tool effort. The system includes: script identification, character segmentation, training sample creation and character recognition. The OCR design (completed in one month) was applied to a complete Hindi-English bilingual dictionary (with 1083 pages) and a collection of ideal images extracted from Hindi documents in PDF format. Experimental results show the recognition accuracy can reach 88% for noisy images and 95% for ideal images, both at the character level. The presented method can also be extended to design OCR systems for different scripts.

Adaptive visual tracking and recognition using particle filters - Zhou,Shaohua; Chellapa, Rama; Moghaddam, B. (Multimedia and Expo, 2003. ICME '03. Proceedings. 2003 International Conference on, 2003)
This paper presents an improved method for simultaneous tracking and recognition of human faces from video, where a time series model is used to resolve the uncertainties in tracking and recognition. The improvements mainly arise from three aspects: (i) modeling the inter-frame appearance changes within the video sequence using an adaptive appearance model and an adaptive-velocity motion model; (ii) modeling the appearance changes between the video frames and gallery images by constructing intra- and extra-personal spaces; and (iii) utilization of the fact that the gallery images are in frontal views. By embedding them in a particle filter, we are able to achieve a stabilized tracker and an accurate recognizer when confronted by pose and illumination variations.
Keywords: adaptive; adaptive-velocity; appearance; extra-personal; Filtering; filters; image; intra-personal; model; MOTION; particle; processing; recognition; sequence; sequences; series; signal; spaces; theory; TIME; tracking; video; visual

Advances in GUI Testing - Memon, Atif M. (Advances in ComputersAdvances in Computers, 2003)
Graphical user interfaces are by far the most popular means used to interact with software today. Unfortunately, the state-of-the-practice in GUI testing has not kept pace with the rapidly evolving GUI technology. In practice, GUI testing is largely manual, often resulting in inadequate testing. There have been several research efforts to improve GUI testing. This chapter presents some of the recent advances in GUI testing and provides guidelines on how to combine them.

Advances in GUI Testing-10 Summary - Memon, Atif M. (Advances in Computers, 2003)

Advances in GUI Testing-2 GUI Testing Steps - Memon, Atif M. (Advances in Computers, 2003)

Advances in GUI Testing-3 Record/Playback Tools - Memon, Atif M. (Advances in Computers, 2003)

Advances in GUI Testing-4 Challenges - Memon, Atif M. (Advances in Computers, 2003)

Advances in GUI Testing-5 State Machine Models - Memon, Atif M. (Advances in Computers, 2003)

Advances in GUI Testing-6 Behavioral Models - Memon, Atif M. (Advances in Computers, 2003)

Advances in GUI Testing-7 Statistical Methods - Memon, Atif M. (Advances in Computers, 2003)

Advances in GUI Testing-8 Hierarchical Techniques - Memon, Atif M. (Advances in Computers, 2003)

Advances in GUI Testing-9 Discussion - Memon, Atif M. (Advances in Computers, 2003)

An Analysis of the Layer 2 Handoff costs in Wireless Local Area Networks - Mishra,A.; Shin,M. H.; Arbaugh, William A. (ACM Computer Communications Review, 2003)

Augmented intelligibility in simultaneous multi-talker environments - Mesgarani,N.; Shamma,S.; Grant,K.W.; Duraiswami, Ramani (Proc. International Conference on Auditory Display (ICAD’03), 2003)
Speech intelligibility can be severely compromised inenvironments where there are several competing speakers. It may be possible, however, to improve speech intelligibility in such environments by manipulating certain acoustic parameters known to facilitate the segregation of competing signals. The first step in designing such a feature-rich audio display is to understand the significant elements of human auditory perception that affect information transmission capacity. We review a series of experiments to examine the impact of different audio-display design parameters on overall intelligibility of simultaneous speech messages and show how using these features may improve intelligibility.

Automating DAML-S Web Services Composition Using SHOP2 - Wu,Dan; Parsia,Bijan; Sirin,Evren; Hendler,James; Nau, Dana S. (The Semantic Web - ISWC 2003, 2003)
The DAML-S Process Model is designed to support the application of AI planning techniques to the automated composition of Web services. SHOP2 is an Hierarchical Task Network (HTN) planner well-suited for working with the Process Model. We have proven the correspondence between the semantics of SHOP2 and the situation calculus semantics of the Process Model. We have also implemented a system which soundly and completely plans over sets of DAML-S descriptions using a SHOP2 planner, and then executes the resulting plans over the Web. We discuss the challenges and difficulties of using SHOP2 in the information-rich and human-oriented context of Web services.
Keywords: Computer science

Bringing Treasures to the Surface: Previews and Overviews in a Prototype for the Library of Congress National Digital Library - Marchionini,A.S.; Nation,D.; Karasik,S.; Cronnell,T.; Shneiderman, Ben; Spotfire,V.D.M.U.; Bederson, Benjamin B.; Data,T.S.; Hochheiser,H.; Shneiderman, Ben; others (The craft of information visualization: readings and reflections, 2003)

Comparing bootstrap and posterior probability values in the four-taxon case - Cummings, Michael P.; Handley,S. A; Myers,D. S; Reed,D. L; Rokas,A.; Winka,K. (Syst Biol, 2003)
Assessment of the reliability of a given phylogenetic hypothesis is an important step in phylogenetic analysis. Historically, the nonparametric bootstrap procedure has been the most frequently used method for assessing the support for specific phylogenetic relationships. The recent employment of Bayesian methods for phylogenetic inference problems has resulted in clade support being expressed in terms of posterior probabilities. We used simulated data and the four-taxon case to explore the relationship between nonparametric bootstrap values (as inferred by maximum likelihood) and posterior probabilities (as inferred by Bayesian analysis). The results suggest a complex association between the two measures. Three general regions of tree space can be identified: (1) the neutral zone, where differences between mean bootstrap and mean posterior probability values are not significant, (2) near the two-branch corner, and (3) deep in the two-branch corner. In the last two regions, significant differences occur between mean bootstrap and mean posterior probability values. Whether bootstrap or posterior probability values are higher depends on the data in support of alternative topologies. Examination of star topologies revealed that both bootstrap and posterior probability values differ significantly from theoretical expectations; in particular, there are more posterior probability values in the range 0.85-1 than expected by theory. Therefore, our results corroborate the findings of others that posterior probability values are excessively high. Our results also suggest that extrapolations from single topology branch-length studies are unlikely to provide any general conclusions regarding the relationship between bootstrap and posterior probability values.

Critical fields and pulse durations for precessional switching of thin magnetic films - Bertotti,G.; Mayergoyz, Issak D; Serpico,C. (Magnetics, IEEE Transactions on, 2003)
The precessional switching process of a uniformly magnetized thin film with in-plane anisotropy subject to pulsed magnetic fields applied in the film plane is analyzed. Critical fields required to achieve switching are studied for the case when the applied field is constant during the pulse duration and forms arbitrary angles with the hard axis. By using two integrals of magnetization motion, the explicit expressions for the critical field are derived. The formulas for durations of rectangular magnetic field pulses that guarantee the precessional switching of magnetization are presented as well.
Keywords: anisotropy; axis; critical; durations; field; fields; film; films; hard; in-plane; integrals; magnetic; magnetisation; magnetization; magnetization; magnetized; motion; precessional; pulse; pulsed; rectangular; reversal; switching; thin; uniformly

DART: a framework for regression testing "nightly/daily builds" of GUI applications - Memon, Atif M.; Banerjee,I.; Hashmi,N.; Nagarajan,A. (Software Maintenance, 2003. ICSM 2003. Proceedings. International Conference on, 2003)
"Nightly/daily building and smoke testing" have become widespread since they often reveal bugs early in the software development process. During these builds, software is compiled, linked, and (re)tested with the goal of validating its basic functionality. Although successful for conventional software, smoke tests are difficult to develop and automatically rerun for software that has a graphical user interface (GUI). In this paper, we describe a framework called DART (daily automated regression tester) that addresses the needs of frequent and automated re-testing of GUI software. The key to our success is automation: DART automates everything from structural GUI analysis; test case generation; test oracle creation; to code instrumentation; test execution; coverage evaluation; regeneration of test cases; and their re-execution. Together with the operating system's task scheduler, DART can execute frequently with little input from the developer/tester to retest the GUI software. We provide results of experiments showing the time taken and memory required for GUI analysis, test case and test oracle generation, and test execution. We also empirically compare the relative costs of employing different levels of detail in the GUI test cases.
Keywords: automated retesting; automatic test software; coverage evaluation; daily automated regression tester; DART; frequent retesting; graphical user interface; Graphical user interfaces; GUI software; instrumentation coding; program testing; regression testing; Software development management; Software development process; Software maintenance; Software quality; structural GUI analysis; Test Case Generation; test cases regeneration; Test execution; test oracle creation

Data Structures and Algorithms in C++ - Goodrich, Michael T.; Tamassia, Roberto; Mount, Dave (John Wiley & Sons, 2003)
* Provides a comprehensive introduction to data structures and algorithms, including their design, analysis, and implementation * Each data structure is presented using ADTs and their respective implementations * Helps provide an understanding of the wide spectrum of skills ranging from sound algorithm and data structure design to efficient implementation and coding of these designs in C++
Keywords: Computers / Databases / General; Computers / Programming / Algorithms; Computers / Programming / General; Computers / Programming Languages / C; Fiction / General

Data structures for 3D Multi-Tessellations: an overview - Danovaro,E.; De Floriani, Leila; Magillo,P.; Puppo,E. (Data Visualization: The State of the ArtData Visualization: The State of the Art, 2003)

Decomposing non-manifold objects in arbitrary dimensions - De Floriani, Leila; Mesmoudi,Mostefa M.; Morando,Franco; Puppo,Enrico (Graphical Models, 2003)
We address the problem of building valid representations of non-manifold d-dimensional objects through an approach based on decomposing a non-manifold d-dimensional object into an assembly of more regular components. We first define a standard decomposition of d-dimensional non-manifold objects described by abstract simplicial complexes. This decomposition splits a non-manifold object into components that belong to a well-understood class of objects, that we call initial quasi-manifold. Initial quasi-manifolds cannot be decomposed without cutting them along manifold faces. They form a decidable superset of d-manifolds for d⩾3, and coincide with manifolds for d⩽2. We then present an algorithm that computes the standard decomposition of a general non-manifold complex. This decomposition is unique, and removes all singularities which can be removed without cutting the complex along its manifold faces.

Digital government - Marchionini,G.; Samet, Hanan; Brandt,L. (Communications of the ACM, 2003)
Information technologies are being applied vigorously by governmental units at national,regional, and local levels around the world. The application of IT to government service is often termed “e-government” and the larger concept of government that depends upon IT to achieve basic missions is termed “digital government.” This distinction is, of course, lexically arbitrary, but serves to distinguish R&D specifically aimed at creating techniques for applying IT to government operations. Such R&D efforts also consider the long-term impact of these applications on citizens and government itself.

Driving scientific applications by data in distributed environments - Saltz, J.; Catalyurek,U.; Kurc, T.; Gray,M.; Hastings,S.; Langella,S.; Narayanan,S.; Martino,R.; Bryant,S.; Peszynska,M.; others (Computational Science—ICCS 2003, 2003)

Dynamic load balancing across mirrored multimedia servers - Matthur,A.; Mundur, Padma (2003 International Conference on Multimedia and Expo, 2003. ICME '03. Proceedings, 2003)
The purpose of this paper is to present protocols for efficient load balancing across replicated multimedia servers in a metropolitan area network. Current multimedia infrastructures, even when they use mirrored servers, do not have standardized load balancing schemes. Existing schemes frequently require participation from the clients in balancing the load across the servers efficiently. We propose two protocols in this paper for fair load balancing without any client-side processing being required. Neither protocol requires any change to the network-level infrastructure. Using network packet loss and packet transmission delay as the chief metrics, we show the effectiveness of the protocols through extensive simulations.
Keywords: client-server systems; Delay; Internet; load balancing protocols; Load management; media streaming; metropolitan area network; metropolitan area networks; mirrored multimedia servers; Multimedia communication; multimedia servers; network packet loss; Network servers; packet transmission delay; Propagation losses; Protocols; Streaming media; Topology; Traffic control; Web server

Dynamic querying for pattern identification in microarray and genomic data - Hochheiser,H.; Baehrecke,E. H; Mount, Stephen M.; Shneiderman, Ben (2003 International Conference on Multimedia and Expo, 2003. ICME '03. Proceedings, 2003)
Data sets involving linear ordered sequences are a recurring theme in bioinformatics. Dynamic query tools that support exploration of these data sets can be useful for identifying patterns of interest. This paper describes the use of one such tool - timesearcher - to interactively explore linear sequence data sets taken from two bioinformatics problems. Microarray time course data sets involve expression levels for large numbers of genes over multiple time points. Timesearcher can be used to interactively search these data sets for genes with expression profiles of interest. The occurrence frequencies of short sequences of DNA in aligned exons can be used to identify sequences that play a role in the pre-mRNA splicing. Timesearcher can be used to search these data sets for candidate splicing signals.
Keywords: Bioinformatics; data sets; Displays; dynamic querying; expression profiles; Frequency; Gene expression; genes; Genetics; genomic data; Genomics; linear ordered sequences; macromolecules; medical signal processing; Mice; Microarray; pattern identification; pattern recognition; premRNA splicing; Query processing; sequences; Signal processing; splicing; TimeSearcher

