Incorporating manufacturability considerations during design of injection molded multi-material objects - Banerjee,Ashis; Li,Xuejun; Fowler,Greg; Gupta, Satyandra K. (Research in Engineering Design, 2007)
The presence of an already molded component during the second and subsequent molding stages makes multi-material injection molding different from traditional injection molding process. Therefore, designing multi-material molded objects requires addressing many additional manufacturability considerations. In this paper, we first present an approach to systematically identifying potential manufacturability problems that are unique to the multi-material molding processes and design rules to avoid these problems. Then we present a comprehensive manufacturability analysis approach that incorporates both the traditional single material molding rules as well as the specific rules that have been identified for multi-material molding. Our analysis shows that sometimes the traditional rules need to be suppressed or modified. Lastly, for each of the new manufacturability problem, this paper describes algorithms for automatically detecting potential occurrences and generating redesign suggestions. These algorithms have been implemented in a computer-aided manufacturability analysis system. The approach presented in this paper is applicable to multi-shot and over molding processes. We expect that the manufacturability analysis techniques presented in this paper will help in decreasing the product development time for the injection molded multi-material objects.
Keywords: engineering

Increasing the breadth: applying sensors, inference and self-report in field studies with the MyExperience tool - Jon Froehlich; Chen,Mike Y.; Consolvo,Sunny; Harrison,Beverly; Landay,James A. (Proceedings of the 1st international workshop on System evaluation for mobile platforms, 2007)
Keywords: In situ evaluation; context-aware systems; experience sampling method (ESM); field studies; Mobile computing; toolkits

An Interactive Approach to Pose-Assisted and Appearance-based Segmentation of Humans - Zhe Lin; Davis, Larry S.; David Doermann; DeMenthon,D. (Computer Vision, 2007. ICCV 2007. IEEE 11th International Conference on, 2007)
An interactive human segmentation approach is described. Given regions of interest provided by users, the approach iteratively estimates segmentation via a generalized EM algorithm. Specifically, it encodes both spatial and color information in a nonparametric kernel density estimator, and incorporates local MRF constraints and global pose inferences to propagate beliefs over image space iteratively to determine a coherent segmentation. This ensures the segmented humans resemble the shapes of human poses. Additionally, a layered occlusion model and a probabilistic occlusion reasoning method are proposed to handle segmentation of multiple humans in occlusion. The approach is tested on a wide variety of images containing single or multiple occluded humans, and the segmentation performance is evaluated quantitatively.
Keywords: algorithm; appearance-based; algorithm; hidden; approach; layered; density; EM; Estimation; estimation; estimator; pose-assisted; feature; human; Kernel; mechanisms; pose; method; expectation-maximisation; model; nonparametric; occlusion; reasoning; removal; image; segmentation; inference; segmentation; interactive; segmentation; probabilistic

Intrinsic fingerprints for image authentication and steganalysis - Swaminathan,A.; Wu,M.; Liu,K. J.R (Proc. SPIE Conf. Security, Steganography, Watermarking of Multimedia Contents, 2007)
With growing popularity of digital imaging devices and low-cost image editing software, the integrity of imagecontent can no longer be taken for granted. This paper introduces a methodology for forensic analysis of digital camera images, based on the observation that many in-camera and post-camera processing operations leave distinct traces on digital images. We present methods to identify these intrinsic fingerprint traces of the various processing operations and employ them to verify the authenticity of digital data. We develop an explicit imaging model to characterize the properties that should be satisfied by a direct camera output, and model any further processing applied to the camera captured image by a manipulation filter. Utilizing the manipulation filter coefficients and reference patterns estimated from direct camera outputs using blind deconvolution techniques, the proposed methods are capable of detecting manipulations made by previously unseen operations and steganographic embedding.

Joint Uplink and Downlink Optimization for Real-Time Multiuser Video Streaming Over WLANs - Su,Guan-Ming; Han,Zhu; M. Wu; Liu,K. J.R (Selected Topics in Signal Processing, IEEE Journal of, 2007)
In this paper, a network-aware and source-aware video streaming system is proposed to support interactive multiuser communications within single-cell and multicell IEEE 802.11 networks. Unlike the traditional streaming video services, the strict delay constraints of an interactive video streaming system pose more challenges. These challenges include the heterogeneity of uplink and downlink channel conditions experienced by different users, the multiuser resource allocation of limited radio resources, the incorporation of the cross-layer design, and the diversity of content complexities exhibited by different video sequences. With the awareness of video content and network resources, the proposed system integrates cross-layer error protection mechanism and performs dynamic resource allocation across multiple users. We formulate the proposed system as to minimize the maximal end-to-end expected distortion received by all users, subject to maximal transmission power and delay constraints. To reduce the high dimensionality of the search space, fast multiuser algorithms are proposed to find the near-optimal solutions. Compared to the strategy without dynamically and jointly allocating bandwidth resource for uplinks and downlinks, the proposed framework outperforms by 2.18 7.95 dB in terms of the average received PSNR of all users and by 3.82 11.50 dB in terms of the lowest received PSNR among all users. Furthermore, the proposed scheme can provide more uniform video quality for all users and lower quality fluctuation for each received video sequence.
Keywords: 802.11; allocation; image; allocation; real-time; communications; maximal; distortion; multiuser; end-to-end; error; expected; IEEE; LAN; mechanism; downlink; multiuser; networks; WLAN; cross-layer; optimization; interactive; optimization; video; Protection; quality; video; resource; sequences; video; streaming; streaming; uplink; streaming; wireless; system; bandwidth; video

Markerless Monocular Tracking of Articulated Human Motion - Liu,Haiying; Chellapa, Rama (Acoustics, Speech and Signal Processing, 2007. ICASSP 2007. IEEE International Conference on, 2007)
This paper presents a method for tracking general 3D general articulated human motion using a single camera with unknown calibration data. No markers, special clothes, or devices are assumed to be attached to the subject. In addition, both the camera and the subject are allowed to move freely, so that long-term view-independent human motion tracking and recognition are possible. We exploit the fact that the anatomical structure of the human body can be approximated by an articulated blob model. The optical flow under scaled orthographic projection is used to relate the spatial-temporal intensity change of the image sequence to the human motion parameters. These motion parameters are obtained by solving a set of linear equations to achieve global optimization. The correctness and robustness of the proposed method are demonstrated using Tai Chi sequences
Keywords: analysis; image; blob; camera; spatial-temporal; Chi; equations; markerless; flow; scaled; human; intensity; cameras; gait; model; articulated; monocular; MOTION; motion; global; optimization; human; orthographic; projection; single; recognition; image; sequence; linear; sequences; anatomical; sequences; optimisation; structure; articulated; Tai; tracking; optical

Microarray analysis of gene expression induced by sexual contact in Schistosoma mansoni - Waisberg,Michael; Lobo,Francisco; Cerqueira,Gustavo; Passos,Liana; Carvalho,Omar; Franco,Gloria; El‐Sayed, Najib M. (BMC Genomics, 2007)
BACKGROUND:The parasitic trematode Schistosoma mansoni is one of the major causative agents of Schistosomiasis, a disease that affects approximately 200 million people, mostly in developing countries. Since much of the pathology is associated with eggs laid by the female worm, understanding the mechanisms involved in oogenesis and sexual maturation is an important step towards the discovery of new targets for effective drug therapy. It is known that the adult female worm only develops fully in the presence of a male worm and that the rates of oviposition and maturation of eggs are significantly increased by mating. In order to study gene transcripts associated with sexual maturation and oviposition, we compared the gene expression profiles of sexually mature and immature parasites using DNA microarrays.RESULTS:For each experiment, three amplified RNA microarray hybridizations and their dye swaps were analyzed. Our results show that 265 transcripts are differentially expressed in adult females and 53 in adult males when mature and immature worms are compared. Of the genes differentially expressed, 55% are expressed at higher levels in paired females while the remaining 45% are more expressed in unpaired ones and 56.6% are expressed at higher levels in paired male worms while the remaining 43.4% are more expressed in immature parasites. Real-time RT-PCR analysis validated the microarray results. Several new maturation associated transcripts were identified. Genes that were up-regulated in single-sex females were mostly related to energy generation (i.e. carbohydrate and protein metabolism, generation of precursor metabolites and energy, cellular catabolism, and organelle organization and biogenesis) while genes that were down-regulated related to RNA metabolism, reactive oxygen species metabolism, electron transport, organelle organization and biogenesis and protein biosynthesis.CONCLUSION:Our results confirm previous observations related to gene expression induced by sexual maturation in female schistosome worms. They also increase the list of S. mansoni maturation associated transcripts considerably, therefore opening new and exciting avenues for the study of the conjugal biology and development of new drugs against schistosomes.

MobCast: Overlay Architecture for Seamless IP Mobility using Scalable Anycast Proxies - Lee,C.P.; Attrey,K.; Caballero,C.; Feamster, Nick; Mihail,M.; Copeland,J.A. (Wireless Communications and Networking Conference, 2007.WCNC 2007. IEEE, 2007)
We propose a routing overlay system, MobCast, for simple and efficient routing to mobile hosts. Mobcast nodes advertise the same address space at each proxy location, and each mobile host is assigned a "universal" IP address from this address space, so packets sent to a mobile host's universal IP address automatically go to the nearest proxy on the overlay. The overlay then delivers the packets to the mobile host. Our architecture enables seamless mobility for both micro and macro mobility. While our initial design is not as mature as Mobile IP, it shows great promise to solve the traditional problems of ingress routing, firewalls, NATs, and rapid mobility with much lower complexity. We present our design as a scalable and deployable alternative to mobile IP. In this paper, we focus on describing the MobCast system architecture. We form our arguments for scalability, handoff-speed, and simplicity, and give our initial results for scalability. We postpone a detailed discussion of MobCast's security model for future work.
Keywords: address space; handoff-speed; IP networks; MobCast; mobile hosts; mobile radio; overlay architecture; proxy location; routing overlay system; scalable anycast proxies; seamless IP mobility; telecommunication network routing; universal IP address

Mobile Retriever - Finding Document with a Snapshot - Liu,Xu; David Doermann (CBDAR, 2007)
In this paper we describe a camera based document image retrieval system which is targeted toward camera phones. Our goal is to enable the device to identify which of a known set of documents it is “looking at”. This paper provides two key contributions 1) a local context descriptor that effectively rules out irrelevant documents using only a small patch of the document image and 2) a layout verification approach that boosts the accuracy of retrieval even under severe degradation such as warping or crinkling. We have implemented the mobile retriever client on an iMate Jamin camera phone and tested it with a document database of 12742 pages. Experiments show that our verification approach clearly separates successful retrievals from unsuccessful retrievals.

Models for advancing PRAM and other algorithms into parallel programs for a PRAM-On-Chip platform - Vishkin, Uzi; Caragea,George C.; Lee,Bryant (IN HANDBOOK OF PARALLEL COMPUTING: MODELS, ALGORITHMS AND APPLICATIONS, EDITORS, 2007)
A bold vision that guided this work is as follows: (i) a parallel algorithms and programming course could become a standard course in every undergraduate computer science program, and (ii) this course could be coupled with a so-called PRAM-On-Chip architecture — a commodity high-end multi-core computer architecture. In fact, the current paper is a tutorial on how to convert PRAM algorithms intoefficient PRAM-On-Chip programs. Coupled with a text on PRAM algorithms as well as an available PRAM-On-Chip tool-chain, comprising a compiler and a simulator, the paper provides the missing link for upgrading a standard theoretical PRAM algorithms class to a parallel algorithms and programming class. Having demonstrated that such a course could cover similar programming projects and material to what is covered by a typical ﬁrst serial algorithms and programming course, the paper suggests that parallel programming in the emerging multi-core era does not need to be more diﬃcult than serial programming. If true, a powerful answer to the so-called parallel programming open problem is being provided. This open problem is currently the main stumbling block for the industry in getting the upcoming generation of multi-core architectures to improve single task completion time using easy-to-program application programmer interfaces. Known constraints of this open problem, such as backwards compatibility on serial code, are also addressed by the overall approach. More concretely, a widely used methodology for advancing parallel algorithmic thinking into parallel algorithms is revisited, and is extended into a methodology for advancing parallel algorithms to PRAM-On-Chip programs. A performance cost model for the PRAM-On-Chip is also presented. It uses as complexity metrics the length of sequence of round trips to memory (LSRTM) and queuing delay (QD) from memory access queues, in addition to standard PRAM computation costs. Highlighting the importance of LSRTM in determining performance is another contribution of the paper. Finally, some alternatives to PRAM algorithms, which, on one hand, are easier-to-think, but, on the other hand, suppress more architecture details, are also discussed.

Multi-candidate reduction: Sentence compression as a tool for document summarization tasks - Zajic, David; Dorr, Bonnie J; Jimmy Lin; Schwartz,Richard (Information Processing & Management, 2007)
This article examines the application of two single-document sentence compression techniques to the problem of multi-document summarization—a “parse-and-trim” approach and a statistical noisy-channel approach. We introduce the multi-candidate reduction (MCR) framework for multi-document summarization, in which many compressed candidates are generated for each source sentence. These candidates are then selected for inclusion in the final summary based on a combination of static and dynamic features. Evaluations demonstrate that sentence compression is a valuable component of a larger multi-document summarization framework.
Keywords: Headline generation; Hidden Markov model; Parse-and-trim; Summarization

Multiple alternative sentence compressions for automatic text summarization - Madnani,N.; Zajic, David; Dorr, Bonnie J; Ayan,N.F.; Jimmy Lin (Proceedings of DUC, 2007)
We perform multi-document summariza-tion by generating compressed versions of source sentences as summary candi- dates and using weighted features of these candidates to construct summaries. We combine a parse-and-trim approach with a novel technique for producing multiple alternative compressions for source sen- tences. In addition, we use a novel method for tuning the feature weights that maxi- mizes the change in the ROUGE-2 score (∆ROUGE) between the already existing summary state and the new state that re- sults from the addition of the candidate under consideration. We also describe ex- periments using a new paraphrase-based feature for redundancy checking. Finally, we present the results of our DUC2007 submissions and some ideas for future work.

