Stochastic simulations with graphics hardware: Characterization of accuracy and performance - Balijepalli,A.; LeBrun,T. W.; Gupta,S.K. (Journal of Computing and Information Science in Engineering, 2010)

Technology-Mediated Social Participation: Deep Science and Extreme Technology - Shneiderman, Ben (Active Media TechnologyActive Media Technology, 2010)
The dramatic success of social media such as Facebook, Twitter, YouTube, Flickr, blogs, and traditional discussion groups empowers individuals to become active in local and global communities. With modest redesign, these technologies can be harnessed to support national priorities such as healthcare/wellness, disaster response, community safety, energy sustainability, etc. This talk describes a research agenda for these topics that develops deep science questions and extreme technology challenges.

A tree-based approach to integrated action localization, recognition and segmentation - Zhuolin Jiang; Lin,Z.; Davis, Larry S. (ECCV Workshops, 2010)
A tree-based approach to integrated action segmentation,localization and recognition is proposed. An action is represented as a sequence of joint hog-flow descriptors extracted independently from each frame. During training, a set of action prototypes is first learned based on a k-means clustering, and then a binary tree model is constructed from the set of action prototypes based on hierarchical k-means cluster- ing. Each tree node is characterized by a shape-motion descriptor and a rejection threshold, and an action segmentation mask is defined for leaf nodes (corresponding to a prototype). During testing, an action is local- ized by mapping each test frame to a nearest neighbor prototype using a fast matching method to search the learned tree, followed by global fil- tering refinement. An action is recognized by maximizing the sum of the joint probabilities of the action category and action prototype over test frames. Our approach does not explicitly rely on human tracking and background subtraction, and enables action localization and recognition in realistic and challenging conditions (such as crowded backgrounds). Experimental results show that our approach can achieve recognition rates of 100% on the CMU action dataset and 100% on the Weizmann dataset.

Understanding Interactive Legends: a Comparative Evaluation with Standard Widgets - Riche,Nathalie Henry; Lee,Bongshin; Plaisant, Catherine (Computer Graphics Forum, 2010)
Interactive information visualization systems rely on widgets to allow users to interact with the data and modify the representation. We define interactive legends as a class of controls combining the visual representation of static legends and interaction mechanisms of widgets. As interactive legends start to appear in popular websites, we categorize their designs for common data types and evaluate their effectiveness compare to standard widgets. Results suggest that 1) interactive legends can lead to faster perception of the mapping between data values and visual encodings and 2) interaction time is affected differently depending on the data type. Additionally, our study indicates superiority both in terms of perception and interaction of ordinal controls over numerical ones. Numerical techniques are mostly used in today's systems. By providing solutions to allowing users to modify ranges interactively, we believe that interactive legends make it possible to increase the use of ordinal techniques for visual exploration.
Keywords: H.5 [Information Interfaces and Presentation]: Miscellaneous—

Validating the systematic position of ıt Plationus Segers, Murugan & Dumont, 1993 (Rotifera: Brachionidae) using sequences of the large subunit of the nuclear ribosomal DNA and of cytochrome C oxidase - Reyna-Fabian,ME; Laclette,J. P; Cummings, Michael P.; García-Varela,M (Hydrobiologia, 2010)
Members of the family Brachionidae are free-living organisms that range in size from 170 to 250 microns. They comprise part of the zooplankton in freshwater and marine systems worldwide. Morphologically, members of the family are characterized by a single piece loricated body without furrows, grooves, sulci or dorsal head shields, and a malleate trophi. Differences in these structures have been traditionally used to recognize 217 species that are classified into seven genera. However, the validity of the species, Plationus patulus, P. patulus macracanthus P. polyacanthus, and P. felicitas have been confused because they were alternatively assigned in Brachionus or Platyias, when considering only morphological and ecological characters. Based on scanning electron microscope (SEM) images of the trophi, these taxa were assigned in a new genus, Plationus. In this study, we examined the systematic position of P. patulus and P. patulus macracanthus using DNA sequences of two genes: the cytochrome oxidase subunit 1 (cox1) and domains D2 and D3 of the large subunit of the nuclear ribosomal RNA (LSU). In addition, the cox1 and LSU sequences representing five genera of Brachionidae (Anuraeopsis, Brachionus, Keratella, Plationus, and Platyias) plus four species of three families from the order Ploima were used as the outgroup. The maximum likelihood (ML) analyses were conducted for each individual gene as well as for the combined (cox1 + LSU) data set. The ML tree from the combined data set yielded the family Brachionidae as a monophyletic group with weak bootstrap support (< 50%). Five main clades in this tree had high (> 85%) bootstrap support. The first clade was composed of three populations of P. patulus + P. patulus macracanthus. The second clade was composed of a single species of Platyias. The third clade was composed of six species of Brachionus. The fourth clade included a single species of the genus Anuraeopsis, and the fifth clade was composed of three species of the genus Keratella. The genetic divergence between Plationus and Platyias ranged from 18.4 to 19.2% for cox1, and from 4.5 to 4.9% for LSU, and between Brachionus and Plationus, it ranged from 16.9 to 23.1% (cox1), and from 7.3 to 9.1% (LSU). Morphological evidence, the amount of genetic divergence, the systematic position of Plationus within the family Brachionidae, and the position of Plationus as a sister group of Brachionus and Platyias support the validity of Plationus patulus and P. patulus macracanthus into the genus Plationus.
Keywords: Cox1; likelihood; LSU; maximum; Phylogeny; Plationus

Visualizing Threaded Conversation Networks: Mining Message Boards and Email Lists for Actionable Insights - Hansen,Derek; Shneiderman, Ben; Smith,Marc (Active Media TechnologyActive Media Technology, 2010)
Analyzing complex online relationships is a difficult job, but new information visualization tools are enabling a wider range of users to make actionable insights from the growing volume of online data. This paper describes the challenges and methods for conducting analyses of threaded conversations such as found in enterprise message boards, email lists, and forums. After defining threaded conversation, we characterize the types of networks that can be extracted from them. We then provide 3 mini case studies to illustrate how actionable insights for community managers can be gained by applying the network analysis metrics and visualizations available in the free, open source NodeXL tool, which is a powerful, yet easy-to-use tool embedded in Excel 2007/2010.

VizWiz: nearly real-time answers to visual questions - Bigham,Jeffrey P.; Jayant,Chandrika; Ji,Hanjie; Little,Greg; Miller,Andrew; Miller,Robert C.; Miller,Robin; Tatarowicz,Aubrey; White,Brandyn; White,Samual; Tom Yeh (Proceedings of the 23nd annual ACM symposium on User interface software and technology, 2010)
The lack of access to visual information like text labels, icons, and colors can cause frustration and decrease independence for blind people. Current access technology uses automatic approaches to address some problems in this space, but the technology is error-prone, limited in scope, and quite expensive. In this paper, we introduce VizWiz, a talking application for mobile phones that offers a new alternative to answering visual questions in nearly real-time - asking multiple people on the web. To support answering questions quickly, we introduce a general approach for intelligently recruiting human workers in advance called quikTurkit so that workers are available when new questions arrive. A field deployment with 11 blind participants illustrates that blind people can effectively use VizWiz to cheaply answer questions in their everyday lives, highlighting issues that automatic approaches will need to address to be useful. Finally, we illustrate the potential of using VizWiz as part of the participatory design of advanced tools by using it to build and evaluate VizWiz::LocateIt, an interactive mobile tool that helps blind people solve general visual search problems.
Keywords: blind users; non-visual interfaces; real-time human computation

WATTR: a method for self-powered wireless sensing of water activity in the home - Campbell,Tim; Larson,Eric; Cohn,Gabe; Jon Froehlich; Alcaide,Ramses; Patel,Shwetak N. (Proceedings of the 12th ACM international conference on Ubiquitous computing, 2010)
Keywords: power harvesting; sensing; water conservation

Web-scale computer vision using MapReduce for multimedia data mining - White,Brandyn; Tom Yeh; Jimmy Lin; Davis, Larry S. (Proceedings of the Tenth International Workshop on Multimedia Data Mining, 2010)
This work explores computer vision applications of the MapReduce framework that are relevant to the data mining community. An overview of MapReduce and common design patterns are provided for those with limited MapReduce background. We discuss both the high level theory and the low level implementation for several computer vision algorithms: classifier training, sliding windows, clustering, bag-of-features, background subtraction, and image registration. Experimental results for the k-means clustering and single Gaussian background subtraction algorithms are performed on a 410 node Hadoop cluster.
Keywords: background subtraction; bag-of-features; Cloud computing; clustering; Computer vision; image registration; MapReduce

When is it better not to look ahead? - Nau, Dana S.; Luštrek,Mitja; Parker,Austin; Bratko,Ivan; Gams,Matjaž (Artificial Intelligence, 2010)
In situations where one needs to make a sequence of decisions, it is often believed that looking ahead will help produce better decisions. However, it was shown 30 years ago that there are “pathological” situations in which looking ahead is counterproductive. Two long-standing open questions are (a) what combinations of factors have the biggest influence on whether lookahead pathology occurs, and (b) whether it occurs in real-world decision-making.This paper includes simulation results for several synthetic game-tree models, and experimental results for three well-known board games: two chess endgames, kalah (with some modifications to facilitate experimentation), and the 8-puzzle. The simulations show the interplay between lookahead pathology and several factors that affect it; and the experiments confirm the trends predicted by the simulation models. The experiments also show that lookahead pathology is more common than has been thought: all three games contain situations where it occurs.
Keywords: Game-tree search; Lookahead pathology; minimax

3D Face Recognition: Technology and Applications - Tistarelli,M.; Li, S.Z.; Chellapa, Rama; Akarun, L. (Handbook of Remote Biometrics, 2009)

Advanced Technologies for Touchless Fingerprint Recognition - Tistarelli,M.; Li, S.Z.; Chellapa, Rama (Handbook of Remote Biometrics, 2009)

Algorithms for extraction of nanowire lengths and positions from optical section microscopy image sequence - Peng,T.; Balijepalli,A.; Gupta,S.K.; LeBrun,T. W. (Journal of Computing and Information Science in Engineering, 2009)

All Bits Are Not Equal - A Study of IEEE 802.11 Communication Bit Errors - Han,Bo; Ji,Lusheng; Lee,Seungjoon; Bhattacharjee, Bobby; Miller,R.R. (INFOCOM 2009, IEEE, 2009)
In IEEE 802.11 Wireless LAN (WLAN) systems, techniques such as acknowledgement, retransmission, and transmission rate adaptation, are frame-level mechanisms designed for combating transmission errors. Recently sub-frame level mechanisms such as frame combining have been proposed by the research community. In this paper, we present results obtained from our bit error study for identifying sub-frame error patterns because we believe that identifiable bit error patterns can potentially introduce new opportunities in channel coding, network coding, forward error correction (FEC), and frame combining mechanisms. We have constructed a number of IEEE 802.11 wireless LAN testbeds and conducted extensive experiments to study the characteristics of bit errors and their location distribution. Conventional wisdom dictates that bit error probability is the result of channel condition and ought to follow corresponding distribution. However our measurement results identify three repeatable bit error patterns that are not induced by channel conditions. We have verified that such error patterns are present in WLAN transmissions in different physical environments and across different wireless LAN hardware platforms. We also discuss our current hypotheses for the reasons behind these bit error probability patterns and how identifying these patterns may help improving WLAN transmission robustness.
Keywords: 802.11; bit; coding; error; coding; forward; coding; subframe; combining; Communication; correction; frame; correction; wireless; error; errors; channel; errors; wireless; IEEE; LAN; LAN; channel; mechanisms; network; patterns; transmission; statistics; forward

Appearance Modeling Using a Geometric Transform - Li,Jian; Zhou,S. K; Chellapa, Rama (Image Processing, IEEE Transactions on, 2009)
A general transform, called the geometric transform (GeT), that models the appearance inside a closed contour is proposed. The proposed GeT is a functional of an image intensity function and a region indicator function derived from a closed contour. It can be designed to combine the shape and appearance information at different resolutions and to generate models invariant to deformation, articulation, or occlusion. By choosing appropriate functionals and region indicator functions, the GeT unifies Radon transform, trace transform, and a class of image warpings. By varying the region indicator and the types of features used for appearance modeling, five novel types of GeTs are introduced and applied to fingerprinting the appearance inside a contour. They include the GeTs based on a level set, shape matching, feature curves, and the GeT invariant to occlusion, and a multiresolution GeT (MRGeT). Applications of GeT to pedestrian identity recognition, human body part segmentation, and image synthesis are illustrated. The proposed approach produces promising results when applied to fingerprinting the appearance of a human and body parts despite the presence of nonrigid deformations and articulated motion.
Keywords: body; contour; feature; curve; fingerprinting; geometric; function; image; function; shape; geometry; image; identity; indicator; INTENSITY; matching; trace; method; pedestrian; modeling; closed; part; Radon; recognition; region; resolution; image; segmentation; segmentation; image; set; synthesis; image; transform; appearance; transform; human; transform; Radon; transforms; computational; warping; level

ARDB-Antibiotic Resistance Genes Database - Liu,B.; Pop, Mihai (Nucleic Acids Research, 2009)
The treatment of infections is increasingly compromised by the ability of bacteria to develop resistance to antibiotics through mutations or through the acquisition of resistance genes. Antibiotic resistance genes also have the potential to be used for bio-terror purposes through genetically modified organisms. In order to facilitate the identification and characterization of these genes, we have created a manually curated database—the Antibiotic Resistance Genes Database (ARDB)—unifying most of the publicly available information on antibiotic resistance. Each gene and resistance type is annotated with rich information, including resistance profile, mechanism of action, ontology, COG and CDD annotations, as well as external links to sequence and protein databases. Our database also supports sequence similarity searches and implements an initial version of a tool for characterizing common mutations that confer antibiotic resistance. The information we provide can be used as compendium of antibiotic resistance factors as well as to identify the resistance genes of newly sequenced genes, genomes, or metagenomes. Currently, ARDB contains resistance information for 13 293 genes, 377 types, 257 antibiotics, 632 genomes, 933 species and 124 genera. ARDB is available at http://ardb.cbcb.umd.edu/.

Brute force and indexed approaches to pairwise document similarity comparisons with MapReduce - Jimmy Lin (Proceedings of the 32nd international ACM SIGIR conference on Research and development in information retrieval, 2009)
This paper explores the problem of computing pairwise similarity on document collections, focusing on the application of "more like this" queries in the life sciences domain. Three MapReduce algorithms are introduced: one based on brute force, a second where the problem is treated as large-scale ad hoc retrieval, and a third based on the Cartesian product of postings lists. Each algorithm supports one or more approximations that trade effectiveness for efficiency, the characteristics of which are studied experimentally. Results show that the brute force algorithm is the most efficient of the three when exact similarity is desired. However, the other two algorithms support approximations that yield large efficiency gains without significant loss of effectiveness.
Keywords: distributed algorithms; hadoop

Call for Papers: Special Issue of the Journal of Parallel and Distributed Computing: Cloud Computing - Chockler,Gregory; Dekel,Eliezer; JaJa, Joseph F.; Jimmy Lin (J. Parallel Distrib. Comput., 2009)

Channel Access Throttling for Improving WLAN QoS - Han,Bo; Ji,Lusheng; Lee,Seungjoon; Miller,R.R.; Bhattacharjee, Bobby (Sensor, Mesh and Ad Hoc Communications and Networks, 2009. SECON '09. 6th Annual IEEE Communications Society Conference on, 2009)
The de facto QoS channel access method for the IEEE 802.11 Wireless LANs is the Enhanced Distributed Channel Access (EDCA) mechanism, which differentiates transmission treatments for data frames belonging to different traffic categories with four different levels of channel access priority. In this paper, we propose extending EDCA with Channel Access Throttling (CAT) for more flexible and efficient QoS support. By assigning different member stations different channel access parameters, CAT differentiates channel access priorities not between traffic categories but between member stations. Then by dynamically changing the channel access parameters of each member station based on a pre-computed schedule, CAT enables EDCA WLANs the benefits of scheduled access QoS. We also present evaluation results of CAT obtained from both simulations and experiments conducted using off-the-shelf WLAN hardware and open-source device driver. Our results show that CAT can proportionally partition channel capacity, significantly improve performance of multimedia applications, effectively achieve performance protection for admitted flows, and increase per cell VoIP call capacity by up to 41%.
Keywords: 802.11; access; area; call; capacity; data; capacity; quality; capacity; WLAN; categories; transmission; channel; device; distributed; driver; quality; facto; frames; de; IEEE; LAN; LAN; VoIP; local; mechanism; member; method; enhanced; multimedia; network; wireless; networks; channel; of; parameters; channel; priority; channel; QoS; QoS; channel; service; telecommunication; service; traffic; standards; telecommunication; stations; open-source; throttling; channel; traffic; wireless; treatments; wireless; wireless

Channel Access Throttling for Overlapping BSS Management - Han,Bo; Ji,Lusheng; Lee,Seungjoon; Miller,R.R.; Bhattacharjee, Bobby (Communications, 2009. ICC '09. IEEE International Conference on, 2009)
Multiple co-channel WLAN BSSes (i.e., WLAN cells) overlapping in coverage are generally considered undesirable because members of the OBSSes compete for channel access, which typically increases the contention level of wireless medium access and reduces overall system performance. In this paper, we propose to use channel access throttling (CAT) for managing Wireless LAN radio resources for overlapping BSSes (OBSSes). CAT provides an access point (AP) of each BSS with a mechanism to control channel access parameters of its member stations on the fly. By coordinating the CAT operations of the OBSS APs, we can enable privileged channel access to an individual BSS at a particular time, for example, by assigning high priority access parameters to member stations associated with the BSS. By controlling how much each BSS may be given the privileged channel access, we can also achieve a proportional partitioning of channel capacity among OBSSes. We present evaluation results obtained from both simulations and experiments using testbed built with commercial off-the-shelf (COTS) WLAN hardware and open-source device driver. Our results show that with CAT, not only can we proportionally partition channel capacity among the OBSSes, but also improve channel utilization efficiency and increase overall capacity.
Keywords: access; access; cellular; allocation; channel; BSS; capacity; computer; capacity; proportional; cell; open-source; channel; channels; co-channel; device; driver; overlapping; efficiency; high-priority; LAN; wireless; management; partition; management; wireless; medium; network; parameters; multiple; partitioning; radio; radio; channel; resources; wireless; throttling; channel; utilization; WLAN

Classic triangular mesh subdivision algorithm - Zhuolin Jiang; Li,S.F.; Jia,X.P.; Zhu,H.L. (Jisuanji Gongcheng/ Computer Engineering, 2009)
This paper makes a concise introduction to seven classic algorithms of triangular mesh subdivision, and makes a classification and comparison between them according to their continuity, own advantage and application status. In order to improve the visualization of triangular mesh subdivision, interactive display control is implemented by using MFC and OpenGL while state machine model based on functional class is used as the software operating pattern. On the basis of this, the prototype implementation of Loop algorithm is performed. The improved method of solving existing problematic issues from prototype implementation is presented.

Classification of non-manifold singularities from transformations of 2-manifolds - Leon,J.-C.; De Floriani, Leila; Hetroy,F. (Shape Modeling and Applications, 2009. SMI 2009. IEEE International Conference on, 2009)
Non-manifold models are frequently encountered in engineering simulations and design as well as in computer graphics. However, these models lack shape characterization for modelling and searching purposes. Topological properties act as a kernel for deriving key features of objects. Here we propose a classification for the non-manifold singularities of non-manifold objects through continuous shape transformations of 2-manifolds without boundary up to the creation of non-manifold singularities. As a result, the non-manifold objects thus created can be categorized and contribute to the definition of a general purpose taxonomy for non-manifold shapes.
Keywords: classification; search; Computer; graphic; continuous; graphics; pattern; model; nonmanifold; problems; topology; property; computer; SHAPE; singularity; topological; transformation; nonmanifold

Collusion-free multiparty computation in the mediated model - Alwen,J.; Katz, Jonathan; Lindell,Y.; Persiano,G.; Shelat,A.; Visconti,I. (Advances in Cryptology-CRYPTO 2009, 2009)
Collusion-free protocols prevent subliminal communication (i.e., covert channels) between parties running the protocol. In the standard communication model, if one-way functions exist, then protocols satisfying any reasonable degree of privacy cannot be collusion-free. To circumvent this impossibility, Alwen, shelat and Visconti (CRYPTO 2008) recently suggested the mediated model where all communication passes through a mediator. The goal is to design protocols where collusion-freeness is guaranteed as long as the mediator is honest, while standard security guarantees hold if the mediator is dishonest. In this model, they gave constructions of collusion-free protocols for commitments and zero-knowledge proofs in the two-party setting.We strengthen the definition of Alwen et al., and resolve the main open questions in this area by showing a collusion-free protocol (in the mediated model) for computing any multi-party functionality.

Common effect of antipsychotics on the biosynthesis and regulation of fatty acids and cholesterol supports a key role of lipid homeostasis in schizophrenia - Polymeropoulos,Mihael H.; Licamele,Louis; Volpi,Simona; Mack,Kendra; Mitkus,Shruti N.; Carstea,Eugene D.; Getoor, Lise; Thompson,Andrew; Lavedan,Christian (Schizophrenia Research, 2009)
For decades, the dopamine hypothesis has gained the most attention in an attempt to explain the origin and the symptoms of schizophrenia. While this hypothesis offers an explanation for the relationship between psychotic symptoms and dopamine kinetics, it does not provide a direct explanation of the etiology of schizophrenia which remains poorly understood. Consequently, current antipsychotics that target neurotransmitter receptors, have limited and inconsistent efficacy. To gain insights into the mechanism of action of these drugs, we studied the expression profile of 12,490 human genes in a cell line treated with 18 antipsychotics, and compared it to that of a library of 448 other compounds used in a variety of disorders. Analysis reveals a common effect of antipsychotics on the biosynthesis and regulation of fatty acids and cholesterol, which is discussed in the context of a lipid hypothesis where alterations in lipid homeostasis might underlie the pathogenesis of schizophrenia. This finding may help research aimed at the development of novel treatments for this devastating disease.
Keywords: Antipsychotic action; Gene expression; Lipid homeostasis; Pathogenesis

Comparative genomics reveals mechanism for short-term and long-term clonal transitions in pandemic Vibrio cholerae - Chun,J.; Grim,C. J.; Hasan,N. A.; Lee,J. H.; Choi,S. Y.; Haley,B. J.; Taviani,E.; Jeon,Y. S.; Kim,D.W.; Lee,J. H.; Rita R Colwell (Proceedings of the National Academy of Sciences, 2009)
Vibrio cholerae, the causative agent of cholera, is a bacterium autochthonous to the aquatic environment, and a serious public health threat. V. cholerae serogroup O1 is responsible for the previous two cholera pandemics, in which classical and El Tor biotypes were dominant in the sixth and the current seventh pandemics, respectively. Cholera researchers continually face newly emerging and reemerging pathogenic clones carrying diverse combinations of phenotypic and genotypic properties, which significantly hampered control of the disease. To elucidate evolutionary mechanisms governing genetic diversity of pandemic V. cholerae, we compared the genome sequences of 23 V. cholerae strains isolated from a variety of sources over the past 98 years. The genome-based phylogeny revealed 12 distinct V. cholerae lineages, of which one comprises both O1 classical and El Tor biotypes. All seventh pandemic clones share nearly identical gene content. Using analogy to influenza virology, we define the transition from sixth to seventh pandemic strains as a “shift” between pathogenic clones belonging to the same O1 serogroup, but from significantly different phyletic lineages. In contrast, transition among clones during the present pandemic period is characterized as a “drift” between clones, differentiated mainly by varying composition of laterally transferred genomic islands, resulting in emergence of variants, exemplified by V. cholerae O139 and V. cholerae O1 El Tor hybrid clones. Based on the comparative genomics it is concluded that V. cholerae undergoes extensive genetic recombination via lateral gene transfer, and, therefore, genome assortment, not serogroup, should be used to define pathogenic V. cholerae clones.