Energy-efficient broadcast and multicast trees for reliable wireless communication - Banerjee,S.; Misra,A.; Yeo,Jihwang; Agrawala, Ashok K. (Wireless Communications and Networking, 2003. WCNC 2003. 2003 IEEE, 2003)
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.
Keywords: broadcast; channels; multicast; communication; broadcast; communication; network; data; delivery; energy-efficient; layer; multicast; network; networks; network; networks; telecommunication; paths; multicast; rates; link; reliability; topologies; wireless; topology; radio; trees; error; trees; multihop; wireless

Exploratory studies of turbulence/chemistry interaction in hypersonic flows - Martin, M.P (36 th AIAA Thermophysics Conference, 2003)

A Fast Implementation of the ISOCLUS Algorithm - Memarsadeghi,Nargess; Mount, Dave; Netanyahu,Nathan S.; LeMoigne,Jacqueline (IEEE 2003 International Geoscience and Remote Sensing Symposium, 2003)
Unsupervised clustering is a fundamental building block in numerous image processing applications. One of the most popular and widely used clustering schemes for remote sensing applications is the ISOCLUS algorithm, which is based on the ISODATA method. The algorithm is given a set of n data points in d-dimensional space, an integer k indicating the initial number of clusters, and a number of additional parameters. The general goal is to compute the coordinates of a set of cluster centers in d-space, such that those centers minimize the mean squared distance from each data point to its nearest center. This clustering algorithm is similar to another well-known clustering method, called k-means. One significant feature of ISOCLUS over k-means is that the actual number of clusters reported might be fewer or more than the number supplied as part of the input. The algorithm uses different heuristics to determine whether to merge lor split clusters. As ISOCLUS can run very slowly, particularly on large data sets, there has been a growing .interest in the remote sensing community in computing it efficiently. We have developed a faster implementation of the ISOCLUS algorithm. Our improvement is based on a recent acceleration to the k-means algorithm of Kanungo, et al. They showed that, by using a kd-tree data structure for storing the data, it is possible to reduce the running time of k-means. We have adapted this method for the ISOCLUS algorithm, and we show that it is possible to achieve essentially the same results as ISOCLUS on large data sets, but with significantly lower running times. This adaptation involves computing a number of cluster statistics that are needed for ISOCLUS but not for k-means. Both the k-means and ISOCLUS algorithms are based on iterative schemes, in which nearest neighbors are calculated until some convergence criterion is satisfied. Each iteration requires that the nearest center for each data point be computed. Naively, this requires O(kn) time, where k denotes the current number of centers. Traditional techniques for accelerating nearest neighbor searching involve storing the k centers in a data structure. However, because of the iterative nature of the algorithm, this data structure would need to be rebuilt with each new iteration. Our approach is to store the data points in a kd-tree data structure. The assignment of points to nearest neighbors is carried out by a filtering process, which successively eliminates centers that can not possibly be the nearest neighbor for a given region of space. This algorithm is significantly faster, because large groups of data points can be assigned to their nearest center in a single operation. Preliminary results on a number of real Landsat datasets show that our revised ISOCLUS-like scheme runs about twice as fast.
Keywords: algorithms; Cluster Analysis; Data structures; HEURISTIC METHODS; IMAGE PROCESSING; INTEGERS; LANDSAT SATELLITES; MEAN SQUARE VALUES; Remote sensing

Gabor Filter Based Multi-class Classifier for Scanned Document Images - Ma,H.; David Doermann (7th International Conference on Document Analysis and Recognition (ICDAR), 2003)
When scanning documents with a large number of pagessuch as books, it is often feasible to provide a minimal number of training samples to personalize the system to compensate for global shifts in how the document was created or in scanning parameters. In this paper, we present a supervised multi-class classifier based on Gabor filters that is used to classify the scripts, font-faces, and font-styles (bold, italic, normal etc.) in an application where the classes are known. Classification is performed at the word level (glyphs separated by white space) given training samples of each class. This method was applied to a variety of bilingual dictionaries to identify different scripts, and simultaneously, to classify Roman scripts into bold, italic and normal font-styles. Experimental results show the effectiveness of this approach in increasing performance over classifiers trained for general documents.

The genome sequence of Bacillus anthracis Ames and comparison to closely related bacteria - Read,Timothy D.; Peterson,Scott N.; Tourasse,Nicolas; Baillie,Les W.; Paulsen,Ian T.; Nelson,Karen E.; Tettelin,Herv|[eacute]|; Fouts,Derrick E.; Eisen,Jonathan A.; Gill,Steven R.; Holtzapple,Erik K.; |[Oslash]|kstad,Ole Andreas; et al. (Nature, 2003)
Bacillus anthracis is an endospore-forming bacterium that causes inhalational anthrax1. Key virulence genes are found on plasmids (extra-chromosomal, circular, double-stranded DNA molecules) pXO1 (ref. 2) and pXO2 (ref. 3). To identify additional genes that might contribute to virulence, we analysed the complete sequence of the chromosome of B. anthracis Ames (about 5.23 megabases). We found several chromosomally encoded proteins that may contribute to pathogenicity—including haemolysins, phospholipases and iron acquisition functions—and identified numerous surface proteins that might be important targets for vaccines and drugs. Almost all these putative chromosomal virulence and surface proteins have homologues in Bacillus cereus, highlighting the similarity of B. anthracis to near-neighbours that are not associated with anthrax4. By performing a comparative genome hybridization of 19 B. cereus and Bacillus thuringiensis strains against a B. anthracis DNA microarray, we confirmed the general similarity of chromosomal genes among this group of close relatives. However, we found that the gene sequences of pXO1 and pXO2 were more variable between strains, suggesting plasmid mobility in the group. The complete sequence of B. anthracis is a step towards a better understanding of anthrax pathogenesis.

Geometrical analysis of precessional switching and relaxation in uniformly magnetized bodies - Bertotti,G.; Mayergoyz, Issak D; Serpico,C.; d'Aquino,M. (Magnetics, IEEE Transactions on, 2003)
Precessional switching and relaxation in a single-domain particle or film is studied by using the Landau-Lifshitz-Gilbert equation. The analysis of the switching process is based on the explicit knowledge of two integrals of motion for the magnetization dynamics in the conservative case. The knowledge of these integrals of motions enables one to carry out the geometrical analysis of the system and give the complete phase portrait. The relaxation process which occurs after the magnetization is reversed is analyzed by using geometrical methods and it is showed that the dynamical system exhibits entanglement of separatrices and riddled basins of attraction.
Keywords: analysis; attraction; basins; bodies; dynamical; dynamics; entanglement; equation; film; films; geometrical; integrals; Landau-Lifshitz-Gilbert; magnetic; magnetisation; magnetization; magnetized; motion; of; particle; particles; phase; portrait; precessional; relaxation; reversal; riddled; separatrices; single-domain; spin; switching; system; thin; uniformly

GUI ripping: Reverse engineering of graphical user interfaces for testing - Memon, Atif M.; Banerjee,I.; Nagarajan,A. (Proceedings of the 10th working conference on reverse engineering (WCRE’03), 2003)
Graphical user interfaces (GUIs) are important parts oftoday’s software and their correct execution is required to ensure the correctness of the overall software. A popular technique to detect defects in GUIs is to test them by exe- cuting test cases and checking the execution results. Test cases may either be created manually or generated auto- matically from a model of the GUI. While manual testing is unacceptably slow for many applications, our experience with GUI testing has shown that creating a model that can be used for automated test case generation is difficult. We describe a new approach to reverse engineer a model represented as structures called a GUI forest, event-flow graphs and an integration tree directly from the executable GUI. We describe “GUI Ripping”, a dynamic process in which the software’s GUI is automatically “traversed” by opening all its windows and extracting all their widgets (GUI objects), properties, and values. The extracted infor- mation is then verified by the test designer and used to auto- matically generate test cases. We present algorithms for the ripping process and describe their implementation in a tool suite that operates on Java and Microsoft Windows’ GUIs. We present results of case studies which show that our approach requires very little human intervention and is es- pecially useful for regression testing of software that is mod- ified frequently. We have successfully used the “GUI Rip- per” in several large experiments and have made it avail- able as a downloadable tool.

HCIL Technical Report Listing (1993-2002) - Ceaparu,I.; Druin, Allison; Guimbretiere,F.; Manipulation,D.; Shneiderman, Ben; Westerlurid,B.; Keogh,E.; Hochheiser,H.; Shrieidemian,B.; Shneidemiari,B.; others (The craft of information visualization: readings and reflections, 2003)

Human body pose estimation using silhouette shape analysis - Mittal,A.; Liang Zhao; Davis, Larry S. (Proceedings. IEEE Conference on Advanced Video and Signal Based Surveillance, 2003., 2003)
We describe a system for human body pose estimation from multiple views that is fast and completely automatic. The algorithm works in the presence of multiple people by decoupling the problems of pose estimation of different people. The pose is estimated based on a likelihood function that integrates information from multiple views and thus obtains a globally optimal solution. Other characteristics that make our method more general than previous work include: (1) no manual initialization; (2) no specification of the dimensions of the 3D structure; (3) no reliance on some learned poses or patterns of activity; (4) insensitivity to edges and clutter in the background and within the foreground. The algorithm has applications in surveillance and promising results have been obtained.
Keywords: 3D; analysis; body; classification; clutter; detection; estimation; extraction; feature; function; human; image; likelihood; multiple; object; parameter; parameters; Pixel; pose; probability; segmentation; segmentations; SHAPE; silhouette; structure; surveillance; views

Human visual model for data hiding - M. Wu; Yu,Hong Heather (2003)
A method and apparatus of hiding identification data in visual media. When image or video data is received, frequency masking is performed to divide the image or video data into blocks of smooth regions and blocks of non-smooth regions and to obtain preliminary just-noticeable-difference. Edge detection is performed to divide the non-smooth region of the image or video data into texture blocks and edge blocks. Then blocks of regions that are substantially proximate to blocks of smooth regions of the image or video data are determined. The image or video data is then adjusted by applying different strength of watermark in association with the type of each block.

IMPACTing SHOP: Putting an AI Planner Into a Multi-Agent Environment - Dix,Jürgen; Muñoz-Avila,Héctor; Nau, Dana S.; Zhang,Lingling (Annals of Mathematics and Artificial Intelligence, 2003)
In this paper we describe a formalism for integrating the SHOP HTN planning system with the IMPACT multi-agent environment. We define the A-SHOP algorithm, an agentized adaptation of the SHOP planning algorithm that takes advantage of IMPACT's capabilities for interacting with external agents, performing mixed symbolic/numeric computations, and making queries to distributed, heterogeneous information sources (such as arbitrary legacy and/or specialized data structures or external databases). We show that A-SHOP is both sound and complete if certain conditions are met.
Keywords: Computer science

Improving the Arabidopsis genome annotation using maximal transcript alignment assemblies - Haas,Brian J.; Delcher,Arthur L.; Mount, Stephen M.; Wortman,Jennifer R.; Jr,Roger K. Smith; Hannick,Linda I.; Maiti,Rama; Ronning,Catherine M.; Rusch,Douglas B; Town,Christopher D.; Salzberg,Steven L.; White,Owen (Nucleic Acids ResearchNucl. Acids Res., 2003)
The spliced alignment of expressed sequence data to genomic sequence has proven a key tool in the comprehensive annotation of genes in eukaryotic genomes. A novel algorithm was developed to assemble clusters of overlapping transcript alignments (ESTs and full‐length cDNAs) into maximal alignment assemblies, thereby comprehensively incorporating all available transcript data and capturing subtle splicing variations. Complete and partial gene structures identified by this method were used to improve The Institute for Genomic Research Arabidopsis genome annotation (TIGR release v.4.0). The alignment assemblies permitted the automated modeling of several novel genes and >1000 alternative splicing variations as well as updates (including UTR annotations) to nearly half of the ∼27 000 annotated protein coding genes. The algorithm of the Program to Assemble Spliced Alignments (PASA) tool is described, as well as the results of automated updates to Arabidopsis gene annotations.