MyExperience: a system for in situ tracing and capturing of user feedback on mobile phones - Jon Froehlich; Chen,Mike Y.; Consolvo,Sunny; Harrison,Beverly; Landay,James A. (Proceedings of the 5th international conference on Mobile systems, applications and services, 2007)
This paper presents MyExperience, a system for capturing both objective and subjective in situ data on mobile computing activities. MyExperience combines the following two techniques: 1) passive logging of device usage, user context, and environmental sensor readings, and 2) active context-triggered user experience sampling to collect in situ, subjective user feedback. MyExperience currently runs on mobile phones and supports logging of more than 140 event types, including: 1) device usage such as communication, application usage, and media capture, 2) user context such as calendar appointments, and 3) environmental sensing such as Bluetooth and GPS. In addition, user experience sampling can be targeted to moments of interest by triggering off sensor readings. We present several case studies of field deployments on people's personal phones to demonstrate how MyExperience can be used effectively to understand how people use and experience mobile technology.
Keywords: context-aware systems; experience sampling method (ESM); field studies; in situ evaluation; Mobile computing; SmartPhones; toolkit; usage logging; user surveys; user-centered design

NetLens: Iterative Exploration of Content-Actor Network Data - Kang,Hyunmo; Plaisant, Catherine; Lee,Bongshin; Bederson, Benjamin B. (Information VisualizationInformation Visualization, 2007)
Networks have remained a challenge for information retrieval and visualization because of the rich set of tasks that users want to accomplish. This paper offers an abstract Content-Actor network data model, a classification of tasks, and a tool to support them. The NetLens interface was designed around the abstract Content-Actor network data model to allow users to pose a series of elementary queries and iteratively refine visual overviews and sorted lists. This enables the support of complex queries that are traditionally hard to specify. NetLens is general and scalable in that it applies to any data set that can be represented with our abstract data model. This paper describes the use of NetLens with a subset of the ACM Digital Library consisting of about 4000 papers from the CHI conference written by about 6000 authors, and reports on a usability study with nine participants.
Keywords: content-actor network data; digital library; incremental data exploration; iterative query refinement; User interfaces

NetLens: iterative exploration of content-actor network data - Kang,H.; Plaisant, Catherine; Lee,B.; Bederson, Benjamin B. (Information Visualization, 2007)

New Trypanosoma cruzi Repeated Element That Shows Site Specificity for Insertion - Souza,Renata T.; Santos,Marcia R. M.; Lima,Fabio M.; El‐Sayed, Najib M.; Myler,Peter J.; Ruiz,Jeronimo C.; da Silveira,Jose Franco (Eukaryotic Cell, 2007)
A new family of site-specific repeated elements identified in Trypanosoma cruzi, which we named TcTREZO, is described here. TcTREZO appears to be a composite repeated element, since three subregions may be defined within it on the basis of sequence similarities with other T. cruzi sequences. Analysis of the distribution of TcTREZO in the genome clearly indicates that it displays site specificity for insertion. Most TcTREZO elements are flanked by conserved sequences. There is a highly conserved 68-bp sequence at the 5' end of the element and a sequence domain of [~]500 bp without a well-defined borderline at the 3' end. Northern blot hybridization and reverse transcriptase PCR analyses showed that TcTREZO transcripts are expressed as oligo(A)-terminated transcripts whose length corresponds to the unit size of the element (1.6 kb). Transcripts of [~]0.2 kb derived from a small part of TcTREZO are also detected in steady-state RNA. TcTREZO transcripts are unspliced and not translated. The copy number of TcTREZO sequences was estimated to be [~]173 copies per haploid genome. TcTREZO appears to have been assembled by insertions of sequences into a progenitor element. Once associated with each other, these subunits were amplified as a new transposable element. TcTREZO shows site specificity for insertion, suggesting that a sequence-specific endonuclease could be responsible for its insertion at a unique site.

Nonintrusive component forensics of visual sensors using output images - Swaminathan,A.; M. Wu; Liu,K. J.R (Information Forensics and Security, IEEE Transactions on, 2007)
Rapid technology development and the widespread use of visual sensors have led to a number of new problems related to protecting intellectual property rights, handling patent infringements, authenticating acquisition sources, and identifying content manipulations. This paper introduces nonintrusive component forensics as a new methodology for the forensic analysis of visual sensing information, aiming to identify the algorithms and parameters employed inside various processing modules of a digital device by only using the device output data without breaking the device apart. We propose techniques to estimate the algorithms and parameters employed by important camera components, such as color filter array and color interpolation modules. The estimated interpolation coefficients provide useful features to construct an efficient camera identifier to determine the brand and model from which an image was captured. The results obtained from such component analysis are also useful to examine the similarities between the technologies employed by different camera models to identify potential infringement/licensing and to facilitate studies on technology evolution
Keywords: ACQUISITION; array; color; authenticating; component; filter; forensics; patent; infringements; visual; Interpolation; manipulations; intellectual; modules; content; property; property; protection; nonintrusive; rights; sensors; image; sensors; industrial; sources; color

Object Detection Using Shape Codebook - Yu,Xiaodong; Li,Yi; Fermüller, Cornelia; David Doermann (British Machine Vision Conference (BMVC'07), 2007)
This paper presents a method for detecting categories of objects in real-world images. Given training images of an object category, our goal is to recognize and localize instances of those objects in a candidate image. The main contribution of this work is a novel structure of the shape codebook for object detection. A shape codebook entry consists of two components: a shape codeword and a group of associated vectors that specify the object centroids. Like their counterpart in language, the shape codewords are simple and generic such that they can be easily extracted from most object categories. The associated vectors store the geometrical relationships between the shape codewords, which specify the characteristics of a particular object category. Thus they can be considered as the “grammar” of the shape codebook. In this paper, we use Triple-Adjacent-Segments (TAS) extracted from image edges as the shape codewords. Object detection is performed in a probabilistic voting framework. Experimental results on public datasets show performance similar to the state-of-the-art, yet our method has significantly lower complexity and requires considerably less supervision in the training (We only need bounding boxes for a few training samples, do not need figure/ground segmentation and do not need a validation dataset).

Oblivious routing on node-capacitated and directed graphs - Hajiaghayi, Mohammad T.; Kleinberg,R. D; R\äcke,H.; Leighton,T. (ACM Transactions on Algorithms (TALG), 2007)

PeerWise discovery and negotiation of faster paths - Lumezanu,C.; Levin,D.; Spring, Neil (Proc. Workshop on Hot Topics in Networks (HotNets), 2007)

Poster Session 5: Matching and Registration-Simultaneous Appearance Modeling and Segmentation for Matching People Under Occlusion - Lin,Z.; Davis, Larry S.; David Doermann; DeMenthon,D. (Lecture Notes in Computer Science, 2007)

Predicting Protein-Protein Interactions Using Relational Features - Licamele,Louis; Getoor, Lise (Department of Computer Science, University of Maryland, College Park, 2007)
Proteins play a fundamental role in ever y process within the cell.Understanding how proteins interact, and the functional units they are par t of, is important to furthering our knowledge of the entire biological process. There has been a growing amount of work, both experimental and computational, on determining the protein-protein interaction network. Recently researchers have had success looking at this as a relational learning problem. In this work, we further this investigation, proposing several novel relational features for predicting protein-protein interaction. These features can be used in any classifier. Our approach allows large and complex networks to be analyzed and is an alternative to using more expensive relational methods. We show that we are able to get an accuracy of 81.7% when predicting new links from noisy high throughput data.
Keywords: Technical Report

Priority and abstraction in process algebra - Cleaveland, Rance; LÃ¼ttgen,Gerald; Natarajan,V. (Information and Computation, 2007)
More than 15 years ago, Cleaveland and Hennessy proposed an extension of the process algebra CCS in which some actions may take priority over others. The theory was equipped with a behavioral congruence based on strong bisimulation.This article gives a full account of the challenges in, and the solutions employed for, defining a semantic theory of observation congruence for this process algebra. A full-abstraction result is presented whose proof relies on a novel approach based on successive approximations for identifying the largest congruence contained in an intuitive but naÃ¯ve equivalence. Prioritized observation congruence is also characterized equationally for the class of finite processes, while its utility for system verification is demonstrated by an illustrative example.
Keywords: Axiomatization; Bisimulation; Full abstraction; Observation congruence; Priority; Process algebra

Report on the Fourth International Workshop on Data Management for Sensor Networks (DMSN 2007) - Balazinska,Magdalena; Deshpande, Amol; Labrinidis,Alexandros; Luo,Qiong; Madden,Samuel; Yang,Jun (SIGMOD Rec., 2007)
Sensor networks enable an unprecedented level of access to the physical world, and hold tremendous potential to revolutionize many application domains. Research on sensor networks spans many areas of computer science, and there are now major conferences, e.g., IPSN and SenSys, devoted to sensor networks. However, there is no focused forum for discussion of early and innovative work on data management in sensor networks. The International Workshop on Data Management for Sensor Networks (DMSN), inaugurated in 2004, aims to fill this significant gap in the database and sensor network communities.

Robust Routing with Unknown Traffic Matrices - Tabatabaee,V.; Kashyap,A.; Bhattacharjee, Bobby; La,R.J.; Shayman,M.A. (INFOCOM 2007. 26th IEEE International Conference on Computer Communications. IEEE, 2007)
In this paper, we present an algorithm for intra-domain traffic engineering. We assume that the traffic matrix, which specifies traffic load between every source-destination pair in the network, is unknown and varies with time, but that always lies inside an explicitly defined region. Our goal is to compute a fixed robust routing with best worst case performance for all traffic matrices inside the bounding region. We formulate this problem as a semi-infinite programming problem. Then, we focus on a special case with practical merits, where (1) the traffic matrix region is assumed to be a polytope specified by a finite set of linear inequalities, and (2) our objective is to find the routing that minimizes the maximum link utilization. Under these assumptions, the problem can be formulated as a polynomial size linear programming (LP) problem with finite number of constraints. We further consider two specific set of constraints for the traffic matrix region. The first set is based on the hose model and limits the total traffic rate of network point of presence (PoP) nodes. The second set is based on the pipe model and limits the traffic between source-destination pairs. We study the effectiveness of each set of constraints using extensive simulations.
Keywords: engineering; linear; inequalities; maximum; intradomain; linear; link; matrices; linear; matrix; network; nodes; polynomial; of; point; presence; problem; traffic; Programming; programming; semiinfinite; programming; telecommunication; region; unknown; routing; telecommunication; size; traffic; traffic; utilization; network

Schistosoma mansoni genome: Closing in on a final gene set - Haas,Brian J.; Berriman,Matthew; Hirai,Hirohisa; Cerqueira,Gustavo G.; LoVerde,Philip T.; El‐Sayed, Najib M. (Experimental Parasitology, 2007)
The Schistosoma mansoni genome sequencing consortium has recently released the latest versions of the genome assembly as well as an automated preliminary gene structure annotation. The combined datasets constitute a vast resource for researchers to exploit in a variety of post-genomic studies with an emphasis of transcriptomic and proteomic tools. Here we present an innovative method used for combining diverse sources of evidence including ab initio gene predictions, protein and transcript sequence homologies, and cross-genome sequence homologies between S. mansoni and Schistosoma japonicum to define a comprehensive list of protein-coding genes.
Keywords: Annotation; Gene finding; Genome; Schistosoma mansoni

A Secure DHT via the Pigeonhole Principle - Baden,Randy; Bender,Adam; Levin,Dave; Sherwood,Rob; Spring, Neil; Bhattacharjee, Bobby (Technical Reports of the Computer Science Department, CS-TR-4884, 2007)
The standard Byzantine attack model assumes no more than some fixedfraction of the participants are faulty. This assumption does not accurately apply to peer-to-peer settings, where Sybil attacks and botnets are realistic threats. We propose an attack model that permits an arbitrary number of malicious nodes under the assumption that each node can be classified based on some of its attributes, such as autonomous system number or operating system, and that the number of classes with malicious nodes is bounded (e.g., an attacker may exploit at most a few operating systems at a time). In this model, we present a secure DHT, evilTwin, which replaces a single, large DHT with sufficiently many smaller instances such that it is impossible for an adversary to corrupt every instance. Our system ensures high availability and low-latency lookups, is easy to implement, does not require a complex Byzantine agreement protocol, and its proof of security is a straightforward application of the pigeonhole principle. The cost of security comes in the form of increased storage and bandwidth overhead; we show how to reduce these costs by replicating data and adaptively querying participants who historically perform well. We use implementation and simulation to show that evilTwin imposes a relatively small additional cost compared to conventional DHTs.
Keywords: Technical Report

Shape Classification Using the Inner-Distance - Ling,Haibin; Jacobs, David W. (Pattern Analysis and Machine Intelligence, IEEE Transactions on, 2007)
Part structure and articulation are of fundamental importance in computer and human vision. We propose using the inner-distance to build shape descriptors that are robust to articulation and capture part structure. The inner-distance is defined as the length of the shortest path between landmark points within the shape silhouette. We show that it is articulation insensitive and more effective at capturing part structures than the Euclidean distance. This suggests that the inner-distance can be used as a replacement for the Euclidean distance to build more accurate descriptors for complex shapes, especially for those with articulated parts. In addition, texture information along the shortest path can be used to further improve shape classification. With this idea, we propose three approaches to using the inner-distance. The first method combines the inner-distance and multidimensional scaling (MDS) to build articulation invariant signatures for articulated shapes. The second method uses the inner-distance to build a new shape descriptor based on shape contexts. The third one extends the second one by considering the texture information along shortest paths. The proposed approaches have been tested on a variety of shape databases, including an articulated shape data set, MPEG7 CE-Shape-1, Kimia silhouettes, the ETH-80 data set, two leaf data sets, and a human motion silhouette data set. In all the experiments, our methods demonstrate effective performance compared with other algorithms
Keywords: Automated; Reproducibility of Results; Sensitivity and Specificity; Computer-Assisted; Imaging; Euclidean distance; articulation invariant signatures; computer vision; inner distance; multidimensional scaling; part structure; shape classification; shape descriptors; shape silhouette; shortest path; computational geometry; computer vision; graph theory; image cla; Three-Dimensional; Pattern Recognition

Simultaneous appearance modeling and segmentation for matching people under occlusion - Zhe Lin; Davis, Larry S.; David Doermann; DeMenthon,Daniel (Proceedings of the 8th Asian conference on Computer vision - Volume Part II, 2007)
We describe an approach to segmenting foreground regions corresponding to a group of people into individual humans. Given background subtraction and ground plane homography, hierarchical parttemplate matching is employed to determine a reliable set of human detection hypotheses, and progressive greedy optimization is performed to estimate the best configuration of humans under a Bayesian MAP framework. Then, appearance models and segmentations are simultaneously estimated in an iterative sampling-expectation paradigm. Each human appearance is represented by a nonparametric kernel density estimator in a joint spatial-color space and a recursive probability update scheme is employed for soft segmentation at each iteration. Additionally, an automatic occlusion reasoning method is used to determine the layered occlusion status between humans. The approach is evaluated on a number of images and videos, and also applied to human appearance matching using a symmetric distance measure derived from the Kullback-Leiber divergence.

Spliceosomal small nuclear RNA genes in 11 insect genomes - Mount, Stephen M.; Gotea,Valer; Lin,Chiao-Feng; Hernandez,Kristina; Makałowski,Wojciech (RNARNA, 2007)
A monthly journal publishing high-quality, peer-reviewed research on all topics related to RNA and its metabolism in all organisms
Keywords: honeybee; Insecta; secondary structure; snRNA; spliceosomal snRNA; U12 introns

STEWARD: architecture of a spatio-textual search engine - Lieberman,Michael D.; Samet, Hanan; Sankaranarayanan,Jagan; Sperling,Jon (Proceedings of the 15th annual ACM international symposium on Advances in geographic information systems, 2007)
STEWARD ("Spatio-Textual Extraction on the Web Aiding Retrieval of Documents"), a system for extracting, querying, and visualizing textual references to geographic locations in unstructured text documents, is presented. Methods for retrieving and processing web documents, extracting and disambiguating georeferences, and identifying geographic focus are described. A brief overview of STEWARD's querying capabilities, as well as the design of an intuitive user interface, are provided. Finally, several application scenarios and future extensions to STEWARD are discussed.
Keywords: geocoding; spatio-textual search engine; STEWARD

STEWARD: demo of spatio-textual extraction on the web aiding the retrieval of documents - Samet, Hanan; Lieberman,Michael D.; Sankaranarayanan,Jagan; Sperling,Jon (Proceedings of the 8th annual international conference on Digital government research: bridging disciplines & domains, 2007)
A spatio-textual search engine, termed "STEWARD" is demonstrated where document similarity is based on both the textual similarity as well as the spatial proximity of the locations in the document to the spatial search input. STEWARD's performance is enhanced by the presence of a document tagger that is able to identify textual references to geographical entities. The user-interface of STEWARD provides the ability to browse results, thereby making it a valuable "knowledge discovery" tool.
Keywords: geocoding; spatio-textual search engine; STEWARD

A Study of Face Recognition as People Age - Ling,Haibin; Soatto,S.; Ramanathan,N.; Jacobs, David W. (Computer Vision, 2007. ICCV 2007. IEEE 11th International Conference on, 2007)
In this paper we study face recognition across ages within a real passport photo verification task. First, we propose using the gradient orientation pyramid for this task. Discarding the gradient magnitude and utilizing hierarchical techniques, we found that the new descriptor yields a robust and discriminative representation. With the proposed descriptor, we model face verification as a two-class problem and use a support vector machine as a classifier. The approach is applied to two passport data sets containing more than 1,800 image pairs from each person with large age differences. Although simple, our approach outperforms previously tested Bayesian technique and other descriptors, including the intensity difference and gradient with magnitude. In addition, it works as well as two commercial systems. Second, for the first time, we empirically study how age differences affect recognition performance. Our experiments show that, although the aging process adds difficulty to the recognition task, it does not surpass illumination or expression as a confounding factor.
Keywords: Bayesian; difference; passport; machine; face; machines; magnitude; gradient; orientation; photo; pyramid; hierarchical; recognition; face; recognition; support; representation; face; task; support; technique; discriminative; techniques; intensity; vector; verification; verification; gradient