Component forensics - Swaminathan,A.; M. Wu; Liu,K. J.R (Signal Processing Magazine, IEEE, 2009)
Visual sensor technologies have experienced tremendous growth in recent decades, and digital devices are becoming ubiquitous. Digital images taken by various imaging devices have been used in a growing number of applications, from military and reconnaissance to medical diagnosis and consumer photography. Consequently, a series of new forensic issues arise amidst such rapid advancement and widespread adoption of imaging technologies. For example, one can readily ask what kinds of hardware and software components as well as their parameters have been employed inside these devices? Given a digital image, which imaging sensor or which brand of sensor was used to acquire the image? How was the image acquired? Was it captured using a digital camera, cell phone camera, image scanner, or was it created artificially using an imageediting software? Has the image undergone any manipulation after capture? Is it authentic, or has it been tampered in any way? Does it contain any hidden information or steganographic data? Many of these forensic questions are related to tracing the origin of the digital image to its creation process. Evidence obtained from such analysis would provide useful forensic information to law enforcement, security, and intelligence agencies. Knowledge of image acquisition techniques can also help answer further forensic questions regarding the nature of additional processing that the image might have undergone after capture.
Keywords: ACQUISITION; component; data; forensics; digital; image; of; processing; image; sensor; sensors; security; technique; visual; technology; image

Computational linguistics for metadata building (CLiMB): using text mining for the automatic identification, categorization, and disambiguation of subject terms for image metadata - Klavans,J. L; Sheffield,C.; Abels,E.; Jimmy Lin; Passonneau,R.; Sidhu,T.; Soergel,D. (Multimedia Tools and Applications, 2009)
In this paper, we present a system using computational linguistic techniques to extract metadata for image access. We discuss the implementation, functionality and evaluation of an image catalogers’ toolkit, developed in the Computational Linguistics for Metadata Building (CLiMB) research project. We have tested components of the system, including phrase finding for the art and architecture domain, functional semantic labeling using machine learning, and disambiguation of terms in domain-specific text vis a vis a rich thesaurus of subject terms, geographic and artist names. We present specific results on disambiguation techniques and on the nature of the ambiguity problem given the thesaurus, resources, and domain-specific text resource, with a comparison of domain-general resources and text. Our primary user group for evaluation has been the cataloger expert with specific expertise in the fields of painting, sculpture, and vernacular and landscape architecture.

On Computing Compression Trees for Data Collection in Sensor Networks - Li,Jian; Deshpande, Amol; Khuller, Samir (arXiv:0907.5442, 2009)
We address the problem of efficiently gathering correlated data from a wired or a wireless sensor network, with the aim of designing algorithms with provable optimality guarantees, and understanding how close we can get to the known theoretical lower bounds. Our proposed approach is based on finding an optimal or a near-optimal {\em compression tree} for a given sensor network: a compression tree is a directed tree over the sensor network nodes such that the value of a node is compressed using the value of its parent. We consider this problem under different communication models, including the {\em broadcast communication} model that enables many new opportunities for energy-efficient data collection. We draw connections between the data collection problem and a previously studied graph concept, called {\em weakly connected dominating sets}, and we use this to develop novel approximation algorithms for the problem. We present comparative results on several synthetic and real-world datasets showing that our algorithms construct near-optimal compression trees that yield a significant reduction in the data collection cost.
Keywords: Computer Science - Information Theory; Computer Science - Networking and Internet Architecture

Consensus answers for queries over probabilistic databases - Li,Jian; Deshpande, Amol (Proceedings of the twenty-eighth ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems, 2009)
We address the problem of finding a "best" deterministic query answer to a query over a probabilistic database. For this purpose, we propose the notion of a consensus world (or a consensus answer) which is a deterministic world (answer) that minimizes the expected distance to the possible worlds (answers). This problem can be seen as a generalization of the well-studied inconsistent information aggregation problems (e.g. rank aggregation) to probabilistic databases. We consider this problem for various types of queries including SPJ queries, Top-k ranking queries, group-by aggregate queries, and clustering. For different distance metrics, we obtain polynomial time optimal or approximation algorithms for computing the consensus answers (or prove NP-hardness). Most of our results are for a general probabilistic database model, called and/xor tree model, which significantly generalizes previous probabilistic database models like x-tuples and block-independent disjoint models, and is of independent interest.
Keywords: consensus answers; probabilistic and/xor tree; Probabilistic databases; Query processing; rank aggregation

A cooperative combinatorial Particle Swarm Optimization algorithm for side-chain packing - Lapizco-Encinas,G.; Kingsford, Carl; Reggia, James A. (IEEE Swarm Intelligence Symposium, 2009. SIS '09, 2009)
Particle Swarm Optimization (PSO) is a well-known, competitive technique for numerical optimization with real-parameter representation. This paper introduces CCPSO, a new Cooperative Particle Swarm Optimization algorithm for combinatorial problems. The cooperative strategy is achieved by splitting the candidate solution vector into components, where each component is optimized by a particle. Particles move throughout a continuous space, their movements based on the influences exerted by static particles that then get feedback based on the fitness of the candidate solution. Here, the application of this technique to side-chain packing (a proteomics optimization problem) is investigated. To verify the efficiency of the proposed CCPSO algorithm, we test our algorithm on three side-chain packing problems and compare our results with the provably optimal result. Computational results show that the proposed algorithm is very competitive, obtaining a conformation with an energy value within 1% of the provably optimal solution in many proteins.
Keywords: Algorithm design and analysis; Amino acids; combinatorial mathematics; cooperative combinatorial particle swarm optimization algorithm; Design optimization; Encoding; Feedback; numerical optimization; Optimization methods; particle swarm optimisation; Particle swarm optimization; Partitioning algorithms; Proteins; proteomics; proteomics optimization; Robustness; side-chain packing

A cost-effective lexical acquisition process for large-scale thesaurus translation - Jimmy Lin; Murray,G. C; Dorr, Bonnie J; Hajič,J.; Pecina,P. (Language resources and evaluation, 2009)
Thesauri and controlled vocabularies facilitate access to digital collections by explicitly representing the underlying principles of organization. Translation of such resources into multiple languages is an important component for providing multilingual access. However, the specificity of vocabulary terms in most thesauri precludes fully-automatic translation using general-domain lexical resources. In this paper, we present an efficient process for leveraging human translations to construct domain-specific lexical resources. This process is illustrated on a thesaurus of 56,000 concepts used to catalog a large archive of oral histories. We elicited human translations on a small subset of concepts, induced a probabilistic phrase dictionary from these translations, and used the resulting resource to automatically translate the rest of the thesaurus. Two separate evaluations demonstrate the acceptability of the automatic translations and the cost-effectiveness of our approach.

The Curse of Zipf and Limits to Parallelization: A Look at the Stragglers Problem in MapReduce - Jimmy Lin (Proceedings of LSDS-IR workshop, 2009)
This paper explores the problem of “stragglers” in Map-Reduce: a common phenomenon where a small number of mappers or reducers takes significantly longer than the oth- ers to complete. The effects of these stragglers include un- necessarily long wall-clock running times and sub-optimal cluster utilization. In many cases, this problem cannot sim- ply be attributed to hardware idiosyncrasies, but is rather caused by the Zipfian distribution of input or intermedi- ate data. I present a simple theoretical model that shows how such distributions impose a fundamental limit on the amount of parallelism that can be extracted from a large class of algorithms where all occurrences of the same ele- ment must be processed together. A case study in parallel ad hoc query evaluation highlights the severity of the strag- glers problem. Fortunately, a simple modification of the in- put data cuts end-to-end running time in half. This example illustrates some of the issues associated with designing effi- cient MapReduce algorithms for real-world datasets.

A Decoupled and Prioritized Stochastic Dynamic Programming Approach for Automated Transport of Multiple Particles Using Optical Tweezers - Banerjee,Ashis Gopal; Losert,Wolfgang; Gupta, Satyandra K. (ASME, 2009)
Automated transport of multiple particles using optical tweezers requires the use of motion planning to move them simultaneously while avoiding collisions amongst themselves and with randomly moving obstacles. This paper develops a decoupled and prioritized stochastic dynamic programming based motion planning framework by sequentially applying a partially observable Markov decision process algorithm on every particle that needs to be transported. An iterative version of a maximum bipartite graph matching algorithm is used to assign given goal locations to such particles. The algorithm for individual particle transport is validated using silica beads in a holographic tweezer set-up. Once the individual plans are computed, a three-step method consisting of clustering, classification, and branch and bound optimization is employed to determine the final collision-free paths. Simulation results in the form of sample trajectories and performance characterization plots are presented to illustrate the usefulness of the developed approach.

Design of data warehouse in teaching state based on OLAP and data mining - Zhou,L.; Wu,M.; Li,S. (Proceedings of SPIE, 2009)
The data warehouse and the data mining technology is one of information technology research hot topics. Atpresent the data warehouse and the data mining technology in aspects and so on commercial, financial industry as well as enterprise's production, market marketing obtained the widespread application, but is relatively less in educational fields' application. Over the years, the teaching and management have been accumulating large amounts of data in colleges and universities, while the data can not be effectively used, in the light of social needs of the university development and the current status of data management, the establishment of data warehouse in university state, the better use of existing data, and on the basis dealing with a higher level of disposal --data mining are particularly important. In this paper, starting from the decision-making needs design data warehouse structure of university teaching state, and then through the design structure and data extraction, loading, conversion create a data warehouse model, finally make use of association rule mining algorithm for data mining, to get effective results applied in practice. Based on the data analysis and mining, get a lot of valuable information, which can be used to guide teaching management, thereby improving the quality of teaching and promoting teaching devotion in universities and enhancing teaching infrastructure. At the same time it can provide detailed, multi-dimensional information for universities assessment and higher education research.

Designing Enforceable Network Contracts - Lychev,R.; Feamster, Nick (School of Computer Science, Georgia Tech, 2009)
Internet connectivity depends on contractual agreements between cooperating entities, such as administrative domains (AD), where an agreement over a certain level of service is made. Contracts (e.g., SLAs) for providing certain levels of service must be enforceable, and ADs must have an incentive to meet their contractual obligations. Previous work has designed mechanisms for both pricing and network accountability, but no existing work examines contract structures with respect to different accountability frameworks, and how together they may affect an AD’s incentives to fulfill contracts. We study how different contract structures—in particular, path-based versus pairwise contracts—affect ADs’ incentives to establish contracts (which, in turn, can affect overall connectivity) and, once contracts are established, to forward traffic according accordingly. This paper presents several contributions. First, we derive sufficient conditions for path-based contract systems and accountability frameworks for entities to have an incentive to forward traffic according to their contracts, provided that all parties involved are rational. Second, we show that for path-based contracts at equilibrium where nodes are encouraged to fulfill their contracts, only a constant amount of monitoring is required for every participant to make a positive profit; this is not the case for pairwise contracts. Third, we show how systems that rely on pairwise contracts are prone to depeering in presence of sufficient supply and demand due to coarse granularity, a contractual failure that systems which rely on path-based contracts are immune to. We propose modifications to pairwise contracts that could prevent such failures. Finally, we present situations of depeering that may be unpreventable due to maliciously behaving parties for both pairwise and path-based contract structures. For such scenarios, we show that while path-based contracts allow the sender of traffic to get reimbursed, this is not guaranteed in pairwise contract systems.

The emergence of zoning policy games in exurban jurisdictions: Informing collective action theory - Zellner,Moira L.; Page,Scott E.; Rand, William; Brown,Daniel G.; Robinson,Derek T.; Nassauer,Joan; Low,Bobbi (Land Use Policy, 2009)
Theoretical urban policy literature predicts the likelihood of free riding in the management of common goods such as forested open space; such outcome is often characterized as a Prisoner's Dilemma game. Numerous cases exist in which neighboring jurisdictions cooperate to maintain public goods, challenging the expected results, yet theoretical explanations of these cases have not been fully developed. In this paper, we use an agent-based model to explore how underlying micro-behaviors affect the payoffs obtained by two neighboring municipalities in a hypothetical exurban area. Payoffs are measured in terms of regional forested space and of local tax revenue at the end of the agent-based simulations; the municipalities affect these payoffs through their choice of residential zoning policies and the spillover effect between the neighboring jurisdictions. Zoning restrictions influence the conversion of farmland into residential subdivisions of different types, and consequently the location of heterogeneous residential households in the region. Developers and residents respond to the changing landscape characteristics, thus establishing a feedback between early and future land-use patterns. The structure of the simulated payoffs is analyzed using standard game theory. Our analysis shows that a variety of games, in addition to Prisoner's Dilemma, can emerge between the neighboring jurisdictions. Other games encourage coordination or subsidization, offering some explanations for the unexpected observations. The game realized in any given context depends on the initial characteristics of the landscape, the value given to the objectives each township seeks to maximize, and the income distribution of the population.
Keywords: Agent-based modeling; game theory; Land-use policy; Local government cooperation; Scale interaction

Enabling search over encrypted multimedia databases - Lu,W.; Swaminathan,A.; Varna,A.L.; Wu,M. (SPIE/IS&T Media Forensics and Security, 2009)
Performing information retrieval tasks while preserving data confidentiality is a desirable capability when adatabase is stored on a server maintained by a third-party service provider. This paper addresses the problem of enabling content-based retrieval over encrypted multimedia databases. Search indexes, along with multimedia documents, are first encrypted by the content owner and then stored onto the server. Through jointly apply- ing cryptographic techniques, such as order preserving encryption and randomized hash functions, with image processing and information retrieval techniques, secure indexing schemes are designed to provide both privacy protection and rank-ordered search capability. Retrieval results on an encrypted color image database and se- curity analysis of the secure indexing schemes under different attack models show that data confidentiality can be preserved while retaining very good retrieval performance. This work has promising applications in secure multimedia management.

Enhanced force measurement techniques to extend optical trapping towards nanoscale manipulation - Balijepalli,A.; LeBrun,T. W.; Gorman,J. J.; Gupta,S.K. (2009)
We have developed a new force measurement technique based on the random thermal motion of a nanoparticle in an optical trap. We demonstrate this method, in one-dimension, through numerical simulations and laboratory experiments. We show that computer simulations successfully recover the profile of the optical trapping force, beyond the inflection point of the trapping potential for a range of particle sizes. We show, through laboratory experiments, that this technique is effective in recovering higher order terms, in a power series expansion of the trapping force, beyond the widely reported linear trap stiffness. We also show that the first order (stiffness) term in our series expansion is consistent with values reported in the literature.
Keywords: Brownian motion; extend optical trapping; Fokker-Planck equation; force measurement; inflection point; linear trap stiffness; nanoparticle; nanoparticles; nanoscale manipulation; nanotechnology; optical trapping force; power series expansion; radiation pressure; random thermal motion

Evidence for Bidentate Substrate Binding as the Basis for the K48 Linkage Specificity of Otubain 1 - Wang,Tao; Yin,Luming; Cooper,Eric M.; Lai,Ming-Yih; Dickey,Seth; Pickart,Cecile M.; Fushman, David; Wilkinson,Keith D.; Cohen,Robert E.; Wolberger,Cynthia (Journal of Molecular Biology, 2009)
Otubain 1 belongs to the ovarian tumor (OTU) domain class of cysteine protease deubiquitinating enzymes. We show here that human otubain 1 (hOtu1) is highly linkage-specific, cleaving Lys48 (K48)-linked polyubiquitin but not K63-, K29-, K6-, or K11-linked polyubiquitin, or linear α-linked polyubiquitin. Cleavage is not limited to either end of a polyubiquitin chain, and both free and substrate-linked polyubiquitin are disassembled. Intriguingly, cleavage of K48-diubiquitin by hOtu1 can be inhibited by diubiquitins of various linkage types, as well as by monoubiquitin. NMR studies and activity assays suggest that both the proximal and distal units of K48-diubiquitin bind to hOtu1. Reaction of Cys23 with ubiquitin-vinylsulfone identified a ubiquitin binding site that is distinct from the active site, which includes Cys91. Occupancy of the active site is needed to enable tight binding to the second site. We propose that distinct binding sites for the ubiquitins on either side of the scissile bond allow hOtu1 to discriminate among different isopeptide linkages in polyubiquitin substrates. Bidentate binding may be a general strategy used to achieve linkage-specific deubiquitination.
Keywords: deubiquitination; isopeptide; linkage specificity; otubain; polyubiquitin

Evidence for Coregulation of Myocardial Gene Expression by MEF2 and NFAT in Human Heart Failure / CLINICAL PERSPECTIVE - Putt,Mary E.; Hannenhalli, Sridhar; Lu,Yun; Haines,Philip; Chandrupatla,Hareesh R.; Morrisey,Edward E.; Margulies,Kenneth B.; Cappola,Thomas P. (Circulation: Cardiovascular Genetics, 2009)
Background— Pathological stresses induce heart failure in animal models through activation of multiple cardiac transcription factors (TFs) working cooperatively. However, interactions among TFs in human heart failure are less understood. Here, we use genomic data to examine the evidence that 5 candidate TF families coregulate gene expression in human heart failure.Methods and Results— RNA isolates from failing (n=86) and nonfailing (n=16) human hearts were hybridized with Affymetrix HU133A arrays. For each gene on the array, we determined conserved MEF2, NFAT, NKX , GATA , and FOX binding motifs within the −1-kb promoter region using human-murine sequence alignments and the TRANSFAC database. Across 9076 genes expressed in the heart, TF-binding motifs tended to cluster together in nonrandom patterns within promoters of specific genes (P values ranging from 10−2 to 10−21), suggesting coregulation. We then modeled differential expression as a function of TF combinations present in promoter regions. Several combinations predicted increased odds of differential expression in the failing heart, with the highest odds ratios noted for genes containing both MEF2 and NFAT binding motifs together in the same promoter region (peak odds ratio, 3.47; P=0.005).Conclusions— These findings provide genomic evidence for coregulation of myocardial gene expression by MEF2 and NFAT in human heart failure. In doing so, they extend the paradigm of combinatorial regulation of gene expression to the human heart and identify new target genes for mechanistic study. More broadly, we demonstrate how integrating diverse sources of genomic data yields novel insight into human cardiovascular disorders.

Fast and Accurate Method of Uniform-colored Video Text Extraction - Shen,R.D.; Li,S.F.; Zhuolin Jiang (Jisuanji Gongcheng/ Computer Engineering, 2009)
For most video text is rich in edge,uniform-colored and horizontally ranged,the candidate text areas in video image are determined by using a fast deriche edge based algorithm,and the accurate binary text images are extracted from the areas by using a color based algorithm.The experimental results show that the method is effective in text extraction in complex-background video frame,and has higher processing speed and better extraction result in comparison with color alone based method.

Fast concurrent object localization and recognition - Tom Yeh; Lee,J.J.; Darrell,T. (Computer Vision and Pattern Recognition, 2009. CVPR 2009. IEEE Conference on, 2009)
Object localization and recognition are important problems in computer vision. However, in many applications, exhaustive search over all object models and image locations is computationally prohibitive. While several methods have been proposed to make either recognition or localization more efficient, few have dealt with both tasks simultaneously. This paper proposes an efficient method for concurrent object localization and recognition based on a data-dependent multi-class branch-and-bound formalism. Existing bag-of-features recognition techniques which can be expressed as weighted combinations of feature counts can be readily adapted to our method. We present experimental results that demonstrate the merit of our algorithm in terms of recognition accuracy, localization accuracy, and speed, compared to baseline approaches including exhaustive search, implicit-shape model (ISM), and efficient sub-window search (ESS). Moreover, we develop two extensions to consider non-rectangular bounding regions-composite boxes and polygons-and demonstrate their ability to achieve higher recognition scores compared to traditional rectangular bounding boxes.

Gene Profiling of Human Adipose Tissue During Evoked Inflammation In Vivo - Shah,Rachana; Lu,Yun; Hinkle,Christine C; McGillicuddy,Fiona C; Kim,Roy; Hannenhalli, Sridhar; Cappola,Thomas P.; Heffron,Sean; Wang,XingMei; Mehta,Nehal N; Putt,Mary; Reilly,Muredach P (DiabetesDiabetes, 2009)
OBJECTIVE Adipose inflammation plays a central role in obesity-related metabolic and cardiovascular complications. However, few human adipose-secreted proteins are known to mediate these processes. We hypothesized that microarray mRNA profiling of human adipose during evoked inflammation could identify novel adipocytokines.RESEARCH DESIGN AND METHODS Healthy human volunteers (n = 14) were treated with intravenous endotoxin (3 ng/kg lipopolysaccharide [LPS]) and underwent subcutaneous adipose biopsies before and after LPS. On Affymetrix U133Plus 2.0 arrays, adipose mRNAs modulated >1.5-fold (with P < 0.00001) were selected. SignalP 3.0 and SecretomeP 2.0 identified genes predicted to encode secreted proteins. Of these, 86 candidates were chosen for validation in adipose from an independent human endotoxemia protocol (N = 7, with 0.6 ng/kg LPS) and for exploration of cellular origin in primary human adipocytes and macrophages in vitro. RESULTS Microarray identified 776 adipose genes modulated by LPS; 298 were predicted to be secreted. Of detectable prioritized genes, 82 of 85 (96% [95% CI 90–99]) were upregulated (fold changes >1.0) during the lower-dose (LPS 0.6 ng/kg) validation study and 51 of 85 (59% [49–70]) were induced greater than 1.5-fold. Treatment of primary adipocytes with LPS and macrophage polarization to M1 proinflammatory phenotype increased expression by 1.5-fold for 58 and 73% of detectable genes, respectively. CONCLUSIONS We demonstrate that evoked inflammation of human adipose in vivo modulated expression of multiple genes likely secreted by adipocytes and monocytes. These included established adipocytokines and chemokines implicated in recruitment and activation of lymphocytes, adhesion molecules, antioxidants, and several novel genes with unknown function. Such candidates may represent biomarkers and therapeutic targets for obesity-related complications.

Generating simplified trapping probability models from simulation of optical tweezers system - Banerjee,A. G.; Balijepalli,A.; Gupta,S.K.; LeBrun,T. W. (Journal of Computing and Information Science in Engineering, 2009)

Genome assortment, not serogroup, defines Vibrio cholerae pandemic strains - Brettin,Thomas S[Los Alamos National Laboratory; Bruce,David C[Los Alamos National Laboratory; Challacombe,Jean F[Los Alamos National Laboratory; Detter,John C[Los Alamos National Laboratory; Han,Cliff S[Los Alamos National Laboratory; Munik,A. C[Los Alamos National Laboratory; Chertkov,Olga[Los Alamos National Laboratory; Meincke,Linda[Los Alamos National Laboratory; Saunders,Elizabeth[Los Alamos National Laboratory; Choi,Seon Y[SEOUL NATL UNIV; Haley,Bradd J[U MARYLAND; Taviani,Elisa[U MARYLAND; et al. (Nature, 2009)
Vibrio cholerae, the causative agent of cholera, is a bacterium autochthonous to the aquatic environment, and a serious public health threat. V. cholerae serogroup O1 is responsible for the previous two cholera pandemics, in which classical and El Tor biotypes were dominant in the 6th and the current 7th pandemics, respectively. Cholera researchers continually face newly emerging and re-emerging pathogenic clones carrying combinations of new serogroups as well as of phenotypic and genotypic properties. These genotype and phenotype changes have hampered control of the disease. Here we compare the complete genome sequences of 23 strains of V. cholerae isolated from a variety of sources and geographical locations over the past 98 years in an effort to elucidate the evolutionary mechanisms governing genetic diversity and genesis of new pathogenic clones. The genome-based phylogeny revealed 12 distinct V. cholerae phyletic lineages, of which one, designated the V. cholerae core genome (CG), comprises both O1 classical and EI Tor biotypes. All 7th pandemic clones share nearly identical gene content, i.e., the same genome backbone. The transition from 6th to 7th pandemic strains is defined here as a 'shift' between pathogenic clones belonging to the same O1 serogroup, but from significantly different phyletic lineages within the CG clade. In contrast, transition among clones during the present 7th pandemic period can be characterized as a 'drift' between clones, differentiated mainly by varying composition of laterally transferred genomic islands, resulting in emergence of variants, exemplified by V.cholerae serogroup O139 and V.cholerae O1 El Tor hybrid clones that produce cholera toxin of classical biotype. Based on the comprehensive comparative genomics presented in this study it is concluded that V. cholerae undergoes extensive genetic recombination via lateral gene transfer, and, therefore, genome assortment, not serogroup, should be used to define pathogenic V. cholerae clones.
Keywords: 59; CHOLERA; GENES; GENETICS; GENOTYPE; ISLANDS; ORIGIN; PHENOTYPE; PUBLIC HEALTH; RECOMBINATION; STRAINS; TOXINS

Hat guessing games - Butler,S.; Hajiaghayi, Mohammad T.; Kleinberg,R. D; Leighton,T. (SIAM review, 2009)

HydroSense: infrastructure-mediated single-point sensing of whole-home water activity - Jon Froehlich; Larson,E.; Campbell,T.; Haggerty,C.; Fogarty,J.; Patel,S.N. (Proceedings of the 11th international conference on Ubiquitous computing, September, 2009)

Interacting with eHealth: towards grand challenges for HCI - André,P.; White,R.; Tan,D.; Berners-Lee,T.; Consolvo,S.; Jacobs,R.; Kohane,I.; Le Dantec,C.A.; Mamykina,L.; Marsden,G. (Proceedings of the 27th international conference extended abstracts on Human factors in computing systems, 2009)
While health records are increasingly stored electronically, we, as citizens, have little access to this data about ourselves. We are not used to thinking of these official records either as ours or as useful to us. We increasingly turn to the Web, however, to query any ache, pain or health goal we may have before consulting with health care professionals. Likewise, for proactive health care such as nutrition or fitness, or to find fellow-sufferers for post diagnosis support, we turn to online resources. There is a potential disconnect between points at which professional and lay eHealth data and resources intersect for preventative or proactive health care. Such gaps in information sharing may have direct impact on practices we decide to take up, the care we seek, or the support professionals offer. In this panel, we consider several places within proactive, preventative health care in particular HCI has a role towards enhancing health knowledge discovery and health support interaction. Our goal is to demonstrate how now is the time for eHealth to come to the forefront of the HCI research agenda.