In Memoriam: Raymond Reiter - Minker, Jack (AI Magazine, 2003)

Innovating the Interaction - Bederson, Benjamin B.; Plaisant, Catherine; Mushlin,R.; Snyder,A.; Li,J.; Heller,D.; Shneiderman, Ben; Hochheiser,H.; Fekete,J. D; Czenvinski,M. (The craft of information visualization: readings and reflectionsThe craft of information visualization: readings and reflections, 2003)

Interactive Visualization of Large Tetrahedral Meshes through Selective Refinement - Cignoni,P.; De Floriani, Leila; Magillo,P.; Puppo,E.; Scopigno,R.; di Genova,U. (IEEE Transactions on Visualization and Computer Graphics, 2003)
In this paper, we address the problem of the efficient visualization of very largeirregular volume datasets. To this aim, we exploit a multiresolution representation based on a domain decomposition into tetrahedral cells. A new compact data struc- ture is described which encodes the whole dataset at a virtually continuous range of different resolutions, with a storage cost six times lower than a standard data struc- ture for tetrahedral meshes. Such structure supports on-line selective refinement to focus resolution on areas that the user considers more critical, based on either field values, or domain location, or opacity of the transfer function. Selective refinement is used to trade-off between resolution and speed in visualization, according to user needs and hardware constraints. These features have been implemented in a new system, called TAn2 (Tetrahedra Analyzer), for the interactive visualization of three- dimensional scalar fields defined on very large tetrahedral meshes. Multiresolution representation and selective refinement make the system fully scalable with respect to the size of the dataset and to hardware requirements.

Interpolation over light fields with applications in computer graphics - Atalay,F. B; Mount, Dave (Proceedings of the Fifth Workshop on Algorithm Engineering and Experiments, 2003)

Intrusion-resilient public-key encryption - Dodis,Y.; Franklin,M.; Katz, Jonathan; Miyaji,A.; Yung,M. (Topics in Cryptology—CT-RSA 2003, 2003)
Exposure of secret keys seems to be inevitable, and may in practice represent the most likely point of failure in a cryptographic system. Recently, the notion of intrusion-resilience [17] (which extends both the notions of forward security [3], [5] and key insulation [11]) was proposed as a means of mitigating the harmful effects that key exposure can have. In this model, time is divided into distinct periods; the public key remains fixed throughout the lifetime of the protocol but the secret key is periodically updated. Secret information is stored by both a user and a base; the user performs all cryptographic operations during a given time period, while the base helps the user periodically update his key. Intrusion-resilient schemes remain secure in the face of multiple compromises of both the user and the base, as long as they are not both compromised simultaneously. Furthermore, in case the user and base are compromised simultaneously, prior time periods remain secure (as in forward-secure schemes). Intrusion-resilient signature schemes have been previously constructed [17], [15]. Here, we give the first construction of an intrusion-resilient publickey encryption scheme, based on the recently-constructed forwardsecure encryption scheme of [8]. We also consider generic transformations for securing intrusion-resilient encryption schemes against chosenciphertext attacks.

LifeLines: Using Visualization to Enhance Navigation and Analysis of Patient Records - Plaisant, Catherine; Mushlin,Richard; Snyder,Aaron; Li,Jia; Heller,Dan; Shneiderman, Ben (The Craft of Information VisualizationThe Craft of Information Visualization, 2003)

M 2 Tracker: a multi-view approach to segmenting and tracking people in a cluttered scene - Mittal,A.; Davis, Larry S. (International Journal of Computer Vision, 2003)
When occlusion is minimal, a single camera is generally sufficient to detect and track objects. However, when the density of objects is high, the resulting occlusion and lack of visibility suggests the use of multiple cameras and collaboration between them so that an object is detected using information available from all the cameras in the scene.In this paper, we present a system that is capable of segmenting, detecting and tracking multiple people in a cluttered scene using multiple synchronized surveillance cameras located far from each other. The system is fully automatic, and takes decisions about object detection and tracking using evidence collected from many pairs of cameras. Innovations that help us tackle the problem include a region-based stereo algorithm capable of finding 3D points inside an object knowing only the projections of the object (as a whole) in two views, a segmentation algorithm using bayesian classification and the use of occlusion analysis to combine evidence from different camera pairs. The system has been tested using different densities of people in the scene. This helps us determine the number of cameras required for a particular density of people. Experiments have also been conducted to verify and quantify the efficacy of the occlusion analysis scheme.

Mathematical Models of Hysteresis and Their Applications: Second Edition - Mayergoyz, Issak D (Academic Press, 2003)
This new edition has been significantly revised and updated to reflect advances in the field since the publication of the first edition, such as the systematic experimental testing of Preisach models of hysteresis. The author has, however, retained the two most salient features of the original, the emphasis on the universal nature of mathematical models of hysteresis and their applicability to the description of hysteresis phenomena in various areas of science, technology and economics and its accessibility to a broad audience of researchers, engineers, and students. Provides a unique emphasis on the development of universal mathematical models of hysteresis Accessibility to a broad audience, using simple and complex mathematical tools, application to various areas of science. Presents new theoretical and experimental results
Keywords: Business & Economics / Industrial Management; Hysteresis; Mathematics / Applied; Mathematics / General; Science / Physics / Magnetism; Science / Physics / Mathematical & Computational; Technology & Engineering / Electrical; Technology & Engineering / Electronics / General; Technology & Engineering / Electronics / Microelectronics; Technology & Engineering / Signals & Signal Processing

Mathematical models of hysterisis and their applications (2003) - Mayergoyz, Issak D (Recherche, 2003)
This new edition has been significantly revised and updated to reflect advances in the field since the publication of the first edition, such as the systematic experimental testing of Preisach models of hysteresis. The author has, however, retained the two most salient features of the original, the emphasis on the universal nature of mathematical models of hysteresis and their applicability to the description of hysteresis phenomena in various areas of science, technology and economics and its accessibility to a broad audience of researchers, engineers, and students

Matrix Algorithms, Volume II: Eigensystems - Stewart, G.W.; Author; Mahajan,A.; Reviewer (Applied Mechanics Reviews, 2003)
Keywords: algorithm theory; Eigenvalues and eigenfunctions; linear algebra; matrix algebra; reviews

Morphology-driven simplification and multiresolution modeling of terrains - Danovaro,Emanuele; De Floriani, Leila; Magillo,Paola; Mesmoudi,Mohammed Mostefa; Puppo,Enrico (Proceedings of the 11th ACM international symposium on Advances in geographic information systems, 2003)
We propose a technique for simplification and multiresolution modeling of a terrain represented as a TIN. Our goal is to maintain the morphological structure of the terrain in the resulting multiresolution model. To this aim, we extend Morse theory, developed for continuous and differentiable functions, to the case of piecewise linear functions. We decompose a TIN into areas with uniform morphological properties (such as valleys, basins, etc.) separated by a network of critical lines and points. We describe an algorithm to compute the above decomposition and the critical net, and a TIN simplification algorithm that preserves them. On this basis, we build a multiresolution terrain model, which provides a representation of critical features at any level of detail.
Keywords: morphological structure; Multi-resolution; terrain models

Necessity is the mother of invention: a simple grid computing system using commodity tools - Myers,D. S; Cummings, Michael P. (J Parallel Distr Com, 2003)
Access to sufficient resources is a barrier to scientific progress for many researchers facing large computational problems. Gaining access to large-scale resources (i.e., university-wide or federally supported computer centers) can be difficult, given their limited availability, particular architectures, and request/review/approval cycles. Simultaneously, researchers often find themselves with access to workstations and older clusters overlooked by their owners in favor of newer hardware. Software to tie these resources into a coherent Grid, however, has been problematic. Here, we describe our experiences building a Grid computing system to conduct a large-scale simulation study using "borrowed" computing resources distributed over a wide area. Using standard software components, we have produced a Grid computing system capable of coupling several hundred processors spanning multiple continents and administrative domains. We believe that this system fills an important niche between a closely coupled local system and a heavyweight, highly customized wide area system. (C) 2003 Elsevier Science (USA). All rights reserved.
Keywords: Apache; computing; distributed; Grid; HTTP; Java; Linux; Perl; SQL; Unix; XML-RPC

On-chip stochastic communication [SoC applications] - Tudor Dumitras; Marculescu, R. (Design, Automation and Test in Europe Conference and Exhibition, 2003, 2003)
As CMOS technology scales down into the deep-submicron (DSM) domain, the costs of design and verification for systems-on-chip (SoCs) are rapidly increasing due to the inefficiency of traditional CAD tools. Relaxing the requirement of 100% correctness for devices and interconnects drastically reduces the costs of design but, at the same time, requires that SoCs be designed with some system-level fault-tolerance. In this paper, we introduce a new communication paradigm for SoCs, namely stochastic communication. The newly proposed scheme not only separates communication from computation, but also provides the required built-in fault-tolerance to DSM failures, is scalable and cheap to implement. For a generic tile-based architecture, we show how a ubiquitous multimedia application (an MP3 encoder) can be implemented using stochastic communication in an efficient and robust manner. More precisely, up to 70% data upsets, 80% packet drops because of buffer overflow, and severe levels of synchronization failures can be tolerated while maintaining a low latency.
Keywords: buffer overflow; CMOS technology; CMOS technology scaling; Costs; data upsets; Design automation; Digital audio players; Fault tolerance; Fault tolerant systems; generic tile-based architecture; integrated circuit design; integrated circuit interconnections; interconnect correctness requirements; Logic Design; logic simulation; MP3 encoder; Multiprocessor interconnection networks; on-chip fault-tolerance; on-chip stochastic communication; packet drops; Pervasive computing; Robustness; SoC design; SoC verification; Stochastic processes; Synchronisation; synchronization failures; system latency; system-level fault-tolerance; system-on-chip; systems-on-chip; video coding

Parsing and Tagging of Bilingual Dictionaries - Ma,Huanfeng; Karagol-Ayan,Burcu; David Doermann; Oard, Douglas; Wang,Jianqiang (TALTraitement Automatique Des Langues, 2003)
Bilingual dictionaries hold great potential as a source of lexical resources for training and testing automated systems for optical character recognition, machine translation, and cross-language information retrieval. In this paper, we describe a system for extracting term lexicons from printed bilingual dictionaries. Our work was divided into three phases - dictionary segmentation, entry tagging, and generation. In segmentation, pages are divided into logical entries based on structural features learned from selected examples. The extracted entries are associated with functional labels and passed to a tagging module which associates linguistic labels with each word or phrase in the entry. The output of the system is a structure that represents the entries from the dictionary. We have used this approach to parse a variety of dictionaries with both Latin and non-Latin alphabets, and demonstrate the results of term lexicon generation for retrieval from a collection of French news stories using English queries.

Pathogenic Potential of Environmental Vibrio Cholerae Strains Carrying Genetic Variants of the Toxin-Coregulated Pilus Pathogenicity Island - Faruque,Shah M.; Kamruzzaman,M.; Meraj,Ismail M.; Chowdhury,Nityananda; Nair,G. Balakrish; Sack,R. Bradley; Rita R Colwell; Sack,David A. (Infection and ImmunityInfect. Immun., 2003)
The major virulence factors of toxigenic Vibrio cholerae are cholera toxin (CT), which is encoded by a lysogenic bacteriophage (CTXΦ), and toxin-coregulated pilus (TCP), an essential colonization factor which is also the receptor for CTXΦ. The genes for the biosynthesis of TCP are part of a larger genetic element known as the TCP pathogenicity island. To assess their pathogenic potential, we analyzed environmental strains of V. cholerae carrying genetic variants of the TCP pathogenicity island for colonization of infant mice, susceptibility to CTXΦ, and diarrheagenicity in adult rabbits. Analysis of 14 environmental strains, including 3 strains carrying a new allele of the tcpA gene, 9 strains carrying a new allele of the toxT gene, and 2 strains carrying conventional tcpA and toxT genes, showed that all strains colonized infant mice with various efficiencies in competition with a control El Tor biotype strain of V. cholerae O1. Five of the 14 strains were susceptible to CTXΦ, and these transductants produced CT and caused diarrhea in adult rabbits. These results suggested that the new alleles of the tcpA and toxT genes found in environmental strains of V. cholerae encode biologically active gene products. Detection of functional homologs of the TCP island genes in environmental strains may have implications for understanding the origin and evolution of virulence genes of V. cholerae.

The people in digital libraries: Multifaceted approaches to assessing needs and impact - Marchionini,G.; Plaisant, Catherine; Komlodi,A. (Digital library use: Social practice in design and evaluationDigital library use: Social practice in design and evaluation, 2003)

Quantifying the causes of path inflation - Spring, Neil; Mahajan,R.; Anderson,T. (Topology, 2003)

Random doping-induced fluctuations of subthreshold characteristics in MOSFET devices - Andrei,Petru; Mayergoyz, Issak D (Solid-State Electronics, 2003)
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.
Keywords: Fluctuations; Mismatch; MOSFET; Sensitivity analysis; Statistics; Submicron devices

Rapid porting of DUSTer to Hindi - Dorr, Bonnie J; Ayan,Necip Fazil; Habash,Nizar; Madnani,Nitin; Hwa,Rebecca (ACM Transactions on Asian Language Information Processing (TALIP), 2003)
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.
Keywords: Divergences; Machine translation

Recovery of a Digital Image Collection Through the SDSC/UMD/NARA Prototype Persistent Archive - Smorul,Mike; JaJa, Joseph F.; McCall,Fritz; Brown,Susan Fitch; Moore,Reagan; Marciano,Richard; Chen,Sheau-Yen; Lopez,Rick; Chadduck,Robert (Instititue for Advanced Computer Studies, Univ of Maryland, College Park, 2003)
The San Diego Supercomputer Center (SDSC), the University of Maryland, and theNational Archives and Records Administration (NARA) are collaborating on building a pilot persistent archive using and extending data grid and digital library technologies. The current prototype consists of node servers at SDSC, University of Maryland, and NARA, connected through the Storage Request Broker (SRB) data grid middleware, and currently holds several terabytes of NARA selected collections. In particular, a historically important image collection that was on the verge of becoming inaccessible was fully restored and ingested into our pilot system. In this report, we describe the methodology behind our approach to fully restore this image collection and the process used to ingest it into the prototype persistent archive. (UMIACS-TR-2003-105)
Keywords: Technical Report

Reduction of Cholera in Bangladeshi Villages by Simple Filtration - Rita R Colwell; Huq,Anwar; M. Sirajul Islam; K. M. A. Aziz; Yunus,M.; N. Huda Khan; A. Mahmud; Sack,R. Bradley; Nair,G. B.; J. Chakraborty; Sack,David A.; E. Russek-Cohen (Proceedings of the National Academy of SciencesPNAS, 2003)
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.