Surface Dependent Representations for Illumination Insensitive Image Comparison - Osadchy,M.; Jacobs, David W.; Lindenbaum,M. (Pattern Analysis and Machine Intelligence, IEEE Transactions on, 2007)
We consider the problem of matching images to tell whether they come from the same scene viewed under different lighting conditions. We show that the surface characteristics determine the type of image comparison method that should be used. Previous work has shown the effectiveness of comparing the image gradient direction for surfaces with material properties that change rapidly in one direction. We show analytically that two other widely used methods, normalized correlation of small windows and comparison of multiscale oriented filters, essentially compute the same thing. Then, we show that for surfaces whose properties change more slowly, comparison of the output of whitening filters is most effective. This suggests that a combination of these strategies should be employed to compare general objects. We discuss indications that Gabor jets use such a mixed strategy effectively, and we propose a new mixed strategy. We validate our results on synthetic and real images
Keywords: Automated; Reproducibility of Results; Sensitivity and Specificity; Subtraction Technique; Computer-Assisted; Imaging; Gabor jets; Gaussian random surface; filter whitening; illumination; image comparison; image matching; lighting condition; multiscale oriented filter; surface dependent representation; image matching; image representation; Algorithms; Artificial Intelligence; Image En; Three-Dimensional; Information Storage and Retrieval; Lighting; Pattern Recognition

Syntactic sentence compression in the biomedical domain: facilitating access to related articles - Jimmy Lin; Wilbur,W. J (Information Retrieval, 2007)
We explore a syntactic approach to sentence compression in the biomedical domain, grounded in the context of result presentation for related article search in the PubMed search engine. By automatically trimming inessential fragments of article titles, a system can effectively display more results in the same amount of space. Our implemented prototype operates by applying a sequence of syntactic trimming rules over the parse trees of article titles. Two separate studies were conducted using a corpus of manually compressed examples from MEDLINE: an automatic evaluation using Bleu and a summative evaluation involving human assessors. Experiments show that a syntactic approach to sentence compression is effective in the biomedical domain and that the presentation of compressed article titles supports accurate “interest judgments”, decisions by users as to whether an article is worth examining in more detail.

Task scheduling in large camera networks - Lim,S.N.; Davis, Larry S.; Mittal,A. (Computer Vision–ACCV 2007, 2007)
Visibility in architectural layouts affects humannavigation, so a suitable representation of visibility context is useful in understanding human activity. Motivated by studies of spatial behavior, we use a set of features from visibility analysis to represent spatial context in the interpretation of human activity. An agent’s goal, belief about the world, trajectory and visible layout are considered to be random variables that evolve with time during the agent’s movement, and are modeled in a Bayesian framework. We design a search-based task in a sprite-world, and compare the results of our framework to those of human subject experiments. Our findings confirm that knowledge of spatial layout improves human interpretations of the trajectories (implying that visibility context is useful in this task). Since our framework demonstrates performance close to that of human subjects with knowledge of spatial layout, our findings confirm that our model makes adequate use of visibility context. In addition, the representation we use for visibility context allows our model to generalize well when presented with new scenes.

Techniques for Classifying Executions of Deployed Software to Support Software Engineering Tasks - Haran,Murali; Karr,Alan; Last,Michael; Orso,Alessandro; Porter, Adam; Sanil,Ashish; Fouch?,Sandro (IEEE Transactions on Software Engineering, 2007)
There is an increasing interest in techniques that support analysis and measurement of fielded software systems. These techniques typically deploy numerous instrumented instances of a software system, collect execution data when the instances run in the field, and analyze the remotely collected data to better understand the system's in-the-field behavior. One common need for these techniques is the ability to distinguish execution outcomes (e.g., to collect only data corresponding to some behavior or to determine how often and under which condition a specific behavior occurs). Most current approaches, however, do not perform any kind of classification of remote executions and either focus on easily observable behaviors (e.g., crashes) or assume that outcomes' classifications are externally provided (e.g., by the users). To address the limitations of existing approaches, we have developed three techniques for automatically classifying execution data as belonging to one of several classes. In this paper, we introduce our techniques and apply them to the binary classification of passing and failing behaviors. Our three techniques impose different overheads on program instances and, thus, each is appropriate for different application scenarios. We performed several empirical studies to evaluate and refine our techniques and to investigate the trade-offs among them. Our results show that 1) the first technique can build very accurate models, but requires a complete set of execution data; 2) the second technique produces slightly less accurate models, but needs only a small fraction of the total execution data; and 3) the third technique allows for even further cost reductions by building the models incrementally, but requires some sequential ordering of the software instances' instrumentation.
Keywords: execution classification; remote analysis/measurement.

TREC 2007 ciQA Task: University of Maryland - Madnani,N.; Jimmy Lin; Dorr, Bonnie J (Proceedings of TREC, 2007)

User simulations for evaluating answers to question series - Jimmy Lin (Information Processing & Management, 2007)
Recently, question series have become one focus of research in question answering. These series are comprised of individual factoid, list, and “other” questions organized around a central topic, and represent abstractions of user–system dialogs. Existing evaluation methodologies have yet to catch up with this richer task model, as they fail to take into account contextual dependencies and different user behaviors. This paper presents a novel simulation-based methodology for evaluating answers to question series that addresses some of these shortcomings. Using this methodology, we examine two different behavior models: a “QA-styled” user and an “IR-styled” user. Results suggest that an off-the-shelf document retrieval system is competitive with state-of-the-art QA systems in this task. Advantages and limitations of evaluations based on user simulations are also discussed.
Keywords: Evaluation; Question answering; User simulations

Using annotations from controlled vocabularies to find meaningful associations - Lee,W. J; Raschid, Louiqa; Srinivasan,P.; Shah,N.; Rubin,D.; Noy,N. (Proceedings of the 4th international conference on Data integration in the life sciences, 2007)

Variola virus topoisomerase: DNA cleavage specificity and distribution of sites in Poxvirus genomes - Minkah,Nana; Hwang,Young; Perry,Kay; Van Duyne,Gregory D.; Hendrickson,Robert; Lefkowitz,Elliot J.; Hannenhalli, Sridhar; Bushman,Frederic D. (Virology, 2007)
Topoisomerase enzymes regulate superhelical tension in DNA resulting from transcription, replication, repair, and other molecular transactions. Poxviruses encode an unusual type IB topoisomerase that acts only at conserved DNA sequences containing the core pentanucleotide 5'-(T/C)CCTT-3'. In X-ray structures of the variola virus topoisomerase bound to DNA, protein-DNA contacts were found to extend beyond the core pentanucleotide, indicating that the full recognition site has not yet been fully defined in functional studies. Here we report quantitation of DNA cleavage rates for an optimized 13 bp site and for all possible single base substitutions (40 total sites), with the goals of understanding the molecular mechanism of recognition and mapping topoisomerase sites in poxvirus genome sequences. The data allow a precise definition of enzyme-DNA interactions and the energetic contributions of each. We then used the resulting "action matrix" to show that favorable topoisomerase sites are distributed all along the length of poxvirus DNA sequences, consistent with a requirement for local release of superhelical tension in constrained topological domains. In orthopox genomes, an additional central cluster of sites was also evident. A negative correlation of predicted topoisomerase sites was seen relative to early terminators, but no correlation was seen with early or late promoters. These data define the full variola virus topoisomerase recognition site and provide a new window on topoisomerase function in vivo.
Keywords: Annotation of topoisomerase sites; Sequence specific recognition; Topoisomerase IB; Variola virus

VAST 2007 Contest - Blue Iguanodon - Grinstein,G.; Plaisant, Catherine; Laskowski,S.; O'Connell,T.; Scholtz,J.; Whiting,M. (Visual Analytics Science and Technology, 2007. VAST 2007. IEEE Symposium on, 2007)
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 second visual analytics science and technology (VAST) contest was held in conjunction with the 2007 IEEE VAST symposium. In this contest participants were to use visual analytic tools to explore a large heterogeneous data collection to construct a scenario and find evidence buried in the data of illegal and terrorist activities that were occurring. A synthetic data set was made available as well as tasks. In this paper we describe some of the advances we have made from the first competition held in 2006.
Keywords: activities; large; activities; visual; analytic; collection; terrorist; data; heterogeneous; illegal; interfaces; tools; data; user; visualisation; graphical

Vision Geometry XV - Latecki,L.J.; Mount, Dave; Wu,A. Y (Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 2007)

Algorithms for on-line monitoring of components in an optical tweezers-based assembly cell - Peng,T.; Balijepalli,A.; Gupta,S.K.; LeBrun,T. W. (2006)
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.

ANew Algorithm for Detecting Text Line in Handwritten Documents - Li,Yi; Yefeng Zheng; David Doermann; Jaeger,Stefan (10th International Workshop on Frontiers in Handwriting Recognition, 2006)
Curvilinear text line detection and segmentation in handwritten documents is a significant challenge for handwriting recognition. Given no prior knowledge of script, we model text line detection as an image segmentation problem by enhancing text line structure using a Gaussian window, and adopting the level set method to evolve text line boundaries. Experiments show that the proposed method achieves high accuracy for detecting text lines in both handwritten and machine printed documents with many scripts.

Annotation compatibility working group report - Meyers,A.; Fang,A. C.; Ferro,L.; Kübler,S.; Jia-Lin,T.; Palmer,M.; Poesio,M.; Dolbey,A.; Schuler,K. K.; Loper,E.; Zinsmeister,H.; Penn,G.; et al. (Proceedings of the Workshop on Frontiers in Linguistically Annotated Corpora 2006, 2006)
This report explores the question of compatibility between annotation projects including translating annotation formalisms to each other or to common forms. Compatibility issues are crucial for systems that use the results of multiple annotation projects. We hope that this report will begin a concerted effort in the field to track the compatibility of annotation schemes for part of speech tagging, time annotation, treebanking, role labeling and other phenomena.

An architecture for adaptive intrusion-tolerant applications - Pal,Partha; Rubel,Paul; Atighetchi,Michael; Webber,Franklin; Sanders,William H.; Seri,Mouna; Ramasamy,HariGovind; Lyons,James; Courtney,Tod; Agbaria,Adnan; Michel Cukier; Gossett,Jeanna; et al. (Software: Practice and Experience, 2006)
Applications that are part of a mission-critical information system need to maintain a usable level of key services through ongoing cyber-attacks. In addition to the well-publicized denial of service (DoS) attacks, these networked and distributed applications are increasingly threatened by sophisticated attacks that attempt to corrupt system components and violate service integrity. While various approaches have been explored to deal with DoS attacks, corruption-inducing attacks remain largely unaddressed. We have developed a collection of mechanisms based on redundancy, Byzantine fault tolerance, and adaptive middleware that help distributed, object-based applications tolerate corruption-inducing attacks. In this paper, we present the ITUA architecture, which integrates these mechanisms in a framework for auto-adaptive intrusion-tolerant systems, and we describe our experience in using the technology to defend a critical application that is part of a larger avionics system as an example. We also motivate the adaptive responses that are key to intrusion tolerance, and explain the use of the ITUA architecture to support them in an architectural framework. Copyright © 2006 John Wiley & Sons, Ltd.
Keywords: adaptive defense; adaptive middleware; Byzantine fault tolerance; intrusion tolerance; redundancy; survivability architecture

Bootstrapping free-space optical networks - Liu,F.; Vishkin, Uzi; Milner,S. (Selected Areas in Communications, IEEE Journal on, 2006)
We introduce a challenging problem in establishing and initially configuring or bootstrapping a Free Space Optical (FSO) network. In such networks, it is assumed that each communication node is a base station, including a router and wireless optical communications hardware, and its number of transceivers is limited. In addition, the FSO networks are characterized by narrow beam, directional links (e.g., operating at 1550 nm) and support up to Gbps data rates. The problem of initially configuring the transceivers to form a connected topology is NP-complete because of the transceiver limitation. What makes this problem even more challenging is the need to configure the transceiver in a "distributed" fashion, because a node can have only direct knowledge of its neighbors. We have developed a fully distributed approximation algorithm, which constructs a spanning tree with maximal node degree at most one larger than that in the optimal solution. Due to its distributed nature, this algorithm outperforms known serial algorithms. For a graph with 200 nodes generated in some randomized model, speed-ups greater than 6 have been demonstrated.
Keywords: algorithm; free-space; algorithms; optical; approximation; communication; telecommunication; communications; configuration; randomized; FSO; base; hardware; distributed; model; spanning; network; network; network; node; connected; optical; router; optical; routing; telecommunication; searching; station; bootstrapping; communication; topology; distributed; topology; transceivers; tree; transceiver; tree; wireless

A bootstrapping model for directional wireless networks - Milner,S.; Llorca,J.; Anibha,A.; Vishkin, Uzi (Communications Letters, IEEE, 2006)
Initially configuring or bootstrapping a connected topology in directional wireless networks is a challenging problem, especially when nodes only have local connectivity information and a limited number of transceivers. This paper presents a scalable bootstrapping model which integrates: 1) a distributed bottom-up algorithm that constructs a spanning tree with degree at most one larger than the optimal 2) a resource discovery algorithm for efficient dissemination of local connectivity information, and 3) synchronization protocols to guarantee the efficient emergence of overall network connectivity from local interactions. We investigate the feasibility and scalability of the proposed model. Results are presented for different network systems, with varying size and signaling data rates.
Keywords: (mathematics); algorithm; resource; algorithm; spanning; bootstrapping; bottom-up; discovery; model; directional; network; distributed; networks; trees; protocols; protocols; radio; tree; synchronization; wireless

CAM04-6: Single-Path Routing of Time-varying Traffic - Kashyap,A.; Bhattacharjee, Bobby; La,R.; Shayman,M.; Tabatabaee,V. (Global Telecommunications Conference, 2006. GLOBECOM '06. IEEE, 2006)
We consider the problem of finding a single-path intra-domain routing for time-varying traffic. We characterize the traffic variations by a finite set of traffic profiles with given non-zero fractions of occurrence. Our goal is to optimize the average performance over all of these traffic profiles. We solve the optimal multi-path version of this problem using linear programming and develop heuristic single-path solutions using randomized rounding and iterated rounding. We analyze our single-path heuristic (finding the optimal single-path routing is NP-hard), and prove that the randomized rounding algorithm has a worst case performance bound of O(log(KN)/log(log(KN))) compared to the optimal multi-path routing with a high probability, where K is the number of traffic profiles, and N the number of nodes in the network. Further, our simulations show the iterated rounding heuristics perform close to the optimal multi-path routing on a wide range of measured ISP topologies, in both the average and the worst-case. Overall, these results are extremely positive since they show that in a wide-range of practical situations, it is not necessary to deploy multi-path routing; instead, an appropriately computed single-path routing is sufficient to provide good performance.
Keywords: algorithm; linear; algorithm; time-varying; algorithms; telecommunication; bound; IP; case; complexity; iterative; intra-domain; IP; methods; linear; multipath; network; network; ISP; networks; Internet; computational; optimal; performance; problem; heuristic; profile; worst; programming; optimal; programming; probability; randomised; rounding; routing; iterated; routing; probability; randomized; routing; telecommunication; single-path; topology; NP-hard; topology; telecommunication; traffic; traffic

Camera-Based Document Image Mosaicing - Liang,Jian; DeMenthon,Daniel; David Doermann (ICPR'06, 2006)
In this paper we present an image mosaicing method for camera-captured document images. Our method is unique in not restricting the camera position, thus allowing greater flexibility than scanner-based or fixed-camera-based approaches. To accommodate for the perspective distortions introduced by varying poses, we implement a two-step image registration process that relies on accurately computing the projectivity between any two document images with an overlapping area as small as 10%. In the overlapping area, we apply a sharpness based selection process to obtain seamless blending across the border and within. Experiments show that our approach can produce a very sharp, high resolution and accurate full page mosaic from small image patches of a document.