Interlingual annotation of multilingual text corpora and FrameNet - Farwell,David; Dorr, Bonnie J; Habash,Nizar; Helmreich,Stephen; Hovy,Eduard; Green,Rebecca; Levin,Lori; Miller,Keith; Mitamura,Teruko; Rambow,Owen; Reeder,Flo; Siddharthan,Advaith (Multilingual FrameNets in Computational LexicographyMultilingual FrameNets in Computational Lexicography, 2009)

Language Identification for Handwritten Document Images Using AShape Codebook - Zhu,Guangyu; Yu,Xiaodong; Li,Yi; David Doermann (Pattern Recognition, 2009)
Language identification for handwritten document images is an open document analysis problem. In this paper, we propose a novel approach to language identification for documents containing mixture of handwritten and machine printed text using image descriptors constructed from a codebook of shape features. We encode local text structures using scale and rotation invariant codewords, each representing a segmentation-free shape feature that is generic enough to be detected repeatably. We learn a concise, structurally indexed shape codebook from training by clustering and partitioning similar feature types through graph cuts. Our approach is easily extensible and does not require skew correction, scale normalization, or segmentation. We quantitatively evaluate our approach using a large real-world document image collection, which is composed of 1,512 documents in eight languages (Arabic, Chinese, English, Hindi, Japanese, Korean, Russian, and Thai) and contains a complex mixture of handwritten and machine printed content. Experiments demonstrate the robustness and flexibility of our approach, and show exceptional language identification performance that exceeds the state of the art.

Learning multi-modal densities on Discriminative Temporal Interaction Manifold for group activity recognition - Ruonan Li; Chellapa, Rama; Zhou,S. K (Computer Vision and Pattern Recognition, 2009. CVPR 2009. IEEE Conference on, 2009)
While video-based activity analysis and recognition has received much attention, existing body of work mostly deals with single object/person case. Coordinated multi-object activities, or group activities, present in a variety of applications such as surveillance, sports, and biological monitoring records, etc., are the main focus of this paper. Unlike earlier attempts which model the complex spatial temporal constraints among multiple objects with a parametric Bayesian network, we propose a Discriminative Temporal Interaction Manifold (DTIM) framework as a data-driven strategy to characterize the group motion pattern without employing specific domain knowledge. In particular, we establish probability densities on the DTIM, whose element, the discriminative temporal interaction matrix, compactly describes the coordination and interaction among multiple objects in a group activity. For each class of group activity we learn a multi-modal density function on the DTIM. A Maximum a Posteriori (MAP) classifier on the manifold is then designed for recognizing new activities. Experiments on football play recognition demonstrate the effectiveness of the approach.
Keywords: a; activities; parametric; activity; analysis; belief; analysis; pattern; Bayesian; classification; image; classifier; multimodal; complex; constraints; data-driven; density; equipment; video; function; multiobject; interaction; manifold; discriminative; matrix; football; MOTION; network; video-based; networks; image; play; posteriori; processing; recognition; recognition; group; recognition; maximum; signal; spatial; strategy; discriminative; temporal

The Maryland Modular Method: An Approach to Doctoral Education in Information Studies - Druin, Allison; Jaeger,P. T; Golbeck,J.; Fleischmann,K.R.; Jimmy Lin; Qu,Y.; Wang,P.; Xie,B. (Journal of education for library and information science, 2009)

Measuring General Relational Structure Using the Block Modularity Clustering Objective - Anthony,Adam Paul; desJardins, Marie; Lombardi,Michael (Twenty-Second International FLAIRS Conference, 2009)
The performance of all relational learning techniques has an implicit dependence on the underlying connectivity structure of the relations that are used as input. In this paper, we show how clustering can be used to develop an efficient optimization strategy can be used to effectively measure the structure of a graph in the absence of labeled instances.

Minimizing Communication Cost in Distributed Multi-query Processing - Li,Jian; Deshpande, Amol; Khuller, Samir (IEEE 25th International Conference on Data Engineering, 2009. ICDE '09, 2009)
Increasing prevalence of large-scale distributed monitoring and computing environments such as sensor networks, scientific federations, Grids etc., has led to a renewed interest in the area of distributed query processing and optimization. In this paper we address a general, distributed multi-query processing problem motivated by the need to minimize the communication cost in these environments. Specifically we address the problem of optimally sharing data movement across the communication edges in a distributed communication network given a set of overlapping queries and query plans for them (specifying the operations to be executed). Most of the problem variations of our general problem can be shown to be NP-Hard by a reduction from the Steiner tree problem. However, we show that the problem can be solved optimally if the communication network is a tree, and present a novel algorithm for finding an optimal data movement plan. For general communication networks, we present efficient approximation algorithms for several variations of the problem. Finally, we present an experimental study over synthetic datasets showing both the need for exploiting the sharing of data movement and the effectiveness of our algorithms at finding such plans.
Keywords: Approximation algorithms; Communication networks; Computer science; Cost function; Data engineering; distributed communication network; distributed databases; distributed multi-query processing; grid computing; Large-scale systems; NP-hard; optimisation; Polynomials; Publish-subscribe; publish-subscribe systems; Query optimization; Query processing; sensor networks; Steiner tree problem; Tree graphs; trees (mathematics)

Modeling actions of PubMed users with n-gram language models - Jimmy Lin; Wilbur,W. J (Information retrieval, 2009)
Transaction logs from online search engines are valuable for two reasons: First, they provide insight into human information-seeking behavior. Second, log data can be used to train user models, which can then be applied to improve retrieval systems. This article presents a study of logs from PubMed®, the public gateway to the MEDLINE® database of bibliographic records from the medical and biomedical primary literature. Unlike most previous studies on general Web search, our work examines user activities with a highly-specialized search engine. We encode user actions as string sequences and model these sequences using n-gram language models. The models are evaluated in terms of perplexity and in a sequence prediction task. They help us better understand how PubMed users search for information and provide an enabler for improving users’ search experience.

Motifs and cis-regulatory modules mediating the expression of genes co-expressed in presynaptic neurons - Liu,Rui; Hannenhalli, Sridhar; Bucan,Maja (Genome Biology, 2009)
Hundreds of proteins modulate neurotransmitter release and synaptic plasticity during neuronal development and in response to synaptic activity. The expression of genes in the pre- and post-synaptic neurons is under stringent spatio-temporal control, but the mechanism underlying the neuronal expression of these genes remains largely unknown.

Multiple instance Feature for robust part-based object detection - Lin,Z.; Hua,G.; Davis, Larry S. (Computer Vision and Pattern Recognition, 2009. CVPR 2009. IEEE Conference on, 2009)

Pairwise Document Similarity in Large Collections with MapReduce - Elsayed,T.; Jimmy Lin; Oard, Douglas (Relation, 2009)

Predicting the distribution of Vibrio spp. in the Chesapeake Bay: a Vibrio cholerae case study - Constantin de Magny,G.; Long,W.; Brown,C. W.; Hood,R. R.; Huq,A.; Murtugudde,R.; Rita R Colwell (EcoHealth, 2009)
Vibrio cholerae, the causative agent of cholera, is a naturally occurring inhabitant of the Chesapeake Bay and serves as a predictor for other clinically important vibrios, including Vibrio parahaemolyticus and Vibrio vulnificus. A system was constructed to predict the likelihood of the presence of V. cholerae in surface waters of the Chesapeake Bay, with the goal to provide forecasts of the occurrence of this and related pathogenic Vibrio spp. Prediction was achieved by driving an available multivariate empirical habitat model estimating the probability of V. cholerae within a range of temperatures and salinities in the Bay, with hydrodynamically generated predictions of ambient temperature and salinity. The experimental predictions provided both an improved understanding of the in situ variability of V. cholerae, including identification of potential hotspots of occurrence, and usefulness as an early warning system. With further development of the system, prediction of the probability of the occurrence of related pathogenic vibrios in the Chesapeake Bay, notably V. parahaemolyticus and V. vulnificus, will be possible, as well as its transport to any geographical location where sufficient relevant data are available.

Real-time shape retrieval for robotics using skip Tri-Grams - Li,Yi; Bitsakos,K.; Fermüller, Cornelia; Aloimonos, J. (IEEE/RSJ International Conference on Intelligent Robots and Systems, 2009. IROS 2009, 2009)
The real time requirement is an additional constraint on many intelligent applications in robotics, such as shape recognition and retrieval using a mobile robot platform. In this paper, we present a scalable approach for efficiently retrieving closed contour shapes. The contour of an object is represented by piecewise linear segments. A skip Tri-Gram is obtained by selecting three segments in the clockwise order while allowing a constant number of segments to be ÃÂ¿skippedÃÂ¿ in between. The main idea is to use skip Tri-Grams of the segments to implicitly encode the distant dependency of the shape. All skip Tri-Grams are used for efficiently retrieving closed contour shapes without pairwise matching feature points from two shapes. The retrieval is at least an order of magnitude faster than other state-of-the-art algorithms. We score 80% in the Bullseye retrieval test on the whole MPEG 7 shape dataset. We further test the algorithm using a mobile robot platform in an indoor environment. 8 objects are used for testing from different viewing directions, and we achieve 82% accuracy.
Keywords: Bullseye retrieval test; Clocks; closed contour shape retrieval; Image retrieval; Image segmentation; Indexing; Information retrieval; Intelligent robots; Jacobian matrices; mobile robot; Mobile robots; MPEG 7 shape dataset; piecewise linear segments; Piecewise linear techniques; Real time systems; real-time shape retrieval; robot vision; SHAPE; shape recognition; shape representation; skip Tri-Grams; Testing

Recognizing actions by shape-motion prototype trees - Zhe Lin; Zhuolin Jiang; Davis, Larry S. (Computer Vision, 2009 IEEE 12th International Conference on, 2009)
A prototype-based approach is introduced for action recognition. The approach represents an action as a sequence of prototypes for efficient and flexible action matching in long video sequences. During training, first, an action prototype tree is learned in a joint shape and motion space via hierarchical k-means clustering; then a lookup table of prototype-to-prototype distances is generated. During testing, based on a joint likelihood model of the actor location and action prototype, the actor is tracked while a frame-to-prototype correspondence is established by maximizing the joint likelihood, which is efficiently performed by searching the learned prototype tree; then actions are recognized using dynamic prototype sequence matching. Distance matrices used for sequence matching are rapidly obtained by look-up table indexing, which is an order of magnitude faster than brute-force computation of frame-to-frame distances. Our approach enables robust action matching in very challenging situations (such as moving cameras, dynamic backgrounds) and allows automatic alignment of action sequences. Experimental results demonstrate that our approach achieves recognition rates of 91.07% on a large gesture dataset (with dynamic backgrounds), 100% on the Weizmann action dataset and 95.77% on the KTH action dataset.

Recognizing coordinated multi-object activities using a dynamic event ensemble model - Ruonan Li; Chellapa, Rama (Acoustics, Speech and Signal Processing, 2009. ICASSP 2009. IEEE International Conference on, 2009)
While video-based activity analysis and recognition has received broad attention, existing body of work mostly deals with single object/person case. Modeling involving multiple objects and recognition of coordinated group activities, present in a variety of applications such as surveillance, sports, biological records, and so on, is the main focus of this paper. Unlike earlier attempts which model the complex spatial temporal constraints among different activities of multiple objects with a parametric Bayesian network, we propose a dynamic dasiaevent ensemblepsila framework as a data-driven strategy to characterize the group motion pattern without employing any specific domain knowledge. In particular, we exploit the Riemannian geometric property of the set of ensemble description functions and develop a compact representation for group activities on the ensemble manifold. An appropriate classifier on the manifold is then designed for recognizing new activities. Experiments on football play recognition demonstrate the effectiveness of the framework.
Keywords: activities; activity; analysis; Bayes; Bayesian; classification; video; description; ensemble; event; framework; dynamic; functions; ensemble; geometric; manifold; football; methods; geometry; image; model; ensemble; multiobject; network; video-based; play; processing; property; classifier; coordinated; recognition; data-driven; recognition; parametric; Riemannian; signal; strategy; dynamic

Recovering Views of Inter-System Interaction Behaviors - Ackermann,Christopher; Lindvall,Mikael; Cleaveland, Rance (Reverse Engineering, Working Conference on, 2009)
This paper presents an approach for recovering application-level views of the interaction behaviors between systems that communicate via networks. Rather than illustrating a single behavior, a sequence diagram is constructed that describes the characteristics of multiple combined behaviors. The approach has several properties that make it particularly suitable for analyzing heterogeneous systems. First, since the interactions are retrieved from observing the network communication, our technique can be applied to systems that are implemented in different languages and run on different platforms. Second, it does not require the availability or modification of source code. After the behaviors are extracted, we employ methods to merge multiple observed behaviors to a single sequence diagram that illustrates the overall behavior.The contributions of this paper are a technique for observing and processing the network communication to derive a model of the behavior. Furthermore, it describes a series of model transformations to construct a sequence diagram view of all observed behaviors.
Keywords: distributed systems; program understanding; reliability

Resistin gene variation is associated with systemic inflammation but not plasma adipokine levels, metabolic syndrome or coronary atherosclerosis in nondiabetic Caucasians - Qasim,Atif N; Metkus,Thomas S; Tadesse,Mahlet; Lehrke,Michael; Restine,Stephanie; Wolfe,Megan L; Hannenhalli, Sridhar; Cappola,Thomas; Rader,Daniel J; Reilly,Muredach P (Clinical Endocrinology, 2009)
Objective  Resistin causes insulin resistance and diabetes in mice whereas in humans it is linked to inflammation and atherosclerosis. Few human genetic studies of resistin in inflammation and atherosclerosis have been performed. We hypothesized that the –420C>G putative gain-of-function resistin variant would be associated with inflammatory markers and atherosclerosis but not with metabolic syndrome or adipokines in humans.Design and methods  We examined the association of three resistin polymorphisms, –852A>G, –420C>G and +157C>T, and related haplotypes with plasma resistin, cytokines, C-reactive protein (CRP), adipokines, plasma lipoproteins, metabolic syndrome and coronary artery calcification (CAC) in nondiabetic Caucasians (n = 851). Results  Resistin levels were higher, dose-dependently, with the –420G allele (CC 5·9 ± 2·7 ng/ml, GC 6·5 ± 4·0 ng/ml and GG 7·2 ± 4·8 ng/ml, trend P = 0·04) after age and gender adjustment [fold higher for GC + GG vs. CC; 1·07 (1·00–1·15), P < 0·05)]. The –852A>G single nucleotide polymorphism (SNP) was associated with higher soluble tumour necrosis factor-receptor 2 (sol-TNFR2) levels in fully adjusted models [1·06 (95% CI 1·01–1·11), P = 0·01)]. The estimated resistin haplotype (GGT) was associated with sol-TNFR2 (P = 0·04) and the AGT haplotype was related to CRP (P = 0·04) in the fully adjusted models. Resistin SNPs and haplotypes were not associated with body mass index (BMI), fasting glucose, insulin resistance, metabolic syndrome, adipokines or CAC scores. Conclusions  Despite modest associations with plasma resistin and inflammatory biomarkers, resistin 5′ variants were not associated with metabolic parameters or coronary calcification. This suggests that resistin is an inflammatory cytokine in humans but has little influence on adiposity, metabolic syndrome or atherosclerosis.

Saliency-guided lighting - Lee,C. H; Kim,Y.; Varshney, Amitabh (IEICE TRANSACTIONS on Information and Systems, 2009)

Scene it or not? incremental multiple kernel learning for object detection - Kembhavi,A.; Siddiquie,B.; Miezianko,R.; McCloskey,S.; Davis, Larry S.; Schwartz, W.R.; Harwood,D.; Gupta,A.; Farrell,R.; Luo,Y.; others (Proceedings of the International Conference on Computer Vision, 2009)

Searching for SNPs with cloud computing - Langmead,Ben; Schatz,Michael C; Jimmy Lin; Pop, Mihai; Salzberg,Steven L. (Genome Biology, 2009)
As DNA sequencing outpaces improvements in computer speed, there is a critical need to accelerate tasks like alignment and SNP calling. Crossbow is a cloud-computing software tool that combines the aligner Bowtie and the SNP caller SOAPsnp. Executing in parallel using Hadoop, Crossbow analyzes data comprising 38-fold coverage of the human genome in three hours using a 320-CPU cluster rented from a cloud computing service for about $85. Crossbow is available from http://bowtie-bio.sourceforge.net/crossbow/.

Secure image retrieval through feature protection - Lu,Wenjun; Varna,A.L.; Swaminathan,A.; M. Wu (Acoustics, Speech and Signal Processing, 2009. ICASSP 2009. IEEE International Conference on, 2009)
This paper addresses the problem of image retrieval from an encrypted database, where data confidentiality is preserved both in the storage and retrieval process. The paper focuses on image feature protection techniques which enable similarity comparison among protected features. By utilizing both signal processing and cryptographic techniques, three schemes are investigated and compared, including bit-plane randomization, random projection, and randomized unary encoding. Experimental results show that secure image retrieval can achieve comparable retrieval performance to conventional image retrieval techniques without revealing information about image content. This work enriches the area of secure information retrieval and can find applications in secure online services for images and videos.
Keywords: bit-plane; confidentiality; data; database; image; databases; encoding; signal; extraction; image; feature; processes; visual; processing; content-based; projection; randomized; protection; image; randomization; cryptographic; retrieval; cryptography; feature; retrieval; random; storage; encrypted; technique; data; unary

Sensing opportunities for personalized feedback technology to reduce consumption - Jon Froehlich; Everitt,K.; Fogarty,J.; Patel,S.; Landay,J. (Proc. CHI Workshop on Defining the Role of HCI in the Challenge of Sustainability, 2009)

Serogroup, Virulence, and Genetic Traits of Vibrio Parahaemolyticus in the Estuarine Ecosystem of Bangladesh - Alam,Munirul; Chowdhury,Wasimul B.; Bhuiyan,N. A.; Islam,Atiqul; Hasan,Nur A.; Nair,G. Balakrish; Watanabe,H.; Siddique,A. K.; Huq,Anwar; Sack,R. Bradley; Akhter,M. Z.; Grim,Christopher J.; et al. (Applied and Environmental MicrobiologyAppl. Environ. Microbiol., 2009)
Forty-two strains of Vibrio parahaemolyticus were isolated from Bay of Bengal estuaries and, with two clinical strains, analyzed for virulence, phenotypic, and molecular traits. Serological analysis indicated O8, O3, O1, and K21 to be the major O and K serogroups, respectively, and O8:K21, O1:KUT, and O3:KUT to be predominant. The K antigen(s) was untypeable, and pandemic serogroup O3:K6 was not detected. The presence of genes toxR and tlh were confirmed by PCR in all but two strains, which also lacked toxR. A total of 18 (41%) strains possessed the virulence gene encoding thermostable direct hemolysin (TDH), and one had the TDH-related hemolysin (trh) gene, but not tdh. Ten (23%) strains exhibited Kanagawa phenomenon that surrogates virulence, of which six, including the two clinical strains, possessed tdh. Of the 18 tdh-positive strains, 17 (94%), including the two clinical strains, had the seromarker O8:K21, one was O9:KUT, and the single trh-positive strain was O1:KUT. None had the group-specific or ORF8 pandemic marker gene. DNA fingerprinting employing pulsed-field gel electrophoresis (PFGE) of SfiI-digested DNA and cluster analysis showed divergence among the strains. Dendrograms constructed using PFGE (SfiI) images from a soft database, including those of pandemic and nonpandemic strains of diverse geographic origin, however, showed that local strains formed a cluster, i.e., “clonal cluster,” as did pandemic strains of diverse origin. The demonstrated prevalence of tdh-positive and diarrheagenic serogroup O8:K21 strains in coastal villages of Bangladesh indicates a significant human health risk for inhabitants.

Shape Matching for Foliage Database Retrieval - Ling,H.; Jacobs, David W. (Semantic Mining Technologies for Multimedia DatabasesSemantic Mining Technologies for Multimedia Databases, 2009)

Sparse representation of cast shadows via ℓ1-regularized least squares - Mei,Xue; Ling,Haibin; Jacobs, David W. (Computer Vision, 2009 IEEE 12th International Conference on, 2009)
Scenes with cast shadows can produce complex sets of images. These images cannot be well approximated by low-dimensional linear subspaces. However, in this paper we show that the set of images produced by a Lambertian scene with cast shadows can be efficiently represented by a sparse set of images generated by directional light sources. We first model an image with cast shadows as composed of a diffusive part (without cast shadows) and a residual part that captures cast shadows. Then, we express the problem in an #x2113;1-regularized least squares formulation, with nonnegativity constraints. This sparse representation enjoys an effective and fast solution, thanks to recent advances in compressive sensing. In experiments on both synthetic and real data, our approach performs favorably in comparison to several previously proposed methods.
Keywords: #x2113; 1-regularized; approximations; lighting; formulation; Lambertian; least; representation; image; representation; least; scene; cast; sensing; sparse; shadows; compressive; squares

Spatio-textual spreadsheets: geotagging via spatial coherence - Lieberman,Michael D.; Samet, Hanan; Sankaranarayanan,Jagan; Sperling,Jon (Proceedings of the 17th ACM SIGSPATIAL International Conference on Advances in Geographic Information Systems, 2009)
The spatio-textual spreadsheet is a conventional spreadsheet where spatial attribute values are specified textually. Techniques are presented to automatically find the textually-specified spatial attributes that are present in spreadsheets. Once the spatial attributes have been identified, an accurate translation of the values of the spatial attributes to their actual geographic locations is needed (known as geotagging). The key observation is that spreadsheets with spatial data exhibit spatial coherence --- that is, cells with spatial data that are nearby in the spreadsheet contain data that share spatial characteristics in the real world. These techniques also allow richer search engine results by returning actual tuples from spreadsheets instead of simply links to the spreadsheets. Moreover, when the search key is a particular location, results in proximity to the query can be provided rather than just exact matches.
Keywords: geotagging; spatial coherence; spatio-textual; spreadsheets

Structure of the S5a:K48-Linked Diubiquitin Complex and Its Interactions with Rpn13 - Zhang,Naixia; Wang,Qinghua; Ehlinger,Aaron; Randles,Leah; Lary,Jeffrey W.; Kang,Yang; Haririnia,Aydin; Storaska,Andrew J.; Cole,James L.; Fushman, David; Walters,Kylie J. (Molecular Cell, 2009)
SummaryDegradation by the proteasome typically requires substrate ubiquitination. Two ubiquitin receptors exist in the proteasome, S5a/Rpn10 and Rpn13. Whereas Rpn13 has only one ubiquitin-binding surface, S5a binds ubiquitin with two independent ubiquitin-interacting motifs (UIMs). Here, we use nuclear magnetic resonance (NMR) and analytical ultracentrifugation to define at atomic level resolution how S5a binds K48-linked diubiquitin, in which K48 of one ubiquitin subunit (the “proximal” one) is covalently bonded to G76 of the other (the “distal” subunit). We demonstrate that S5a's UIMs bind the two subunits simultaneously with a preference for UIM2 binding to the proximal subunit while UIM1 binds to the distal one. In addition, NMR experiments reveal that Rpn13 and S5a bind K48-linked diubiquitin simultaneously with subunit specificity, and a model structure of S5a and Rpn13 bound to K48-linked polyubiquitin is provided. Altogether, our data demonstrate that S5a is highly adaptive and cooperative toward binding ubiquitin chains.
Keywords: Proteins

Symbiotic relationships in internet routing overlays - Lumezanu,Cristian; Baden,Randy; Levin,Dave; Spring, Neil; Bhattacharjee, Bobby (Proceedings of the 6th USENIX symposium on Networked systems design and implementation, 2009)
We propose to construct routing overlay networks using the following principle: that overlay edges should be based on mutual advantage between pairs of hosts. Upon this principle, we design, implement, and evaluate Peer-Wise, a latency-reducing overlay network. To show the feasibility of PeerWise, we must show first that mutual advantage exists in the Internet: perhaps contrary to expectation, that there are not only "haves" and "have nots" of low-latency connectivity. Second, we must provide a scalable means of finding promising edges and overlay routes; we seek embedding error in network coordinates to expose both shorter-than-default "detour" routes and longer-than-expected default routes. We evaluate the cost of limiting PeerWise to mutually advantageous links, then build the intelligent components that put PeerWise into practice. We design and evaluate "virtual" network coordinates for destinations not participating in the overlay, neighbor selection algorithms to find promising relays, and relay selection algorithms to choose the neighbor to traverse for a good detour. Finally, we show that PeerWise is practical through a wide-area deployment and evaluation.