Refactoring using event-based profiling - Nagarajan,A.; Memon, Atif M. (First International Workshop on REFactoring: Achievements, Challenges, Effects (REFACE), 2003)
Refactoring is a disciplined process of restructuring soft-ware code in order to improve it, e.g., to make it more reusable, reliable and maintainable. The source of infor- mation that guides the refactoring process may be the soft- ware’s user profiles. An increasingly important class of soft- ware is event-based software. Event-based software take an event as an input, change their state, and perhaps output an event. They provide new opportunities for refactoring. For example, reorganizing the objects related to an event and restructuring the event handlers based on the behavior of the software. These opportunities require that we collect user profiles at the level of events rather than the code and model the software in such a way that allows refactoring of event handlers. We present new techniques to collect event- level profiles and organize event handlers. We describe our techniques on one class of event-based software – Graphi- cal User Interfaces (GUIs). We demonstrate the practicality and usefulness of our techniques on a large software system.

Regression testing of GUIs - Memon, Atif M.; Soffa,Mary Lou (ACM SIGSOFT Software Engineering Notes, 2003)
Although graphical user interfaces (GUIs) constitute a large part of the software being developed today and are typically created using rapid prototyping, there are no effective regression testing techniques for GUIs. The needs of GUI regression testing differ from those of traditional software. When the structure of a GUI is modified, test cases from the original GUI are either reusable or unusable on the modified GUI. Since GUI test case generation is expensive, our goal is to make the unusable test cases usable. The idea of reusing these unusable (a.k.a. obsolete) test cases has not been explored before. In this paper, we show that for GUIs, the unusability of a large number of test cases is a serious problem. We present a novel GUI regression testing technique that first automatically determines the usable and unusable test cases from a test suite after a GUI modification. It then determines which of the unusable test cases can be repaired so they can execute on the modified GUI. The last step is to repair the test cases. Our technique is integrated into a GUI testing framework that, given a test case, automatically executes it on the GUI. We implemented our regression testing technique and demonstrate for two case studies that our approach is effective in that many of the test cases can be repaired, and is practical in terms of its time performance.
Keywords: call-tree; classification of events; GUI call-graph; GUI control-flow graph; GUI testing; regression testing; repairing test cases

Replicated studies: building a body of knowledge about software reading techniques - Shull, F.; Carver, J.; Travassos,G.H.; Maldonado,J.C.; Conradi,R.; Basili, Victor R. (SERIES ON SOFTWARE ENGINEERING AND KNOWLEDGE ENGINEERING, 2003)

A representation for abstract simplicial complexes: an analysis and a comparison - De Floriani, Leila; Morando,F.; Puppo,E. (Discrete Geometry for Computer Imagery, 2003)
Abstract simplicial complexes are used in many application contexts to represent multi-dimensional, possibly non-manifold and non-uniformly dimensional, geometric objects. In this paper we introduce a new general yet compact data structure for representing simplicial complexes, which is based on a decomposition approach that we have presented in our previous work [3]. We compare our data structure with the existing ones and we discuss in which respect it performs better than others.

Representation of non-manifold objects - De Floriani, Leila; Morando,Franco; Puppo,Enrico (Proceedings of the eighth ACM symposium on Solid modeling and applications, 2003)
In our previous work [2], we have shown that a non-manifold, mixed-dimensional object described by simplicial complexes can be decomposed in a unique way into regular components, all belonging to a well-understood class. Based on such decomposition, we define here a two-level topological data structure for representing non-manifold objects in any dimension: the first level represents components; while the second level represents the connectivity relation among them. The resulting data structure is compact and scalable, allowing for the efficient treatment of singularities without burdening well-behaved parts of a complex with excessive space overheads.
Keywords: Data structures; Non-manifold modeling; simplicial complexes

Safe and flexible memory management in Cyclone - Hicks, Michael W.; Morrisett,G.; Grossman,D.; Jim,T. (Technical Reports from UMIACS, 2003)
Cyclone is a type-safe programming language intended for applications requiring control over memory management. Our previous work on Cyclone included support for stack allocation, lexical region allocation, and a garbage-collected heap. We achieved safety (i.e., prevented dangling pointers) through a region-based type-and-effects system. This paper describes some new memory-management mechanisms that we have integrated into Cyclone: dynamic regions, unique pointers, and reference-counted objects. Our experience shows that these new mechanisms are well suited for the timely recovery of objects in situations where it is awkward to use lexical regions. Crucially, programmers can write reusable functions without unnecessarily restricting callers' choices among the variety of memory-management options. To achieve this goal, Cyclone employs a combination of polymorphism and scoped constructs that temporarily let us treat objects as if they were allocated in a lexical region.

A search engine for 3D models - Funkhouser,Thomas; Min,Patrick; Kazhdan,Michael; Chen,Joyce; Halderman,Alex; Dobkin,David; Jacobs, David W. (ACM Trans. Graph., 2003)
As the number of 3D models available on the Web grows, there is an increasing need for a search engine to help people find them. Unfortunately, traditional text-based search techniques are not always effective for 3D data. In this article, we investigate new shape-based search methods. The key challenges are to develop query methods simple enough for novice users and matching algorithms robust enough to work for arbitrary polygonal models. We present a Web-based search engine system that supports queries based on 3D sketches, 2D sketches, 3D models, and/or text keywords. For the shape-based queries, we have developed a new matching algorithm that uses spherical harmonics to compute discriminating similarity measures without requiring repair of model degeneracies or alignment of orientations. It provides 46 to 245% better performance than related shape-matching methods during precision--recall experiments, and it is fast enough to return query results from a repository of 20,000 models in under a second. The net result is a growing interactive index of 3D models available on the Web (i.e., a Google for 3D models).
Keywords: Search engine; shape matching; shape representation; shape retrieval

The sequence and analysis of Trypanosoma brucei chromosome II - El‐Sayed, Najib M.; Ghedin,E.; Song,J.; MacLeod,A.; Bringaud,F.; Larkin,C.; Wanless,D.; Peterson,J.; Hou,L.; Taylor,S.; others (Nucleic acids research, 2003)

Sex-lethal splicing autoregulation in vivo: interactions between SEX-LETHAL, the U1 snRNP and U2AF underlie male exon skipping - Nagengast,Alexis A.; Stitzinger,Shane M.; Tseng,Chin-Hsiu; Mount, Stephen M.; Salz,Helen K. (DevelopmentDevelopment, 2003)
Alternative splicing of the Sex-lethal pre-mRNA has long served as a model example of a regulated splicing event, yet the mechanism by which the female-specific SEX-LETHAL RNA-binding protein prevents inclusion of the translation-terminating male exon is not understood. Thus far, the only general splicing factor for which there is in vivo evidence for a regulatory role in the pathway leading to male-exon skipping is sans-fille (snf), a protein component of the spliceosomal U1 and U2 snRNPs. Its role, however, has remained enigmatic because of questions about whether SNF acts as part of an intact snRNP or a free protein. We provide evidence that SEX-LETHAL interacts with SANS-FILLE in the context of the U1 snRNP, through the characterization of a point mutation that interferes with both assembly into the U1 snRNP and complex formation with SEX-LETHAL. Moreover, we find that SEX-LETHAL associates with other integral U1 snRNP components, and we provide genetic evidence to support the biological relevance of these physical interactions. Similar genetic and biochemical approaches also link SEX-LETHAL with the heterodimeric splicing factor, U2AF. These studies point specifically to a mechanism by which SEX-LETHAL represses splicing by interacting with these key splicing factors at both ends of the regulated male exon. Moreover, because U2AF and the U1 snRNP are only associated transiently with the pre-mRNA during the course of spliceosome assembly, our studies are difficult to reconcile with the current model that proposes that the SEX-LETHAL blocks splicing at the second catalytic step, and instead argue that the SEX-LETHAL protein acts after splice site recognition, but before catalysis begins.
Keywords: Drosophila; SNF; Splicing regulation; SXL; U1 snRNP; U2AF

SHOP2: An HTN planning system - Nau, Dana S.; Au,T. C; Ilghami,O.; Kuter,U.; Murdock,J. W.; Wu,D.; Yaman,F. (J. Artif. Intell. Res. (JAIR), 2003)
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.

Space-Efficient and Fast Algorithms for Multidimensional Dominance Reporting and Range Counting - Shi,Qingmin; JaJa, Joseph F.; Mortensen,Christian (Instititue for Advanced Computer Studies, Univ of Maryland, College Park, 2003)
We present linear-space sublogarithmic algorithms for handling the {\emthree-dimensional dominance reporting problem} and the {\em two-dimensional range counting problem}. Under the RAM model as described in~[M.~L. Fredman and D.~E. Willard. ``Surpassing the information theoretic bound with fusion trees'', {\em Journal of Computer and System Sciences}, 47:424--436, 1993], our algorithms achieve $O(\log n/\log\log n+f)$ query time for 3-D dominance reporting, where $f$ is the number of points reported, and $O(\log n/\log\log n)$ query time for 2-D range counting case. We extend these results to any constant dimension $d$ achieving $O(n(\log n/\log\log n)^{d-3})$-space and $O((\log n/\log\log )^{d-2}+f)$-query time for the reporting case and $O(n(\log n/\log\log n)^{d-2})$-space and $O((\log n/\log\log n)^{d-1})$ query time for the counting case. (UMIACS-TR-2003-101)
Keywords: Technical Report

Special section on perceptual organization in computer vision - Jacobs, David W.; Lindenbaum,M.; August,J.; Zucker,SW; Ben-Shahar,O.; Zucker,SW; Tuytelaars,T.; Turina,A.; Van Gool,L.; Mahamud,S. (IEEE Computer Society, 2003)

Starting an intergenerational technology design team: a case study - Knudtzon,Kendra; Druin, Allison; Kaplan,Nancy; Summers,Kathryn; Chisik,Yoram; Kulkarni,Rahul; Moulthrop,Stuart; Weeks,Holly; Bederson, Benjamin B. (Proceedings of the 2003 conference on Interaction design and children, 2003)
This paper presents a case study of the first three months of a new intergenerational design team with children ages 10--13. It discusses the research and design methods used for working with children of this age group, the challenges and opportunities of starting a new team, and the lessons learned.
Keywords: children; cooperative inquiry; design methods; educational applications; intergenerational design teams; participatory design

Supporting statistical electronic table usage by citizens - Hert,Carol A.; Liddy,Elizabeth D.; Shneiderman, Ben; Marchionini,Gary (Commun. ACM, 2003)
Over 70 agencies at the federal level are charged with collecting data and producing and disseminating statistics. These statistics are used to inform government policy, shape health care initiatives, provide information on the state of the economy, and others. They also have significant impact on the lives of citizens who use the statistics, for example, to determine job opportunities, changes in social security benefits, and quality of life in particular areas. Our digital government project developed several specific technologies to support the location, manipulation, and understanding of a quintessential format for statistical information---the table.

Tagging and Parsing of Bilingual Dictionary - Ma,Huanfeng; Karagol-Ayan,Burcu; David Doermann; Oard, Douglas; Wang,Jianqiang (University of Maryland, College Park, 2003)
Bilingual dictionaries hold great potential as a source of lexical resources for training and testing automated systems for optical character recognition, machine translation, and cross-language information retrieval. In this paper, we describe a system for extracting term lexicons from printed bilingual dictionaries. Our work was divided into three phases - dictionary segmentation, entry tagging, and generation. In segmentation, pages are divided into logical entries based on structural features learned from selected examples. The extracted entries are associated with functional labels and passed to a tagging module which associates linguistic labels with each word or phrase in the entry. The output of the system is a structure that represents the entries from the dictionary. We have used this approach to parse a variety of dictionaries with both Latin and non-Latin alphabets, and demonstrate the results of term lexicon generation for retrieval from a collection of French news stories using English queries.