Component Forensics of Digital Cameras: A Non-Intrusive Approach - Swaminathan,A.; Wu,M.; Liu,K. J.R (Information Sciences and Systems, 2006 40th Annual Conference on, 2006)
This paper considers the problem of component forensics and proposes a methodology to identify the algorithms and parameters employed by various processing modules inside a digital camera. The proposed analysis techniques are non-intrusive, using only sample output images collected from the camera to find the color filter array pattern; and the algorithm and parameters of color interpolation employed in cameras. As demonstrated by various case studies in the paper, the features obtained from component forensic analysis provide useful evidence for such applications as detecting technology infringement, protecting intellectual property rights, determining camera source, and identifying image tampering.
Keywords: analysis; image; approach; processing; array; camera; image; Color; colour; detection; optical; filter; filters; forensics; detecting; identification; intellectual; infringement; digital; interpolation; component; intrusive; module; cameras; image; pattern; color; property; protection; non; right; sensors; interpolation; object; tampering; technology

Computing and displaying intermolecular negative volume for docking - Lee,C.; Varshney, Amitabh (Scientific visualization: the visual extraction of knowledge from data, 2006)
Protein docking is a Grand Challenge problem that is crucial to our understanding of biochemical processes. Several protein docking algorithms use shape complementarity as the primary criterion for evaluating the docking candidates. The intermolecular volume and area between docked molecules is useful as a measure of the shape complementarity. In this paper we discuss an algorithm for interactively computing intermolecular negative volume and the area of docking site using graphics hardware. We also present the design considerations for building an interactive 3D visualization tool for visualizing intermolecular negative volumes.

Constructing task visibility intervals for video surveillance - Lim,S.N.; Davis, Larry S.; Mittal,A. (Multimedia systems, 2006)
Vision systems are increasingly being deployed to perform complex surveillance tasks. While improved algorithms are being developed to perform these tasks, it is also important that data suitable for these algorithms be acquired – a non-trivial task in a dynamic and crowded scene viewed by multiple PTZ cameras. In this paper, we describe a real-time multi-camera system that collects images and videos of moving objects in such scenes, subject to task constraints. The system constructs “task visibility intervals” that contain information about what can be sensed in future time intervals. Constructing these intervals requires prediction of future object motion and consideration of several factors such as object occlusion and camera control parameters. Such intervals can also be combined to form multi-task intervals, during which a single camera can collect videos suitable for multiple tasks simultaneously. Experimental results are provided to illustrate the system capabilities in constructing such task visibility intervals, followed by scheduling them using a greedy algorithm.

Cooperative peer groups in NICE - Sherwood,Rob; Lee,Seungjoon; Bhattacharjee, Bobby (Computer Networks, 2006)
We present a distributed scheme for trust inference in peer-to-peer networks. Our work is in the context of the NICE system, which is a platform for implementing cooperative applications over the Internet. We describe a technique for efficiently storing user reputation information in a completely decentralized manner, and show how this information can be used to efficiently identify non-cooperative users in NICE. We present a simulation-based study of our algorithms, in which we show our scheme scales to thousands of users using modest amounts of storage, processing, and bandwidth at any individual node. Lastly we show that our scheme is robust and can form cooperative groups in systems where the vast majority of users are malicious.
Keywords: distributed algorithms; P2P; Reputation base trust

Data redistribution and remote method invocation for coupled components - Bertrand,Felipe; Bramley,Randall; Bernholdt,David E.; Kohl,James A.; Sussman, Alan; Larson,Jay W.; Damevski,Kostadin B. (Journal of Parallel and Distributed Computing, 2006)
With the increasing availability of high-performance massively parallel computer systems, the prevalence of sophisticated scientific simulation has grown rapidly. The complexity of the scientific models being simulated has also evolved, leading to a variety of coupled multi-physics simulation codes. Such cooperating parallel programs require fundamentally new interaction capabilities, to efficiently exchange parallel data structures and collectively invoke methods across programs. So-called “ M × N ” research, as part of the common component architecture (CCA) effort, addresses these special and challenging needs, to provide generalized interfaces and tools that support flexible parallel data redistribution and parallel remote method invocation. Using this technology, distinct simulation codes with disparate distributed data decompositions can work together to achieve greater scientific discoveries.
Keywords: Common component architecture; Model coupling; Parallel data redistribution; Parallel remote method invocation

D-Dupe: An Interactive Tool for Entity Resolution in Social Networks - Bilgic,M.; Licamele,L.; Getoor, Lise; Shneiderman, Ben (Visual Analytics Science And Technology, 2006 IEEE Symposium On, 2006)
Visualizing and analyzing social networks is a challenging problem that has been receiving growing attention. An important first step, before analysis can begin, is ensuring that the data is accurate. A common data quality problem is that the data may inadvertently contain several distinct references to the same underlying entity; the process of reconciling these references is called entity-resolution. D-Dupe is an interactive tool that combines data mining algorithms for entity resolution with a task-specific network visualization. Users cope with complexity of cleaning large networks by focusing on a small subnetwork containing a potential duplicate pair. The subnetwork highlights relationships in the social network, making the common relationships easy to visually identify. D-Dupe users resolve ambiguities either by merging nodes or by marking them distinct. The entity resolution process is iterative: as pairs of nodes are resolved, additional duplicates may be revealed; therefore, resolution decisions are often chained together. We give examples of how users can flexibly apply sequences of actions to produce a high quality entity resolution result. We illustrate and evaluate the benefits of D-Dupe on three bibliographic collections. Two of the datasets had already been cleaned, and therefore should not have contained duplicates; despite this fact, many duplicates were rapidly identified using D-Dupe's unique combination of entity resolution algorithms within a task-specific visual interface
Keywords: algorithm; data; analysis; social; computing; user; D-Dupe; interactive; interface; data; interfaces; mining; mining; interactive; network; problem; entity; QUALITY; resolution; entity-resolution; social; sciences; systems; social; tool; data; visual; visualization; task-specific

Decentralized message ordering for publish/subscribe systems - Lumezanu,Cristian; Spring, Neil; Bhattacharjee, Bobby (Proceedings of the ACM/IFIP/USENIX 2006 International Conference on Middleware, 2006)
We describe a method to order messages across groups in a publish/subscribe system without centralized control or large vector timestamps. We show that our scheme is practical---little state is required; that it is scalable---the maximum message load is limited by receivers; and that it performs well---the paths messages traverse to be ordered are not made much longer than necessary. Our insight is that only messages to groups that overlap in membership can be observed to arrive out of order: sequencing messages to these groups is sufficient to provide a consistent order, and when publishers subscribe to the groups to which they send, this message order is a causal order.

Detecting Text Line in Handwritten Documents - Li,Yi; Yefeng Zheng; David Doermann (ICPR'06, 2006)
Although detecting text lines in machine printed documents is typically considered as a solved problem, it is still a challenge to segment handwritten text lines in the general sense given no prior knowledge of scrip. This paper models text line detection as an image segmentation problem by enhancing text line structure using a Gaussian window, and adopting the level set method to evolve text line boundaries. Experiments show that the method, which is script independent, achieves high accuracy for detecting text lines in both handwritten and machine printed documents.

EIGENTEST: A Test Matrix Generator for Large-Scale Eigenproblems - Lee,Che Rung; Stewart, G.W. (Instititue for Advanced Computer Studies, Univ of Maryland, College Park, 2006)
Eigentest is a package that produces real test matrices with knowneigensystems. 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)'*b, inv(A - sI)*b, and inv(A - sI)*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 paper introduces the eigenmat and describes implementations in Fortran~77, Fortran~95, C, and Matlab.
Keywords: Technical Report

Evolution of non-LTR retrotransposons in the trypanosomatid genomes: Leishmania major has lost the active elements - Bringaud,Frédéric; Ghedin,Elodie; Blandin,Gaëlle; Bartholomeu,Daniella C.; Caler,Elisabet; Levin,Mariano J.; Baltz,Théo; El‐Sayed, Najib M. (Molecular and Biochemical Parasitology, 2006)
The ingi and L1Tc non-LTR retrotransposons - which constitute the ingi clade - are abundant in the genome of the trypanosomatid species Trypanosoma brucei and Trypanosoma cruzi, respectively. The corresponding retroelements, however, are not present in the genome of a closely related trypanosomatid, Leishmania major. To study the evolution of non-LTR retrotransposons in trypanosomatids, we have analyzed all ingi/L1Tc elements and highly degenerate ingi/L1Tc-related sequences identified in the recently completed T. brucei, T. cruzi and L. major genomes. The coding sequences of 242 degenerate ingi/L1Tc-related elements (DIREs) in all three genomes were reconstituted by removing the numerous frame shifts. Three independent phylogenetic analyses conducted on the conserved domains encoded by these elements show that all DIREs, including the 52 L. major DIREs, form a monophyletic group belonging to the ingi clade. This indicates that the trypanosomatid ancestor contained active mobile elements that have been retained in the Trypanosoma species, but were lost from L. major genome, where only remnants (DIRE) are detectable. All 242 DIREs analyzed group together according to their species origin with the exception of 11 T. cruzi DIREs which are close to the T. brucei ingi/DIRE families. Considering the absence of known horizontal transfer between the African T. brucei and the South-American T. cruzi, this suggests that this group of elements evolved at a lower rate when compared to the other trypanosomatid elements. Interestingly, the only nucleotide sequence conserved between ingi and L1Tc (the first 79 residues) is also present at the 5'-extremity of all the full length DIREs and suggests a possible role for this conserved motif, as well as for DIREs.
Keywords: Degenerate retroelement; Evolution; Ingi; L1Tc; Leishmania major; Non-LTR retrotransposon; Retroposon; Trypanosoma brucei; Trypanosoma cruzi

Exploring content-actor paired network data using iterative query refinement with NetLens - Lee,Bongshin; Kang,Hyunmo; Plaisant, Catherine; Bederson, Benjamin B. (Digital Libraries, 2006. JCDL '06. Proceedings of the 6th ACM/IEEE-CS Joint Conference on, 2006)
Networks have remained a challenge for information retrieval and visualization because of the rich set of tasks that users want to accomplish. This paper demonstrates a tool, NetLens, to explore a content-actor paired network data model. The NetLens interface was designed to allow users to pose a series of elementary queries and iteratively refine visual overviews and sorted lists. This enables the support of complex queries that are traditionally hard to specify in node-link visualizations. NetLens is general and scalable in that it applies to any dataset that can be represented with our abstract content-actor data model
Keywords: data; interface; libraries; query; management; model; data; models; data; NetLens; content-actor; network; pair; processing; user; query; refinement; data; retrieval; iterative; systems; visualisation; digital; visualization; information

Exploring erotics in Emily Dickinson's correspondence with text mining and visual interfaces - Plaisant, Catherine; Rose,James; Yu,Bei; Auvil,Loretta; Kirschenbaum,Matthew G.; Smith,Martha Nell; Clement,Tanya; Lord,Greg (Proceedings of the 6th ACM/IEEE-CS joint conference on Digital libraries, 2006)
This paper describes a system to support humanities scholars in their interpretation of literary work. It presents a user interface and web architecture that integrates text mining, a graphical user interface and visualization, while attempting to remain easy to use by non specialists. Users can interactively read and rate documents found in a digital libraries collection, prepare training sets, review results of classification algorithms and explore possible indicators and explanations. Initial evaluation steps suggest that there is a rationale for "provocational" text mining in literary interpretation.
Keywords: case studies; humanities; literary criticism; text mining; user interface; Visualization

Exploring the limits of single-iteration clarification dialogs - Jimmy Lin; Wu,Philip; Demner-Fushman,Dina; Abels,Eileen (Proceedings of the 29th annual international ACM SIGIR conference on Research and development in information retrieval, 2006)
Single-iteration clarification dialogs, as implemented in the TREC HARD track, represent an attempt to introduce interaction into ad hoc retrieval, while preserving the many benefits of large-scale evaluations. Although previous experiments have not conclusively demonstrated performance gains resulting from such interactions, it is unclear whether these findings speak to the nature of clarification dialogs, or simply the limitations of current systems. To probe the limits of such interactions, we employed a human intermediary to formulate clarification questions and exploit user responses. In addition to establishing a plausible upper bound on performance, we were also able to induce an "ontology of clarifications" to characterize human behavior. This ontology, in turn, serves as the input to a regression model that attempts to determine which types of clarification questions are most helpful. Our work can serve to inform the design of interactive systems that initiate user dialogs.
Keywords: interactive retrieval; intermediated search; TREC HARD

Eye of the Beholder: Phone-Based Text-Recognition for the Visually-Impaired - Tudor Dumitras; Lee, M.; Quinones, P.; Smailagic, A.; Siewiorek, Dan; Narasimhan, P. (2006 10th IEEE International Symposium on Wearable Computers, 2006)
Blind and visually-impaired people cannot access essential information in the form of written text in our environment (e.g., on restaurant menus, street signs, door labels, product names and instructions, expiration dates). In this paper, we present and evaluate a mobile text-recognition system capable of extracting written information from a wide variety of sources and communicating it on-demand to the user. The user needs no additional hardware except an ordinary, Internet- enabled mobile camera-phone - a device that many visually-impaired individuals already own. This approach fills a gap in assistive technologies for the visually- impaired because it makes users aware of textual information not available to them through any other means.
Keywords: CAMERAS; data mining; handicapped aids; Hardware; Image quality; Internet; Land mobile radio cellular systems; Mobile computing; mobile handsets; mobile text-recognition system; Optical character recognition software; phone-based text-recognition; Product safety; Text recognition; visually-impaired

Fair file swarming with FOX - Levin,D.; Sherwood,R.; Bhattacharjee, Bobby (Proc. 5th IPTPS, 2006)
File swarming is a popular method of coordi-nated download by which peers obtain a file from an under- provisioned server. Critical problems arise within this domain when users act selfishly, yet most systems are built with altru- ism assumed. Working under the assumption that all peers are greedy, we introduce the Fair, Optimal eXchange (FOX) protocol. FOX, in addition to effective and robust application of the tit-for-tat incentive mechanism, provides theoretically optimal download times when everyone cooperates. Under our assumption of server and peer capabilities, we develop a strong threat model that provides peers with the incentives to not deviate from the protocol. From a theoretical perspective, we prove FOX’s optimality and incentive properties, even when the network consists only of purely self-interested peers. We also discuss issues in implementing and deploying such a system, and address the cost of ensuring fairness in a domain where efficiency is so important.

First Steps Toward an Electronic Field Guide for Plants - Haibin,Gaurav Agarwal; Agarwal,Gaurav; Ling,Haibin; Jacobs, David W.; Shirdhonkar,Sameer; Kress,W. John; Russell,Rusty; Belhumeur,Peter; Dixit,An; Feiner,Steve; Mahajan,Dhruv; Sunkavalli,Kalyan; et al. (Taxon, 2006)
this paper, we will describe our progress towards building a digital collection of the Smithsonian's type specimens, developing recognition algorithms that can match an image of a leaf to the species of plant from which it comes, and designing user interfaces for interacting with an electronic field guide. To start, we are developing a prototype electronic field guide for the flora of Plummers Island, a small, well-studied island in the Potomac River. This prototype system contains multiple images for each of about 130 species of plants on the island, and should soon grow to cover all 200+ species currently recorded (Shetler et al., 2005). Images of full specimens are available, as well as images of isolated leaves of each species. A zoomable user interface allows a user to browse these images, zooming in on ones of interest. Visual recognition algorithms assist a botanist in locating the specimens that are most relevant to identify the species of a plant. The system currently runs on a small hand-held computer. We will describe the components of this prototype, and also describe some of the future challenges we anticipate if we are to provide botanists in the field with all the resources that are now currently available in the world's museums and herbaria. Type Specimen Digital Collection The first challenge in producing our electronic field guide is to create a digital collection covering all of the Smithsonian's 85,000 vascular plant type specimens. For each type specimen, the database should eventually include systematically acquired high-resolution digital images of the specimen, textual descriptions, links to decision trees, images of live plants, and 3D models. Figure 1: On the left, our set-up at the Smithsonian for digitally photographing type specimens. On the...