System and method for fast illumination-invariant background subtraction ... - Lim,Ser-Nam; Mittal,Anurag; Davis, Larry S. (2009)
A method for eliminating errors in foreground object detection in digitized images comprises providing a reference camera and a secondary camera, vertically aligning each said camera with a baseline that is approximately perpendicular to a ground plane, wherein said reference camera is placed lower than said secondary camera, selecting a foreground pixel in a reference view of a first point in a foreground object, finding a conjugate pixel of the foreground pixel in a secondary view, using the foreground and conjugate pixels to determine an image base pixel of a base point in the reference view, wherein said base point is a point on the ground plane below the first point, and using the foreground and image base pixels to find a location where the ground plane is first visible.

Systems-compatible incentives - Levin,D.; Spring, Neil; Bhattacharjee, Bobby (Game Theory for Networks, 2009. GameNets '09. International Conference on, 2009)
Selfish participants in a distributed system attempt to gain from the system without regard to how their actions may affect others. To maintain desirable system-wide properties in the presence of selfish users, designers are increasingly turning to the powerful mechanisms offered by economics and game theory. Combining the two fields of economics and systems design introduces new challenges of achieving incentive-compatibility in systems we can deploy in today's Internet. In this paper, we explore the interactions between systems and the mechanisms that give users incentives to cooperate. Using findings from recent work on incentive-compatible systems, we discuss several economic mechanisms and assumptions: money, punishment, and altruism. We seek to understand when these mechanisms violate system properties. Among the potential pitfalls we present is a phenomenon we call the price of altruism: altruistic peers can impose a loss of social good in some systems. We also discuss systems-compatible mechanisms that have been used in real, distributed systems, and attempt to extract the underlying design principles that have led to their success.
Keywords: computing; incentives; game; Internet; distributed; system; distributed; systems; game; systems; systems-compatible; theory; incentive-compatible; theory; peer-to-peer

Topological ordering of function words in hierarchical phrase-based translation - Setiawan,H.; Kan,M.Y.; Li,H.; Resnik, Philip (Proceedings of the Joint Conference of the 47th Annual Meeting of the ACL and the 4th International Joint Conference on Natural Language Processing of the AFNLP: Volume 1-Volume 1, 2009)

Triangle Inequality and Routing Policy Violations in the Internet - Lumezanu,Cristian; Baden,Randy; Spring, Neil; Bhattacharjee, Bobby (Passive and Active Network MeasurementPassive and Active Network Measurement, 2009)
Triangle inequality violations (TIVs) are the effect of packets between two nodes being routed on the longer direct path between them when a shorter detour path through an intermediary is available. TIVs are a natural, widespread and persistent consequence of Internet routing policies. By exposing opportunities to improve the delay between two nodes, TIVs can help myriad applications that seek to minimize end-to-end latency. However, sending traffic along the detour paths revealed by TIVs may influence Internet routing negatively. In this paper we study the interaction between triangle inequality violations and policy routing in the Internet. We use measured and predicted AS paths between Internet nodes to show that 25% of the detour paths exposed by TIVs are in fact available to BGP but are simply deemed “less efficient”. We also compare the AS paths of detours and direct paths and find that detours use AS edges that are rarely followed by default Internet paths, while avoiding others that BGP seems to prefer. Our study is important both for understanding the various interactions that occur at the routing layer as well as their effects on applications that seek to use TIVs to minimize latency.
Keywords: Computer; Science

Triangle inequality variations in the internet - Lumezanu,Cristian; Baden,Randy; Spring, Neil; Bhattacharjee, Bobby (Proceedings of the 9th ACM SIGCOMM conference on Internet measurement conference, 2009)
Triangle inequality violations (TIVs) are important for latency sensitive distributed applications. On one hand, they can expose opportunities to improve network routing by finding shorter paths between nodes. On the other hand, TIVs can frustrate network embedding or positioning systems that treat the Internet as a metric space where the triangle inequality holds. Even though triangle inequality violations are both significant and curious, their study has been limited to aggregate data sets that combine measurements taken over long periods of time. The limitations of these data sets open crucial questions in the design of systems that exploit (or avoid) TIVs: are TIVs stable or transient? Or are they illusions caused by aggregating measurements taken at different times? We collect latency matrices at varying sizes and time granularities and study dynamic properties of triangle inequality violations in the Internet. We show that TIVs are not results of measurement error and that their number varies with time. We examine how latency aggregates of data measured over longer periods of time preserve TIVs. Using medians to compute violations eliminates most of the TIVs that appear sporadically during the measurement but it misses many of the ones that are present for more than five hours.
Keywords: latency; tiv; triangle inequality violation; variation

TwitterStand: news in tweets - Sankaranarayanan,Jagan; Samet, Hanan; Teitler,Benjamin E.; Lieberman,Michael D.; Sperling,Jon (Proceedings of the 17th ACM SIGSPATIAL International Conference on Advances in Geographic Information Systems, 2009)
Twitter is an electronic medium that allows a large user populace to communicate with each other simultaneously. Inherent to Twitter is an asymmetrical relationship between friends and followers that provides an interesting social network like structure among the users of Twitter. Twitter messages, called tweets, are restricted to 140 characters and thus are usually very focused. We investigate the use of Twitter to build a news processing system, called TwitterStand, from Twitter tweets. The idea is to capture tweets that correspond to late breaking news. The result is analogous to a distributed news wire service. The difference is that the identities of the contributors/reporters are not known in advance and there may be many of them. Furthermore, tweets are not sent according to a schedule: they occur as news is happening, and tend to be noisy while usually arriving at a high throughput rate. Some of the issues addressed include removing the noise, determining tweet clusters of interest bearing in mind that the methods must be online, and determining the relevant locations associated with the tweets.
Keywords: geotagging; news; online clustering; Twitter

UbiGreen: investigating a mobile tool for tracking and supporting green transportation habits - Jon Froehlich; Dillahunt,Tawanna; Klasnja,Predrag; Mankoff,Jennifer; Consolvo,Sunny; Harrison,Beverly; Landay,James A. (Proceedings of the 27th international conference on Human factors in computing systems, 2009)
Keywords: ambient displays; mobile phones; sensing; Sustainability; transportation; ubicomp

Ultrafast and memory-efficient alignment of short DNA sequences to the human genome - Langmead,Ben; Trapnell,Cole; Pop, Mihai; Salzberg,Steven L. (Genome Biology, 2009)
Bowtie is an ultrafast, memory-efficient alignment program for aligning short DNA sequence reads to large genomes. For the human genome, Burrows-Wheeler indexing allows Bowtie to align more than 25 million reads per CPU hour with a memory footprint of approximately 1.3 gigabytes. Bowtie extends previous Burrows-Wheeler techniques with a novel quality-aware backtracking algorithm that permits mismatches. Multiple processor cores can be used simultaneously to achieve even greater alignment speeds. Bowtie is open source http://bowtie.cbcb.umd.edu.

A unified approach to ranking in probabilistic databases - Li,Jian; Saha,Barna; Deshpande, Amol (Proceedings of the VLDB Endowment, 2009)
The dramatic growth in the number of application domains that naturally generate probabilistic, uncertain data has resulted in a need for efficiently supporting complex querying and decision-making over such data. In this paper, we present a unified approach to ranking and top-k query processing in probabilistic databases by viewing it as a multi-criteria optimization problem, and by deriving a set of features that capture the key properties of a probabilistic dataset that dictate the ranked result. We contend that a single, specific ranking function may not suffice for probabilistic databases, and we instead propose two parameterized ranking functions, called PRFω and PRFe, that generalize or can approximate many of the previously proposed ranking functions. We present novel generating functions-based algorithms for efficiently ranking large datasets according to these ranking functions, even if the datasets exhibit complex correlations modeled using probabilistic and/xor trees or Markov networks. We further propose that the parameters of the ranking function be learned from user preferences, and we develop an approach to learn those parameters. Finally, we present a comprehensive experimental study that illustrates the effectiveness of our parameterized ranking functions, especially PRFe, at approximating other ranking functions and the scalability of our proposed algorithms for exact or approximate ranking.

Using formal specifications to support testing - Hierons,Robert M.; Krause,Paul; Lüttgen,Gerald; Simons,Anthony J. H.; Vilkomir,Sergiy; Woodward,Martin R.; Zedan,Hussein; Bogdanov,Kirill; Bowen,Jonathan P.; Cleaveland, Rance; Derrick,John; Dick,Jeremy; et al. (ACM Computing Surveys, 2009)

ACamera Phone Based Currency Reader for the Visually Impaired - Liu,Xu; David Doermann (The Tenth International ACMSIG ACCESS Conference on Computers and Accessibility, 2008)
In this paper we present a camera phone-based currency reader for the visually impaired to denominate face values of the U.S. paper dollars. Currently, they can only be identified visually and this situation will continue in foreseeable future. Our solution harvests the imaging and computational power on camera phones to read bills. Considering it is impractical for the visually impaired to capture high quality image, our currency reader performs real time processing for each captured frame as the camera approaches the bill. We develop efficient background subtraction and perspective correction algorithms and train our currency reader using the Ada-boost framework, which is efficient. Our currency reader processes 10 frames/second and achieves a false positive rate of 10^-4. Major smart phone platforms, including Symbian and Windows Mobile, are supported.

ACamera-based Mobile Data Channel: Capacity and Analysis - Liu,Xu; David Doermann; Li,H. (ACM International Conference on Multimedia, 2008)
In this paper we propose a novel application, color Video Code (V-Code) and analyze its data transmission capacity through camera-based mobile data channels. Users can use the camera on a mobile device (PDA or camera phone) as a passive and pervasive data channel to download data encoded as a sequence of color visual patterns. The color V-Code is animated on a display, acquired by the camera and decoded by the pre-embedded software in the mobile device. One interesting question is what is the data transmission capacity it can achieve, theoretically and practically. To answer this question we build a camera channel model to measure color degradation using information theory and show that the capacity of the camera channel can be improved with the optimized color selection through color calibration. After initialization color models are learned automatically as downloading proceeds. We address the problem of precise registration, and implemented a fast perspective correction method to accelerate the decoder in real-time on a resource constrained device. With the optimized color set and efficient implementation we achieve a transmission bit rate of 15.4kbps on a common iMate Jamin phone (200MHz CPU). This speed is faster than the average GPRS bit rate (12kbps).

The acl anthology reference corpus: A reference dataset for bibliographic research in computational linguistics - Bird,S.; Dale,R.; Dorr, Bonnie J; Gibson,B.; Joseph,M.T.; Kan,M.Y.; Lee,D.; Powley,B.; Radev,D.R.; Tan,Y.F. (Proc. of the 6th International Conference on Language Resources and Evaluation Conference (LREC’08), 2008)
The ACL Anthology is a digital archive of conference and journal papers in natural language processing and computational linguistics.Its primary purpose is to serve as a reference repository of research results, but we believe that it can also be an object of study and a platform for research in its own right. We describe an enriched and standardized reference corpus derived from the ACL Anthology that can be used for research in scholarly document processing. This corpus, which we call the ACL Anthology Reference Corpus (ACL ARC), brings together the recent activities of a number of research groups around the world. Our goal is to make the corpus widely available, and to encourage other researchers to use it as a standard testbed for experiments in both bibliographic and bibliometric research.

Activity sensing in the wild: a field trial of ubifit garden - Consolvo,S.; McDonald,D.W.; Toscos,T.; Chen,M.Y.; Jon Froehlich; Harrison,B.; Klasnja,P.; LaMarca,A.; LeGrand,L.; Libby,R.; others (Proceeding of the twenty-sixth annual SIGCHI conference on Human factors in computing systems, 2008)

Aggregate message authentication codes - Katz, Jonathan; Lindell,A. (Topics in Cryptology–CT-RSA 2008, 2008)
We propose and investigate the notion of aggregate message authentication codes (MACs) which have the property that multiple MAC tags, computed by (possibly) different senders on multiple (possibly different) messages, can be aggregated into a shorter tag that can still be verified by a recipient who shares a distinct key with each sender. We suggest aggregate MACs as an appropriate tool for authenticated communication in mobile ad-hoc networks or other settings where resource-constrained devices share distinct keys with a single entity (such as a base station), and communication is an expensive resource.

Algorithm 879: EIGENTEST—a test matrix generator for large-scale eigenproblems - Lee,Che-Rung; Stewart, G.W. (ACM Trans. Math. Softw., 2008)
Eigentest is a package that produces real test matrices with known eigensystems. A test matrix, called an eigenmat, is generated in a factored form, in which the user can specify the eigenvalues and has some control over the condition of the eigenvalues and eigenvectors. An eigenmat A of order n requires only O(n) storage for its representation. Auxiliary programs permit the computation of (A − sI)b, (A − sI)Tb, (A − sI)−1 b, and (A − sI)−T b in O(n) operations. A special routine computes specified eigenvectors of an eigenmat and the condition of its eigenvalue. Thus eigenmats are suitable for testing algorithms based on Krylov sequences, as well as others based on matrix-vector products. This article introduces the eigenmat and describes implementations in Fortran 77, Fortran 95, C, and Matlab.
Keywords: Eigensystem; test matrix generation

Augmenting spatio-textual search with an infectious disease ontology - Lieberman,M.D.; Sankaranarayanan,J.; Samet, Hanan; Sperling,J. (Data Engineering Workshop, 2008. ICDEW 2008. IEEE 24th International Conference on, 2008)
A system is described that automatically categorizes and classifies infectious disease incidence reports by type and geographic location, to aid analysis by domain experts. It identifies references to infectious diseases by using a disease ontology. The system leverages the textual and spatial search capabilities of the STEWARD system to enable queries such as reports on "influenza" near "Hong Kong", possibly within a particular time period. Documents from the U.S. National Library of Medicine (http://www.pubmed.gov) and the World Health Organization (http://www.who.int) are tagged so that spatial relationships to specific disease occurrences can be presented graphically via a map interface. In addition, newspaper articles can be tagged and indexed to bolster the surveillance of ongoing epidemics. Examining past epidemics using this system may lead to improved understanding of the cause and spread of infectious diseases.
Keywords: (artificial; article; ontology; spatio-textual; disease; map; engines; information; intelligence); search; interface; newspaper; search; classification; diseases; indexing; medical; STEWARD; system; classification; epidemics; indexing; infectious; systems; ontologies

A Bayesian statistics approach to multiscale coarse graining - Liu,P.; Shi,Q.; Daumé, Hal; Voth,G. A (The Journal of chemical physics, 2008)

Bittorrent is an auction: analyzing and improving bittorrent's incentives - Levin,Dave; LaCurts,Katrina; Spring, Neil; Bhattacharjee, Bobby (Proceedings of the ACM SIGCOMM 2008 conference on Data communication, 2008)
Incentives play a crucial role in BitTorrent, motivating users to upload to others to achieve fast download times for all peers. Though long believed to be robust to strategic manipulation, recent work has empirically shown that BitTorrent does not provide its users incentive to follow the protocol. We propose an auction-based model to study and improve upon BitTorrent's incentives. The insight behind our model is that BitTorrent uses, not tit-for-tat as widely believed, but an auction to decide which peers to serve. Our model not only captures known, performance-improving strategies, it shapes our thinking toward new, effective strategies. For example, our analysis demonstrates, counter-intuitively, that BitTorrent peers have incentive to intelligently under-report what pieces of the file they have to their neighbors. We implement and evaluate a modification to BitTorrent in which peers reward one another with proportional shares of bandwidth. Within our game-theoretic model, we prove that a proportional-share client is strategy-proof. With experiments on PlanetLab, a local cluster, and live downloads, we show that a proportional-share unchoker yields faster downloads against BitTorrent and BitTyrant clients, and that under-reporting pieces yields prolonged neighbor interest.
Keywords: auctions; bittorrent; incentive systems; proportional share; tit-for-tat

Camera Phone Based Tools for People with Visual Impairments - Liu,Xu; David Doermann; Li,H. (The First International Workshop on Mobile Multimedia Processing, 2008)
In this paper we describe a set of applications that utilize a camera phone to help the visually impaired with daily tasks. Our “MobileEye” software suite turns a camera enabled mobile device into a multi-purpose vision tool that helps individuals with visual disabilities. MobileEye consists of four subsystems for different types of visual disabilities. A color channel mapper helps distinguish colors, a software magnifier helps low vision individuals see detail, a pattern recognizer helps the severely impaired recognize objects and a document retriever provides access to printed materials. We apply cutting edge computer vision and image processing technologies on the mobile devices and tackle the challenges of limited computational resources and low image quality. We also consider the usability for the visually impaired so our system requires minimum keyboard operation. We provide a full software solution which runs on Symbian and Windows Mobile handsets. This paper provides a high level overview of the system.

Canny edge detection on NVIDIA CUDA - Luo,Yuancheng; Duraiswami, Ramani (Computer Vision and Pattern Recognition Workshops, 2008. CVPRW '08. IEEE Computer Society Conference on, 2008)
The Canny edge detector is a very popular and effective edge feature detector that is used as a pre-processing step in many computer vision algorithms. It is a multi-step detector which performs smoothing and filtering, non-maxima suppression, followed by a connected-component analysis stage to detect ldquotruerdquo edges, while suppressing ldquofalserdquo non edge filter responses. While there have been previous (partial) implementations of the Canny and other edge detectors on GPUs, they have been focussed on the old style GPGPU computing with programming using graphical application layers. Using the more programmer friendly CUDA framework, we are able to implement the entire Canny algorithm. Details are presented along with a comparison with CPU implementations. We also integrate our detector in to MATLAB, a popular interactive simulation package often used by researchers. The source code will be made available as open source.
Keywords: algorithms; connected-component; analysis; application; Canny; CUDA; computer; detection; feature; detection; NVIDIA; detector; filtering; graphical; detector; non; edge; extraction; smoothing; feature; filter; layers; multistep; methods; responses; nonmaxima; stage; edge; suppression; smoothing; computer; VISION; vision; edge

Capacity of Asynchronous Random-Access Scheduling in Wireless Networks - Chafekar,D.; Levin,D.; Kumar,V. S.A; Marathe,M. V; Parthasarathy,S.; Srinivasan, Aravind (IEEE INFOCOM 2008. The 27th Conference on Computer Communications, 2008)
We study the throughput capacity of wireless networks which employ (asynchronous) random-access scheduling as opposed to deterministic scheduling. The central question we answer is: how should we set the channel-access probability for each link in the network so that the network operates close to its optimal throughput capacity? We design simple and distributed channel-access strategies for random-access networks which are provably competitive with respect to the optimal scheduling strategy, which is deterministic, centralized, and computationally infeasible. We show that the competitiveness of our strategies are nearly the best achievable via random-access scheduling, thus establishing fundamental limits on the performance of random- access. A notable outcome of our work is that random access compares well with deterministic scheduling when link transmission durations differ by small factors, and much worse otherwise. The distinguishing aspects of our work include modeling and rigorous analysis of asynchronous communication, asymmetry in link transmission durations, and hidden terminals under arbitrary link-conflict based wireless interference models.
Keywords: asynchronous random-access scheduling; channel access probability; Computer networks; Computer science; Educational institutions; Interference; Optimal scheduling; Peer to peer computing; probability; Processor scheduling; radio link; radio links; radio networks; Routing; scheduling; Throughput; throughput capacity; wireless channels; Wireless networks

The Complete Genome Sequence of Thermococcus Onnurineus NA1 Reveals a Mixed Heterotrophic and Carboxydotrophic Metabolism - Lee,Hyun Sook; Kang,Sung Gyun; Bae,Seung Seob; Lim,Jae Kyu; Cho,Yona; Kim,Yun Jae; Jeon,Jeong Ho; Cha,Sun-Shin; Kwon,Kae Kyoung; Kim,Hyung-Tae; Park,Cheol-Joo; Lee,Hee-Wook; et al. (Journal of BacteriologyJ. Bacteriol., 2008)
Members of the genus Thermococcus, sulfur-reducing hyperthermophilic archaea, are ubiquitously present in various deep-sea hydrothermal vent systems and are considered to play a significant role in the microbial consortia. We present the complete genome sequence and feature analysis of Thermococcus onnurineus NA1 isolated from a deep-sea hydrothermal vent area, which reveal clues to its physiology. Based on results of genomic analysis, T. onnurineus NA1 possesses the metabolic pathways for organotrophic growth on peptides, amino acids, or sugars. More interesting was the discovery that the genome encoded unique proteins that are involved in carboxydotrophy to generate energy by oxidation of CO to CO2, thereby providing a mechanistic basis for growth with CO as a substrate. This lithotrophic feature in combination with carbon fixation via RuBisCO (ribulose 1,5-bisphosphate carboxylase/oxygenase) introduces a new strategy with a complementing energy supply for T. onnurineus NA1 potentially allowing it to cope with nutrient stress in the surrounding of hydrothermal vents, providing the first genomic evidence for the carboxydotrophy in Thermococcus.

Computer Vision and Image Processing Techniques for Mobile Application - Liu,Xu; David Doermann (Center for Automation Research, University of Maryland, 2008)
Camera phones have penetrated every corner of society and have become a focal point for communications. In our research we extend the traditional use of such devices to help bridge the gap between physical and digital worlds. Their combined image acquisition, processing, storage, and communication capabilities in a compact, portable device make them an ideal platform for embedding computer vision and image processing capabilities in the pursuit of new mobile applications. This technical report is presented as a series of computer vision and image processing techniques together with their applications on the mobile device. We have developed a set of techniques for ego-motion estimation, enhancement, feature extraction, perspective correction, object detection, and document retrieval that serve as a basis for such applications. Our applications include a dynamic video barcode that can transfer significant amounts of information visually, a document retrieval system that can retrieve documents from low resolution snapshots, and a series of applications for the users with visual disabilities such as a currency reader. Solutions for mobile devices require a fundamentally different approach than traditional vision techniques that run on traditional computers, so we consider user-device interaction and the fact that these algorithms must execute in a resource constrained environment. For each problem we perform both theoretical and empirical analysis in an attempt to optimize performance and usability. The thesis makes contributions related to efficient implementation of image processing and computer vision techniques, analysis of information theory, feature extraction and analysis of low quality images, and device usability.

Contribution to a Taxonomy of Non-Manifold Models Based on Topological Properties - Leon,Jean-Claude; De Floriani, Leila (ASME Conference Proceedings, 2008)
Non-manifold models have classically been used in Finite Element (FE) simulations to describe the shape of a mechanical part. Sketching the shape of an object is also important in a design stage, where non-manifold models could be of help for the designer. The purpose of the taxonomy proposed here is to be able either to accept or reject them based on the design context and on the type of product. This will contribute to model non-manifold objects and to their binary classification. The proposed taxonomy is also based on the topological properties of non-manifold objects, and especially on topological invariants. We will classify several topological properties as local or global ones, and we will illustrate how such properties can help either modelling these objects or searching for them in industrial data bases when large numbers of FE models have been stored.