Technology probes: inspiring design for and with families - Hutchinson,Hilary; Mackay,Wendy; Westerlund,Bo; Bederson, Benjamin B.; Druin, Allison; Plaisant, Catherine; Beaudouin-Lafon,Michel; Conversy,Stéphane; Evans,Helen; Hansen,Heiko; Roussel,Nicolas; Eiderbäck,Björn (Proceedings of the SIGCHI conference on Human factors in computing systems, 2003)
We describe a new method for use in the process of co-designing technologies with users called technology probes. Technology probes are simple, flexible, adaptable technologies with three interdisciplinary goals: the social science goal of understanding the needs and desires of users in a real-world setting, the engineering goal of field-testing the technology, and the design goal of inspiring users and researchers to think about new technologies. We present the results of designing and deploying two technology probes, the messageProbe and the videoProbe, with diverse families in France, Sweden, and the U.S. We conclude with our plans for creating new technologies for and with families based on our experiences.
Keywords: computer mediated communication; ethnography; Home; participatory design and cooperative design

TelegraphCQ: An architectural status report - Krishnamurthy, S.; Chandrasekaran,S.; Cooper,O.; Deshpande, Amol; Franklin,M.J.; Hellerstein,J. M; Hong,W.; Madden,S.; Reiss,F.; Shah,M. A (IEEE Data Engineering Bulletin, 2003)

TelegraphCQ: continuous dataflow processing - Chandrasekaran,Sirish; Cooper,Owen; Deshpande, Amol; Franklin,Michael J.; Hellerstein,Joseph M.; Wei Hong; Krishnamurthy,Sailesh; Madden,Samuel R.; Reiss,Fred; Shah,Mehul A. (Proceedings of the 2003 ACM SIGMOD international conference on Management of data, 2003)

Topological analysis and characterization of discrete scalar fields - Danovaro,E.; De Floriani, Leila; Mesmoudi,M. (Geometry, Morphology, and Computational Imaging, 2003)
In this paper, we address the problem of analyzing the topology of discrete scalar fields defined on triangulated domains. To this aim, we introduce the notions of discrete gradient vector field and of Smalelike decomposition for the domain of a d-dimensional scalar field. We use such notions to extract the most relevant features representing the topology of the field. We describe a decomposition algorithm, which is independent of the dimension of the scalar field, and, based on it, methods for extracting the critical net of a scalar field. A complete classification of the critical points of a 2-dimensional field that corresponds to a piecewise differentiable field is also presented.

Toward a statistical knowledge network - Marchionini,Gary; Haas,Stephanie; Plaisant, Catherine; Shneiderman, Ben; Hert,Carol (Proceedings of the 2003 annual national conference on Digital government research, 2003)
This paper describes an architecture for a statistical knowledge network that depends on user interfaces as the glue among the components. These interfaces aim to serve non-expert users with diverse needs and statistical and computing experiences. Such interfaces are crucially dependent on different indexing schemes and good metadata.

Towards On-chip Fault-tolerant Communication - Tudor Dumitras; Kerner, Sam; M\uarculescu, Radu (ASP-DAC '03 Proceedings of the 2003 Asia and South Pacific Design Automation Conference, 2003)
As CMOS technology scales down into the deep-submicron (DSM) domain, devices and interconnects are subject to new types of malfunctions and failures that are harder to predict and avoid with the current system-on-chip (SoC) design methodologies. Relaxing the requirement of 100% correctness in operation drastically reduces the costs of design but, at the same time, requires SoCs be designed with some degree of system-level fault-tolerance. In this paper, we introduce a high-level model of DSM failure patterns and propose a new communication paradigm for SoCs, namely stochastic communication. Specifically, for a generic tile-based architecture, we propose a randomized algorithm which not only separates computation from communication, but also provides the required fault-tolerance to on-chip failures. This new technique is easy and cheap to implement in SoCs that integrate a large number of communicating IP cores.

Use of the SAND spatial browser for digital government applications - Samet, Hanan; Alborzi,Houman; Brabec,František; Esperança,Claudio; Hjaltason,Gísli R.; Morgan,Frank; Tanin,Egemen (Commun. ACM, 2003)
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.
Keywords: GIS

User interface evaluation and empirically-based evolution of a prototype experience management tool - Seaman,C.B; Mendonca,M.G.; Basili, Victor R.; Kim,Y. M (Software Engineering, IEEE Transactions on, 2003)
Experience management refers to the capture, structuring, analysis, synthesis, and reuse of an organization's experience in the form of documents, plans, templates, processes, data, etc. The problem of managing experience effectively is not unique to software development, but the field of software engineering has had a high-level approach to this problem for some time. The Experience Factory is an organizational infrastructure whose goal is to produce, store, and reuse experiences gained in a software development organization. This paper describes The Q-Labs Experience Management System (Q-Labs EMS), which is based on the Experience Factory concept and was developed for use in a multinational software engineering consultancy. A critical aspect of the Q-Labs EMS project is its emphasis on empirical evaluation as a major driver of its development and evolution. The initial prototype requirements were grounded in the organizational needs and vision of Q-Labs, as were the goals and evaluation criteria later used to evaluate the prototype. However, the Q-Labs EMS architecture, data model, and user interface were designed to evolve, based on evolving user needs. This paper describes this approach, including the evaluation that was conducted of the initial prototype and its implications for the further development of systems to support software experience management.
Keywords: data; development; empirical; EMS; engineering; evaluation; experience; experience; Factory; interface; interfaces; knowledge; management; management; model; models; organization; performance; prototype; Q-Labs; re-engineering; reusability; reuse; software; system; systems; tool; user

User-level internet path diagnosis - Mahajan,R.; Spring, Neil; Wetherall,D.; Anderson,T. (ACM SIGOPS Operating Systems Review, 2003)

Using computer vision to generate customized spatial audio - Mohan,A.; Duraiswami, Ramani; Zotkin,Dmitry N; DeMenthon,D.; Davis, Larry S. (Multimedia and Expo, IEEE International Conference on, 2003)
Creating high quality virtual spatial audio over headphones requires real-time head tracking, personalized head-related transfer functions (HRTFs) and customized room response models. While there are expensive solutions to address these issues based on costly head trackers, measured personalized HRTFs and room responses, these are not suitable for widespread or easy deployment and use. We report on the development of a system that uses computer vision to produce customizable models for both the HRTF and the room response, and to achieve head-tracking. The system uses relatively inexpensive cameras and widely available personal computers. Computer-vision based anthropometric measurements of the head, torso, and the external ears are used for HRTF customization. For low-frequency HRTF customization we employ a simple head-and-torso model developed recently [V. R. Algazi et al., 2002]. For high frequency customization we employ measured pinna characteristics as an index into a database of HRTFs [D. N. Zotkin et al., 2002]. For head tracking we employ an online implementation of the POSIT algorithm [D. DeMenthon and L. Davis, 1995] along with active markers to compute head pose in real-time. The system provides an enhanced virtual listening experience at low cost.

Visualizing websites using a hierarchical table of contents browser: WebTOC - Plaisant, Catherine; Marchionini,G.; Komlodi,A. (The craft of information visualization: readings and reflectionsThe craft of information visualization: readings and reflections, 2003)

What test oracle should I use for effective GUI testing? - Memon, Atif M.; Banerjee,I.; Nagarajan,A. (Automated Software Engineering, 2003. Proceedings. 18th IEEE International Conference on, 2003)
Test designers widely believe that the overall effectiveness and cost of software testing depends largely on the type and number of test cases executed on the software. In this paper we show that the test oracle used during testing also contributes significantly to test effectiveness and cost. A test oracle is a mechanism that determines whether software executed correctly for a test case. We define a test oracle to contain two essential parts: oracle information that represents expected output; and an oracle procedure that compares the oracle information with the actual output. By varying the level of detail of oracle information and changing the oracle procedure, a test designer can create different types of test oracles. We design 11 types of test oracles and empirically compare them on four software systems. We seed faults in software to create 100 faulty versions, execute 600 test cases on each version, for all 11 types of oracles. In all, we report results of 660,000 test runs on software. We show (1) the time and space requirements of the oracles, (2) that faults are detected early in the testing process when using detailed oracle information and complex oracle procedures, although at a higher cost per test case, and (3) that employing expensive oracles results in detecting a large number of faults using relatively smaller number of test cases.
Keywords: empirical studies; graphical user interface; Graphical user interfaces; GUI testing; oracle information; oracle procedure; oracle space requirement; oracle time requirements; program testing; software engineering; Software testing; test cost; test effectiveness; test oracle

The World's Information in Digital Libraries - Plaisant, Catherine; Marchimini,G.; Bruns,T.; Komlodi,A.; Campbell,L.; Rose,A.; Ding,G.M.; Beale Jr,J.; Nolet,V.; Shneiderman, Ben; others (The craft of information visualization: readings and reflectionsThe craft of information visualization: readings and reflections, 2003)

1.375-Approximation Algorithm for Sorting by Reversals - Berman,Piotr; Hannenhalli, Sridhar; Karpinski,Marek (Algorithms — ESA 2002Algorithms — ESA 2002, 2002)
Analysis of genomes evolving by inversions leads to a general combinatorial problem of Sorting by Reversals , MIN-SBR, the problem of sorting a permutation by a minimum number of reversals. Following a series of preliminary results, Hannenhalli and Pevzner developed the first exact polynomial time algorithm for the problem of sorting signed permutations by reversals, and a polynomial time algorithm for a special case of unsigned permutations. The best known approximation algorithm for MIN-SBR, due to Christie, gives a performance ratio of 1.5. In this paper, by exploiting the polynomial time algorithm for sorting signed permutations and by developing a new approximation algorithm for maximum cycle decomposition of breakpoint graphs, we design a new 1.375-algorithm for the MIN-SBR problem.

AAAI 2002 Workshops - Blake,Brian; Haigh,Karen; Hexmoor,Henry; Falcone,Rino; Soh,Leen-Kiat; Baral,Chitta; McIlraith,Sheila; Gmytrasiewicz,Piotr; Parsons,Simon; Malaka,Rainer; Krueger,Antonio; Bouquet,Paolo; et al. (AI Magazine, 2002)

Adaptive Multimedia System Architecture for Improving QoS inWireless Networks - Mahajan,A.; Mundur, Padma; Joshi,A. (Advances in Multimedia Information Processing—PCM 2002, 2002)

Algorithm Engineering and Experiments: 4th International Workshop, Alenex 2002, San Francisco, Ca, Usa, January 4-5. 2002 : Revised Papers - Mount, Dave; Stein,Clifford (Springer, 2002)
This book constitutes the thoroughly refereed post-proceedings of the 4th International Workshop on Algorithm Engineering and Experiments, ALENEX 2002, held in San Francisico, CA, USA in January 2002.The 15 revised full papers presented were carefully reviewed and selected from 34 submissions. Among the topics addressed are hewistics for algorithms, combinatorial optimization, searching, graph computation, network optimization, scheduling, computational geometry, sorting, and clustering algorithms.
Keywords: Architecture / General; Artificial intelligence; Computer algorithms; Computer algorithms/ Congresses; COMPUTERS; Computers / Computer Graphics; Computers / Computer Science; Computers / Data Modeling & Design; Computers / Data Processing; Computers / General; Computers / Programming / Algorithms; Electronic books; Mathematics / Discrete Mathematics; Medical / General

Algorithmic issues in modeling motion - Agarwal,Pankaj K.; Guibas,Leonidas J.; Edelsbrunner,Herbert; Erickson,Jeff; Isard,Michael; Har-Peled,Sariel; Hershberger,John; Jensen,Christian; Kavraki,Lydia; Koehl,Patrice; Lin,Ming; Manocha,Dinesh; et al. (ACM Comput. Surv., 2002)
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.
Keywords: computational geometry; Computer vision; mobile networks; modeling; molecular biology; motion modeling; physical simulation; robotoics; spatio-temporal databases

The Analysis and Performance of Multi-Rate Service in Distributed Video-on-Demand Systems - Mundur, Padma; Simon,R.; Sood,A. (Multimedia Tools and Applications, 2002)

Analysis of approximate nearest neighbor searching with clustered point sets - Maneewongvatana,S.; Mount, Dave (Data Structures, Near Neighbor Searches, and MethodologyData Structures, Near Neighbor Searches, and Methodology, 2002)

An Augmented Visual Query Mechanism for Finding Patterns in Time Series Data - Keogh,Eamonn; Hochheiser,Harry; Shneiderman, Ben (Flexible Query Answering SystemsFlexible Query Answering Systems, 2002)
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.

Bias in visual motion processes: A theory predicting illusions - Fermüller, Cornelia; Aloimonos, J.; Malm,H. (Statistical Methods in Video Processing.(in conjunction with European Conference on Computer Vision), 2002)
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.

CaMeL: Learning method preconditions for HTN planning - Ilghami,O.; Nau, Dana S.; Munoz-Avila,H.; Aha,D. W. (2002)
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.