A flexible system framework for a nanoassembly cell using optical tweezers - Balijepalli,A.; LeBrun,T. W.; Gupta,S.K. (2006)
The optical tweezers instrument is a unique tool fordirected assembly of nanocomponents. In order to function as a viable nanomanufacturing tool, a software architecture is needed to run the optical tweezers hardware, provide an effective user interface, and allow automated operation. A flexible software system framework is described to utilize the optical tweezers hardware to its full potential. Initially we lay out the requirements for the system framework and define the broad architectural choices made while implementing the different modules. Implementation details of key system modules are then described. The flexible nature of the architecture is demonstrated by showing how a simulation module can be seamlessly included into the framework to replace the optical tweezers hardware as necessary. Finally, we show some representative assembly operations to demonstrate the capabilities of the system.

Geometry-dependent lighting - Lee,C. H; Hao,X.; Varshney, Amitabh (Visualization and Computer Graphics, IEEE Transactions on, 2006)
In this paper, we introduce geometry-dependent lighting that allows lighting parameters to be defined independently and possibly discrepantly over an object or scene based on the local geometry. We present and discuss light collages, a lighting design system with geometry-dependent lights for effective feature-enhanced visualization. Our algorithm segments the objects into local surface patches and places lights that are locally consistent but globally discrepant to enhance the perception of shape. We use spherical harmonics for efficiently storing and computing light placement and assignment. We also outline a method to find the minimal number of light sources sufficient to illuminate an object well with our globally discrepant lighting approach.
Keywords: Computer-Assisted; Imaging; feature-enhanced visualization; geometry-dependent light; light collage; light placement; lighting design system; computational geometry; data visualisation; lighting; Algorithms; Computer Graphics; Image Enhancement; Image Interpretation; Three-Dimensional; Information Storage and Retrieval; Lighting; User-Computer Interface

Headphone-Based Reproduction of 3D Auditory Scenes Captured by Spherical/Hemispherical Microphone Arrays - Zhiyun Li; Duraiswami, Ramani (Acoustics, Speech and Signal Processing, 2006. ICASSP 2006 Proceedings. 2006 IEEE International Conference on, 2006)
We propose a method to reproduce 3D auditory scenes captured by spherical microphone arrays over headphones. This algorithm employs expansions of the captured sound and the head related transfer function over the sphere and uses the orthonormality of the spherical harmonics. Using a spherical microphone array, we first record the 3D auditory scene, then the recordings are spatially filtered and reproduced through headphones in the orthogonal beam-space of the head related transfer functions (HRTFs). We use the KEMAR HRTF measurements to verify our algorithm
Keywords: 3D; analysis; headphones; microphone; arrays; orthogonal; arrays; spatial; auditory; beam-space; spatial; filter; spherical; filters; function; headphone-based; harmonics; array; microphone; processing; audio; processing; harmonic; related; reproduction; hemispherical; scenes; head; signal; transfer

High-confidence medical device software and systems - Lee,I.; Pappas,G. J; Cleaveland, Rance; Hatcliff,J.; Krogh,B. H; Lee,P.; Rubin,H.; Sha,L. (Computer, 2006)
Given the shortage of caregivers and the increase in an aging US population, the future of US healthcare quality does not look promising and definitely is unlikely to be cheaper. Advances in health information systems and healthcare technology offer a tremendous opportunity for improving the quality of care while reducing costs. The development and production of medical device software and systems is a crucial issue, both for the US economy and for ensuring safe advances in healthcare delivery. As devices become increasingly smaller in physical terms but larger in software terms, the design, testing, and eventual Food and Drug Administration (FDA) device approval is becoming much more expensive for medical device manufacturers both in terms of time and cost. Furthermore, the number of devices that have recently been recalled due to software and hardware problems is increasing at an alarming rate. As medical devices are becoming increasingly networked, ensuring even the same level of health safety seems a challenge.
Keywords: Aging; biomedical equipment; Clinical software engineering; Costs; FDA device; Food and Drug Administration device; health and safety; health care; health information system; health safety; healthcare delivery; Healthcare technology; Information systems; medical computing; medical device manufacturing; medical device software development; medical device systems development; medical information systems; Medical services; Medical software; Medical tests; networked medical devices; Production systems; Software design; Software safety; Software systems; Software testing; US healthcare quality

Identification and cross-species comparison of canine osteoarthritic gene regulatory cis-elements - Hannenhalli, Sridhar; Middleton,R.P.; Levy,S.; Perroud,B.; Holzwarth,J.A.; McDonald,K.; Hannah,S.S. (Osteoarthritis and Cartilage, 2006)
SummaryObjectiveTo better understand transcription regulation of osteoarthritis (OA) by examining common promoter motifs in canine osteoarthritic genes, to identify other genes containing these motifs and to assess the conservation of these motifs between canine, human, mouse and rat. Design Differentially expressed transcripts in canine OA were mapped to the human genome. We thus identified 20 orthologous human transcripts representing 19 up-regulated genes and 62 orthologous transcripts representing 60 down-regulated genes. The 5 kbp upstream regions of these transcripts were used to identify binding sites and build promoter models based on those sites. The human genome was subsequently searched for other transcripts likely to be regulated by the same promoter models. Orthologous transcripts were then identified in canine, rat and mouse for determination of potential cross-species conservation of binding sites comprising the promoter model. Results Four promoter models containing 5–6 transcripts and 5–8 common transcription factor binding sites were developed. They include binding sites for AP-4, AP-2α and γ, and E2F. Several hundred other human genes were found to contain these promoter motifs. Furthermore these motifs were significantly over represented in the orthologous genes in canine, rat and mouse genomes. Conclusions We have developed and applied a computational methodology to identify common promoter elements implicated in OA and shared amongst four higher vertebrates. The transcription factors associated with these binding sites and other genes driven by these promoter motifs have been implicated in OA, chondrocyte development and with other biological factors involved in the disease.
Keywords: Chondrocyte; Gene expression; Osteoarthritis; Promoter

Image fusion using cokriging - Memarsadeghi,N.; Le Moigne,J.; Mount, Dave (Geosci. and Remote Sens. Symp., 2006. IGARSS 2006. IEEE Int. Conf. on, 2006)

Image Registration and Fusion Studies for the Integration of Multiple Remote Sensing Data - Le Moigne,J.; Cole-Rhodes,A.; Eastman,R.; Jain,P.; Joshua,A.; Memarsadeghi,N.; Mount, Dave; Netanyahu,N.; Morisette,J.; Uko-Ozoro,E. (Acoustics, Speech and Signal Processing, 2006. ICASSP 2006 Proceedings. 2006 IEEE International Conference on, 2006)
The future of remote sensing will see the development of spacecraft formations, and with this development will come a number of complex challenges such as maintaining precise relative position and specified attitudes. At the same time, there will be increasing needs to understand planetary system processes and build accurate prediction models. One essential technology to accomplish these goals is the integration of multiple source data. For this integration, image registration and fusion represent the first steps and need to be performed with very high accuracy. In this paper, we describe studies performed in both image registration and fusion, including a modular framework that was built to describe registration algorithms, a Web-based image registration toolbox, and the comparison of several image fusion techniques using data from the EO-1/ALI and Hyperion sensors
Keywords: ALI; EO-1; fusion studies; geophysical signal processing; Hyperion sensors; image registration; Internet; multiple remote sensing data; multiple source data; Remote sensing; Web-based image registration toolbox

Image Tampering Identification using Blind Deconvolution - Swaminathan,A.; M. Wu; Liu,K. J.R (Image Processing, 2006 IEEE International Conference on, 2006)
Digital images have been used in growing number of applications from law enforcement and surveillance, to medical diagnosis and consumer photography. With such widespread popularity and the presence of low-cost image editing softwares, the integrity of image content can no longer be taken for granted. In this paper, we propose a novel technique based on blind deconvolution to verify image authenticity. We consider the direct output images of a camera as authentic, and introduce algorithms to detect further processing such as tampering applied to the image. Our proposed method is based on the observation that many tampering operations can be approximated as a combination of linear and non-linear components. We model the linear part of the tampering process as a filter, and obtain its coefficients using blind deconvolution. These estimated coefficients are then used to identify possible manipulations. We demonstrate the effectiveness of the proposed image authentication technique and compare our results with existing works
Keywords: (access; approximation; blind; authentication; image; coding; compression; deconvolution; filtering; control); data; deconvolution; camera; consumer; diagnosis; surveillance; tampering; editing; identification; approximation; images; filter; photography; digital; process; image; softwares; medical; theory; biometrics; theory; image

Imaging as an Alternative Data Channel for Camera Phones - Liu,Xu; Huiping Li; David Doermann (ACM International Conference Proceeding Series; Proceedings of the 5th International Conference on Mobile and Ubiquitous Multimedia, 2006)
In this paper, we demonstrate a solution to use cameras to download data to cell phones as an alternative to existing wireless (CDMA/GPRS, BlueTooth), infrared or cable connections. In our method the data is encoded as a sequence of images, which can be displayed on any flat display, captured by users with their camera phones, and decoded by pre-embedded software. To solve this problem we need to be able to (1) encode arbitrary data as a sequence of images, (2) process captured images under various lighting variations and perspective distortions while maintaining real-time performance, and (3) decode the processed images robustly even when partial data is lost. In the paper we address these challenges in detail and present our solution. We have implemented a prototype which allows users to successfully download various types of files, including pictures, ring tones and Java programs to the camera phones. We discuss the limitations of our solution, and future works to overcome these limitations.

Implementing a bioinformatics pipeline (bip) on a mediator platform: Comparing cost and quality of alternate choices - Eckman,B. A; Gaasterland,T.; Lacroix,Z.; Raschid, Louiqa; Snyder,B.; Vidal,M. E (Data Engineering Workshops, 2006. Proceedings. 22nd International Conference on, 2006)

Improved lower and upper bounds for universal TSP in planar metrics - Hajiaghayi, Mohammad T.; Kleinberg,R.; Leighton,T. (Proceedings of the seventeenth annual ACM-SIAM symposium on Discrete algorithm, 2006)

JET: dynamic join-exit-tree amortization and scheduling for contributory key management - Mao,Yinian; Sun,Yan; M. Wu; Liu,K. J.R (IEEE/ACM Trans. Netw., 2006)
In secure group communications, the time cost associated with key updates in the events of member join and departure is an important aspect of quality of service, especially in large groups with highly dynamic membership. To achieve better time efficiency, we propose a join-exit-tree (JET) key management framework. First, a special key tree topology with join and exit subtrees is introduced to handle key updates for dynamic membership. Then, optimization techniques are employed to determine the capacities of join and exit subtrees for achieving the best time efficiency, and algorithms are designed to dynamically update the join and exit trees. We show that, on average, the asymptotic time cost for each member join/departure event is reduced to O(log (log n)) from the previous cost of O(log n), where n is the group size. Our experimental results based on simulated user activities as well as the real MBone data demonstrate that the proposed JET scheme can significantly improve the time efficiency, while maintaining low communication and computation cost, of tree-based contributory key management.
Keywords: contributory key management; dynamic tree topology; secure group communications; time efficiency

Leveraging recurrent phrase structure in large-scale ontology translation - Murray,G. C; Dorr, Bonnie J; Jimmy Lin; Hajič,J.; Pecina,P. (Proceedings of the 11th Annual Conference of the European Association for Machine Translation, 2006)
This paper presents a process for leveraging structural relationships and reusablephrases when translating large-scale ontologies. Digital libraries are becoming more and more prevalent. An important step in providing universal access to such material is to pro- vide multi-lingual access to the underlying principles of organization via ontologies, thesauri, and controlled vocabularies. Machine translation of these resources requires high accuracy and a deep vocabulary. Human input is often required, but full manual translation can be slow and expensive. We report on a cost-effective approach to ontology translation. We describe our technique of prioritization, our process of collecting aligned translations and generating a new lexicon, and the resulting improvement to translation system output. Our preliminary evaluation indicates that this technique provides significant cost savings for human-assisted translation. The process we developed can be applied to ontologies in other domains and is easily incorporated into other translation systems.

Leveraging reusability: cost-effective lexical acquisition for large-scale ontology translation - Murray,G. Craig; Dorr, Bonnie J; Jimmy Lin; Hajič,Jan; Pecina,Pavel (Proceedings of the 21st International Conference on Computational Linguistics and the 44th annual meeting of the Association for Computational Linguistics, 2006)
Thesauri and ontologies provide important value in facilitating access to digital archives by representing 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 ontologies precludes fully-automated machine translation using general-domain lexical resources. In this paper, we present an efficient process for leveraging human translations when constructing domain-specific lexical resources. We evaluate the effectiveness of this process by producing a probabilistic phrase dictionary and translating a thesaurus of 56,000 concepts used to catalogue a large archive of oral histories. Our experiments demonstrate a cost-effective technique for accurate machine translation of large ontologies.

Machine Translation: Interlingual Methods - Dorr, Bonnie J; Hovy,E.; Levin,L. (Encyclopedia of Language & Linguistics (Second Edition)Encyclopedia of Language & Linguistics (Second Edition), 2006)
An interlingua is a notation for representing the content of a text that abstracts away from the characteristics of the language itself and focuses on the meaning (semantics) alone. Interlinguas are typically used as pivot representations in machine translation, allowing the contents of a source text to be generated in many different target languages. Because of the complexities involved, few interlinguas are more than demonstration prototypes, and only one has been used in a commercial MT system. In this article, we define the components of an interlingua and the principal issues faced by designers and builders of interlinguas and interlingua MT systems, illustrating with examples from operational systems and research prototypes. We discuss current efforts to annotate texts with interlingua-based information.
Keywords: approximate interlingua; compositionality; conceptual knowledge; cross-language divergences; interlingua; interlingual speech translation; language-independent representation; lexical-conceptual structure; Machine translation; ontology; predicate-argument structure; semantic annotation; semantic frames; semantic zones; text-meaning representations; THEMATIC ROLES

Making a difference: integrating socially relevant projects into HCI teaching - Shneiderman, Ben; Bishop,Ann; Friedman,Batya; Lazar,Jonathan; Marsden,Gary; Nass,Cliff (CHI '06 extended abstracts on Human factors in computing systems, 2006)
Enriching courses on human-computer interaction with socially-relevant projects provides a compelling opportunity for students to improve their education and make socially beneficial contributions. By having clearly defined user communities outside the classroom, students have the chance to practice their interview, observation, and usability testing skills, while developing projects that continue beyond the semester. These projects often give students life-changing exposure to genuine needs and impressive results to include in their portfolio when seeking employment. Educators will present their strategies for arranging, supervising, and grading these projects. Students will describe their experience and how it influenced them.
Keywords: education; making a difference; relevance; service learning; social impact; team projects

Measurement-based optimal routing on overlay architectures for unicast sessions - La,R.J.; Shayman,M.A.; Bhattacharjee, Bobby (Computer Networks, 2006)
We propose a measurement-based routing algorithm to load-balance intradomain traffic along multiple paths for multi-ple unicast sources. Multiple paths are established using overlay nodes. The distributed algorithm is derived from simul- taneous perturbation stochastic approximation (SPSA) and does not assume that the gradient of an analytical cost function is known. Instead, we rely on (potentially) noisy estimates from local measurements. Using the analytical model presented in the paper, we first show the almost sure convergence of the algorithm to the optimal solution under a decreas- ing step size policy (as with a standard SPSA model). Motivated by practical concerns, we next consider the constant step size case, for which we establish weak convergence. We provide simulation results to demonstrate the advantages of our proposed algorithm under various network scenarios, and also present a comparative study with MATE (an existing opti- mal routing algorithm)

Methods for automatically evaluating answers to complex questions - Jimmy Lin; Demner-Fushman,D. (Information Retrieval, 2006)
Evaluation is a major driving force in advancing the state of the art in language technologies. In particular, methods for automatically assessing the quality of machine output is the preferred method for measuring progress, provided that these metrics have been validated against human judgments. Following recent developments in the automatic evaluation of machine translation and document summarization, we present a similar approach, implemented in a measure called POURPRE, an automatic technique for evaluating answers to complex questions based on n-gram co-occurrences between machine output and a human-generated answer key. Until now, the only way to assess the correctness of answers to such questions involves manual determination of whether an information “nugget” appears in a system's response. The lack of automatic methods for scoring system output is an impediment to progress in the field, which we address with this work. Experiments with the TREC 2003, TREC 2004, and TREC 2005 QA tracks indicate that rankings produced by our metric correlate highly with official rankings, and that POURPRE outperforms direct application of existing metrics.