Data Sonification for Users with Visual Impairment: A Case Study with Georeferenced Data - Zhao,Haixia; Plaisant, Catherine; Shneiderman, Ben; Lazar,Jonathan (ACM Trans. Comput.-Hum. Interact., 2008)
We describe the development and evaluation of a tool, iSonic, to assist users with visual impairment in exploring georeferenced data using coordinated maps and tables, augmented with nontextual sounds and speech output. Our in-depth case studies with 7 blind users during 42 hours of data collection, showed that iSonic enabled them to find facts and discover trends in georeferenced data, even in unfamiliar geographical contexts, without special devices. Our design was guided by an Action-by-Design-Component (ADC) framework, which was also applied to scatterplots to demonstrate its generalizability. Video and download is available at www.cs.umd.edu/hcil/iSonic/.
Keywords: auditory user interfaces; information seeking; Interactive sonification; universal usability; users with visual impairment

Design and implementation of blackboard-based system for human detection - Zhuolin Jiang; Li,S.F.; Gao,D.F. (Jisuanji Gongcheng/ Computer Engineering, 2008)

Digital image forensics via intrinsic fingerprints - Swaminathan,A.; M. Wu; Liu,K. J.R (Information Forensics and Security, IEEE Transactions on, 2008)
Digital imaging has experienced tremendous growth in recent decades, and digital camera images have been used in a growing number of applications. With such increasing popularity and the availability of low-cost image editing software, the integrity of digital image content can no longer be taken for granted. This paper introduces a new methodology for the forensic analysis of digital camera images. The proposed method is based on the observation that many processing operations, both inside and outside acquisition devices, leave distinct intrinsic traces on digital images, and these intrinsic fingerprints can be identified and employed to verify the integrity of digital data. The intrinsic fingerprints of the various in-camera processing operations can be estimated through a detailed imaging model and its component analysis. Further processing applied to the camera captured image is modelled as a manipulation filter, for which a blind deconvolution technique is applied to obtain a linear time-invariant approximation and to estimate the intrinsic fingerprints associated with these postcamera operations. The absence of camera-imposed fingerprints from a test image indicates that the test image is not a camera output and is possibly generated by other image production processes. Any change or inconsistencies among the estimated camera-imposed fingerprints, or the presence of new types of fingerprints suggest that the image has undergone some kind of processing after the initial capture, such as tampering or steganographic embedding. Through analysis and extensive experimental studies, this paper demonstrates the effectiveness of the proposed framework for nonintrusive digital image forensics.
Keywords: ACQUISITION; analysis; intrinsic; approximation; cameras; digital; camera; deconvolution; digital; devices; blind; fingerprints; time; forensics; forensic; identification; image; image; images; digital; invariant; photography; fingerprint; sensors

The draft genome of the transgenic tropical fruit tree papaya (Carica papaya Linnaeus) - Ming,R.; Hou,S.; Feng,Y.; Yu,Q.; Dionne-Laporte,A.; Saw,J.H.; Senin,P.; Wang,W.; Ly,B.V.; Lewis,K.L.T.; others (Nature, 2008)
Papaya, a fruit crop cultivated in tropical and subtropical regions, is known for its nutritional benefits and medicinal applications. Here we report a 3 draft genome sequence of 'SunUp' papaya, the first commercial virus-resistant transgenic fruit tree to be sequenced. The papaya genome is three times the size of the Arabidopsis genome, but contains fewer genes, including significantly fewer disease-resistance gene analogues. Comparison of the five sequenced genomes suggests a minimal angiosperm gene set of 13,311. A lack of recent genome duplication, atypical of other angiosperm genomes sequenced so far, may account for the smaller papaya gene number in most functional groups. Nonetheless, striking amplifications in gene number within particular functional groups suggest roles in the evolution of tree-like habit, deposition and remobilization of starch reserves, attraction of seed dispersal agents, and adaptation to tropical daylengths. Transgenesis at three locations is closely associated with chloroplast insertions into the nuclear genome, and with topoisomerase I recognition sites. Papaya offers numerous advantages as a system for fruit-tree functional genomics, and this draft genome sequence provides the foundation for revealing the basis of Carica's distinguishing morpho-physiological, medicinal and nutritional properties.

Efficient and Resilient Backbones for Multihop Wireless Networks - Lee,Seungjoon; Bhattacharjee, Bobby; Srinivasan, Aravind; Khuller, Samir (Mobile Computing, IEEE Transactions on, 2008)
We consider the problem of finding "backbones" in multihop wireless networks. The backbone provides end-to-end connectivity, allowing nonbackbone nodes to save energy since they do not have to route nonlocal data or participate in the routing protocol. Ideally, such a backbone would be small, consist primarily of high capacity nodes, and remain connected even when nodes are mobile or fail. Unfortunately, it is often infeasible to construct a backbone that has all of these properties; e.g., a small optimal backbone is often too sparse to handle node failures or high mobility. We present a parameterized backbone construction algorithm that permits explicit trade-offs between backbone size, resilience to node movement and failure, energy consumption, and path lengths. We prove that our scheme can construct essentially best possible backbones (with respect to energy consumption and backbone size) when the network is relatively static. We generalize our scheme to build more robust structures better suited to networks with higher mobility. We present a distributed protocol based upon our algorithm and show that this protocol builds and maintains a connected backbone in dynamic networks. Finally, we present detailed packet-level simulation results to evaluate and compare our scheme with existing energy-saving techniques. Our results show that, depending on the network environment, our scheme increases network lifetimes by 20 percent to 220 percent without adversely affecting delivery ratio or end-to-end latency.
Keywords: algorithm; protocols; wireless; backbone; channels; CONSTRUCTION; distributed; networks; parameterized; protocol; multihop; wireless

Energy Efficient Monitoring in Sensor Networks - Deshpande, Amol; Khuller, Samir; Malekian,Azarakhsh; Toossi,Mohammed (LATIN 2008: Theoretical InformaticsLATIN 2008: Theoretical Informatics, 2008)
In this paper we study a set of problems related to efficient energy management for monitoring applications in wireless sensor networks. We study several generalizations of a basic problem called Set k -Cover, which can be described as follows: we are given a set of sensors, and a set of regions to be monitored. Each region can be monitored by a subset of the sensors. To increase the lifetime of the sensor network, we would like to partition the sensors into k sets (or time-slots) and activate each partition in a different time-slot. The goal is to find the partitioning that maximizes the coverage of the regions. This problem is known to be NP -hard. We first develop improved approximation algorithms for this problem based on its similarities to the max k -cut problem. We then consider a variation, called Set ( k , α )-cover, where each sensor is allowed to be active in α different time-slots. We develop a randomized routing algorithm for this problem. We then consider extensions where each sensor can monitor only a bounded number of regions in any time-slot. We develop the first approximation algorithms for this problem. An experimental evaluation of the algorithms we propose can be found in the full version of the paper.

Environmental signatures associated with cholera epidemics - Constantin de Magny,G.; Murtugudde,R.; Sapiano,M. R. P.; Nizam,A.; Brown,C. W.; Busalacchi,A. J.; Yunus,M.; Nair,G. B.; Gil,A. I.; Lanata,C. F.; Rita R Colwell (Proceedings of the National Academy of Sciences, 2008)
The causative agent of cholera, Vibrio cholerae, has been shown to be autochthonous to riverine, estuarine, and coastal waters along with its host, the copepod, a significant member of the zooplankton community. Temperature, salinity, rainfall and plankton have proven to be important factors in the ecology of V. cholerae, influencing the transmission of the disease in those regions of the world where the human population relies on untreated water as a source of drinking water. In this study, the pattern of cholera outbreaks during 1998–2006 in Kolkata, India, and Matlab, Bangladesh, and the earth observation data were analyzed with the objective of developing a prediction model for cholera. Satellite sensors were used to measure chlorophyll a concentration (CHL) and sea surface temperature (SST). In addition, rainfall data were obtained from both satellite and in situ gauge measurements. From the analyses, a statistically significant relationship between the time series for cholera in Kolkata, India, and CHL and rainfall anomalies was determined. A statistically significant one month lag was observed between CHL anomaly and number of cholera cases in Matlab, Bangladesh. From the results of the study, it is concluded that ocean and climate patterns are useful predictors of cholera epidemics, with the dynamics of endemic cholera being related to climate and/or changes in the aquatic ecosystem. When the ecology of V. cholerae is considered in predictive models, a robust early warning system for cholera in endemic regions of the world can be developed for public health planning and decision making.ecology epidemiology microbiology remote sensing

Environmental Vibrio spp., isolated in Mozambique, contain a polymorphic group of integrative conjugative elements and class 1 integrons - Taviani,Elisa; Ceccarelli,Daniela; Lazaro,Nivalda; Bani,Stefania; Cappuccinelli,Piero; Rita R Colwell; Colombo,Mauro M. (FEMS Microbiology Ecology, 2008)
Circulation of mobile genetic elements linked to drug resistance spread was studied in Vibrio strains isolated from surface urban water (river and sea) and shellfish samples in 2002–2003 in Maputo, Mozambique. Class 1 integrons and integrating conjugative elements (ICE) were investigated by PCR and mating experiments in strains of major health interest: 10 Vibrio cholerae, six Vibrio parahaemolyticus, two Vibrio alginolyticus and one Vibrio fluvialis. Resistance to at least two antibiotics (predominantly β-lactams) was detected in all the strains, with additional resistances to sulfamethoxazole, spectinomycin, streptomycin and/or trimethoprim. Class 1 integrons contributed partially to the expression of drug resistance and were found in five isolates: four V. cholerae (blaP1 cassette, one strain also contained the dfrA15 cassette) and one V. alginolyticus (aadA2 cassette). ICEs, apparently devoid of resistance genes, were found in eight V. cholerae, three V. parahaemolyticus and one V. fluvialis isolates. A wide variability was observed by molecular characterization of ICEs. Five ICEs were included in the SXT/R391 family and seven ICEs were not classified. Our results indicate that the SXT/R391 family and related ICEs comprise a large class of polymorphic genetic elements widely circulating in environmental Vibrio strains in Africa, beside those evidently linked to drug resistance in clinical isolates.
Keywords: ICE; integron; Mozambique; Vibrio

Evaluating Visual Analytics at the 2007 VAST Symposium Contest - Plaisant, Catherine; Grinstein,G.; Scholtz,J.; Whiting,M.; O'Connell,T.; Laskowski,S.; Chien,L.; Tat,A.; Wright,W.; Gorg,C.; Zhicheng Liu; Parekh,N.; et al. (Computer Graphics and Applications, IEEE, 2008)
In this article, we report on the contest's data set and tasks, the judging criteria, the winning tools, and the overall lessons learned in the competition. We believe that by organizing these contests, we're creating useful resources for researchers and are beginning to understand how to better evaluate VA tools. Competitions encourage the community to work on difficult problems, improve their tools, and develop baselines for others to build or improve upon. We continue to evolve a collection of data sets, scenarios, and evaluation methodologies that reflect the richness of the many VA tasks and applications.
Keywords: 2007; analytics; analytics; data; and; Contest; Visual; Science; Symposium; Technology; data; VAST; visualisation; visualization; visual

Exploiting ontology structure and patterns of annotation to mine significant associations between pairs of controlled vocabulary terms - Lee,W. J; Raschid, Louiqa; Sayyadi,H.; Srinivasan,P. (Data Integration in the Life Sciences, 2008)

Exurbia from the bottom-up: Confronting empirical challenges to characterizing a complex system - Brown,Daniel G.; Robinson,Derek T.; An,Li; Nassauer,Joan I.; Zellner,Moira; Rand, William; Riolo,Rick; Page,Scott E.; Low,Bobbi; Wang,Zhifang (Geoforum, 2008)
We describe empirical results from a multi-disciplinary project that support modeling complex processes of land-use and land-cover change in exurban parts of Southeastern Michigan. Based on two different conceptual models, one describing the evolution of urban form as a consequence of residential preferences and the other describing land-cover changes in an exurban township as a consequence of residential preferences, local policies, and a diversity of development types, we describe a variety of empirical data collected to support the mechanisms that we encoded in computational agent-based models. We used multiple methods, including social surveys, remote sensing, and statistical analysis of spatial data, to collect data that could be used to validate the structure of our models, calibrate their specific parameters, and evaluate their output. The data were used to investigate this system in the context of several themes from complexity science, including have (a) macro-level patterns; (b) autonomous decision making entities (i.e., agents); (c) heterogeneity among those entities; (d) social and spatial interactions that operate across multiple scales and (e) nonlinear feedback mechanisms. The results point to the importance of collecting data on agents and their interactions when producing agent-based models, the general validity of our conceptual models, and some changes that we needed to make to these models following data analysis. The calibrated models have been and are being used to evaluate landscape dynamics and the effects of various policy interventions on urban land-cover patterns.
Keywords: Ecological effects; Land-cover change; Land-use change; spatial modeling; Urban sprawl

Fast concurrent object classification and localization - Tom Yeh; Lee,John J; Darrell,Trevor (CSAIL Technical Reports (July 1, 2003 - present), 2008)
Object localization and classification are important problems incomputer vision. However, in many applications, exhaustive searchover all class labels and image locations is computationallyprohibitive. While several methods have been proposed to makeeither classification or localization more efficient, few havedealt with both tasks simultaneously. This paper proposes anefficient method for concurrent object localization andclassification based on a data-dependent multi-classbranch-and-bound formalism. Existing bag-of-featuresclassification schemes, which can be expressed as weightedcombinations of feature counts can be readily adapted to ourmethod. We present experimental results that demonstrate the meritof our algorithm in terms of classification accuracy, localizationaccuracy, and speed, compared to baseline approaches includingexhaustive search, the ISM method, and single-class branch andbound.

Fast, easy, and cheap: Construction of statistical machine translation models with MapReduce - Dyer,C.; Cordova,A.; Mont,A.; Jimmy Lin (Proceedings of the Third Workshop on Statistical Machine Translation, 2008)
In recent years, the quantity of parallel train-ing data available for statistical machine trans- lation has increased far more rapidly than the performance of individual computers, re- sulting in a potentially serious impediment to progress. Parallelization of the model- building algorithms that process this data on computer clusters is fraught with challenges such as synchronization, data exchange, and fault tolerance. However, the MapReduce programming paradigm has recently emerged as one solution to these issues: a powerful functional abstraction hides system-level de- tails from the researcher, allowing programs to be transparently distributed across potentially very large clusters of commodity hardware. We describe MapReduce implementations of two algorithms used to estimate the parame- ters for two word alignment models and one phrase-based translation model, all of which rely on maximum likelihood probability esti- mates. On a 20-machine cluster, experimental results show that our solutions exhibit good scaling characteristics compared to a hypo- thetical, optimally-parallelized version of cur- rent state-of-the-art single-core tools.

A Fast Similarity Join Algorithm Using Graphics Processing Units - Lieberman,M.D.; Sankaranarayanan,J.; Samet, Hanan (Data Engineering, 2008. ICDE 2008. IEEE 24th International Conference on, 2008)
A similarity join operation A BOWTIEepsiv B takes two sets of points A, B and a value epsiv isin Ropf, and outputs pairs of points p isin A,q isin B, such that the distance D(p, q) les epsiv. Similarity joins find use in a variety of fields, such as clustering, text mining, and multimedia databases. A novel similarity join algorithm called LSS is presented that executes on a graphics processing unit (GPU), exploiting its parallelism and high data throughput. As GPUs only allow simple data operations such as the sorting and searching of arrays, LSS uses these two operations to cast a similarity join operation as a GPU sort-and-search problem. It first creates, on the fly, a set of space-filling curves on one of its input datasets, using a parallel GPU sort routine. Next, LSS processes each point p of the other dataset in parallel. For each p, it searches an interval of one of the space-filling curves guaranteed to contain all the pairs in which p participates. Using extensive theoretical and experimental analysis, LSS is shown to offer a good balance between time and work efficiency. Experimental results demonstrate that LSS is suitable for similarity joins in large high-dimensional datasets, and that it performs well when compared against two existing prominent similarity join methods.
Keywords: algorithm; graphics; algorithms; quadtrees; set; arrays; curves; parallel; join; problem; space-filling; PROCESSING; searching; fast; similarity; theory; sorting; units; sort-and-search

On the fidelity of 802.11 packet traces - Schulman,A.; Levin,D.; Spring, Neil (Proceedings of the 9th international conference on Passive and active network measurement, 2008)

Flowers or a robot army?: encouraging awareness & activity with personal, mobile displays - Consolvo,Sunny; Klasnja,Predrag; McDonald,David W.; Avrahami,Daniel; Jon Froehlich; LeGrand,Louis; Libby,Ryan; Mosher,Keith; Landay,James A. (Proceedings of the 10th international conference on Ubiquitous computing, 2008)
Personal, mobile displays, such as those on mobile phones, are ubiquitous, yet for the most part, underutilized. We present results from a field experiment that investigated the effectiveness of these displays as a means for improving awareness of daily life (in our case, self-monitoring of physical activity). Twenty-eight participants in three experimental conditions used our UbiFit system for a period of three months in their day-to-day lives over the winter holiday season. Our results show, for example, that participants who had an awareness display were able to maintain their physical activity level (even during the holidays), while the level of physical activity for participants who did not have an awareness display dropped significantly. We discuss our results and their general implications for the use of everyday mobile devices as awareness displays.
Keywords: ambient display; awareness; calm technology; field experiment; fitness; glanceable display; mobile phone; personal mobile display; persuasive technology; physical activity

Handling expected polynomial-time strategies in simulation-based security proofs - Katz, Jonathan; Lindell,Y. (Journal of Cryptology, 2008)
The standard class of adversaries considered in cryptography is that of strict polynomial-time probabilistic machines. However, expected polynomial-time machines are often also considered. For example, there are many zero-knowledge protocols for which the only known simulation techniques run in expected (and not strict) polynomial time. In addition, it has been shown that expected polynomial-time simulation is essential for achieving constant-round black-box zero-knowledge protocols. This reliance on expected polynomial-time simulation introduces a number of conceptual and technical difficulties. In this paper, we develop techniques for dealing with expected polynomial-time adversaries in simulation-based security proofs.

Handwritten Document Image Processing - Yefeng Zheng; David Doermann; Huiping Li (VDMVerlang Dr. Muller, 2008)

Hci for community and international development - Thomas, John; Dearden, Andy; Dray, Susan; Light, Ann; Best, Michael; Arkin, Nuray; Maunder, Andrew; Kam, Mathew; Marshini Chetty; Sambasivan, Nithya; Buckhalter, Celeste; Krishnan, Gaurishankar (SIGCHI EA '08, 2008)
This workshop explores the challenges in applying, extending and inventing appropriate methods and contributions of Human Computer Interaction (HCI) to International economic and community Development. We address interaction design for parts of the world that are often marginalized by the Global North as well as people in the Global North who are themselves similarly marginalized by poverty or other barriers. We hope to extend the boundaries of the field of Human Computer Interaction by spurring a discussion on how existing methods and practices can be adapted and modified, and how new practices can be developed, to deal with the unique challenges posed by these contexts.
Keywords: community design; ict4d; information and communication technology; international development; participatory design; ucd4id; User centered design

How Do Users Find Things with PubMed? Towards Automatic Utility Evaluation with User Simulations - Jimmy Lin; Smucker,Mark D. (Human-Computer Interaction Lab, University of Maryland, College Park, 2008)
In the context of document retrieval in the biomedical domain, this paper explores the complex relationship between the quality of initial query results and the overall utility of an interactive system. We demonstrate that a content-similarity browsing tool can compensate for poor retrieval results, and that the relationship between retrieval performance and overall utility is non-linear. Arguments are advanced with user simulations, which characterize the relevance of documents that a user might encounter with different browsing strategies. With broader implications to IR, this work provides a case study of how user simulations can be exploited as a formative tool for automatic utility evaluation. Simulation-based studies provide researchers with an additional evaluation tool to complement interactive and Cranfield-style experiments.
Keywords: *BIOMEDICAL INFORMATION SYSTEMS; *BROWSING; *INFORMATION RETRIEVAL; *PUBMED; *SIMILARITY; *SIMULATION; *USER NEEDS; DOCUMENTS; FIND-SIMILAR; HUMAN FACTORS ENGINEERING & MAN MACHINE SYSTEM; INFORMATION SCIENCE; MAN COMPUTER INTERFACE; QUALITY; queries; searching; TEST AND EVALUATION; UTILITY

ilearn on the iphone: Real-time human activity classification on commodity mobile phones - Saponas,T.; Lester,J.; Jon Froehlich; Fogarty,J.; Landay,J. (University of Washington CSE Tech Report UW-CSE-08-04-02, 2008)

Immunity-Based Epidemic Routing in Intermittent Networks - Mundur, Padma; Seligman,M.; Jin Na Lee (5th Annual IEEE Communications Society Conference on Sensor, Mesh and Ad Hoc Communications and Networks, 2008. SECON '08, 2008)
In this research, we propose to modify and extend epidemic routing used in intermittent networks. In particular, we propose to include immunity-based information disseminated in the reverse once messages get delivered to their destination. The goal is to design a more efficient routing protocol in terms of resource utilization. The idea is to analyze and evaluate the network performance using an immunity scheme in the context of epidemic routing and its variants. The reverse dissemination of such information requires minimal resources and the tradeoff in timely purging of delivered messages can be significant. We are using ns2 to implement a detailed simulation of the proposed immunity-based epidemic routing.
Keywords: Analytical models; Delay; delivered messages; Disruption tolerant networking; Educational institutions; immunity-based epidemic routing; information dissemination; intermittent networks; Mobile ad hoc networks; Network topology; Performance analysis; Resource management; resource utilization; routing protocol; routing protocols; telecommunication network topology

An improved mean shift tracking method based on nonparametric clustering and adaptive bandwidth - Zhuolin Jiang; Li,Shao-Fa; Jia,Xi-Ping; Zhu,Hong-Li (Machine Learning and Cybernetics, 2008 International Conference on, 2008)
An improved mean shift method for object tracking based on nonparametric clustering and adaptive bandwidth is presented in this paper. Based on partitioning the color space of a tracked object by using a modified nonparametric clustering, an appearance model of the tracked object is built. It captures both the color information and spatial layout of the tracked object. The similarity measure between the target model and the target candidate is derived from the Bhattacharyya coefficient. The kernel bandwidth parameters are automatically selected by maximizing the lower bound of a log-likelihood function, which is derived from a kernel density estimate using the bandwidth matrix and the modified weight function. The experimental results show that the method can converge in an average of 2.6 iterations per frame.
Keywords: adaptive bandwidth; appearance model; bandwidth matrix; Bhattacharyya coefficient; color information; color space partitioning; image colour analysis; iterative procedure; kernel bandwidth parameter; kernel density estimate; log-likelihood function; mean shift tracking method; modified weight function; nonparametric clustering; Object detection; object representation; object tracking; pattern clustering; similarity measure; spatial layout; target candidate; target model; tracking

Interactive auditory data exploration: A framework and evaluation with geo-referenced data sonification - Zhao,H.; Plaisant, Catherine; Shneiderman, Ben; Lazar,J. (ACM Transactions on Computer-Human Interaction, 2008)
We describe an Action-by-Design-Component (ADC) framework to guide auditory interface designers for exploratory data analysis. The framework characterizes data interaction in the auditory mode as a set of Auditory Information Seeking Actions (AISAs). Contrasting AISAs with actions in visualizations, the framework also discusses design considerations for a set of Design Components to support AISAs. Applying the framework to geo-referenced data, we systematically explored and evaluated its design space. A data exploration tool, iSonic, was built for blind users. In depth case studies with 7 blind users, with over 42 hours of data collection, showed that iSonic enabled them to find facts and discover trends of geo-referenced data, even in unfamiliar geographical contexts, without special devices. The results also showed that blind users dramatically benefited from the rich set of task-oriented actions (AISAs) and the use of multiple highly coordinated data views provided by the ADC framework. Some widely used techniques in visualization, with appropriate adaptation, also work in the auditory mode. The application of the framework to scatterplots shows that the framework can be generalized and lead to the design of a unified auditory workspace for general exploratory data analysis. Readers can view a supplementary video demonstration of iSonic by visiting www.cs.umd.edu/hcil/iSonic/

Interactive Entity Resolution in Relational Data: A Visual Analytic Tool and Its Evaluation - Kang,Hyunmo; Getoor, Lise; Shneiderman, Ben; Bilgic,M.; Licamele,L. (IEEE Transactions on Visualization and Computer Graphics, 2008)
Databases often contain uncertain and imprecise references to real-world entities. Entity resolution, the process of reconciling multiple references to underlying real-world entities, is an important data cleaning process required before accurate visualization or analysis of the data is possible. In many cases, in addition to noisy data describing entities, there is data describing the relationships among the entities. This relational data is important during the entity resolution process; it is useful both for the algorithms which determine likely database references to be resolved and for visual analytic tools which support the entity resolution process. In this paper, we introduce a novel user interface, D-Dupe, for interactive entity resolution in relational data. D-Dupe effectively combines relational entity resolution algorithms with a novel network visualization that enables users to make use of an entity's relational context for making resolution decisions. Since resolution decisions often are interdependent, D-Dupe facilitates understanding this complex process through animations which highlight combined inferences and a history mechanism which allows users to inspect chains of resolution decisions. An empirical study with 12 users confirmed the benefits of the relational context visualization on the performance of entity resolution tasks in relational data in terms of time as well as users' confidence and satisfaction.
Keywords: algorithms; Computer Graphics; D-Dupe; data visualisation; database management systems; Databases, Factual; graphical user interface; Graphical user interfaces; human-centered computing; Image Interpretation, Computer-Assisted; Information Storage and Retrieval; Information Visualization; interactive entity resolution; relational context visualization; Relational databases; relational entity resolution algorithm; User interfaces; user-centered design; User-Computer Interface; visual analytic tool

Introduction to Modern Cryptography - Katz, Jonathan; Lindell,Yehuda (CRC Press, 2008)
Cryptography plays a key role in ensuring the privacy and integrity of data and the security of computer networks. Introduction to Modern Cryptography provides a rigorous yet accessible treatment of modern cryptography, with a focus on formal definitions, precise assumptions, and rigorous proofs. The authors introduce the core principles of modern cryptography, including the modern, computational approach to security that overcomes the limitations of perfect secrecy. An extensive treatment of private-key encryption and message authentication follows. The authors also illustrate design principles for block ciphers, such as the Data Encryption Standard (DES) and the Advanced Encryption Standard (AES), and present provably secure constructions of block ciphers from lower-level primitives. The second half of the book focuses on public-key cryptography, beginning with a self-contained introduction to the number theory needed to understand the RSA, Diffie-Hellman, El Gamal, and other cryptosystems. After exploring public-key encryption and digital signatures, the book concludes with a discussion of the random oracle model and its applications. Serving as a textbook, a reference, or for self-study, Introduction to Modern Cryptography presents the necessary tools to fully understand this fascinating subject.
Keywords: Computer networks; computer security; Computers / Operating Systems / General; Computers / Security / General; cryptography; Language Arts & Disciplines / Communication Studies; Mathematics / Combinatorics

Learning pairwise dissimilarity profiles for appearance recognition in visual surveillance - Lin,Z.; Davis, Larry S. (Advances in Visual Computing, 2008)
Training discriminative classifiers for a large number of classes is a challenging problem due to increased ambiguities between classes. In order to better handle the ambiguities and to improve the scalability of classifiers to larger number of categories, we learn pairwise dissimilarity profiles (functions of spatial location) between categories and adapt them into nearest neighbor classification. We introduce a dissimilarity distance measure and linearly or nonlinearly combine it with direct distances. We illustrate and demonstrate the approach mainly in the context of appearance-based person recognition.