Characterization of Pseudoalteromonas citrea and P. nigrifaciens Isolated from Different Ecological Habitats Based on REP-PCR Genomic Fingerprints - Ivanova,Elena P.; Matte,Glavur R.; Matte,Maria H.; Coenye,Tom; Huq,Anwarul; Rita R Colwell (Systematic and Applied Microbiology, 2002)
SummaryDNA primers corresponding to conserved repetitive interspersed genomic motifs and PCR were used to show that REP, ERIC and BOX-like DNA sequences are present in marine, oxidative, Gram-negative Pseudoalteromonas strains. REP, ERIC and BOX-PCR were used for rapid molecular characterization of both the type species of the genus and environmental strains isolated from samples collected in different geographical areas. PCR-generated genomic fingerprint patterns were found to be both complex and strain specific. Analysis of the genotypic structure of phenotypically diverse P. citrea revealed a geographic clustering of Far Eastern brown-pigmented, agar-digesting strains of this species. Marine isolates of P. nigrifaciens with 67–70% DNA relatedness generated genomic patterns different from those of the type strain and formed a separate cluster. It is concluded that REP, ERIC and BOX-PCR are effective in generating strain specific patterns that can be used to elucidate geographic distribution, with these genomic patterns providing a valuable biogeographic criterion.
Keywords: biogeography; BOX-PCR; ERIC; Pseudoalteromonas; REP

Combinatorial Algorithms for Design of DNA Arrays - Hannenhalli, Sridhar; Hubbell,Earl; Lipshutz,Robert; Pevzner,Pavel (Chip TechnologyChip Technology, 2002)
Optimal design of DNA arrays requires the development of algorithms with two-fold goals: reducing the effects caused by unintended illumination ( border length minimization problem ) and reducing the complexity of masks ( mask decomposition problem ). We describe algorithms that reduce the number of rectangles in mask decomposition by 20–30% as compared to a standard array design under the assumption that the arrangement of oligonucleotides on the array is fixed. This algorithm produces provably optimal solution for all studied real instances of array design. We also address the difficult problem of finding an arrangement which minimizes the border length and come up with a new idea of threading that significantly reduces the border length as compared to standard designs.

Communication-friendly encryption of multimedia - M. Wu; Mao,Yinian (Multimedia Signal Processing, 2002 IEEE Workshop on, 2002)
This paper discusses encryption operations that selectively encrypt content-carrying segments of multimedia data stream. We propose and analyze three techniques that work in different domains, namely, a syntax-aware selective bitstream encryption tool with bit stuffing, a generalized index mapping encryption tool with controlled overhead and an intra-bitplane encryption tool compatible with fine granularity scalable coding. The designs of these proposed encryption operations take into consideration the inherent structure and syntax of multimedia sources and have improved friendliness to communications, compression and computation.
Keywords: bit; bitstream; coding; Communication; communication; compression; compression; COMPUTATION; controlled; cryptography; data; encryption; encryption; fine; friendliness; granularity; image; index; intrabitplane; MAPPING; multimedia; operation; overhead; scalable; selective; sources; stream; stuffing; syntax-aware; syntax; tool

Complete genome sequence and comparative analysis of the metabolically versatile Pseudomonas putida KT2440 - Nelson,K. E; Weinel,C.; Paulsen,IT; Dodson,RJ; Hilbert,H.; Martins dos Santos,VAP; Fouts,DE; Gill,S. R; Pop, Mihai; Holmes,M.; others (Environmental microbiology, 2002)
Pseudomonas putida is a metabolically versatile saprophytic soil bacterium that has been certified as a biosafety host for the cloning of foreign genes. The bacterium also has considerable potential for biotechnological applications. Sequence analysis of the 6.18 Mb genome of strain KT2440 reveals diverse transport and metabolic systems. Although there is a high level of genome conservation with the pathogenic Pseudomonad Pseudomonas aeruginosa (85% of the predicted coding regions are shared), key virulence factors including exotoxin A and type III secretion systems are absent. Analysis of the genome gives insight into the non-pathogenic nature of P. putida and points to potential new applications in agriculture, biocatalysis, bioremediation and bioplastic production.

On the Complexity of Plan Adaptation by Derivational Analogy in a Universal Classical Planning Framework - Au,Tsz-Chiu; Muñoz-Avila,Héctor; Nau, Dana S. (Advances in Case-Based Reasoning, 2002)
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.
Keywords: Computer science

Compression methods for triangle meshes Preliminary version - Danovaro,E.; De Floriani, Leila; Magillo,P. (Department of Computer Science and Information Science, University of Genoa, 2002)

Computational Logic: Logic Programming and Beyond, Essays in Honour of Robert A - Eiter,T.; Mascardi,V.; V.S. Subrahmanian (Kowalski, Part I, 2002)

COTS-based software development: Processes and open issues - Morisio,M; Seaman,C.B; Basili, Victor R.; Parra,A.T; Kraft,S.E; Condon,S.E (Journal of Systems and Software, 2002)
The work described in this paper is an investigation of the COTS-based software development within a particular NASA environment, with an emphasis on the processes used. Fifteen projects using a COTS-based approach were studied and their actual process was documented. This process is evaluated to identify essential differences in comparison to traditional software development. The main differences, and the activities for which projects require more guidance, are requirements definition and COTS selection, high level design, integration and testing. Starting from these empirical observations, a new process and set of guidelines for COTS-based development are developed and briefly presented.
Keywords: Commercial off-the-shelf; Component-based; COTS; empirical study; Software development process

Cyclone: A safe dialect of C - Jim,T.; Morrisett,G.; Grossman,D.; Hicks, Michael W.; Cheney,J.; Wang, Y. (USENIX Annual Technical Conference, 2002)
Cyclone is a safe dialect of C. It has been designed from the ground up to prevent the buffer overflows, format string attacks, and memory management errors that are common in C programs, while retaining C's syntax and semantics. This paper examines safety violations enabled by C's design, and shows how Cyclone avoids them, without giving up C's hallmark control over low-level details such as data representation and memory management.

Disjunctive logic programming: A survey and assessment - Minker, Jack; Seipel,D. (Computational Logic: Logic Programming and Beyond, 2002)
We describe the fields of disjunctive logic programming and disjunctive deductive databases from the time of their inception to the current time. Contributions with respect to semantics, implementations and applications are surveyed.In the last decade many semantics have been proposed out of which we highlight what we believe to be the most influential ones and compare them. Basic ideas have been borrowed from the semantics of normal logic programs such as stable model semantics and well-founded semantics, which have been generalized in various ways to obtain semantics of disjunctive logic programs. We discuss disjunctive systems such as DLV and Smodels, and related non-disjunctive systems such as XSB and DeReS, that have been implemented. We also describe applications of disjunctive logic programming: reasoning about declarative specifications, reasoning about actions, diagnosis (e.g. in medicine or biology), and in data integration that have resource predicates defined by multiple rules. We discuss the future needs to make the field practical: e.g. integrating concepts from databases (such as aggregation), optimization methods, and object orientation.

An efficient k-means clustering algorithm: analysis and implementation - Kanungo,T.; Mount, Dave; Netanyahu,N. S; Piatko,C. D; Silverman,R.; Wu,A. Y (Pattern Analysis and Machine Intelligence, IEEE Transactions on, 2002)
In k-means clustering, we are given a set of n data points in d-dimensional space Rd and an integer k and the problem is to determine a set of k points in Rd, called centers, so as to minimize the mean squared distance from each data point to its nearest center. A popular heuristic for k-means clustering is Lloyd's (1982) algorithm. We present a simple and efficient implementation of Lloyd's k-means clustering algorithm, which we call the filtering algorithm. This algorithm is easy to implement, requiring a kd-tree as the only major data structure. We establish the practical efficiency of the filtering algorithm in two ways. First, we present a data-sensitive analysis of the algorithm's running time, which shows that the algorithm runs faster as the separation between clusters increases. Second, we present a number of empirical studies both on synthetically generated data and on real data sets from applications in color quantization, data compression, and image segmentation
Keywords: algorithm; color; algorithm; image; algorithm; kd-tree; mean; analysis; filtering; clustering; clustering; compression; data; distance; covariance; Lloyd; matrices; filtering; quantization; data; segmentation; k-means; squared; structure; data-sensitive; theory; pattern

Error-Tolerant Agents - Eiter,Thomas; Mascardi,Viviana; Subrahmanian,V. (Computational Logic: Logic Programming and BeyondComputational Logic: Logic Programming and Beyond, 2002)
The use of agents in today’s Internet world is expanding rapidly. Yet, agent developers proceed largely under the optimistic assumption that agents will be error-free. Errors may arise in agents for numerous reasons — agents may share a workspace with other agents or humans and updates made by these other entities may cause an agent to face a situation that it was not explicitly programmed to deal with. Likewise, errors in coding agents may lead to inconsistent situations where it is unclear how the agent should act. In this paper, we define an agent execution model that allows agents to continue acting “reasonably” even when some errors of the above types occur. More importantly, in our framework, agents take “repair” actions automatically when confronted with such situations, but while taking such repair actions, they can often continue to engage in work and/or interactions with other agents that are unaffected by repairs.
Keywords: Computer; Science

Evidence for a Plastid Origin of Plant Ethylene Receptor Genes - Mount, Stephen M.; Chang,Caren (Plant PhysiologyPlant Physiol., 2002)

Experiences with capsule-based active networking - Hicks, Michael W.; Moore,J. T; Wetherall,D.; Nettles,S. (DARPA Active NEtworks Conference and Exposition, 2002. Proceedings, 2002)
Active networking adds programmability to the elements of the network, most aggressively by using programmable packets, or capsules. ANTS [22, 21] and PLANet [10, 8] are the most mature examples of capsule-based systems, both having been publicly available for several years. This paper presents our experience with these systems and the lessons they hold for the future of capsule-based active networking. The paper focuses on four key issues: flexibility, performance, security, and usability. We consider how ANTS and PLANet address these issues, noting that despite substantial surface differences, both systems identify similar key problems and use closely related solutions. Based on our experience with these systems we conclude that capsule-based systems can achieve useful levels of flexibility, performance, and usability. Many aspects of security can also be adequately addressed, but some important problems related to denial of service remain as open problems
Keywords: active networking; ANTS; application-specific routing; capsule architecture; capsule-based systems; computer crime; Computer network management; Computer networks; Computer science; Contracts; Electronic switching systems; INFORMATION SCIENCE; Internet; internetworking; network management; PLANet; Planets; programmability; programmable packets; Programming; Security; Standards development; telecommunication network routing; usability

Extraction of Critical Nets Based on a Discrete Gradient Vector Field - De Floriani, Leila; Mesmoudi,M. M.; Danovaro,E. (Proceedings of Eurographics, 2002)
In this paper we address the problem of representing the topology of discrete scalar fieldsdefined on triangulated domains in two and three dimensions. To this aim, we use the notion of discrete gradient vector field that we have introduced in [3] to classify critical points and extract a critical net representing the main features of a scalar field defined on a two-dimensional domain. The nature of the critical points provided by the discrete gradient vector field is quite different from those obtained in the differentiable case. Thus, we show that our critical net generalizes classical critical nets corresponding to (the classical differentiable) Morse functions.

An extraction-based verification methodology for MEMS - Baidya,B.; Gupta,S.K.; Mukherjee,T. (Microelectromechanical Systems, Journal of, 2002)
Micromachining techniques are being increasingly used to develop miniaturized sensor and actuator systems. These system designs tend to be captured as layout, requiring extraction of the equivalent microelectromechanical circuit as a necessary step for design verification. This paper presents an extraction methodology to (re-)construct a circuit schematic representation from the layout, enabling the designer to use microelectromechanical circuit simulators to verify the functional behavior of the layout. This methodology uses a canonical representation of the given layout on which feature-based and graph-based recognition algorithms are applied to generate the equivalent extracted schematic. Extraction can be performed to either the atomic level or the functional level representation of the reconstructed circuit. The choice of level in hierarchy is governed by the trade off between simulation time and simulation accuracy of the extracted circuit. The combination of the MEMS layout extraction and lumped-parameter circuit simulation provides MEMS designers with VLSI-like tools enabling faster design cycles, and improved design productivity
Keywords: atomic level; canonical representation; circuit schematic representation; circuit simulation; design cycles; design productivity; design verification; digital simulation; equivalent circuits; equivalent microelectromechanical circuit; extraction-based verification methodology; feature-based recognition algorithms; functional behavior; functional level; graph-based recognition algorithms; layout extraction; lumped parameter networks; lumped-parameter circuit simulation; MEMS; microelectromechanical circuit simulators; micromachining techniques; micromechanical devices; simulation accuracy; simulation time

Getting real about speech: overdue or overhyped? - James,Frankie; Lai,Jennifer; Suhm,Bernhard; Balentine,Bruce; Makhoul,John; Nass,Clifford; Shneiderman, Ben (CHI '02 extended abstracts on Human factors in computing systems, 2002)
Speech has recently made headway towards becoming a more mainstream interface modality. For example, there is an increasing number of call center applications, especially in the airline and banking industries. However, speech still has many properties that cause its use to be problematic, such as its inappropriateness in both very quiet and very noisy environments, and the tendency of speech to increase cognitive load. Concerns about such problems are valid; however, they do not explain why the use of speech is so controversial in the HCI community. This panel would like to address the issues underlying the controversy around speech, by discussing the current state of the art, the reasons it is so difficult to build a good speech interface, and how HCI research can contribute to the development of speech interfaces.
Keywords: cognitive load; social responses; speech interfaces

GLEANS: A generator of logical extracts and abstracts for nice summaries - Daumé, Hal; Echihabi,A.; Marcu,D.; Munteanu,D.; Soricut,R. (Workshop on Automatic Summarization, 2002)

GUI testing: Pitfalls and process - Memon, Atif M. (IEEE Computer, 2002)

The importance of lexicalized syntax models for natural language generation tasks - Daumé, Hal; Knight,K.; Langkilde-Geary,I.; Marcu,D.; Yamada,K. (Proc. of INLG, 2002)

Inferring link weights using end-to-end measurements - Mahajan,Ratul; Spring, Neil; Wetherall,David; Anderson,Tom (Proceedings of the 2nd ACM SIGCOMM Workshop on Internet measurment, 2002)
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.