Models for Advancing PRAM and Other Algorithms into Parallel Programs for a PRAM-On-Chip Platform - Vishkin, Uzi; Caragea,George C.; Lee,Bryant (Technical Reports from UMIACS, UMIACS-UMIACS-TR-2006-21, 2006)
A bold vision that guided this work is as follows: (i) a parallel algorithms and programming course could become a standard course in every undergraduate computer science program, and (ii) this course could be coupled with a so-called PRAM-On-Chip architecture --- a commodity high-end multi-core computer architecture.In fact, the current paper is a tutorial on how to convert PRAM algorithms into efficient PRAM-On-Chip programs. Coupled with a text on PRAM algorithms as well as an available PRAM-On-Chip tool-chain, comprising a compiler and a simulator, the paper provides the missing link for upgrading a standard theoretical PRAM algorithms class to a parallel algorithms and programming class. Having demonstrated that such a course could cover similar programming projects and material to what is covered by a typical first serial algorithms and programming course, the paper suggests that parallel programming in the emerging multi-core era does not need to be more difficult than serial programming. If true, a powerful answer to the so-called parallel programming open problem is being provided. This open problem is currently the main stumbling block for the industry in getting the upcoming generation of multi-core architectures to improve single task completion time using easy-to-program application programmer interfaces. Known constraints of this open problem, such as backwards compatibility on serial code, are also addressed by the overall approach. More concretely, a widely used methodology for advancing parallel algorithmic thinking into parallel algorithms is revisited, and is extended into a methodology for advancing parallel algorithms to PRAM-On-Chip programs. A performance cost model for the PRAM-On-Chip is also presented. It uses as complexity metrics the length of sequence of round trips to memory (LSRTM) and queuing delay (QD) from memory access queues, in addition to standard PRAM computation costs. Highlighting the importance of LSRTM in determining performance is another contribution of the paper. Finally, some alternatives to PRAM algorithms, which, on one hand, are easier-to-think, but, on the other hand, suppress more architecture details, are also discussed.
Keywords: Technical Report

Mosaicing of Camera-captured Documents Without Pose Restriction - Liang,Jian; DeMenthon,Daniel; David Doermann (Computer Vision and Image Understanding, 2006)
In this paper we present an image mosaicing method for camera-captured documents. Our method is unique in not restricting the camera position, thus allowing greater flexibility than approaches using scanner or fixed-cameras. To accommodate for the perspective distortions introduced by varying poses, we implement a two step image registration process that accurately computes the projectivity between any two document images with an overlapping area that may be as small as 10%. In the overlapping area, we apply a sharpness based selection process to obtain seamless composition across the border and within. Experiments show that our approach can produce a very sharp, high resolution and accurate full page mosaic from small image patches of a document captured from unconstrained positions.

Motion Based Correspondence for 3D Tracking of Multiple Dim Objects - Veeraraghavan,A.; Srinivasan, M.; Chellapa, Rama; Baird, E.; Lamont, R. (Acoustics, Speech and Signal Processing, 2006. ICASSP 2006 Proceedings. 2006 IEEE International Conference on, 2006)
Tracking multiple objects in a video is a demanding task that is frequently encountered in several systems such as surveillance and motion analysis. Ability to track objects in 3D requires the use of multiple cameras. While tracking multiple objects using multiples video cameras, establishing correspondence between objects in the various cameras is a nontrivial task. Specifically, when the targets are dim or are very far away from the camera, appearance cannot be used in order to establish this correspondence. Here, we propose a technique to establish correspondence across cameras using the motion features extracted from the targets, even when the relative position of the cameras is unknown. Experimental results are provided for the problem of tracking multiple bees in natural flight using two cameras. The reconstructed 3D flight paths of the bees show some interesting flight patterns
Keywords: 3D; analysis; motion; analysis; video; based; cameras; feature; correspondence; motion; dim; extraction; image; extraction; multiple; features; MOTION; objects; video; processing; signal; tracking; motion

Multiuser cross-layer resource allocation for video transmission over wireless networks - Su,Guan-Ming; Man,Zhu; M. Wu; Liu,K. J.R (Network, IEEE, 2006)
With the advancement of video-compression technology and the wide deployment of wireless networks, there is an increasing demand for wireless video communication services, and many design challenges remain to be overcome. In this article, we discuss how to dynamically allocate resources according to the changing environments and requirements, so as to improve the overall system performance and ensure individual quality of service (QoS). Specifically, we consider two aspects with regard to design issues: cross-layer design, which jointly optimizes resource utilization from the physical layer to the application layer, and multiuser diversity, which explores source and channel heterogeneity for different users. We study how to efficiently transmit multiple video streams, encoded by current and future video codecs, over resource-limited wireless networks such as 3G/4G cellular system and future wireless local/metropolitan area networks (WLANs/WMANs)
Keywords: 3G; allocation; multiuser; allocation; video; cellular; channels; quality; codecs; video; coding; video; communication; 4G; communication; data; compression; diversity; cross-layer; diversity; physical; layer; multiple; layer; quality; mobile; networks; 3G; of; reception; multiuser; resource; service; resource; service; video; streaming; streams; multiuser; system; 4G; system; QoS; application; technology; wireless; transmission; video-compression; video

Multiuser distortion management of layered video over resource limited downlink multicode-CDMA - Han,Z.; Su,Guan-Ming; Kwasinski,A.; M. Wu; Liu,K. J.R (Wireless Communications, IEEE Transactions on, 2006)
Transmitting multiple real-time encoded videos to multiple users over wireless cellular networks is a key driving force for developing broadband technology. We propose a new framework to transmit multiple users' video programs encoded by MPEG-4 FGS codec over downlink multicode CDMA networks in real time. The proposed framework jointly manages the rate adaptation of source and channel coding, CDMA code allocation, and power control. Subject to the limited system resources, such as the number of pseudo-random codes and the maximal power for CDMA transmission, we develop an adaptive scheme of distortion management to ensure baseline video quality for each user and further reduce the overall distortion received by all users. To efficiently utilize system resources, the proposed scheme maintains a balanced ratio between the power and code usages. We also investigate three special scenarios where demand, power, or code is limited, respectively. Compared with existing methods in the literature, the proposed algorithm can reduce the overall system's distortion by 14% to 26%. In the demand-limited case and the code-limited but power-unlimited case, the proposed scheme achieves the optimal solutions. In the power-limited but code-unlimited case, the proposed scheme has a performance very close to a performance upper bound
Keywords: (mobile; access; combined; allocation; broadband; case; layered; CDMA; cellular; code; codes; radio; codes; real-time; codes; telecommunication; coding; mobility; coding; video; coding; wireless; communication; control; pseudo-random; control; pseudonoise; control; video; distortion; division; downlink; encoded; limited; links; random; management; management; power; multicode-CDMA; source-channel; multiple; networks; broadband; networks; cellular; radio); power; radio; code; source-channel; technology; code-unlimited; video; multiuser; videos; resource

New lower bounds for oblivious routing in undirected graphs - Hajiaghayi, Mohammad T.; Kleinberg,R. D; Leighton,T.; R\äcke,H. (Proceedings of the seventeenth annual ACM-SIAM symposium on Discrete algorithm, 2006)

Non-Intrusive Forensic Analysis of Visual Sensors Using Output Images - Swaminathan,A.; M. Wu; Liu,K. J.R (Acoustics, Speech and Signal Processing, 2006. ICASSP 2006 Proceedings. 2006 IEEE International Conference on, 2006)
This paper considers the problem of non-intrusive forensic analysis of the individual components in visual sensors and its implementation. As a new addition to the emerging area of forensic engineering, we present a framework for analyzing technologies employed inside digital cameras based on output images, and develop a set of forensic signal processing algorithms for visual sensors based on color array sensor and interpolation methods. We show through simulations that the proposed method is robust against compression and noise, and can help identify various processing components inside the camera. Such a non-intrusive forensic framework would provide useful evidence for analyzing technology infringement and evolution for visual sensors
Keywords: algorithms; interpolation; analysis; image; analysis; output; array; cameras; forensic; Color; colour; engineering; forensic; forensic; images; visual; methods; nonintrusive; PROCESSING; sensor; digital; sensors; cameras; image; sensors; interpolation; signal

A One-Threshold Algorithm for Detecting Abandoned Packages Under Severe Occlusions Using a Single Camera - Lim,Ser-Nam; Davis, Larry S. (Technical Reports from UMIACS, 2006)
We describe a single-camera system capable of detecting abandoned packages under severe occlusions, which leads to complications on several levels. The first arises when frames containing only background pixels are unavailable for initializing the background model - a problem for which we apply a novel discriminative measure. The proposed measure is essentially the probability of observing a particular pixel value, conditioned on the probability that no motion is detected, with the pdf on which the latter is based being estimated as a zero-mean and unimodal Gaussian distribution from observing the difference values between successive frames. We will show that such a measure is a powerful discriminant even under severe occlusions, and can deal robustly with the foreground aperture effect - a problem inherently caused by differencing successive frames. The detection of abandoned packages then follows at both the pixel and region level. At the pixel-level, an ``abandoned pixel'' is detected as a foreground pixel, at which no motion is observed. At the region-level, abandoned pixels are ascertained in a Markov Random Field (MRF), after which they are clustered. These clusters are only finally classified as abandoned packages, if they display temporal persistency in their size, shape, position and color properties, which is determined using conditional probabilities of these attributes. The algorithm is also carefully designed to avoid any thresholding, which is the pitfall of many vision systems, and which significantly improves the robustness of our system. Experimental results from real-life train station sequences demonstrate the robustness and applicability of our algorithm.
Keywords: Technical Report

Optimization of signal processing software for control system implementation - Bhattacharyya, Shuvra S.; Levine,William S. (Computer Aided Control System Design, 2006 IEEE International Conference on Control Applications, 2006 IEEE International Symposium on Intelligent Control, 2006 IEEE, 2006)
Signal processing plays a fundamental role in the design of control systems #x2014; the portion of a digitally-implemented control system between the sensor outputs and the actuator inputs is precisely a digital signal processor (DSP). Consequently, effective techniques for design and optimization of signal processing software are important in achieving efficient controller implementations. Motivated by these relationships, this paper reviews techniques for modeling signal processing functionality in a manner that exposes aspects of application structure that are useful for mapping the functionality into efficient implementations. The paper then introduces some representative techniques that operate on such models to systematically derive optimized implementations from them.

Parallel syntactic annotation of multiple languages - Rambow,O.; Dorr, Bonnie J; Farwell,D.; Green,R.; Habash,N.; Helmreich,S.; Hovy,E.; Levin,L.; Miller,K.J.; Mitamura,T.; others (Proceedings of the Fifth International Conference on Language Resources and Evaluation (LREC2006). Genoa, Italy, 2006)
This paper describes an effort to investigate the incrementally deepening development of an interlingua notation, validated by humanannotation of texts in English plus six languages. We begin with deep syntactic annotation, and in this paper present a series of annotation manuals for six different languages at the deep-syntactic level of representation. Many syntactic differences between languages are removed in the proposed syntactic annotation, making them useful resources for multilingual NLP projects with semantic components.

Participatory design with proxies: developing a desktop-PDA system to support people with aphasia - Jordan Boyd-Graber; Nikolova,Sonya S.; Moffatt,Karyn A.; Kin,Kenrick C.; Lee,Joshua Y.; Mackey,Lester W.; Tremaine,Marilyn M.; Klawe,Maria M. (Proceedings of the SIGCHI conference on Human Factors in computing systems, 2006)
In this paper, we describe the design and preliminary evaluation of a hybrid desktop-handheld system developed to support individuals with aphasia, a disorder which impairs the ability to speak, read, write, or understand language. The system allows its users to develop speech communication through images and sound on a desktop computer and download this speech to a mobile device that can then support communication outside the home. Using a desktop computer for input addresses some of this population's difficulties interacting with handheld devices, while the mobile device addresses stigma and portability issues. A modified participatory design approach was used in which proxies, that is, speech-language pathologists who work with aphasic individuals, assumed the role normally filled by users. This was done because of the difficulties in communicating with the target population and the high variability in aphasic disorders. In addition, the paper presents a case study of the proxy-use participatory design process that illustrates how different interview techniques resulted in different user feedback.
Keywords: aphasia; assistive technology; multi-modal interfaces; participatory design

PCFGs with syntactic and prosodic indicators of speech repairs - Hale,John; Shafran,Izhak; Yung,Lisa; Dorr, Bonnie J; Harper,Mary; Krasnyanskaya,Anna; Lease,Matthew; Liu,Yang; Roark,Brian; Snover,Matthew; Stewart,Robin (Proceedings of the 21st International Conference on Computational Linguistics and the 44th annual meeting of the Association for Computational Linguistics, 2006)
A grammatical method of combining two kinds of speech repair cues is presented. One cue, prosodic disjuncture, is detected by a decision tree-based ensemble classifier that uses acoustic cues to identify where normal prosody seems to be interrupted (Lickley, 1996). The other cue, syntactic parallelism, codifies the expectation that repairs continue a syntactic category that was left unfinished in the reparandum (Levelt, 1983). The two cues are combined in a Treebank PCFG whose states are split using a few simple tree transformations. Parsing performance on the Switchboard and Fisher corpora suggests that these two cues help to locate speech repairs in a synergistic way.

A probabilistic analysis of trie-based sorting of large collections of line segments in spatial databases - Lindenbaum,M.; Samet, Hanan; Hjaltason,G. R (SIAM Journal on Computing, 2006)

Probabilistic, Logical and Relational Learning-Towards a Synthesis - De Raedt,L.; Dietterich,T.; Getoor, Lise; Muggleton,S. H; Lloyd,J. W; Sears,T. D; Milch,B.; Marthi,B.; Russell,S.; Sontag,D. (Dagstuhl Seminar Proceedings, 2006)

Proximity problems on line segments spanned by points - Daescu,Ovidiu; Luo,Jun; Mount, Dave (Computational Geometry, 2006)
Finding the closest or farthest line segment (line) from a point are fundamental proximity problems. Given a set S of n points in the plane and another point q, we present optimal O ( n log n ) time, O ( n ) space algorithms for finding the closest and farthest line segments (lines) from q among those spanned by the points in S. We further show how to apply our techniques to find the minimum (maximum) area triangle with a vertex at q and the other two vertices in S ∖ { q } in optimal O ( n log n ) time and O ( n ) space. Finally, we give an O ( n log n ) time, O ( n ) space algorithm to find the kth closest line from q and show how to find the k closest lines from q in O ( n log n + k ) time and O ( n + k ) space.
Keywords: Closest; Farthest; k closest lines; Minimum (maximum) area triangle; Proximity problem

Query-time entity resolution - BHATTACHARVA,I.; Getoor, Lise; Licamele,L. (International conference on knowledge discovery and data mining, 2006)
The goal of entity resolution is to reconcile database references corresponding to the same real-world entities. Given the abundance of publicly available databases where entities are not resolved, we motivate the problem of quickly processing queries that require resolved entities from such 'unclean' databases. We propose a two-stage collective resolution strategy for processing queries. We then show how it can be performed on-the-fly by adaptively extracting and resolving those database references that are the most helpful for resolving the query. We validate our approach on two large real-world publication databases where we show the usefulness of collective resolution and at the same time demonstrate the need for adaptive strategies for query processing. We then show how the same queries can be answered in real time using our adaptive approach while preserving the gains of collective resolution.