Learning Visual Shape Lexicon for Document Image Content Recognition - Zhu,Guangyu; Yu,Xiaodong; Li,Yi; David Doermann (The 10th European Conference on Computer Vision (ECCV 2008), 2008)
Developing effective content recognition methods for diverse imagery continues to challenge computer vision researchers. We present a new approach for document image content categorization using a lexicon of shape features. Each lexical word corresponds to a scale and rotation invariant shape feature that is generic enough to be detected repeatably and segmentation free. We learn a concise, structurally indexed shape lexicon from training by clustering and partitioning feature types through graph cuts. We demonstrate our approach on two challenging document image content recognition problems: 1) The classification of 4,500 Web images crawled from Google Image Search into three content categories — pure image, image with text, and document image, and 2) Language identification of 8 languages (Arabic, Chinese, English, Hindi, Japanese, Korean, Russian, and Thai) on a 1,512 complex document image database composed of mixed machine printed text and handwriting. Our approach is capable to handle high intra-class variability and shows results that exceed other state-of-the-art approaches, allowing it to be used as a content recognizer in image indexing and retrieval systems.

Leveraging social context for searching social media - Smith,Marc; Barash,Vladimir; Getoor, Lise; Lauw,Hady W. (Proceedings of the 2008 ACM workshop on Search in social media, 2008)
The ability to utilize and benefit from today's explosion of social media sites depends on providing tools that allow users to productively participate. In order to participate, users must be able to find resources (both people and information) that they find valuable. Here, we argue that in order to do this effectively, we should make use of a user's "social context". A user's social context includes both their personal social context (their friends and the communities to which they belong) and their community social context (their role and identity in different communities).
Keywords: social context; social media; social search

Matchmaking and implementation issues for a P2P desktop grid - Marsh,M.; Kim,Jik-Soo; Nam,Beomseok; Jaehwan Lee; Ratanasanya,S.; Bhattacharjee, Bobby; Keleher,P.; Richardson,D.; Wellnitz,D. (Parallel and Distributed Processing, 2008. IPDPS 2008. IEEE International Symposium on, 2008)
We present some recent and ongoing work in our decentralized desktop computing grid project. Specifically, we discuss matching jobs with compute nodes in a peer-to-peer grid of heterogeneous platforms, and the implementation of our algorithms in a concrete system.
Keywords: computing; computing; computing; peer-to-peer; desktop; grid; decentralized; grid; grid; grid; peer-to-peer; P2P

Maternal depletion of CTCF reveals multiple functions during oocyte and preimplantation embryo development - Wan,Le-Ben; Pan,Hua; Hannenhalli, Sridhar; Cheng,Yong; Ma,Jun; Fedoriw,Andrew; Lobanenkov,Victor; Latham,Keith E.; Schultz,Richard M.; Bartolomei,Marisa S. (Development, 2008)
CTCF is a multifunctional nuclear factor involved in epigenetic regulation. Despite recent advances that include the systematic discovery of CTCF-binding sites throughout the mammalian genome, the in vivo roles of CTCF in adult tissues and during embryonic development are largely unknown. Using transgenic RNAi, we depleted maternal stores of CTCF from growing mouse oocytes, and identified hundreds of misregulated genes. Moreover, our analysis suggests that CTCF predominantly activates or derepresses transcription in oocytes. CTCF depletion causes meiotic defects in the egg, and mitotic defects in the embryo that are accompanied by defects in zygotic gene expression, and culminate in apoptosis. Maternal pronuclear transfer and CTCF mRNA microinjection experiments indicate that CTCF is a mammalian maternal effect gene, and that persistent transcriptional defects rather than persistent chromosomal defects perturb early embryonic development. This is the first study detailing a global and essential role for CTCF in mouse oocytes and preimplantation embryos.

Measurement Manipulation and Space Selection in Network Coordinates - Lumezanu,Cristian; Spring, Neil (Distributed Computing Systems, International Conference on, 2008)
Internet coordinate systems have emerged as an efficient method to estimate the latency between pairs of nodes without any communication between them. However, most coordinate systems have been evaluated solely on data sets built by their authors from measurements gathered over large periods of time. Although they show good prediction results, it is unclear whether the accuracy is the result of the system design properties or is more connected to the characteristics of the data sets. In this paper, we revisit a simple question: how do the features of the embedding space and the inherent attributes of the data sets interact in producing good embeddings? We adapt the Vivaldi algorithm to use Hyperbolic space for embedding and evaluate both Euclidean and Hyperbolic Vivaldi on seven sets of real-world latencies. Our results show that node filtering and latency distributions can significantly influence the accuracy of the predictions. For example, although Euclidean Vivaldi performs well on data sets that were chosen, constructed and filtered by the designers of the algorithm, its performance and robustness decrease considerably when run on third party data sets that were not filtered a priori. Our results offer important insight into designing and building coordinate systems that are both robust and accurate in Internet-like environments.

Method and System for Detecting and Responding to Attacking Networks - Dagon,David; Feamster, Nick; Lee,Weake; Edmonds,Robert; Lipton,Richard; Ramachandran,Anirudh (2008)
A system and method for detecting a first network of compromised computers in a second network of computers, comprising: collecting Domain Name System (DNS) data for the second network; examining the collected data relative to DNS data from known comprised and/or uncompromised computers in the second network; and determining the existence of the first network and/or the identity of compromised computers in the second network based on the examination.

Methods to directly measure the trapping potential in optical tweezers - Balijepalli,A.; LeBrun,T. W.; Gorman,J. J.; Gupta,S.K. (2008)
Techniques to measure the trapping force in an optical tweezers without any prior assumptions about the trapshape have been developed. The response of a trapped micro or nanoparticle to a step input is measured and then used to calculate the trapping force experienced by the particle as a function of it’s position in the trap. This method will provide new insight into the trapping behavior of nanoparticles, which are more weakly bound than microparticles and thereby explore larger regions of the trapping potential due to Brownian motion. Langevin dynamics simulations are presented to model the system and are used to demonstrate this technique. Preliminary experimental results are then presented to validate the simulations. Finally, the measured trapping forces, from simulations and laboratory experiments, are integrated to recover the trapping potential.

Mobile Retriever: Access to Digital Documents from their Physical Source - Liu,Xu; David Doermann (International Journal on Document Analysis and Recognition, 2008)
In this paper, we describe an image based document retrieval system which runs on camera enabled mobile devices. “Mobile Retriever” aims to seamlessly link physical and digital documents by allowing users to snap a picture of the text of a document and retrieve its electronic version from a database. Experiments show that for a database of 100,093 pages, the correct document can be retrieved in less than 4 s at a success rate over 95%. Our system extracts token pairs from the text, to efficiently index and retrieve candidate pages using only a small portion of the image. We use token triplets that define the orientation of three corresponding tokens to effectively prune the false positives and identify the correct page to retrieve. We stress the importance of geometrical relationship between feature points and show its effectiveness in our camera based image retrieval system.

Modeling Transfer Relationships Between Learning Tasks for Improved Inductive Transfer - Eaton,Eric; desJardins, Marie; Lane,Terran (Machine Learning and Knowledge Discovery in DatabasesMachine Learning and Knowledge Discovery in Databases, 2008)
In this paper, we propose a novel graph-based method for knowledge transfer. We model the transfer relationships between source tasks by embedding the set of learned source models in a graph using transferability as the metric. Transfer to a new problem proceeds by mapping the problem into the graph, then learning a function on this graph that automatically determines the parameters to transfer to the new learning task. This method is analogous to inductive transfer along a manifold that captures the transfer relationships between the tasks. We demonstrate improved transfer performance using this method against existing approaches in several real-world domains.

A molecular footprint of limb loss: sequence variation of the autopodial identity gene Hoxa-13 - Kohlsdorf,T; Cummings, Michael P.; Lynch,VJ; Stopper,GF; Takahashi,K; Wagner,GP (J Mol Evol, 2008)
The homeobox gene Hoxa-13 codes for a transcription factor involved in multiple functions, including body axis and hand/foot development in tetrapods. In this study we investigate whether the loss of one function (e.g., limb loss in snakes) left a molecular footprint in exon 1 of Hoxa-13 that could be associated with the release of functional constraints caused by limb loss. Fragments of the Hoxa-13 exon 1 were sequenced from 13 species and analyzed, with additional published sequences of the same region, using relative rates and likelihood-ratio tests. Five amino acid sites in exon 1 of Hoxa-13 were detected as evolving under positive selection in the stem lineage of snakes. To further investigate whether there is an association between limb loss and sequence variation in Hoxa-13, we used the random forest method on an alignment that included shark, basal fish lineages, and "eu-tetrapods" such as mammals, turtle, alligator, and birds. The random forest method approaches the problem as one of classification, where we seek to predict the presence or absence of autopodium based on amino acid variation in Hoxa-13 sequences. Different alignments tested were associated with similar error rates (18.42%). The random forest method suggested that phenotypic states (autopodium present and absent) can often be correctly predicted based on Hoxa-13 sequences. Basal, nontetrapod gnat-hostomes that never had an autopodium were consistently classified as limbless together with the snakes, while eu-tetrapods without any history of limb loss in their phylogeny were also consistently classified as having a limb. Misclassifications affected mostly lizards, which, as a group, have a history of limb loss and limb re-evolution, and the urodele and caecilian in our sample. We conclude that a molecular footprint can be detected in Hoxa-13 that is associated with the lack of an autopodium; groups with classification ambiguity (lizards) are characterized by a history of repeated limb loss and possible limb re-evolution.

Motivating participation in internet routing overlays - Levin,Dave; Baden,Randolph; Lumezanu,Cristian; Spring, Neil; Bhattacharjee, Bobby (Proceedings of the 3rd international workshop on Economics of networked systems, 2008)
PeerWise is an Internet routing overlay that reduces end-to-end latencies by allowing peers to forward through a relay instead of connecting directly to their destinations. Fundamental to PeerWise is the notion of peering agreements between two peers, wherein they agree to forward for one another. In this paper, we consider the problem of motivating users to establish and maintain peerings in a completely decentralized, scalable manner. We show that routing overlays present unique challenges and goals. For instance, since participants can always "fall back" on standard Internet routing, we must encourage users to stay in the system and maintain long-lived peering agreements. To address these challenges, we propose two mechanisms: First, we use Service Level Agreements (SLAs) to expressively negotiate peers' demands and the recourses they will take when SLAs are violated. Second, we propose a mechanism to address SLA violations that differs from the standard notion of punishment via service degradation. Our simulation results demonstrate that our mechanism causes peers to avoid SLA violators in favor of long-lived peerings. Lastly, we discuss potential, emergent behaviors in a selfish routing overlay.
Keywords: incentives; internet routing overlays; service-level agreements

Mpeg recompression detection based on block artifacts - Luo,W.; Wu,M.; Huang,J. (Proc. of SPIE Electronic Imaging, Security, Steganography, and Watermarking of Multimedia Contents, 2008)
With sophisticated video editing technologies, it is becoming increasingly easy to tamper digital video withoutleaving visual clues. One of the common tampering operations on video is to remove some frames and then re-encode the resulting video. In this paper, we propose a new method for detecting this type of tampering by exploring the temporal patterns of the block artifacts in video sequences. We show that MPEG compression introduces different block artifacts into various types of frames and that the strength of the block artifacts as a function over time has a regular pattern for a given group of pictures (GOP) structure. When some frames are removed from an MPEG video file and the file is then recompressed, the block artifacts introduced by the previous compression would remain and affect the average of block artifact strength of the recompressed one in such a way that depends on the number of deleted frames and the type of GOP used previously. We propose a feature curve to reveal the compression history of an MPEG video file with a given GOP structure, and use it as evidence to detect tampering. Experimental results evaluated on common video benchmark clips demonstrate the effectiveness of the proposed method.

Multiple alternative sentence compressions and word-pair antonymy for automatic text summarization and recognizing textual entailment - Mohammad,S.; Dorr, Bonnie J; Egan,M.; Jimmy Lin; Zajic, David (Proceedings of the Text Analysis Conference (TAC-2008), Gaithersburg, MD, 2008)
The University of Maryland participatedin three tasks organized by the Text Anal- ysis Conference 2008 (TAC 2008): (1) the update task of text summarization; (2) the opinion task of text summariza- tion; and (3) recognizing textual entail- ment (RTE). At the heart of our summa- rization system is Trimmer, which gener- ates multiple alternative compressed ver- sions of the source sentences that act as candidate sentences for inclusion in the summary. For the first time, we investi- gated the use of automatically generated antonym pairs for both text summariza- tion and recognizing textual entailment. We used an antonymy feature in both the opinion summarization task and for rec- ognizing textual entailment. More coher- ent summaries resulted when using the antonymy feature as compared to when not using it. However, performance on ROUGE dropped. The RTE system per- formed almost equally well when using antonyms from WordNet and when using automatically generated antonyms.

Navigating information spaces: A case study of related article search in PubMed - Jimmy Lin; DiCuccio,Michael; Grigoryan,Vahan; Wilbur,W. John (Information Processing & Management, 2008)
The concept of an â€œinformation spaceâ€ provides a powerful metaphor for guiding the design of interactive retrieval systems. We present a case study of related article search, a browsing tool designed to help users navigate the information space defined by results of the PubMedÂ® search engine. This feature leverages content-similarity links that tie MEDLINEÂ® citations together in a vast document network. We examine the effectiveness of related article search from two perspectives: a topological analysis of networks generated from information needs represented in the TREC 2005 genomics track and a query log analysis of real PubMed users. Together, data suggest that related article search is a useful feature and that browsing related articles has become an integral part of how users interact with PubMed.
Keywords: Browsing; Interactive IR; MEDLINE; TREC genomics

NewsStand: a new view on news - Teitler,Benjamin E.; Lieberman,Michael D.; Panozzo,Daniele; Sankaranarayanan,Jagan; Samet, Hanan; Sperling,Jon (Proceedings of the 16th ACM SIGSPATIAL international conference on Advances in geographic information systems, 2008)
News articles contain a wealth of implicit geographic content that if exposed to readers improves understanding of today's news. However, most articles are not explicitly geotagged with their geographic content, and few news aggregation systems expose this content to users. A new system named NewsStand is presented that collects, analyzes, and displays news stories in a map interface, thus leveraging on their implicit geographic content. NewsStand monitors RSS feeds from thousands of online news sources and retrieves articles within minutes of publication. It then extracts geographic content from articles using a custom-built geotagger, and groups articles into story clusters using a fast online clustering algorithm. By panning and zooming in NewsStand's map interface, users can retrieve stories based on both topical significance and geographic region, and see substantially different stories depending on position and zoom level.
Keywords: clustering; geotagging; knowledge discovery; text mining

Optimal Cryptographic Hardness of Learning Monotone Functions - Dana Dachman-Soled; Lee, Homin K.; Malkin, Tal; Servedio, Rocco A.; Wan, Andrew; Wee, Hoeteck (Automata, Languages and Programming, 2008)
A wide range of positive and negative results have been established for learning different classes of Boolean functions from uniformly distributed random examples. However, polynomial-time algorithms have thus far been obtained almost exclusively for various classes of monotone functions, while the computational hardness results obtained to date have all been for various classes of general (nonmonotone) functions. Motivated by this disparity between known positive results (for monotone functions) and negative results (for nonmonotone functions), we establish strong computational limitations on the efficient learnability of various classes of monotone functions. We give several such hardness results which are provably almost optimal since they nearly match known positive results. Some of our results show cryptographic hardness of learning polynomial-size monotone circuits to accuracy only slightly greater than 1/2+1/n‾‾√1/2 + 1/\sqrt{n} ; this accuracy bound is close to optimal by known positive results (Blum et al., FOCS ’98). Other results show that under a plausible cryptographic hardness assumption, a class of constant-depth, sub-polynomial-size circuits computing monotone functions is hard to learn; this result is close to optimal in terms of the circuit size parameter by known positive results as well (Servedio, Information and Computation ’04). Our main tool is a complexity-theoretic approach to hardness amplification via noise sensitivity of monotone functions that was pioneered by O’Donnell (JCSS ’04).
Keywords: Data structures; Data Structures, Cryptology and Information Theory; Discrete Mathematics in Computer Science; Numeric Computing; Software Engineering/Programming and Operating Systems; Theory of computation

A pattern classification framework for theoretical analysis of component forensics - Swaminathan,A.; M. Wu; Liu,K. J.R (Acoustics, Speech and Signal Processing, 2008. ICASSP 2008. IEEE International Conference on, 2008)
Component forensics is an emerging methodology for forensic analysis that aims at estimating the algorithms and parameters in each component of a digital device. This paper proposes a theoretical foundation to examine the performance limits of component forensics. Using ideas from pattern classification theory, we define formal notions of identifiability of components in the information processing chain. We show that the parameters of certain device components can be accurately identified only in controlled settings through semi non-intrusive forensics, while the parameters of some others can be computed directly from the available sample data via complete non-intrusive analysis. We then extend the proposed theoretical framework to quantify and improve the accuracies and confidence in component parameter identification for several forensic applications.
Keywords: analysis; information; classification; classification; parameter; component; estimation; pattern; forensics; component; forensics; pattern; identification; forensic; parameter; processing; nonintrusive

Photo-based question answering - Tom Yeh; Lee,John J; Darrell,Trevor (Proceedings of the 16th ACM international conference on Multimedia, 2008)
Photo-based question answering is a useful way of finding information about physical objects. Current question answering (QA) systems are text-based and can be difficult to use when a question involves an object with distinct visual features. A photo-based QA system allows direct use of a photo to refer to the object. We develop a three-layer system architecture for photo-based QA that brings together recent technical achievements in question answering and image matching. The first, template-based QA layer matches a query photo to online images and extracts structured data from multimedia databases to answer questions about the photo. To simplify image matching, it exploits the question text to filter images based on categories and keywords. The second, information retrieval QA layer searches an internal repository of resolved photo-based questions to retrieve relevant answers. The third, human-computation QA layer leverages community experts to handle the most difficult cases. A series of experiments performed on a pilot dataset of 30,000 images of books, movie DVD covers, grocery items, and landmarks demonstrate the technical feasibility of this architecture. We present three prototypes to show how photo-based QA can be built into an online album, a text-based QA, and a mobile application.
Keywords: Computer vision; Information retrieval; Question answering

Pooled ANOVA - Last,Michael; Luta,Gheorghe; Orso,Alex; Porter, Adam; Young,Stan (Computational Statistics & Data Analysis, 2008)
We introduce Pooled ANOVA, a greedy algorithm to sequentially select the rare important factors from a large set of factors. Problems such as computer simulations and software performance tuning involve a large number of factors, few of which have an important effect on the outcome or performance measure. We pool multiple factors together, and test the pool for significance. If the pool has a significant effect we retain the factors for deconfounding. If not, we either declare that none of the factors are important, or retain them for follow-up decoding, depending on our assumptions and stage of testing. The sparser important factors are, the bigger the savings. Pooled ANOVA requires fewer assumptions than other, similar methods (e.g. sequential bifurcation), such as not requiring all important effects to have the same sign. We demonstrate savings of 25%-35% when compared to a conventional ANOVA, and also the ability to work in a setting where Sequential Bifurcation fails.

A pose-invariant descriptor for human detection and segmentation - Lin,Z.; Davis, Larry S. (Computer Vision–ECCV 2008, 2008)
We present a learning-based, sliding window-style approach for the problem of detecting humans in still images. Instead of traditional concatenation-style image location-based feature encoding, a global descriptor more invariant to pose variation is introduced. Specifically, we propose a principled approach to learning and classifying human/non-human image patterns by simultaneously segmenting human shapes and poses, and extracting articulation-insensitive features. The shapes and poses are segmented by an efficient, probabilistic hierarchical part-template matching algorithm, and the features are collected in the context of poses by tracing around the estimated shape boundaries. Histograms of oriented gradients are used as a source of low-level features from which our pose-invariant descriptors are computed, and kernel SVMs are adopted as the test classifiers. We evaluate our detection and segmentation approach on two public pedestrian datasets.

Rule-based static analysis of network protocol implementations - Udrea,O.; Lumezanu,C.; Foster, Jeffrey S. (Information and Computation, 2008)

Scalable classifiers for Internet vision tasks - Tom Yeh; Lee,John J; Darrell,Trevor (Computer Vision and Pattern Recognition Workshops, 2008. CVPRW'08. IEEE Computer Society Conference on, 2008)
Object recognition systems designed for Internet applications typically need to adapt to userspsila needs in a flexible fashion and scale up to very large data sets. In this paper, we analyze the complexity of several multiclass SVM-based algorithms and highlight the computational bottleneck they suffer at test time: comparing the input image to every training image. We propose an algorithm that overcomes this bottleneck; it offers not only the efficiency of a simple nearest-neighbor classifier, by voting on class labels based on the k nearest neighbors quickly determined by a vocabulary tree, but also the recognition accuracy comparable to that of a complex SVM classifier, by incorporating SVM parameters into the voting scores incrementally accumulated from individual image features. Empirical results demonstrate that adjusting votes by relevant support vector weights can improve the recognition accuracy of a nearest-neighbor classifier without sacrificing speed. Compared to existing methods, our algorithm achieves a ten-fold speed increase while incurring an acceptable accuracy loss that can be easily offset by showing about two more labels in the result. The speed, scalability, and adaptability of our algorithm makes it suitable for Internet vision applications.

A scalable key management and clustering scheme for wireless ad hoc and sensor networks - Li,Jason H.; Bhattacharjee, Bobby; Yu,Miao; Levy,Renato (Future Generation Computer Systems, 2008)
This paper describes a scalable key management and clustering scheme for secure group communications in ad hoc and sensor networks. The scalability problem is solved by partitioning the communicating devices into subgroups, with a leader in each subgroup, and further organizing the subgroups into hierarchies. Each level of the hierarchy is called a tier or layer. Key generation, distribution, and actual data transmissions follow the hierarchy. The distributed, efficient clustering approach (DECA) provides robust clustering to form subgroups, and analytical and simulation results demonstrate that DECA is energy-efficient and resilient against node mobility. Comparing with most other schemes, our approach is extremely scalable and efficient, provides more security guarantees, and is selective, adaptive and robust.
Keywords: ad hoc networks; clustering; Group communications; Key management; sensor networks

Scalable language processing algorithms for the masses: a case study in computing word co-occurrence matrices with MapReduce - Jimmy Lin (Proceedings of the Conference on Empirical Methods in Natural Language Processing, 2008)
This paper explores the challenge of scaling up language processing algorithms to increasingly large datasets. While cluster computing has been available in commercial environments for several years, academic researchers have fallen behind in their ability to work on large datasets. I discuss two barriers contributing to this problem: lack of a suitable programming model for managing concurrency and difficulty in obtaining access to hardware. Hadoop, an open-source implementation of Google's MapReduce framework, provides a compelling solution to both issues. Its simple programming model hides system-level details from the developer, and its ability to run on commodity hardware puts cluster computing within the reach of many academic research groups. This paper illustrates these points with a case study in building word cooccurrence matrices from large corpora. I conclude with an analysis of an alternative computing model based on renting instead of buying computer clusters.