Lessons learned from 25 years of process improvement: the rise and fall of the NASA software engineering laboratory - Basili, Victor R.; McGarry,Frank E.; Pajerski,Rose; Zelkowitz, Marvin V (Proceedings of the 24th International Conference on Software Engineering, 2002)
For 25 years the NASA/GSFC Software Engineering Laboratory (SEL) has been a major resource in software process improvement activities. But due to a changing climate at NASA, agency reorganization, and budget cuts, the SEL has lost much of its impact. In this paper we describe the history of the SEL and give some lessons learned on what we did right, what we did wrong, and what others can learn from our experiences. We briefly describe the research that was conducted by the SEL, describe how we evolved our understanding of software process improvement, and provide a set of lessons learned and hypotheses that should enable future groups to learn from and improve on our quarter century of experiences.

Lexicon Acquisition from Bilingual Dictionaries - David Doermann; Ma,H.; Karagol-Ayan,B.; Oard, Douglas (SPIEPhotonic West Electronic Imaging Conference, 2002)

A local search approximation algorithm for k-means clustering - Kanungo,Tapas; Mount, Dave; Netanyahu,Nathan S.; Piatko,Christine D.; Silverman,Ruth; Wu,Angela Y. (Proceedings of the eighteenth annual symposium on Computational geometry, 2002)
In k-means clustering we are given a set of n data points in d-dimensional space Rd and an integer k, and the problem is to determine a set of k points in ÓC;d, called centers, to minimize the mean squared distance from each data point to its nearest center. No exact polynomial-time algorithms are known for this problem. Although asymptotically efficient approximation algorithms exist, these algorithms are not practical due to the extremely high constant factors involved. There are many heuristics that are used in practice, but we know of no bounds on their performance.We consider the question of whether there exists a simple and practical approximation algorithm for k-means clustering. We present a local improvement heuristic based on swapping centers in and out. We prove that this yields a (9+&egr;)-approximation algorithm. We show that the approximation factor is almost tight, by giving an example for which the algorithm achieves an approximation factor of (9-&egr;). To establish the practical value of the heuristic, we present an empirical study that shows that, when combined with Lloyd's algorithm, this heuristic performs quite well in practice.
Keywords: Approximation algorithms; clustering; computational geometry; k-means; local search

Locating and accessing data repositories with WebSemantics - Mihaila,G. A; Raschid, Louiqa; Tomasic,A. (The VLDB journal, 2002)

A logic-based approach to data integration - Grant,John; Minker, Jack (Theory Pract. Log. Program., 2002)
An important aspect of data integration involves answering queries using various resources rather than by accessing database relations. The process of transforming a query from the database relations to the resources is often referred to as query folding or answering queries using views, where the views are the resources. We present a uniform approach that includes as special cases much of the previous work on this subject. Our approach is logic-based using resolution. We deal with integrity constraints, negation, and recursion also within this framework.
Keywords: Clark completion; Data integration; materialized views; query folding; resolution method; stratified databases

Measuring ISP topologies with Rocketfuel - Spring, Neil; Mahajan,R.; Wetherall,D. (ACM SIGCOMM Computer Communication Review, 2002)

Methods and apparatus for multi-layer data hiding - Yu,Hong Heather; M. Wu; Li,Xin; Gelman,Alexander D. (2002)
A data hiding system and method for providing a method of embedding multiple layers of hidden data into multimedia data. First, a media unit of the multimedia data is evaluated to determine an appropriate embedding procedure. Next during a first embedding pass, a ruling layer of primary hidden data is embedded into the media unit. In another embedding pass, a governing layer of secondary hidden data is embedded on top of the ruling layer. The secondary hidden data provides control information for controlling the primary hidden data and the host data. Control information such as error correction data, synchronization data, decoding data, and authentication data is embedded in the governing layer. Embedding schemes such as base domain and spectrum domain embedding are employed.

Multiresolution mesh representation: Models and data structures - De Floriani, Leila; Magillo,P. (Tutorials on Multiresolution in Geometric Modelling, 2002)
Multiresolution meshes are a common basis for building representationsof a geometric shape at different levels of detail. The use of the term multiresolu- tion depends on the remark that the accuracy (or, level of detail) of a mesh in approximating a shape is related to the mesh resolution, i.e., to the density (size and number) of its cells. A multiresolution mesh provides several alternative mesh- based approximations of a spatial object (e.g., a surface describing the boundary of a solid object, or the graph of a scalar field). A multiresolution mesh is a collection of mesh fragments, describing usually small portions of a spatial object with different accuracies, plus suitable relations that allow selecting a subset of fragments (according to user-defined accuracy crite- ria), and combining them into a mesh covering the whole object, or an object part. Existing multiresolution models differ in the type of mesh fragments they consider and in the way they define relations among such fragments. In this chapter, we introduce a framework for multiresolution meshes in order to analyze and compare existing models proposed in the literature on a common basis. We have identified two sets of basic queries on a multiresolution meshes, that we call selective refinement and spatial selection. We describe two approaches for answering such queries, and discuss the primitives involved in them, which must be efficiently supported by any data structure implementing a multiresolution mesh. We then describe and analyze data structures proposed in the literature for encoding multiresolution meshes.

A new, expressed multigene family containing a hot spot for insertion of retroelements is associated with polymorphic subtelomeric regions of Trypanosoma brucei - Bringaud,F.; Biteau,N.; Melville,S. E.; Hez,S.; El‐Sayed, Najib M.; Leech,V.; Berriman,M.; Hall,N.; Donelson,J. E; Baltz,T. (Eukaryotic cell, 2002)

A noisy-channel model for document compression - Daumé, Hal; Marcu,Daniel (Proceedings of the 40th Annual Meeting on Association for Computational Linguistics, 2002)
We present a document compression system that uses a hierarchical noisy-channel model of text production. Our compression system first automatically derives the syntactic structure of each sentence and the overall discourse structure of the text given as input. The system then uses a statistical hierarchical model of text production in order to drop non-important syntactic and discourse constituents so as to generate coherent, grammatical document compressions of arbitrary length. The system outperforms both a baseline and a sentence-based compression system that operates by simplifying sequentially all sentences in a text. Our results support the claim that discourse knowledge plays an important role in document summarization.

Non-manifold decomposition in arbitrary dimensions - De Floriani, Leila; Mesmoudi,M.; Morando,F.; Puppo,E. (Discrete Geometry for Computer Imagery, 2002)
In this paper we consider the problem of decomposing a nonmanifold n-dimensional object described by an abstract simplicial complex into an assembly of ‘more-regular’ components. Manifolds, which would be natural candidates for components, cannot be used to this aim in high dimensions because they are not decidable sets. Therefore, we define d-quasi-manifolds, a decidable superset of the class of combinatorial d-manifolds that coincides with d-manifolds in dimension less or equal than two. We first introduce the notion of d-quasi-manifold complexes, then we sketch an algorithm to decompose an arbitrary complex into an assembly of quasi-manifold components abutting at non-manifold joints. This result provides a rigorous starting point for our future work, which includes designing efficient data structures for non-manifold modeling, as well as defining a notion of measure of shape complexity of such models.

Omnibase: Uniform access to heterogeneous data for question answering - Katz,B.; Felshin,S.; Yuret,D.; Ibrahim,A.; Jimmy Lin; Marton,G.; Jerome McFarland,A.; Temelkuran,B. (Natural Language Processing and Information Systems, 2002)
Although the World Wide Web contains a tremendous amount of information, the lack of uniform structure makes finding the right knowledge difficult. A solution is to turn the Web into a “virtual database” and to access it through natural language.We built Omnibase, a system that integrates heterogeneous data sources using an object- property-value model. With the help of Omnibase, our Start natural language system can now access numerous heterogeneous data sources on the Web in a uniform manner, and answers millions of user questions with high precision.

An operational process for goal-driven definition of measures - Briand,L.C.; Morasca,S.; Basili, Victor R. (Software Engineering, IEEE Transactions on, 2002)
We propose an approach (GOM/MEDEA) for defining measures of product attributes in software engineering. The approach is driven by the experimental goals of measurement, expressed via the GQM paradigm, and a set of empirical hypotheses. To make the empirical hypotheses quantitatively verifiable, GQM/MEDEA supports the definition of theoretically valid measures for the attributes of interest based on their expected mathematical properties. The empirical hypotheses are subject to experimental verification. This approach integrates several research contributions from the literature into a consistent, practical, and rigorous approach.
Keywords: attributes; definition; development; empirical; engineering; expected; experimental; goal-driven; GQM; GQM/MEDEA; hypotheses; management; mathematical; measure; measurement; metrics; operational; paradigm; process; Product; properties; quality; software; verification

Optimal edge-based shape detection - Moon, H.; Chellapa, Rama; Rosenfeld, A. (Image Processing, IEEE Transactions on, 2002)
We propose an approach to accurately detecting two-dimensional (2-D) shapes. The cross section of the shape boundary is modeled as a step function. We first derive a one-dimensional (1-D) optimal step edge operator, which minimizes both the noise power and the mean squared error between the input and the filter output. This operator is found to be the derivative of the double exponential (DODE) function, originally derived by Ben-Arie and Rao (1994). We define an operator for shape detection by extending the DODE filter along the shape's boundary contour. The responses are accumulated at the centroid of the operator to estimate the likelihood of the presence of the given shape. This method of detecting a shape is in fact a natural extension of the task of edge detection at the pixel level to the problem of global contour detection. This simple filtering scheme also provides a tool for a systematic analysis of edge-based shape detection. We investigate how the error is propagated by the shape geometry. We have found that, under general assumptions, the operator is locally linear at the peak of the response. We compute the expected shape of the response and derive some of its statistical properties. This enables us to predict both its localization and detection performance and adjust its parameters according to imaging conditions and given performance specifications. Applications to the problem of vehicle detection in aerial images, human facial feature detection, and contour tracking in video are presented.
Keywords: 1D; 2D; aerial; analysis; boundary; conditions; contour; cross; detection; DODE; double; edge; edge-based; error; error; exponential; extraction; facial; feature; filter; filter; Filtering; function; geometry; global; human; images; imaging; localization; mean; methods; NOISE; operator; optimal; optimisation; output; performance; pixel; power; propagation; properties; section; SHAPE; square; squared; statistical; step; theory; tracking; two-dimensional; vehicle; video

Page classification through logical labelling - Liang,Jian; David Doermann; Ma,M.; Guo,J. K (Pattern Recognition, 2002. Proceedings. 16th International Conference on, 2002)
We propose an integrated approach to page classification and logical labelling. Layout is represented by a fully connected attributed relational graph that is matched to the graph of an unknown document, achieving classification and labelling simultaneously. By incorporating global constraints in an integrated fashion, ambiguity at the zone level can be reduced, providing robustness to noise and variation. Models are automatically trained from sample documents. Experimental results show promise for the classification and labelling of technical article title pages, and supports the idea of a hierarchical model base.
Keywords: article; attributed; base; character; classification; constraints; document; document; experimental; global; graph; graph; hierarchical; image; images; labelling; logical; model; noise; OCR; optical; page; pages; processing; recognition; relational; results; technical; theory; title; unknown

Partitioning planar graphs with costs and weights - Mount, Dave; Stein,C. (4th International Workshop on Algorithm Engineering and Experiments, 2002)
A graph separator is a set of vertices or edges whose removal divides an input graph into components of bounded size. This paper describes new algorithms for computing separators in planar graphs as well as techniques that can be used to speed up their implementation and improve the partition quality. In particular, we consider planar graphs with costs and weights on the vertices, where weights are used to estimate the sizes of the components and costs are used to estimate the size of the separator. We show that one can find a small separator that divides the graph into components of bounded size. We describe implementations of the partitioning algorithms and discuss results of our experiments.