Relational clustering for entity resolution queries - Bhattacharya,I.; Licamele,L.; Getoor, Lise (ICML 2006 Workshop on Statistical Relational Learning (SRL), 2006)
The goal of entity resolution is to recon-cile database references corresponding to the same real-world entities. Given the abun- dance of publicly available databases where entities are not resolved, we motivate the problem of quickly processing queries that require resolved entities from such ‘unclean’ databases. We first propose a cut-based rela- tional clustering formulation for collective en- tity resolution. We then show how it can be performed on-the-fly by adaptively extract- ing and resolving those database references that are the most helpful for resolving the query. We validate our approach on two large real-world publication databases, where we show the usefulness of collective resolution and at the same time demonstrate the need for adaptive strategies for query processing. We then show how the same queries can be answered in real time using our adaptive ap- proach while preserving the gains of collective resolution.

Reranking for Sentence Boundary Detection in Conversational Speech - Roark,B.; Liu,Yang; Harper,M.; Stewart,R.; Lease,M.; Snover,M.; Shafran,I.; Dorr, Bonnie J; Hale,J.; Krasnyanskaya,A.; Yung,L. (2006 IEEE International Conference on Acoustics, Speech and Signal Processing, 2006. ICASSP 2006 Proceedings, 2006)
We present a reranking approach to sentence-like unit (SU) boundary detection, one of the EARS metadata extraction tasks. Techniques for generating relatively small n-best lists with high oracle accuracy are presented. For each candidate, features are derived from a range of information sources, including the output of a number of parsers. Our approach yields significant improvements over the best performing system from the NIST RT-04F community evaluation
Keywords: Automatic speech recognition; conversational speech; data mining; Ear; EARS metadata extraction tasks; Feature extraction; hidden Markov models; meta data; Model driven engineering; NIST; NIST RT-04F community evaluation; oracle accuracy; performance evaluation; reranking; sentence-like unit boundary detection; Speech processing; Speech recognition; Telephony

Research-based web design & usability guidelines - Leavitt,M.O.; Shneiderman, Ben (Background and Methodology. US Department of Health and Human Services. Washington, 2006)

Resilient multicast using overlays - Banerjee,S.; Lee,Seungjoon; Bhattacharjee, Bobby; Srinivasan, Aravind (IEEE/ACM Transactions on Networking, 2006)
We introduce Probabilistic Resilient Multicast (PRM): a multicast data recovery scheme that improves data delivery ratios while maintaining low end-to-end latencies. PRM has both a proactive and a reactive components; in this paper we describe how PRM can be used to improve the performance of application-layer multicast protocols especially when there are high packet losses and host failures. Through detailed analysis in this paper, we show that this loss recovery technique has efficient scaling properties-the overheads at each overlay node asymptotically decrease to zero with increasing group sizes. As a detailed case study, we show how PRM can be applied to the NICE application-layer multicast protocol. We present detailed simulations of the PRM-enhanced NICE protocol for 10 000 node Internet-like topologies. Simulations show that PRM achieves a high delivery ratio (>97%) with a low latency bound (600 ms) for environments with high end-to-end network losses (1%-5%) and high topology change rates (5 changes per second) while incurring very low overheads (<5%).
Keywords: application-layer multicast protocols; Computer science; Data communication; Delay; Internet; Internet-like topologies; IP networks; loss recovery technique; Multicast; multicast data recovery scheme; Multicast protocols; Network topology; NETWORKS; overlays; Performance loss; probabilistic forwarding; probabilistic resilient multicast; Protocols; Resilience; Streaming media; telecommunication network topology; Terminology

Retroviral DNA Integration: Viral and Cellular Determinants of Target-Site Selection - Lewinski,Mary K; Yamashita,Masahiro; Emerman,Michael; Ciuffi,Angela; Marshall,Heather; Crawford,Gregory; Collins,Francis; Shinn,Paul; Leipzig,Jeremy; Hannenhalli, Sridhar; Berry,Charles C; Ecker,Joseph R; et al. (PLoS PathogPLoS Pathog, 2006)
Retroviruses differ in their preferences for sites for viral DNA integration in the chromosomes of infected cells. Human immunodeficiency virus (HIV) integrates preferentially within active transcription units, whereas murine leukemia virus (MLV) integrates preferentially near transcription start sites and CpG islands. We investigated the viral determinants of integration-site selection using HIV chimeras with MLV genes substituted for their HIV counterparts. We found that transferring the MLV integrase (IN) coding region into HIV (to make HIVmIN) caused the hybrid to integrate with a specificity close to that of MLV. Addition of MLV gag (to make HIVmGagmIN) further increased the similarity of target-site selection to that of MLV. A chimeric virus with MLV Gag only (HIVmGag) displayed targeting preferences different from that of both HIV and MLV, further implicating Gag proteins in targeting as well as IN. We also report a genome-wide analysis indicating that MLV, but not HIV, favors integration near DNase I–hypersensitive sites (i.e., +/− 1 kb), and that HIVmIN and HIVmGagmIN also favored integration near these features. These findings reveal that IN is the principal viral determinant of integration specificity; they also reveal a new role for Gag-derived proteins, and strengthen models for integration targeting based on tethering of viral IN proteins to host proteins.

The role of knowledge in conceptual retrieval: a study in the domain of clinical medicine - Jimmy Lin; Demner-Fushman,Dina (Proceedings of the 29th annual international ACM SIGIR conference on Research and development in information retrieval, 2006)
Despite its intuitive appeal, the hypothesis that retrieval at the level of "concepts" should outperform purely term-based approaches remains unverified empirically. In addition, the use of "knowledge" has not consistently resulted in performance gains. After identifying possible reasons for previous negative results, we present a novel framework for "conceptual retrieval" that articulates the types of knowledge that are important for information seeking. We instantiate this general framework in the domain of clinical medicine based on the principles of evidence-based medicine (EBM). Experiments show that an EBM-based scoring algorithm dramatically outperforms a state-of-the-art baseline that employs only term statistics. Ablation studies further yield a better understanding of the performance contributions of different components. Finally, we discuss how other domains can benefit from knowledge-based approaches.
Keywords: Question answering; reranking; semantic models

Routing for data delivery in dynamic networks - Mundur, Padma; Lee,S.; Seligman,M. (Proceedings of the IEEE MILCOM, 2006)

Routing in Delay Tolerant Networks Using Storage Domains - Mundur, Padma; Lee,Sookyoung; Seligman,Matthew (Instititue for Advanced Computer Studies, Univ of Maryland, College Park, 2006)
In this paper, we present a routing algorithm for a class ofdynamic networks called the Delay Tolerant Networks (DTNs). The proposed algorithm takes into account the quintessential DTN characteristic namely, intermittent link connectivity. We modify the breadth first search (BFS) algorithm to take into account link state changes and find the quickest route between source and destination nodes. We adopt a message drop policy at intermediate nodes to incorporate storage constraint. We also introduce the idea of time-varying storage domains where all nodes connected for a length of time act as a single storage unit by sharing the aggregated storage capacity of the nodes. We evaluate the routing algorithm with and without storage domain in an extensive simulation. We analyze the performance using metrics such as delivery ratio, incomplete transfers with no routes and dropped messages. The DTN topology dynamics are analyzed by varying: number of nodes generating traffic, link probability, link availability through combinations of downtime/uptime values, storage per node, message size, and traffic. The delay performance of the proposed algorithms is conceptually the same as flooding-based algorithms but without the penalty of multiple copies. More significantly, we show that the Quickest Storage Domain (Quickest SD) algorithm distributes the storage demand across many nodes in the network topology, enabling balanced load and higher network utilization. In fact, we show that for the same level of performance, we can actually cut the storage requirement in half using the Quickest SD algorithm.
Keywords: Technical Report

Routing in intermittent network topologies - Mundur, Padma; Lee,Sookyoung; Seligman,Matthew (Proceedings of the 9th ACM international symposium on Modeling analysis and simulation of wireless and mobile systems, 2006)
Keywords: delay tolerant network (DTN); performance evaluation; routing algorithms

A scalable key management and clustering scheme for ad hoc networks - Li,Jason H.; Levy,Renato; Yu,Miao; Bhattacharjee, Bobby (Proceedings of the 1st international conference on Scalable information systems, 2006)
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.

A Scalable Multiuser Framework for Video Over OFDM Networks: Fairness and Efficiency - Su,Guan-Ming; Han,Zhu; M. Wu; Liu,K. J.R (Circuits and Systems for Video Technology, IEEE Transactions on, 2006)
In this paper, we propose a framework to transmit multiple scalable video programs over downlink multiuser orthogonal frequency division multiplex (OFDM) networks in real time. The framework explores the scalability of the video codec and multidimensional diversity of multiuser OFDM systems to achieve the optimal service objectives subject to constraints on delay and limited system resources. We consider two essential service objectives, namely, the fairness and efficiency. Fairness concerns the video quality deviation among users who subscribe the same quality of service, and efficiency relates to how to attain the highest overall video quality using the available system resources. We formulate the fairness problem as minimizing the maximal end-to-end distortion received among all users and the efficiency problem as minimizing total end-to-end distortion of all users. Fast suboptimal algorithms are proposed to solve the above two optimization problems. The simulation results demonstrated that the proposed fairness algorithm outperforms a time division multiple (TDM) algorithm by 0.5 3 dB in terms of the worst received video quality among all users. In addition, the proposed framework can achieve a desired tradeoff between fairness and efficiency. For achieving the same average video quality among all users, the proposed framework can provide fairer video quality with 1 1.8 dB lower PSNR deviation than a TDM algorithm
Keywords: algorithm; video; codec; video; coding; video; communication; deviation; downlink; deviation; OFDM; distortion; multidimensional; diversity; multiple; division; end-to-end; framework; time; Frequency; modulation; diversity; multiple; multiplex; multiuser; network; efficiency; networks; video; objectives; optimization; of; OFDM; orthogonal; over; problem; fairness; problem; maximal; problems; quality; programs; multiuser; PSNR; QUALITY; reception; image; resolution; optimisation; quality; scalable; service; service; scalable; service; video; systems; optimal; video

Schistosoma mansoni (Platyhelminthes, Trematoda) nuclear receptors: Sixteen new members and a novel subfamily - Wu,Wenjie; Niles,Edward G.; El‐Sayed, Najib M.; Berriman,Matthew; LoVerde,Philip T. (Gene, 2006)
Nuclear receptors (NRs) are important transcriptional modulators in metazoans. Sixteen new NRs were identified in the Platyhelminth trematode, Schistosoma mansoni. Three were found to possess novel tandem DNA-binding domains that identify a new subfamily of NR. Two NRs are homologues of the thyroid hormone receptor that previously were thought to be restricted to chordates. This study brings the total number of identified NR in S. mansoni to 21. Phylogenetic and comparative genomic analyses demonstrate that S. mansoni NRs share an evolutionary lineage with that of arthropods and vertebrates. Phylogenic analysis shows that more than half of the S. mansoni nuclear receptors evolved from a second gene duplication. As the second gene duplication of NRs was thought to be specific to vertebrates, our data challenge the current theory of NR evolution.
Keywords: Nuclear receptors; Schistosoma mansoni

Script-Independent Text Line Segmentation in Freestyle Handwritten Documents - Li,Yi; Yefeng Zheng; David Doermann; Jaeger,Stefan (University of Maryland, College Park, 2006)
Text line segmentation in freestyle handwritten documents remains an open document analysis problem. Curvilinear text lines and small gaps between neighboring text lines present a challenge to algorithms developed for machine printed or hand-printed documents. In this paper, we propose a novel approach based on density estimation and a state-of-the-art image segmentation technique, the level set method. From an input document image, we estimate a probability map, where each element represents the probability that the underlying pixel belongs to a text line. The level set method is then exploited to determine the boundary of neighboring text lines by evolving an initial estimate. Unlike most connected component based methods [1, 2], the proposed algorithm does not use any script-specific knowledge. Extensive quantitative experiments on freestyle handwritten documents with diverse scripts, such as Arabic, Chinese, Korean, and Hindi, demonstrate that our algorithm consistently outperforms previous methods [3, 1, 2]. Further experiments show the proposed algorithm is robust to scale change, rotation, and noise.

Selection of Target Sites for Mobile DNA Integration in the Human Genome - Berry,Charles; Hannenhalli, Sridhar; Leipzig,Jeremy; Bushman,Frederic D. (PLoS Comput BiolPLoS Comput Biol, 2006)
DNA sequences from retroviruses, retrotransposons, DNA transposons, and parvoviruses can all become integrated into the human genome. Accumulation of such sequences accounts for at least 40% of our genome today. These integrating elements are also of interest as gene-delivery vectors for human gene therapy. Here we present a comprehensive bioinformatic analysis of integration targeting by HIV, MLV, ASLV, SFV, L1, SB, and AAV. We used a mathematical method which allowed annotation of each base pair in the human genome for its likelihood of hosting an integration event by each type of element, taking advantage of more than 200 types of genomic annotation. This bioinformatic resource documents a wealth of new associations between genomic features and integration targeting. The study also revealed that the length of genomic intervals analyzed strongly affected the conclusions drawn—thus, answering the question “What genomic features affect integration?” requires carefully specifying the length scale of interest.

A sensory grammar for inferring behaviors in sensor networks - Lymberopoulos, Dimitrios; Ogale, Abhijit S.; Savvides, Andreas; Aloimonos, J. (Proceedings of the 5th international conference on Information processing in sensor networks, 2006)
The ability of a sensor network to parse out observable activities into a set of distinguishable actions is a powerful feature that can potentially enable many applications of sensor networks to everyday life situations. In this paper we introduce a framework that uses a hierarchy of Probabilistic Context Free Grammars (PCFGs) to perform such parsing. The power of the framework comes from the hierarchical organization of grammars that allows the use of simple local sensor measurements for reasoning about more macroscopic behaviors. Our presentation describes how to use a set of phonemes to construct grammars and how to achieve distributed operation using a messaging model. The proposed framework is flexible. It can be mapped to a network hierarchy or can be applied sequentially and across the network to infer behaviors as they unfold in space and time. We demonstrate this functionality by inferring simple motion patterns using a sequence of simple direction vectors obtained from our camera sensor network testbed.
Keywords: algorithms; behavior identification; human activity; human factors; pcfg; real-time and embedded systems; sensor grammars; sensor networks

Sentence compression as a component of a multi-document summarization system - Zajic, David; Dorr, Bonnie J; Jimmy Lin; Schwartz,R. (Proceedings of the 2006 Document Understanding Workshop, New York, 2006)
We applied a single-document sentence-trimming approach (Trimmer) to the problem of multi-document summariza- tion. Trimmer was designed with the in- tention of compressing a lead sentence into a space consisting of tens of char- acters. In our Multi-Document Trimmer (MDT), we use Trimmer to generate multiple trimmed candidates for each sentence. Sentence selection is used to determine which trimmed candidates provide the best combination of topic coverage and brevity. We demonstrate that we were able to port Trimmer easily to this new problem. We also show that MDT generally ranked higher for recall than for precision, suggesting that MDT is currently more successful at finding relevant content than it is at weeding out irrelevant content. Finally, we present an error analysis that shows that, while sentence compressions is making space for additional sentences, more work is needed in the area of generating and se- lecting the right candidates.