Searching Electronic Health Records for Temporal Patterns in Patient Histories: A Case Study with Microsoft Amalga - Plaisant, Catherine; Lam,Stanley; Shneiderman, Ben; Smith,Mark S.; Roseman,David; Marchand,Greg; Gillam,Michael; Feied,Craig; Handler,Jonathan; Rappaport,Hank (AMIA Annual Symposium ProceedingsAMIA Annu Symp Proc, 2008)
As electronic health records (EHR) become more widespread, they enable clinicians and researchers to pose complex queries that can benefit immediate patient care and deepen understanding of medical treatment and outcomes. However, current query tools make complex temporal queries difficult to pose, and physicians have to rely on computer professionals to specify the queries for them. This paper describes our efforts to develop a novel query tool implemented in a large operational system at the Washington Hospital Center (Microsoft Amalga, formerly known as Azyxxi). We describe our design of the interface to specify temporal patterns and the visual presentation of results, and report on a pilot user study looking for adverse reactions following radiology studies using contrast.

Searching the world’s herbaria: A system for visual identification of plant species - Belhumeur,P.; Chen,D.; Feiner,S.; Jacobs, David W.; Kress,W.; Ling,H.; Lopez,I.; Ramamoorthi,R.; Sheorey,S.; White,S. (Computer Vision–ECCV 2008, 2008)
We describe a working computer vision system that aids in the identification of plant species. A user photographs an isolated leaf on a blank background, and the system extracts the leaf shape and matches it to the shape of leaves of known species. In a few seconds, the system displays the top matching species, along with textual descriptions and additional images. This system is currently in use by botanists at the Smithsonian Institution National Museum of Natural History. The primary contributions of this paper are: a description of a working computer vision system and its user interface for an important new application area; the introduction of three new datasets containing thousands of single leaf images, each labeled by species and verified by botanists at the US National Herbarium; recognition results for two of the three leaf datasets; and descriptions throughout of practical lessons learned in constructing this system.

Sex and Age Dimorphism of Myocardial Gene Expression in Nonischemic Human Heart Failure - Fermin,David R.; Barac,Ana; Lee,Sangjin; Polster,Sean P.; Hannenhalli, Sridhar; Bergemann,Tracy L.; Grindle,Suzanne; Dyke,David B.; Pagani,Francis; Miller,Leslie W.; Tan,Sarah; dos Remedios,Cris; et al. (Circulation: Cardiovascular Genetics, 2008)
Background— We report the first comprehensive analysis of gene expression differences by sex and age in left ventricular samples from 102 patients with dilated cardiomyopathy.Methods and Results— Gene expression data (HG-U133A gene chip, Affymetrix) were analyzed from 30 females and 72 males from 3 separate centers. More than 1800 genes displayed sexual dimorphism in the heart (adjusted P value <0.05). A significant number of these genes were highly represented in gene ontology pathways involved in ion transport and G-protein-coupled receptor signaling. Localization of these genes revealed enrichment on both the sex chromosomes as well as chromosomes 3, 4, and 14. The second goal of this study was to determine the effect of age on gene expression. Within the female cohort, >140 genes were differentially expressed in the <55 years age group compared with the >55 years age group. These genes were highly represented in gene ontology pathways involved in DNA damage. In contrast, zero genes in the male cohort <55 years met statistical significance when compared with the >55 years age group.Conclusions— Gene expression in dilated cardiomyopathy displayed evidence of sexual dimorphism similar to other somatic tissues and age dimorphism within the female cohort.

Single-document and multi-document summarization techniques for email threads using sentence compression - Zajic, David; Dorr, Bonnie J; Jimmy Lin (Information Processing & Management, 2008)
We present two approaches to email thread summarization: collective message summarization (CMS) applies a multi-document summarization approach, while individual message summarization (IMS) treats the problem as a sequence of single-document summarization tasks. Both approaches are implemented in our general framework driven by sentence compression. Instead of a purely extractive approach, we employ linguistic and statistical methods to generate multiple compressions, and then select from those candidates to produce a final summary. We demonstrate these ideas on the Enron email collection – a very challenging corpus because of the highly technical language. Experimental results point to two findings: that CMS represents a better approach to email thread summarization, and that current sentence compression techniques do not improve summarization performance in this genre.
Keywords: Email summarization; Enron; Informal media; Sentence compression; Trimming

A topic-based Document Correlation Model - Jia,Xi-Ping; Peng,Hong; Zheng,Qi-Lun; Zhuolin Jiang; Li,Zhao (Machine Learning and Cybernetics, 2008 International Conference on, 2008)
Document correlation analysis is now a focus of study in text mining. This paper proposed a Document Correlation Model to capture the correlation between documents from topic level. The model represents the document correlation as the Optimal Matching of a bipartite graph, of which each partition is a document, each node is a topic, and each edge is the similarity between two topics. The topics of each document are retrieved by the Latent Dirichlet Allocation model and Gibbs sampling. Experiments on correlated document search show that the Document Correlation Model outperforms the Vector Space Model on two aspects: 1) it has higher average retrieval precision; 2) it needs less space to store a documentpsilas information.
Keywords: bipartite graph optimal matching; data mining; document correlation analysis; document retrieval; Gibbs sampling; Information retrieval; latent Dirichlet allocation model; text analysis; text mining; topic-based document correlation model

Toward automatic facet analysis and need negotiation: Lessons from mediated search - Jimmy Lin; Wu,Philip; Abels,Eileen (ACM Transactions on Information Systems (TOIS), 2008)
This work explores the hypothesis that interactions between a trained human search intermediary and an information seeker can inform the design of interactive IR systems. We discuss results from a controlled Wizard-of-Oz case study, set in the context of the TREC 2005 HARD track evaluation, in which a trained intermediary executed an integrated search and interaction strategy based on conceptual facet analysis and informed by need negotiation techniques common in reference interviews. Having a human “in the loop” yielded large improvements over fully automated systems as measured by standard ranked-retrieval metrics, demonstrating the value of mediated search. We present a detailed analysis of the intermediary's actions to gain a deeper understanding of what worked and why. One contribution is a taxonomy of clarification types informed both by empirical results and existing theories in library and information science. We discuss how these findings can guide the development of future systems. Overall, this work illustrates how studying human information-seeking processes can lead to better information retrieval applications.
Keywords: interactive information retrieval; Reference interview

Tracking Down Under: Following the Satin Bowerbird - Kembhavi,A.; Farrell,R.; Luo,Yuancheng; Jacobs, David W.; Duraiswami, Ramani; Davis, Larry S. (Applications of Computer Vision, 2008. WACV 2008. IEEE Workshop on, 2008)
Socio biologists collect huge volumes of video to study animal behavior (our collaborators work with 30,000 hours of video). The scale of these datasets demands the development of automated video analysis tools. Detecting and tracking animals is a critical first step in this process. However, off-the-shelf methods prove incapable of handling videos characterized by poor quality, drastic illumination changes, non-stationary scenery and foreground objects that become motionless for long stretches of time. We improve on existing approaches by taking advantage of specific aspects of this problem: by using information from the entire video we are able to find animals that become motionless for long intervals of time; we make robust decisions based on regional features; for different parts of the image, we tailor the selection of model features, choosing the features most helpful in differentiating the target animal from the background in that part of the image. We evaluate our method, achieving almost 83% tracking accuracy on a more than 200,000 frame dataset of Satin Bowerbird courtship videos.
Keywords: analysis; behavior; animal; Bowerbird; animal; computing; feature; detection; animal; extraction; tracking; video; processing; zoology; Satin; sciences; selection; behavioural; signal; tool; feature; tracking; automated; video

UMD_VDT, an Integration of Detection and Tracking Methods for Multiple Human Tracking - Tran,S.; Lin,Z.; Harwood,D.; Davis, Larry S. (Multimodal Technologies for Perception of Humans, 2008)
This paper presents a cooperative body part labeling and tracking algorithm for locating body parts in a videoimage sequence. The body part labeling procedure is used to initialize the tracking procedure and to prevent tracking from getting lost; and the tracking procedure is used to analyze frames that cannot be handled reliably by the labeling procedure. This results in an automatic and robust body part tracking system. Unlike previous work that always start tracking from the first frame which may be difficult to analyze, our tracking procedure starts with some key frames in which body parts can be located reliably. Key frames are selected based on a labeling confidence measure which evaluates the similarity between the human model and the image features. The labeled body parts are tracked in-between frames based on such cues as shape, color, and location interpolated between key frames iteratively. The proposed algorithm has been applied to analyze NASA videotapes in which crew members present challenging postures of bending, twisting, and rotating in a space station. The experimental results demonstrate the effectiveness of the proposed algorithm.

Unconstrained Language Identification Using AShape Codebook - Zhu,Guangyu; Yu,Xiaodong; Li,Yi; David Doermann (The 11th International Conference on Frontiers in Handwritting Recognition (ICFHR 2008), 2008)
We propose a novel approach to language identification in document images containing handwriting and machine printed text using image descriptors constructed from a codebook of shape features. We encode local text structures using scale and rotation invariant codewords, each representing a characteristic shape feature that is generic enough to appear repeatably. We learn a concise, structurally indexed shape codebook from training data by clustering similar features and partitioning the feature space by graph cuts. Our approach is segmentation free and easily extensible. We quantitatively evaluate our approach using a large real-world document image collection, which consists of more than 1,500 documents in 8 languages (Arabic, Chinese, English, Hindi, Japanese, Korean, Russian, and Thai) and contains a complex mixture of handwritten and machine printed content. Experimental results demonstrate the robustness and flexibility of our approach, and show exceptional language identification performance that exceeds the state of art.

A Unified Framework for Multipath Routing for Unicast and Multicast Traffic - Guven,T.; La,R.J.; Shayman,M.A.; Bhattacharjee, Bobby (Networking, IEEE/ACM Transactions on, 2008)
We study the problem of load balancing the traffic from a set of unicast and multicast sessions. The problem is formulated as an optimization problem. However, we assume that the gradient of the network cost function is not available and needs to be estimated. Multiple paths are provided between a source and a destination using application-layer overlay. We propose a novel algorithm that is based on what is known as simultaneous perturbation stochastic approximation and utilizes only noisy measurements collected and reported to the sources, using an overlay architecture. We consider three network models that reflect different sets of assumptions regarding multicast capabilities of the network. Using an analytical model we first prove the almost sure convergence of the algorithm to a corresponding optimal solution under each network model considered in this paper with decreasing step sizes. Then, we establish the weak convergence (or convergence in distribution) with a fixed step size. In addition, we investigate the benefits acquired from implementing additional multicast capabilities by studying the relative performance of our algorithm under the three network models.
Keywords: application-layer; approximation; unicast; balancing; multicast; channels; stochastic; communication; multipath; cost; function; optimization; network; overlay; load; perturbation; problem; simultaneous; processes; telecommunication; routing; network; routing; telecommunication; Stochastic; traffic; traffic; multicast; traffic; multipath

Using wearable sensors and real time inference to understand human recall of routine activities - Klasnja,Predrag; Harrison,Beverly L.; LeGrand,Louis; LaMarca,Anthony; Jon Froehlich; Hudson,Scott E. (Proceedings of the 10th international conference on Ubiquitous computing, 2008)
Keywords: empirical evaluation; ESM; experience sampling method; recall accuracy; self-reports; survey frequency; user study

VAST 2008 Challenge: Introducing mini-challenges - Grinstein,G.; Plaisant, Catherine; Laskowski,S.; O'Connell,T.; Scholtz,J.; Whiting,M. (Visual Analytics Science and Technology, 2008. VAST '08. IEEE Symposium on, 2008)
Visual analytics experts realize that one effective way to push the field forward and to develop metrics for measuring the performance of various visual analytics components is to hold an annual competition. The VAST 2008 Challenge is the third year that such a competition was held in conjunction with the IEEE Visual Analytics Science and Technology (VAST) symposium. The authors restructured the contest format used in 2006 and 2007 to reduce the barriers to participation and offered four mini-challenges and a Grand Challenge. Mini Challenge participants were to use visual analytic tools to explore one of four heterogeneous data collections to analyze specific activities of a fictitious, controversial movement. Questions asked in the Grand Challenge required the participants to synthesize data from all four data sets. In this paper we give a brief overview of the data sets, the tasks, the participation, the judging, and the results.
Keywords: 2008; analytics; data; Challenge; heterogeneous; collections; visual; data; VAST; visualisation

VCode - Pervasive Data Transfer Using Video Barcode - Liu,Xu; David Doermann; Huiping Li (IEEETransactions on Multimedia, 2008)
In this paper we describe a novel data transfer scheme that uses the camera in a smart phone as an alternative data channel. The data is encoded as a sequence of 2D barcode images, displayed on a flat panel display, acquired by the camera, and decoded in real time by the software embedded in device. The decoded data is written to a file. Compared with existing data channels, such as CDMA/GPRS, cables, Bluetooth, and Infrared, our method relies on visual communication and does not require special hardware or data plans. Users only need to point the camera at a monitor displaying the VCode to download. Technical challenges to overcome include correction of perspective distortion, compensation for contrast variation, and efficient implementation of small footprint software into a mobile device. We address these challenges and present our solution in detail. We have implemented a prototype which allows users to download various types of files successfully, including pictures, ring tones and Java games onto camera phones running Symbian and Windows Mobile platforms. We discuss the limitations of our solution and outline future work to overcome these limitations.

Virtual access points for vehicular networks - Frangiadakis,N.; Câmara,D.; Filali,F.; Loureiro,A. A.F; Roussopoulos, Nick (Proceedings of the 1st international conference on MOBILe Wireless MiddleWARE, Operating Systems, and Applications, 2008)

Accountability as a service - Bender,Adam; Spring, Neil; Levin,Dave; Bhattacharjee, Bobby (Proceedings of the 3rd USENIX workshop on Steps to reducing unwanted traffic on the internet, 2007)
We propose that accountability be a first-class network service, independent of addressing and routing. We design a scheme for allowing accountability services, rather than connectivity-providing ISPs, to vouch for traffic, allowing victims to report abuse, filter abusive traffic, and isolate malicious senders. We discuss how accountability services may evolve, how they may facilitate new applications, and the implications of shifting the burden of network policing to a dedicated service.

An adaptive mean shift tracking method using multiscale images - Zhuolin Jiang; Li,Shao-Fa; Gao,Dong-Fa (Wavelet Analysis and Pattern Recognition, 2007. ICWAPR '07. International Conference on, 2007)
An adaptive mean shift tracking method for object tracking using multiscale images is presented in this paper. A bandwidth matrix and a Gaussian kernel are used to extend the definition of target model. The method can exactly estimate the position of the tracked object using multiscale images from Gaussian pyramid. The tracking method determines the parameters of kernel bandwidth by maximizing the lower bound of a log-likelihood function, which is derived from a kernel density estimate with the bandwidth matrix and the modified weight function. The experimental results show that it can averagely converge in 2.55 iterations per frame.
Keywords: adaptive mean shift tracking method; bandwidth matrix; Gaussian kernel; Gaussian processes; Image sequences; log-likelihood function; matrix algebra; maximum likelihood estimation; multiscale image; Object detection; object tracking

Adaptive Vocabulary Forests br Dynamic Indexing and Category Learning - Tom Yeh; Lee,John; Darrell,Trevor (Computer Vision, 2007. ICCV 2007. IEEE 11th International Conference on, 2007)
Histogram pyramid representations computed from a vocabulary tree of visual words have proven valuable for a range of image indexing and recognition tasks; however, they have only used a single, fixed partition of feature space. We present a new efficient algorithm to incrementally compute set-of-trees (forest) vocabulary representations, and show that they improve recognition and indexing performance in methods which use histogram pyramids. Our algorithm incrementally adapts a vocabulary forest with an Inverted file system at the leaf nodes and automatically keeps existing histogram pyramid database entries up-to-date in a forward filesystem. It is possible not only to apply vocabulary tree indexing algorithms directly, but also to compute pyramid match kernel values efficiently. On dynamic recognition tasks where categories or objects under consideration may change over time, we show that adaptive vocabularies offer significant performance advantages in comparison to a single, fixed vocabulary.

Algorithms for on-line monitoring of micro spheres in an optical tweezers-based assembly cell - Peng,T.; Balijepalli,A.; Gupta,S.K.; LeBrun,T. (Journal of Computing and Information Science in Engineering, 2007)
Optical tweezers have emerged as a powerful tool for microand nanomanipulation. Using optical tweezers to perform auto- mated assembly requires on-line monitoring of components in the assembly workspace. This paper presents algorithms for estimat- ing positions and orientations of microscale and nanoscale com- ponents in the 3-Dimensional assembly workspace. Algorithms presented in this paper use images obtained by optical section microscopy. The images are first segmented to locate areas of in- terest and then image gradient information from the areas of in- terest is used to generate probable locations and orientations of components in the XY-plane. Finally, signature curves are com- puted and utilized to obtain component locations and orienta- tions in 3-D space. We have tested these algorithms with silica micro-spheres as well as metallic nanowires. We believe that the algorithms described in this paper will provide the foundation for realizing automated assembly operations in optical tweezers- based assembly cells.

Amino acid quantitative structure property relationship database: a web-based platform for quantitative investigations of amino acids - Lu,Yi; Bulka,Blazej; desJardins, Marie; Freeland,Stephen J (Protein Engineering Design and SelectionProtein Engineering, Design and Selection, 2007)
Here, we present the AA-QSPR Db (Amino Acid Quantitative Structure Property Relationship Database): a novel, freely available web-resource of data pertaining to amino acids, both engineered and naturally occurring. In addition to presenting fundamental molecular descriptors of size, charge and hydrophobicity, it also includes online visualization tools for users to perform instant, interactive analyses of amino acid sub-sets in which they are interested. The database has been designed with extensible markup language technology to provide a flexible structure, suitable for future development. In addition to providing easy access for queries by external computers, it also offers a user-friendly web-based interface that facilitates human interactions (submission, storage and retrieval of amino acid data) and an associated e-forum that encourages users to question and discuss current and future database contents.
Keywords: Amino acids; database; QSPR; XML

Analysis of the Residual Arnoldi Method - Lee,Che-Rung; Stewart, G.W. (Instititue for Advanced Computer Studies, Univ of Maryland, College Park, 2007)
The Arnoldi method generates a nested squences of orthonormal bases$U_{1},U_{2}, …$ by orthonormalizing $Au_{k}$ against $U_{k}$. Frequently these bases contain increasingly accurate approximations of eigenparis from the periphery of the spectrum of $A$. However, the convergence of these approximations stagnates if $u_{k}$ is contaminated by error. It has been observed that if one chooses a Rayleigh--Ritz approximation $(μ_{k}, z_{k})$ to a chosen target eigenpair $(λ, x)$ and orthonormalizes the residual $Az_{k - }μ_{k} z_{k}$, the approximations to $x$ (but not the other eigenvectors) continue to converge, even when the residual is contaminated by error. The same is true of the shift-invert variant of Arnoldi's method. In this paper we give a mathematical analysis of these new methods.
Keywords: Technical Report

Answering Clinical Questions with Knowledge-Based and Statistical Techniques - Demner-Fushman,Dina; Jimmy Lin (Computational Linguistics, 2007)
The combination of recent developments in question-answering research and the availability of unparalleled resources developed specifically for automatic semantic processing of text in the medical domain provides a unique opportunity to explore complex question answering in the domain of clinical medicine. This article presents a system designed to satisfy the information needs of physicians practicing evidence-based medicine. We have developed a series of knowledge extractors, which employ a combination of knowledge-based and statistical techniques, for automatically identifying clinically relevant aspects of MEDLINE abstracts. These extracted elements serve as the input to an algorithm that scores the relevance of citations with respect to structured representations of information needs, in accordance with the principles of evidence-based medicine. Starting with an initial list of citations retrieved by PubMed, our system can bring relevant abstracts into higher ranking positions, and from these abstracts generate responses that directly answer physicians' questions. We describe three separate evaluations: one focused on the accuracy of the knowledge extractors, one conceptualized as a document reranking task, and finally, an evaluation of answers by two physicians. Experiments on a collection of real-world clinical questions show that our approach significantly outperforms the already competitive PubMed baseline.

Backbone construction in selfish wireless networks - Lee,Seungjoon; Levin,Dave; Gopalakrishnan,Vijay; Bhattacharjee, Bobby (Proceedings of the 2007 ACM SIGMETRICS international conference on Measurement and modeling of computer systems, 2007)
We present a protocol to construct routing backbones in wireless networks composed of selfish participants. Backbones are inherently cooperative, so constructing them in selfish environments is particularly difficult; participants want a backbone to exist (soothers relay their packets) but do not want to join the backbone (so they do not have to relay packets for others). We model the wireless backbone as a public good and use impatience as an incentive for cooperation. To determine if and when to donate to this public good, each participant calculates how patient it should be in obtaining the public good. We quantify patience using the Volunteer's Timing Dilemma (VTD), which we extend to general multihop network settings. Using our generalized VTD analysis, each node individually computes as its dominant strategy the amount of time to wait before joining the backbone. We evaluate our protocol using both simulations and an implementation. Our results show that, even though participants in our system deliberately wait before volunteering, a backbone is formed quickly. Further, the quality of the backbone (such as the size and resulting network lifetime) is comparable to that of existing backbone protocols that assume altruistic behavior.
Keywords: incentives; public good; selfish network; volunteer's dilemma; wireless backbone

Bio-STEER: A Semantic Web workflow tool for Grid computing in the life sciences - Lee,S.; Wang,T. D; Hashmi,N.; Cummings, Michael P. (Future Generation Comp Syst, 2007)
Life science research is becoming evermore computationally intensive. Hence, from a computational resource perspective, Grid computing provides a logical approach to meeting many of the computational needs of life science research. However, there are several barriers to the widespread use of Grid computing in life sciences. In this paper, we attempt to address one particular barrier: the difficulty of using Grid computing by life scientists. Life science research often involves connecting multiple applications together to form a workflow. This process of constructing a workflow is complex. When combined with the difficulty of using Grid services, composing a meaningful workflow using Grid services can present a challenge to life scientists. Our proposed solution is a Semantic Web-enabled computing environment, called Bio-STEER. In BioSTEER, bioinformatics Grid services are mapped to Semantic Web services, described in OWL-S. We also defined an ontology in OWL to model bioinformatics applications. A graphical user interface helps to construct a scientific workflow by showing a list of services that are semantically sound: that is, the output of one service is semantically compatible with the input of the connecting service. Bio-STEER can help users take full advantaue of Grid services through a user-friendly graphical user interface (GUI), which allows them to easily construct the workflows they need. (c) 2006 Elsevier B.V. All rights reserved.
Keywords: client/server; distributed; environments; integrated; interface; management; semantics; services; systems; user; web-base; workflow

BIPASS: BioInformatics Pipeline Alternative Splicing Services - Legendre,C.; Raschid, Louiqa; Snyder,B. (Nucleic Acids Research, 2007)

Boycotting and extorting nodes in an internetwork - Levin,D.; Bender,A.; Lumezanu,C.; Spring, Neil; Bhattacharjee, Bobby (NetE-con+ IBC, 2007)

Characterization of Ehp, a Secreted Complement Inhibitory Protein from Staphylococcus aureus - Hammel,Michal; Sfyroera,Georgia; Pyrpassopoulos,Serapion; Ricklin,Daniel; Ramyar,Kasra X.; Pop, Mihai; Jin,Zhongmin; Lambris,John D.; Geisbrecht,Brian V. (Journal of Biological Chemistry, 2007)
We report here the discovery and characterization of Ehp, a new secreted Staphylococcus aureus protein that potently inhibits the alternative complement activation pathway. Ehp was identified through a genomic scan as an uncharacterized secreted protein from S. aureus, and immunoblotting of conditioned S. aureus culture medium revealed that the Ehp protein was secreted at the highest levels during log-phase bacterial growth. The mature Ehp polypeptide is composed of 80 residues and is 44% identical to the complement inhibitory domain of S. aureus Efb (extracellular fibrinogen-binding protein). We observed preferential binding by Ehp to native and hydrolyzed C3 relative to fully active C3b and found that Ehp formed a subnanomolar affinity complex with these various forms of C3 by binding to its thioester-containing C3d domain. Site-directed mutagenesis demonstrated that Arg75 and Asn82 are important in forming the Ehp·C3d complex, but loss of these side chains did not completely disrupt Ehp/C3d binding. This suggested the presence of a second C3d-binding site in Ehp, which was mapped to the proximity of Ehp Asn63. Further molecular level details of the Ehp/C3d interaction were revealed by solving the 2.7-Å crystal structure of an Ehp·C3d complex in which the low affinity site had been mutationally inactivated. Ehp potently inhibited C3b deposition onto sensitized surfaces by the alternative complement activation pathway. This inhibition was directly related to Ehp/C3d binding and was more potent than that seen for Efb-C. An altered conformation in Ehp-bound C3 was detected by monoclonal antibody C3-9, which is specific for a neoantigen exposed in activated forms of C3. Our results suggest that increased inhibitory potency of Ehp relative to Efb-C is derived from the second C3-binding site in this new protein.