PASSAT: A user-centric planning framework - Myers,K.L.; Tyson,W.M.; Wolverton,M.J.; Jarvis,P.A.; Lee,T.J.; desJardins, Marie (Proceedings of the 3rd International NASA Workshop on Planning and Scheduling for Space, 2002)
We describe a plan-authoring system called PASSAT (Plan-Authoring System based on Sketches, Advice, and Templates) that combines interactive tools for constructing plans with a suite of automated and mixed-initiative capabilities designed to complement human planning skills. PASSAT is organized around a library of predefined templates that encode task networks describing standard operating procedures and previous cases. Users can select from these templates to apply during plan development, with the system providing various forms of automated assistance. A mixed-initiative plan sketch facility helps users refine outlines for plans to complete solutions, by detecting problems and proposing possible fixes. An advice capability enables user specification of high-level guidelines for plans that the system helps to enforce. Finally, PASSAT includes process facilitation mechanisms designed to help a user track and manage outstanding planning tasks and information requirements, as a means of improving the efficiency and effectiveness of the planning process. PASSAT is designed for applications for which a core of planning knowledge can be captured in predefined action models but where significant user control of the planning process is required.

Performance analysis of a simple vehicle detection algorithm - Moon, H.; Chellapa, Rama; Rosenfeld, A. (Image and Vision Computing, 2002)
We have performed an end-to-end analysis of a simple model-based vehicle detection algorithm for aerial parking lot images. We constructed a vehicle detection operator by combining four elongated edge operators designed to collect edge responses from the sides of a vehicle. We derived the detection and localization performance of this algorithm, and verified them by experiments. Performance degradation due to different camera angles and illuminations was also examined using simulated images. Another important aspect of performance characterization — whether and how much prior information about the scene improves performance — was also investigated. As a statistical diagnostic tool for the detection performance, a computational approach employing bootstrap was used.
Keywords: Aerial image; Bootstrap; empirical evaluation; Performance analysis; Vehicle detection

Performance evaluation of object detection algorithms - Mariano,V.Y.; Min,Junghye; Park,Jin-Hyeong; Kasturi,R.; Mihalcik,D.; Huiping Li; David Doermann; Drayer,T. (Pattern Recognition, 2002. Proceedings. 16th International Conference on, 2002)
The continuous development of object detection algorithms is ushering in the need for evaluation tools to quantify algorithm performance. In this paper a set of seven metrics are proposed for quantifying different aspects of a detection algorithm's performance. The strengths and weaknesses of these metrics are described. They are implemented in the Video Performance Evaluation Resource (ViPER) system and will be used to evaluate algorithms for detecting text, faces, moving people and vehicles. Results for running two previous text-detection algorithms on a common data set are presented.
Keywords: algorithms; common; data; DETECTION; detection; Evaluation; evaluation; image; object; performance; recognition; resource; set; system; text-detection; video

Perturbation technique for LLG dynamics in uniformly magnetized bodies subject to RF fields - Bertotti,G.; Mayergoyz, Issak D; Serpico,C. (Magnetics, IEEE Transactions on, 2002)
The problem of magnetization dynamics of a uniformly magnetized uniaxial particle or film, under elliptically polarized applied field, is considered. In the special case of circularly polarized applied field and particles (films) with a symmetry axis, pure time-harmonic magnetization modes exist that can be computed analytically. Deviations from these highly symmetric conditions are treated as perturbation of the symmetric case. The perturbation technique leads to the exactly solvable system of linear differential equations for the perturbations which enables one to compute higher order magnetization harmonic. The analytical solutions are obtained and then compared with numerical results.
Keywords: analytical; anisotropy; anisotropy; applied; bodies; circularly; component; constant-in-time; constant; damping; demagnetisation; demagnetizing; differential; dynamics; effective; elliptically; equation; equations; exactly; factors; field; film; films; Frequency; gyromagnetic; harmonic; higher; Landau-Lifshitz-Gilbert; large; linear; magnetic; magnetisation; magnetization; magnetization; magnetized; modes; MOTION; order; partial; particle; particles; perturbation; polarized; radio; ratio; RF; saturation; solution; solvable; system; technique; techniques; thin; time-harmonic; uniaxial; uniformly

Physical Programming: Designing Tools for Children to Create Physical Interactive - Montemayor,J.; Druin, Allison; Farber,A.; Simms,S.; Churaman,W. (Proceedings: SIGCHI, 2002)

Planning in a multi-agent environment: theory and practice - Dix,Jürgen; Muñoz-Avila,Héctor; Nau, Dana S.; Zhang,Lingling (ACM, 2002)
We give the theoretical foundations and empirical evaluation of a planning agent, shop, performing HTN planning in a multi-agent environment. shop is based on A-SHOP, an agentized version of the original SHOP HTN planning algorithm, and is integrated in the IMPACT multi-agent environment. We ran several experiments involving accessing various distributed, heterogeneous information sources, based on simplified versions of noncombatant evacuation operations, NEO's. As a result, we noticed that in such realistic settings the time spent on communication (including network time) is orders of magnitude higher than the actual inference process. This has important consequences for optimizations of such planners. Our main results are: (1) using NEO's as new, more realistic benchmarks for planners acting in an agent environment, and (2) a memoization mechanism implemented on top of shop, which improves the overall performance in a significant way.
Keywords: agent architectures; agent selection and planning; formalisms and logics

Ray interpolants for fast raytracing reflections and refractions - Atalay,F. B; Mount, Dave (Journal of WSCG (Proc. International Conf. in Central Europe on Comp. Graph., Visualization and Comp. Vision), 2002)
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.

RECOMB '02: Proceedings of the sixth annual international conference on Computational biology (ACM, 2002)
The papers in this volume were presented at the Sixth Annual International Conference on Computational Biology RECOMB 2002, held in Washington, D.C. on April 18-21, 2002. The RECOMB series was started in 1997 by Sorin Istrail, Pavel Pevzner and Michael Waterman. RECOMB '99 took place in Lyon, France, RECOMB 2000 was held in Tokyo, Japan, and RECOMB 2001 was held in Montreal, Quebec, Canada.This year's call for papers gave rise to 118 submissions, out of which the program committee selected 35 papers to be presented at the conference and included in the proceedings. Each submission was refereed by at least three members of the program committee. After the completion of the referees' reports, an extensive web-based discussion took place.RECOMB 2002 had 8 invited speakers: Ruben Abagyan (The Scripps Research Institute), Ali H. Brivanlou (Rockefeller University), Evan Eichler (Case Western Reserve University), Harold "Skip" Garner (University of Texas Southwestern Medical Center at Dallas), David Ho (Rockefeller University), Gerry Rubin (Howard Hughes Medical Institute), J. Craig Venter (Celera) and Marc Vidal (Dana-Farber Cancer Institute). The Stanislaw Ulam Memorial Lecture was given by J. Craig Venter. The Distinguished Biology Lecture was given by David Ho. The Distinguished New Technologies Lecture was given by Harold Garner.Complete final versions of many of the papers presented in the conference will appear in a special issue of the Journal of Computational Biology, which is closely affiliated with the conference.

Region-based memory management in cyclone - Grossman,Dan; Morrisett,Greg; Jim,Trevor; Hicks, Michael W.; Wang,Yanling; Cheney,James (SIGPLAN Not., 2002)
Cyclone is a type-safe programming language derived from C. The primary design goal of Cyclone is to let programmers control data representation and memory management without sacrificing type-safety. In this paper, we focus on the region-based memory management of Cyclone and its static typing discipline. The design incorporates several advancements, including support for region subtyping and a coherent integration with stack allocation and a garbage collector. To support separate compilation, Cyclone requires programmers to write some explicit region annotations, but a combination of default annotations, local type inference, and a novel treatment of region effects reduces this burden. As a result, we integrate C idioms in a region-based framework. In our experience, porting legacy C to Cyclone has required altering about 8% of the code; of the changes, only 6% (of the 8%) were region annotations.

Regular and irregular multi-resolution terrain models: a comparison - De Floriani, Leila; Magillo,Paola (Proceedings of the 10th ACM international symposium on Advances in geographic information systems, 2002)
The paper deals with the problem of modeling large-size terrain data sets. To this aim, we consider multi-resolution models based on triangle meshes. We analyze and compare two multi-resolution terrain models based on regular and irregular meshes. The two models are viewed as instances of a common multi-resolution model, that we call a multi-resolution triangle mesh. Our comparison takes into account the space requirements of the data structures implementing the two models as well their effectiveness in supporting the extraction of variable-resolution terrain representations.
Keywords: Multi-resolution; regular and irregular structures; terrain models

A Smale-like decomposition for discrete scalar fields - De Floriani, Leila; Mesmoudi,M. M.; Danovaro,E. (Pattern Recognition, 2002. Proceedings. 16th International Conference on, 2002)
In this paper we address the problem of representing the structure of the topology of a d-dimensional scalar field as a basis for constructing a multiresolution representation of the structure of such afield. To this aim, we define a discrete decomposition of a triangulated d-dimensional domain, on whose vertices the values of the field are given. We extend a Smale decomposition, defined by Thom (1949) and Smale (1960) for differentiable functions, to the discrete case, to what we call a Smale-like decomposition. We introduce the notion of discrete gradient vector field, which indicates the growth of the scalar field and matches with our decomposition. We sketch an algorithm for building a Smale-like decomposition and a graph-based representation of this decomposition. We present results for the case of two-dimensional fields.
Keywords: data; decomposition; differentiable; discrete; domain; field; fields; functions; gradient; graph-based; methods; multidimensional; multiresolution; representation; scalar; Smale-like; structure; Topology; triangulated; vector; visualisation

Space-efficient approximate Voronoi diagrams - Arya,Sunil; Malamatos,Theocharis; Mount, Dave (Proceedings of the thiry-fourth annual ACM symposium on Theory of computing, 2002)
(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.

State of the art in data representation for visualization - Chen,B.; Kaufman,A.; Mueller,K.; Varshney, Amitabh (IEEE Visualization Tutorial, 2002)

Theoretical and Empirical Aspects of a Planner in a Multi-agent Environment - Dix,Jürgen; Munoz-Avila,Hector; Nau, Dana S.; Zhang,Lingling (Logics in Artificial Intelligence, 2002)
We give the theoretical foundations and empirical evaluation of a planning agent, ashop, performing HTN planning in a multi-agent environment. ashop is based on ASHOP , an agentised version of the original SHOP HTN planning algorithm, and is integrated in the IMPACT multi-agent environment. We ran several experiments involving accessing various distributed, heterogeneous information sources, based on simplified versions of noncombatant evacuation operations, NEO’s. As a result, we noticed that in such realistic settings the time spent on communication (including network time) is orders of magnitude higher than the actual inference process. This has important consequences for optimisations of such planners. Our main results are: (1) using NEO’s as new, more realistic benchmarks for planners acting in an agent environment, and (2) a memoization mechanism implemented on top of shop, which improves the overall performance considerably.
Keywords: Computer science

Using independent auditors as intrusion detection systems - Molina,J.; Arbaugh, William A. (Information and Communications Security, 2002)

View-Based Recognition of Military Vehicles in Ladar Imagery Using CAD Model Matching - Der, S.Z.; Zheng,Q.; Redman, B.; Chellapa, Rama; Mahmoud, H. (OPTICAL ENGINEERING-NEW YORK-MARCEL DEKKER INCORPORATED-, 2002)

Virtual audio system customization using visual matching of ear parameters - Zotkin,Dmitry N; Duraiswami, Ramani; Davis, Larry S.; Mohan,A.; Raykar,V. (16th International Conference on Pattern Recognition, 2002. Proceedings, 2002)
Applications in the creation of virtual auditory spaces (VAS) and sonification require individualized head related transfer functions (HRTFs) for perceptual fidelity. HRTFs exhibit significant variation from person to person due to differences between their pinnae, and their body sizes. We propose and preliminarily implement a simple HRTF customization based on the use of a published database of HRTFs (Algazi et al., 2001) that also contains geometrical measurements of subject pinnae. We measure some of these features via simple image processing, and select the HRTF that has features most closely corresponding to the individual's features. This selection procedure is implemented along with the virtual auditory system described in (Zotkin et al., 2002), and listener tests conducted comparing the customized HRTF and a fixed HRTF. Despite the simplicity of the method, tests reveal average improvement in localization accuracy of about 25 percent, though performance improvement varies with source location and individuals.
Keywords: acoustic signal processing; Audio systems; Auditory system; Computer vision; database; Ear; ear parameter matching; geometrical measurements; Head; head related transfer functions; HRTF customization; Image databases; IMAGE PROCESSING; medical image processing; performance improvement; Position measurement; sonification; Spatial databases; System testing; Transfer functions; virtual audio system customization; virtual auditory spaces; virtual auditory system; visual matching

Virtual Telescopes in Education - Hoban,S.; desJardins, Marie; Farrell,N.; Rathod,P.; Sachs,J.; Sansare,S.; Yesha,Y.; Keating,J.; Busschots,B.; Means,J.; others (Journal of Digital Information, 2002)
Virtual Telescopes in Education is providing the services required to operate a virtual observatory comprising distributed telescopes, including an interactive, constraint-based scheduling service, data and resource archive, proposal preparation and review environment, and a VTIE Journal. A major goal of VTIE is to elicit from learners questions about the nature of celestial objects and the physical processes that give rise to the spectacular imagery that catches their imaginations. Generation of constrained science questions will assist learners in the science process. To achieve interoperability with other NSDL resources, our approach follows the Open Archives Initiative and the W3C Semantic Web activity.