Collusion-Resistant Fingerprinting for Compressed Multimedia Signals - Varna,A.L.; He,Shan; Swaminathan,A.; M. Wu; Lu,Haiming; Lu,Zengxiang (Acoustics, Speech and Signal Processing, 2007. ICASSP 2007. IEEE International Conference on, 2007)
Most existing collusion-resistant fingerprinting techniques are for fingerprinting uncompressed signals. In this paper, we first study the performance of the traditional Gaussian based spread spectrum sequences for fingerprinting compressed signals and show that the system can be easily defeated by averaging or taking the median of a few copies. To overcome the collusion problem for compressed multimedia host signals, we propose a technique called anti-collusion dithering to mimic an uncompressed signal. Results show higher probability of catching a colluder using the proposed scheme compared to using Gaussian based fingerprints.
Keywords: based; compression; Gaussian; compression; multimedia; dithering; collusion-resistant; fingerprinting; multimedia; Gaussian; processes; data; sequences; anticollusion; signals; spectrum; spread; systems

A Component Estimation Framework for Information Forensics - Swaminathan,A.; M. Wu; Liu,K. J.R (Multimedia Signal Processing, 2007. MMSP 2007. IEEE 9th Workshop on, 2007)
With a rapid growth of imaging technologies and an increasingly widespread usage of digital images and videos for a large number of high security and forensic applications, there is a strong need for techniques to verify the source and integrity of digital data. Component forensics is new approach for forensic analysis that aims to estimate the algorithms and parameters in each component of the digital device. In this paper, we develop a novel theoretical foundation to understand the fundamental performance limits of component forensics. We define formal notions of identifiability of components in the information processing chain, and present methods to quantify the accuracies at which the component parameters can be estimated. Building upon the proposed theoretical framework, we devise methods to improve the accuracies of component parameter estimation for a wide range of forensic applications.
Keywords: component; data; data; Estimation; estimation; image; forensics; parameter; framework; digital; integrity; imaging; of; processing; security; technologies; information

COMPUTATIONAL BIOLOGY - Leparc,GG; Mitra,RD; Vardhanabhuti,S.; Wang,J.; Hannenhalli, Sridhar; Smit,S.; Widmann,J.; Knight,R.; Wu,S.; Zhang,Y.; others (Nucleic acids research, 2007)

Concept disambiguation for improved subject access using multiple knowledge sources - Sidhu,T.; Klavans,J.; Jimmy Lin (Proceedings of the Workshop on Language Technology for Cultural Heritage Data (LaTeCH 2007), 2007)
We address the problem of mining text forrelevant image metadata. Our work is situ- ated in the art and architecture domain, where highly specialized technical vocabu- lary presents challenges for NLP tech- niques. To extract high quality metadata, the problem of word sense disambiguation must be addressed in order to avoid leading the searcher to the wrong image as a result of ambiguous—and thus faulty—meta- data. In this paper, we present a disam- biguation algorithm that attempts to select the correct sense of nouns in textual de- scriptions of art objects, with respect to a rich domain-specific thesaurus, the Art and Architecture Thesaurus (AAT). We per- formed a series of intrinsic evaluations us- ing a data set of 600 subject terms ex- tracted from an online National Gallery of Art (NGA) collection of images and text. Our results showed that the use of external knowledge sources shows an improvement over a baseline.

Concurrently-secure blind signatures without random oracles or setup assumptions - Hazay,C.; Katz, Jonathan; Koo,C. Y; Lindell,Y. (Theory of Cryptography, 2007)
We show a new protocol for blind signatures in which security is preserved even under arbitrarily-many concurrent executions. The protocol can be based on standard cryptographic assumptions and is the first to be proven secure in a concurrent setting (under any assumptions) without random oracles or a trusted setup assumption such as a common reference string. Along the way, we also introduce new definitions of security for blind signature schemes.This research was supported by US-Israel Binational Science Foundation grant #2004240. Work of the first author was also supported by an Eshkol fellowship from the Israel Ministry of Science and Technology. Work of the second author was also supported by NSF CAREER award #0447075.

Conducting In Situ Evaluations for and With Ubiquitous Computing Technologies - Consolvo,Sunny; Harrison,Beverly; Smith,Ian; Chen,Mike Y.; Everitt,Katherine; Jon Froehlich; Landay,James A. (International Journal of Human-Computer Interaction, 2007)
Abstract To evaluate ubiquitous computing technologies, which may be embedded in the environment, embedded in objects, worn, or carried by the user throughout everyday life, it is essential to use methods that accommodate the often unpredictable, real-world environments in which the technologies are used. This article discusses how we have adapted and applied traditional methods from psychology and human-computer interaction, such as Wizard of Oz and Experience Sampling, to be more amenable to the in situ evaluations of ubiquitous computing applications, particularly in the early stages of design. The way that ubiquitous computing technologies can facilitate the in situ collection of self-report data is also discussed. Although the focus is on ubiquitous computing applications and tools for their assessment, it is believed that the in situ evaluation tools that are proposed will be generally useful for field trials of other technology, applications, or formative studies that are concerned with collecting data in situ.Abstract To evaluate ubiquitous computing technologies, which may be embedded in the environment, embedded in objects, worn, or carried by the user throughout everyday life, it is essential to use methods that accommodate the often unpredictable, real-world environments in which the technologies are used. This article discusses how we have adapted and applied traditional methods from psychology and human-computer interaction, such as Wizard of Oz and Experience Sampling, to be more amenable to the in situ evaluations of ubiquitous computing applications, particularly in the early stages of design. The way that ubiquitous computing technologies can facilitate the in situ collection of self-report data is also discussed. Although the focus is on ubiquitous computing applications and tools for their assessment, it is believed that the in situ evaluation tools that are proposed will be generally useful for field trials of other technology, applications, or formative studies that are concerned with collecting data in situ.

Data Management in the Worldwide Sensor Web - Balazinska,Magdalena; Deshpande, Amol; Franklin,Michael J.; Gibbons,Phillip B.; Gray,Jim; Hansen,Mark; Liebhold,Michael; Nath,Suman; Szalay,Alexander; Tao,Vincent (IEEE Pervasive Computing, 2007)
Advances in hardware and miniaturization technologies have led to a rapid increase in the number of large-scale sensor network deployments around the world, bringing us closer to the vision of a worldwide sensor web. Exploiting the sensor web to its full potential, however, raises several hard data management challenges. Addressing these challenges requires a concerted multidisciplinary effort encompassing many computer science fields. This article outlines some of the key data management challenges of a worldwide sensor web. It also presents recent advances in data management research that aim to address these challenges. Hopefully, the scientific, ubiquitous computing, and sensor network communities will adopt some of these solutions for managing their data. The article also attempts to bring many of the remaining open issues to the attention of the database community. This article is part of a special issue on Building a Sensor-Rich World.
Keywords: data modeling; data streams; data uncertainty; distributed systems; interoperability; sensor networks

Dataflow-based mapping of computer vision algorithms onto FPGAs - Sen,M.; Corretjer,I.; Haim,F.; Saha,S.; Schlessman,J.; Lv,T.; Bhattacharyya, Shuvra S.; Wolf,W. (EURASIP Journal on Embedded Systems, 2007)

Deconstructing nuggets: the stability and reliability of complex question answering evaluation - Jimmy Lin; Zhang,Pengyi (Proceedings of the 30th annual international ACM SIGIR conference on Research and development in information retrieval, 2007)
A methodology based on "information nuggets" has recently emerged as the de facto standard by which answers to complex questions are evaluated. After several implementations in the TREC question answering tracks, the community has gained a better understanding of its many characteristics. This paper focuses on one particular aspect of the evaluation: the human assignment of nuggets to answer strings, which serves as the basis of the F-score computation. As a byproduct of the TREC 2006 ciQA task, identical answer strings were independently evaluated twice, which allowed us to assess the consistency of human judgments. Based on these results, we explored simulations of assessor behavior that provide a method to quantify scoring variations. Understanding these variations in turn lets researchers be more confident in their comparisons of systems.
Keywords: complex information needs; human judgments; trec

Diagnosing network disruptions with network-wide analysis - Huang,Yiyi; Feamster, Nick; Lakhina,Anukool; Xu,Jim (Jun) (SIGMETRICS Perform. Eval. Rev., 2007)
To maintain high availability in the face of changing network conditions, network operators must quickly detect, identify, and react to events that cause network disruptions. One way to accomplish this goal is to monitor routing dynamics, by analyzing routing update streams collected from routers. Existing monitoring approaches typically treat streams of routing updates from different routers as independent signals, and report only the "loud" events (i.e., events that involve large volume of routing messages). In this paper, we examine BGP routing data from all routers in the Abilene backbone for six months and correlate them with a catalog of all known disruptions to its nodes and links. We find that many important events are not loud enough to be detected from a single stream. Instead, they become detectable only when multiple BGP update streams are simultaneously examined. This is because routing updates exhibit network-wide dependencies. This paper proposes using network-wide analysis of routing information to diagnose (i.e., detect and identify) network disruptions. To detect network disruptions, we apply a multivariate analysis technique on dynamic routing information, (i.e., update traffic from all the Abilene routers) and find that this technique can detect every reported disruption to nodes and links within the network with a low rate of false alarms. To identify the type of disruption, we jointly analyze both the network-wide static configuration and details in the dynamic routing updates; we find that our method can correctly explain the scenario that caused the disruption. Although much work remains to make network-wide analysis of routing data operationally practical, our results illustrate the importance and potential of such an approach.
Keywords: anomaly detection; network management; statistical inference

Document Image Mosaicing with Mobile Phones - Hannuksela,J.; Sangi,P.; Heikkila,J.; Liu,X.; David Doermann (International Conference on Image Analysis and Processing (ICIAP'07), 2007)
This paper presents a novel user interaction oncept for document image scanning with mobile phones. A high resolution mosaic image is constructed in two main stages. Firstly, online camera motion estimation is applied on the phone to assist the user to capture small image batches of the document page. Automatic image stitching process with a help of estimated device motion is carried out to reconstruct the full view of the document. Experiments on document images captured and processed with the mosaicing software clearly show the feasibility of the approach.

Draft Genome of the Filarial Nematode Parasite Brugia Malayi - Ghedin,Elodie; Wang,Shiliang; Spiro,David; Caler,Elisabet; Zhao,Qi; Crabtree,Jonathan; Allen,Jonathan E; Delcher,Arthur L.; Guiliano,David B; Miranda-Saavedra,Diego; Angiuoli,Samuel V; Creasy,Todd; et al. (Science, 2007)
Parasitic nematodes that cause elephantiasis and river blindness threaten hundreds of millions of people in the developing world. We have sequenced the ∼90 megabase (Mb) genome of the human filarial parasite Brugia malayi and predict ∼11,500 protein coding genes in 71 Mb of robustly assembled sequence. Comparative analysis with the free-living, model nematode Caenorhabditis elegans revealed that, despite these genes having maintained little conservation of local synteny during ∼350 million years of evolution, they largely remain in linkage on chromosomal units. More than 100 conserved operons were identified. Analysis of the predicted proteome provides evidence for adaptations of B. malayi to niches in its human and vector hosts and insights into the molecular basis of a mutualistic relationship with its Wolbachia endosymbiont. These findings offer a foundation for rational drug design.

An ease-of-use stereo-based particle filter for tracking under occlusion - Lim,S.N.; Davis, Larry S. (Human Motion–Understanding, Modeling, Capture and Animation, 2007)
We describe a tracker that handles occlusion by clustering foreground pixels based on their disparity values. Stereo-matched foreground pixels, mapped from multiple views to a reference view, allow the tracker to recover occluded foreground regions in the reference view. The stereo algorithm utilizes a common plan view into which foreground regions from multiple views are projected and intersected to construct polygons that contain the ground plane locations of objects, followed by constraining the epipolar search to only those pixels with ground plane locations lying within these polygons. Consequently, a stereo-matched foreground pixel is easily mapped between views by first mapping its ground plane location using pre-computed homography, followed by intersecting the vertical axis passing through the mapped location with the epipolar line. Finally, tracking in a reference view allows a particle filter to be “seamlessly” integrated, so that uncertainties can be effectively dealt with. Experimental results illustrate the effectiveness of our algorithm.

EcoLens: Integration and interactive visualization of ecological datasets - Parr,Cynthia Sims; Lee,Bongshin; Bederson, Benjamin B. (Ecological Informatics, 2007)
Complex multi-dimensional datasets are now pervasive in science and elsewhere in society. Better interactive tools are needed for visual data exploration so that patterns in such data may be easily discovered, data can be proofread, and subsets of data can be chosen for algorithmic analysis. In particular, synthetic research such as ecological interaction research demands effective ways to examine multiple datasets. This paper describes our integration of hundreds of food-web datasets into a common platform, and the visualization software, EcoLens, we developed for exploring this information. This publicly-available application and integrated dataset have been useful for our research predicting large complex food webs, and EcoLens is favorably reviewed by other researchers. Many habitats are not well represented in our large database. We confirm earlier results about the small size and lack of taxonomic resolution in early food webs but find that they and a non-food-web source provide trophic information about a large number of taxa absent from more modern studies. Corroboration of Tuesday Lake trophic links across studies is usually possible, but lack of links among congeners may have several explanations. While EcoLens does not provide all kinds of analytical support, its label- and item-based approach is effective at addressing concerns about the comparability and taxonomic resolution of food-web data.
Keywords: Data integration; Food webs; Taxonomy; Visualization

Evaluating a cross-cultural children’s online book community: Lessons learned for sociability, usability, and cultural exchange - Komlodi,Anita; Hou,Weimin; Preece,Jenny; Druin, Allison; Golub,Evan; Alburo,Jade; Liao,Sabrina; Elkiss,Aaron; Resnik, Philip (Interacting with Computers, 2007)
The use of computers for human-to-human communication among adults has been studied for many years, but using computer technology to enable children from all over the world to talk to each other has rarely been discussed by researchers. The goal of our research is to fill this gap and explore the design and evaluation of children’s cross-language online communities via a case study of the International Children’s Digital Library Communities (ICDLCommunities). This project supports the development of communities for children (ages 7–11) that form around the International Digital Children’s Library (ICDL) book collection. In this community the children can learn about each others’ cultures and make friends even if they do not speak the same language. They can also read and create stories and ask and answer questions about these. From this evaluation study we learned that: (i) children are very interested in their counterparts in other countries and a remarkable amount of communication takes place even when they do not share a common language; (ii) representing their identity online in many different forms is particularly important to children when communicating in an online community; (iii) children enjoy drawing but representing stories in a sequence of diagrams is challenging and needs support; and (iv) asking and answering questions without language is possible using graphical templates. In this paper we present our findings and make recommendations for designing children’s cross-cultural online communities.
Keywords: children; Cross-cultural; Evaluation and design; International Children’s Digital Library; Online communities

Evolution of genes and genomes on the Drosophila phylogeny - Clark,Andrew G.; Eisen,Michael B.; Smith,Douglas R.; Bergman,Casey M.; Oliver,Brian; Markow,Therese A.; Kaufman,Thomas C.; Kellis,Manolis; Gelbart,William; Iyer,Venky N.; Pollard,Daniel A.; Sackton,Timothy B.; et al. (Nature, 2007)
Comparative analysis of multiple genomes in a phylogenetic framework dramatically improves the precision and sensitivity of evolutionary inference, producing more robust results than single-genome analyses can provide. The genomes of 12 Drosophila species, ten of which are presented here for the first time (sechellia, simulans, yakuba, erecta, ananassae, persimilis, willistoni, mojavensis, virilis and grimshawi), illustrate how rates and patterns of sequence divergence across taxa can illuminate evolutionary processes on a genomic scale. These genome sequences augment the formidable genetic tools that have made Drosophila melanogaster a pre-eminent model for animal genetics, and will further catalyse fundamental research on mechanisms of development, cell biology, genetics, disease, neurobiology, behaviour, physiology and evolution. Despite remarkable similarities among these Drosophila species, we identified many putatively non-neutral changes in protein-coding genes, non-coding RNA genes, and cis-regulatory regions. These may prove to underlie differences in the ecology and behaviour of these diverse species.

Experimenting with software testbeds for evaluating new technologies - Lindvall,M.; Rus,I.; Donzelli,P.; Memon, Atif M.; Zelkowitz, Marvin V; Betin-Can,A.; Bultan,T.; Ackermann,C.; Anders,B.; Asgari, S.; Basili, Victor R. (Empirical Software Engineering, 2007)
The evolution of a new technology depends upon a good theoretical basis for developing the technology, as well as upon its experimental validation. In order to provide for this experimentation, we have investigated the creation of a software testbed and the feasibility of using the same testbed for experimenting with a broad set of technologies. The testbed is a set of programs, data, and supporting documentation that allows researchers to test their new technology on a standard software platform. An important component of this testbed is the Unified Model of Dependability (UMD), which was used to elicit dependability requirements for the testbed software. With a collection of seeded faults and known issues of the target system, we are able to determine if a new technology is adept at uncovering defects or providing other aids proposed by its developers. In this paper, we present the Tactical Separation Assisted Flight Environment (TSAFE) testbed environment for which we modeled and evaluated dependability requirements and defined faults to be seeded for experimentation. We describe two completed experiments that we conducted on the testbed. The first experiment studies a technology that identifies architectural violations and evaluates its ability to detect the violations. The second experiment studies model checking as part of design for verification. We conclude by describing ongoing experimental work studying testing, using the same testbed. Our conclusion is that even though these three experiments are very different in terms of the studied technology, using and re-using the same testbed is beneficial and cost effective.

An exploration of the principles underlying redundancy-based factoid question answering - Jimmy Lin (ACM Transactions on Information Systems, 2007)
The so-called “redundancy-based” approach to question answering represents a successful strategy for mining answers to factoid questions such as “Who shot Abraham Lincoln?” from the World Wide Web. Through contrastive and ablation experiments with Aranea, a system that has performed well in several TREC QA evaluations, this work examines the underlying assumptions and principles behind redundancy-based techniques. Specifically, we develop two theses: that stable characteristics of data redundancy allow factoid systems to rely on external “black box” components, and that despite embodying a data-driven approach, redundancy-based methods encode a substantial amount of knowledge in the form of heuristics. Overall, this work attempts to address the broader question of “what really matters” and to provide guidance for future researchers.
Keywords: Data redundancy; Web search

A fast implementation of the ISODATA clustering algorithm - Memarsadeghi,N.; Mount, Dave; Netanyahu,N. S; Le Moigne,J.; de Berg,M. (International Journal of Computational Geometry and Applications, 2007)
Clustering is central to many image processing and remote sensing applications. isodatais one of the most popular and widely used clustering methods in geoscience applications, but it can run slowly, particularly with large data sets. We present a more efficient approach to isodata clustering, which achieves better running times by storing the points in a kd-tree and through a modification of the way in which the algorithm estimates the dispersion of each cluster. We also present an approximate version of the algorithm which allows the user to further improve the running time, at the expense of lower fidelity in computing the nearest cluster center to each point. We provide both theoretical and empirical justification that our modified approach produces clusterings that are very similar to those produced by the standard isodata approach. We also provide empirical studies on both synthetic data and remotely sensed Landsat and MODIS images that show that our approach has significantly lower running times.

Fast Time-Domain Spherical Microphone Array Beamforming - Zhiyun Li; Duraiswami, Ramani (Applications of Signal Processing to Audio and Acoustics, 2007 IEEE Workshop on, 2007)
Capturing and reproducing 3D audio has several applications. Spherical array based beamforming is an important technique in this field. However, such a beamformer is very expensive to implement, especially for interactive applications. In this paper, we propose a fast spherical beamforming algorithm in the time domain. It uses pre-computed data and can be steered to arbitrary 3D directions. It is ideal for interactive audio applications such as 3D games, etc. Simulation and experimental results are demonstrated to verify our algorithm.

Flexible and Optimal Design of Spherical Microphone Arrays for Beamforming - Li,Z.; Duraiswami, Ramani (Audio, Speech, and Language Processing, IEEE Transactions on, 2007)
This paper describes a methodology for designing a flexible and optimal spherical microphone array for beamforming. Using the approach presented, a spherical microphone array can have very flexible layouts of microphones on the spherical surface, yet optimally approximate a desired beampattern of higher order within a specified robustness constraint. Depending on the specified beampattern order, our approach automatically achieves optimal performances in two cases: when the specified beampattern order is reachable within the robustness constraint we achieve a beamformer with optimal approximation of the desired beampattern; otherwise we achieve a beamformer with maximum directivity, both robustly. For efficient implementation, we also developed an adaptive algorithm for computing the beamformer weights. It converges to the optimal performance quickly while exactly satisfying the specified frequency response and robustness constraint in each step. One application of the method is to allow the building of a real-world system, where microphones may not be placeable on regions, such as near cable outlets and/or a mounting base, while having a minimal effect on the performance. Simulation results are presented
Keywords: adaptive; algorithm; beamforming; beampattern; frequency; arrays; arrays; acoustic; directivity; optimal; microphone; processing; array; processing; microphone; response; maximum; signal; spherical

GATA and Nkx factors synergistically regulate tissue-specific gene expression and development in vivo - Zhang,Yuzhen; Rath,Nibedita; Hannenhalli, Sridhar; Wang,Zhishan; Cappola,Thomas; Kimura,Shioko; Atochina-Vasserman,Elena; Lu,Min Min; Beers,Michael F.; Morrisey,Edward E. (Development, 2007)
In vitro studies have suggested that members of the GATA and Nkx transcription factor families physically interact, and synergistically activate pulmonary epithelial- and cardiac-gene promoters. However, the relevance of this synergy has not been demonstrated in vivo. We show that Gata6-Titf1 (Gata6-Nkx2.1) double heterozygous (G6-Nkx DH) embryos and mice have severe defects in pulmonary epithelial differentiation and distal airway development, as well as reduced phospholipid production. The defects in G6-Nkx DH embryos and mice are similar to those observed in human neonates with respiratory distress syndromes, including bronchopulmonary dysplasia, and differential gene expression analysis reveals essential developmental pathways requiring synergistic regulation by both Gata6 and Titf1 (Nkx2.1). These studies indicate that Gata6 and Nkx2.1 act in a synergistic manner to direct pulmonary epithelial differentiation and development in vivo, providing direct evidence that interactions between these two transcription factor families are crucial for the development of the tissues in which they are co-expressed.

Hierarchical Part-Template Matching for Human Detection and Segmentation - Zhe Lin; Davis, Larry S.; David Doermann; DeMenthon,D. (Computer Vision, 2007. ICCV 2007. IEEE 11th International Conference on, 2007)
Local part-based human detectors are capable of handling partial occlusions efficiently and modeling shape articulations flexibly, while global shape template-based human detectors are capable of detecting and segmenting human shapes simultaneously. We describe a Bayesian approach to human detection and segmentation combining local part-based and global template-based schemes. The approach relies on the key ideas of matching a part-template tree to images hierarchically to generate a reliable set of detection hypotheses and optimizing it under a Bayesian MAP framework through global likelihood re-evaluation and fine occlusion analysis. In addition to detection, our approach is able to obtain human shapes and poses simultaneously. We applied the approach to human detection and segmentation in crowded scenes with and without background subtraction. Experimental results show that our approach achieves good performance on images and video sequences with severe occlusion.
Keywords: analysis; global; approach; background; articulations; video; Bayesian; detection; human; detectors; hierarchical; detectors; partial; framework; Bayesian; human; likelihood; MAP; matching; human; matching; image; methods; image; occlusion; occlusions; shape; part-based; part-template; re-evaluation; global; segmentation; image; segmentation; local; sequences; sequences; Bayes; SHAPE; subtraction; fine; template-based