Sentence Trimming and Selection: Mixing and Matching - Zajic, David; Dorr, Bonnie J; Jimmy Lin; O'Leary, Dianne P.; Conroy,John M.; Schlesinger,Judith D. (DUC 06 Conference Proceedings, 2006)
We describe how components from two distinct multi-document summarization systems were combined. Twenty four possible combinations of components were considered. We observed some contrasts between conservative and aggressive sentence compression (i.e., trimming) in the context of multi-document summarization.

Severity and impact of computer user frustration: A comparison of student and workplace users - Lazar,Jonathan; Jones,Adam; Hackley,Mary; Shneiderman, Ben (Interacting with Computers, 2006)
User frustration with information and computing technology is a pervasive and persistent problem. When computers crash, network congestion causes delays, and poor user interfaces trigger confusion there are dramatic consequences for individuals, organizations, and society. These frustrations, not only cause personal dissatisfaction and loss of self-efficacy, but may disrupt workplaces, slow learning, and reduce participation in local and national communities. Our exploratory study of 107 student computer users and 50 workplace computer users shows high levels of frustration and loss of 1/3–1/2 of time spent. This paper reports on the incident and individual factors that cause of frustration, and how they raise frustration severity. It examines the frustration impacts on the daily interactions of the users. The time lost and time to fix problem, and importance of task, strongly correlate with frustration levels for both student and workplace users. Differences between students and workplace users are discussed in the paper, as are implications for researchers.
Keywords: Computer anxiety; Computer experience; Helpdesk; Training; User frustration; user interface design

Social Capital in Friendship-Event Networks - Licamele,L.; Getoor, Lise (Data Mining, 2006. ICDM '06. Sixth International Conference on, 2006)
In this paper, we examine a particular form of social network which we call a friendship-event network. A friendship-event network captures both the friendship relationship among a set of actors, and also the organizer and participation relationships of actors in a series of events. Within these networks, we formulate the notion of social capital based on the actor-organizer friendship relationship and the notion of benefit, based on event participation. We investigate appropriate definitions for the social capital of both a single actor and a collection of actors. We ground these definitions in a real-world example of academic collaboration networks, where the actors are researchers, the friendships are collaborations, the events are conferences, the organizers are program committee members and the participants are conference authors. We show that our definitions of capital and benefit capture interesting qualitative properties of event series. In addition, we show that social capital is a better publication predictor than publication history.
Keywords: academic; based; capital; Internet; groupware; knowledge; Collaboration; friendship; friendship-event; network; actor-organizer; network; social; systems

SOFTCBIR: Object Searching in Videos Combining Keypoint Matching and Graduated Assignment - Luo,Ming; DeMenthon,Daniel; Yu,Xiaodong; David Doermann (University of Maryland, College Park, 2006)
This paper proposes a new approach to object searching in video databases, SoftCBIR, which combines a keypoint matching algorithm and a graduated assignment algorithm based on softassign. Compared with previous approaches, SoftCBIR is an innovative combination of two powerful techniques: 1) An energy minimization algorithm is applied to match two groups of keypoints while accounting for both their similarity in descriptor space and the consistency of their geometric configuration. The algorithm computes correspondence and pose transformation between two groups of keypoints iteratively and alternately toward an optimal result. The objective energy function combines normalized distance errors in descriptor space and in the spatial domain. 2) Initial individual keypoint matching relies on Approximate K-Nearest Neighbor (ANN) search. ANN achieves much more accurate initial keypoint matching results in the descriptor space than K-means labeling. Experiments prove the effectiveness of our approach, and demonstrate the performance improvements rising from the combination of the two proposed techniques in the SoftCBIR algorithm. The support of this research by the Department of Defense under contract MDA-9040-2C-0406 is gratefully acknowledged.

SParseval: Evaluation metrics for parsing speech - Roark,B.; Harper,M.; Charniak,E.; Dorr, Bonnie J; Johnson,M.; Kahn,J.; Liu,Y.; Ostendorf,M.; Hale,J.; Krasnyanskaya,A.; others (Proc. LREC, 2006)
While both spoken and written language processing stand to benefit from parsing, the standard Parseval metrics (Black et al., 1991) andtheir canonical implementation (Sekine and Collins, 1997) are only useful for text. The Parseval metrics are undefined when the words input to the parser do not match the words in the gold standard parse tree exactly, and word errors are unavoidable with automatic speech recognition (ASR) systems. To fill this gap, we have developed a publicly available tool for scoring parses that implements a variety of metrics which can handle mismatches in words and segmentations, including: alignment-based bracket evaluation, alignment-based dependency evaluation, and a dependency evaluation that does not require alignment. We describe the different metrics, how to use the tool, and the outcome of an extensive set of experiments on the sensitivity of the metrics.

Spherical and hemispherical microphone arrays for capture and analysis of sound fields - Duraiswami, Ramani; Zhiyun Li; Zotkin,Dmitry N; Grassi,Elena (The Journal of the Acoustical Society of America, 2006)
The capture of the spatial structure of a sound field and analysis is important in many fields including creating virtual environments, source localization and detection, noise suppression, and beamforming. Spherical microphone arrays are a promising development to help achieve such capture and analysis, and have been studied by several groups. We develop a practical spherical microphone array and demonstrate its utility in applications for sound capture, room measurement and for beamforming and tracking. To accommodate equipment failure and manufacturing imprecision we extend their theory to handle arbitrary microphone placement. To handle speech capture and surveillance we describe the development of a new sensor, the hemispherical microphone array. For each array the practical performance follows that predicted by theory. Future applications and improvements are also discussed. [Work supported by NSF.]

Structure From Planar Motion - Li,Jian; Chellapa, Rama (Image Processing, IEEE Transactions on, 2006)
Planar motion is arguably the most dominant type of motion in surveillance videos. The constraints on motion lead to a simplified factorization method for structure from planar motion when using a stationary perspective camera. Compared with methods for general motion , our approach has two major advantages: a measurement matrix that fully exploits the motion constraints is formed such that the new measurement matrix has a rank of at most 3, instead of 4; the measurement matrix needs similar scalings, but the estimation of fundamental matrices or epipoles is not needed. Experimental results show that the algorithm is accurate and fairly robust to noise and inaccurate calibration. As the new measurement matrix is a nonlinear function of the observed variables, a different method is introduced to deal with the directional uncertainty in the observed variables. Differences and the dual relationship between planar motion and planar object are also clarified. Based on our method, a fully automated vehicle reconstruction system has been designed
Keywords: algebra; road; analysis; matrix; camera; surveillance; directional; matrix; planar; MOTION; motion; stationary; perspective; processing; reconstruction; signal; system; image; uncertainty; measurement; vehicles; surveillance; video; videos; vehicle

Synthetic‐perturbation techniques for screening shared memory programs - Snelick,Robert; JaJa, Joseph F.; Kacker,Raghu; Lyon,Gordon (Software: Practice and Experience, 2006)
The synthetic-perturbation screening (SPS) methodology is based on an empirical approach; SPS introduces artificial perturbations into the MIMD program and captures the effects of such perturbations by using the modern branch of statistics called design of experiments. SPS can provide the basis of a powerful tool for screening MIMD programs for performance bottlenecks. This technique is portable across machines and architectures, and scales extremely well on massively parallel processors. The purpose of this paper is to explain the general approach and to extend it to address specific features that are the main source of poor performance on the shared memory programming model. These include performance degradation due to load imbalance and insufficient parallelism, and overhead introduced by synchronizations and by accessing shared data structures. We illustrate the practicality of SPS by demonstrating its use on two very different case studies: a large image understanding benchmark and a parallel quicksort.
Keywords: Design of experiments; parallel programs; performance; Shared memory programming model; Synthetic perturbation

SYSTEM AND METHOD FOR FAST ILLUMINATION-INVARIANT BACKGROUND SUBTRACTION USING TWO VIEWS - Davis, Larry S.; Lim,S.N.; Mittal,A. (2006)
A method for eliminating errors in foreground object detection in digitized images comprises providing (1101) 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 (1104) a foreground pixel in a reference view of a first point in a foreground object, finding (1105) a conjugate pixel of the foreground pixel in a secondary view, using (1106) 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 (1107) the foreground and image base pixels to find a location where the ground plane is first visible.

Task taxonomy for graph visualization - Lee,Bongshin; Plaisant, Catherine; Parr,Cynthia Sims; Fekete,Jean-Daniel; Henry,Nathalie (Proceedings of the 2006 AVI workshop on BEyond time and errors: novel evaluation methods for information visualization, 2006)
Our goal is to define a list of tasks for graph visualization that has enough detail and specificity to be useful to: 1) designers who want to improve their system and 2) to evaluators who want to compare graph visualization systems. In this paper, we suggest a list of tasks we believe are commonly encountered while analyzing graph data. We define graph specific objects and demonstrate how all complex tasks could be seen as a series of low-level tasks performed on those objects. We believe that our taxonomy, associated with benchmark datasets and specific tasks, would help evaluators generalize results collected through a series of controlled experiments.
Keywords: Evaluation; graph visualization; task taxonomy

Task-Driven Video Collection - Lim,Ser-Nam; Mittal,Anuarg; Davis, Larry S. (Technical Reports from UMIACS, 2006)
Vision systems are increasingly being deployed to perform complexsurveillance tasks. While improved algorithms are being developed to perform these tasks, it is also important that data suitable for these algorithms be acquired - a non-trivial task in a dynamic and crowded scene viewed by multiple PTZ cameras. In this paper, we describe a multi-camera system that collects images and videos of moving objects in such scenes, subject to task constraints. The system constructs "task visibility intervals" that contain information about what can be sensed in future time intervals. Constructing these intervals requires prediction of future object motion and consideration of several factors such as object occlusion and camera control parameters. Using a plane-sweep algorithm, these atomic intervals can be combined to form multi-task intervals, during which a single camera can collect videos suitable for multiple tasks simultaneously. Although cameras can then be scheduled based on the constructed intervals, finding an optimal schedule is a typical NP-hard problem. Due to this, and the lack of exact future information in a dynamic environment, we propose several methods for fast camera scheduling that yield solutions within a small constant factor of optimal. Experimental results illustrate system capabilities for both real and more complicated simulated scenarios.
Keywords: Technical Report

A Time Saving Method for Human Detection in Wide Angle Camera Images - Zhuolin Jiang; Li,Shao-Fa; Gao,Dong-Fa (Machine Learning and Cybernetics, 2006 International Conference on, 2006)
A time-saving method for human detection in an indoor environment in wide angle camera images is presented in this paper, without using time-consuming template operations such as edge detection and morphological operations. It excludes other objects in motion to detect humans including cases of the partial occlusion of humans, rotation of the head and variation of skin colors. This algorithm is applicable where the memory space is limited and the time requirements are strict, such as in an embedded system. The experimental results show that it took about 0.35 seconds to process the algorithm after the scene study time
Keywords: CAMERAS; Embedded system; human detection; image recognition; Image segmentation; indoor environment; Motion estimation; time-saving method; wide angle camera images

Toward an enriched (and revitalized) sense of help: Summary of an ASIS&T 2005 panel session - Haas,Stephanie W; Denn,Sheila; Locke,David; Shneiderman, Ben; Brown,Laurie (Bulletin of the American Society for Information Science and Technology, 2006)

TreePlus: Interactive Exploration of Networks with Enhanced Tree Layouts - Lee,B.; Parr,C.S.; Plaisant, Catherine; Bederson, Benjamin B.; Veksler,V.D.; Gray,W.D.; Kotfila,C. (Visualization and Computer Graphics, IEEE Transactions on, 2006)
Despite extensive research, it is still difficult to produce effective interactive layouts for large graphs. Dense layout and occlusion make food Webs, ontologies and social networks difficult to understand and interact with. We propose a new interactive visual analytics component called TreePlus that is based on a tree-style layout. TreePlus reveals the missing graph structure with visualization and interaction while maintaining good readability. To support exploration of the local structure of the graph and gathering of information from the extensive reading of labels, we use a guiding metaphor of "plant a seed and watch it grow." It allows users to start with a node and expand the graph as needed, which complements the classic overview techniques that can be effective at (but often limited to) revealing clusters. We describe our design goals, describe the interface and report on a controlled user study with 28 participants comparing TreePlus with a traditional graph interface for six tasks. In general, the advantage of TreePlus over the traditional interface increased as the density of the displayed data increased. Participants also reported higher levels of confidence in their answers with TreePlus and most of them preferred TreePlus
Keywords: Automated; Software; User-Computer Interface; Biological; Pattern Recognition; data visualization; graph structure; graphical user interface; interactive visual analytics; occlusion; tree-style layout; data visualisation; graphical user interfaces; hidden feature removal; interactive systems; trees (mathematics); Algorithms; Computer Graphics; C

VAST 2006 Contest - A Tale of Alderwood - Grinstein,G.; O'Connell,T.; Laskowski,S.; Plaisant, Catherine; Scholtz,J.; Whiting,M. (Visual Analytics Science And Technology, 2006 IEEE Symposium On, 2006)
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 first visual analytics science and technology (VAST) contest was held in conjunction with the 2006 IEEE VAST Symposium. The competition entailed the identification of possible political shenanigans in the fictitious town of Alderwood. A synthetic data set was made available as well as tasks. We summarize how we prepared and advertised the contest, developed some initial metrics for evaluation, and selected the winners. The winners were invited to participate at an additional live competition at the symposium to provide them with feedback from senior analysts
Keywords: Alderwood; human; analysis; data; analytics; and; contest; data; information; interaction; sense; making; visual; Science; technology; visualisation

Vertex–transformation streams - Kim,Youngmin; Lee,Chang Ha; Varshney, Amitabh (Graphical Models, 2006)
Recent trends in parallel computer architecture strongly suggest the need to improve the arithmetic intensity (the compute to bandwidth ratio) for greater performance in time-critical applications, such as interactive 3D graphics. At the same time, advances in stream programming abstraction for graphics processors (GPUs) have enabled us to use parallel algorithm design methods for GPU programming. Inspired by these developments, this paper explores the interactions between multiple data streams to improve arithmetic intensity and address the input geometry bandwidth bottleneck for interactive 3D graphics applications. We introduce the idea of creating vertex and transformation streams that represent large point datasets via their interaction. We discuss how to factor such point datasets into a set of source vertices and transformation streams by identifying the most common translations amongst vertices. We accomplish this by identifying peaks in the cross-power spectrum of the dataset in the Fourier domain. We validate our approach by integrating it with a view-dependent point rendering system and show significant improvements in input geometry bandwidth requirements as well as rendering frame rates.
Keywords: Arithmetic intensity; Geometry instancing; Stream programming; Streaming algorithms; Transformation encoding

Video Mensuration Using a Stationary Camera - Guo,Feng; Chellapa, Rama (Computer Vision – ECCV 2006Computer Vision – ECCV 2006, 2006)
This paper presents a method for video mensuration using a single stationary camera. The problem we address is simple, i.e., the mensuration of any arbitrary line segment on the reference plane using multiple frames with minimal calibration. Unlike previous solutions that are based on planar rectification, our approach is based on fitting the image of multiple concentric circles on the plane. Further, the proposed method aims to minimize the error in mensuration. Hence we can calculate the mensuration of the line segments not lying on the reference plane. Using an algorithm for detecting and tracking wheels of an automobile, we have implemented a fully automatic system for wheel base mensuration. The mensuration results are accurate enough that they can be used to determine the vehicle classes. Furthermore, we measure the line segment between any two points on the vehicle and plot them in top and side views.

Visualizing Graphs as Trees: Plant a Seed and Watch it Grow - Lee,Bongshin; Parr,Cynthia; Plaisant, Catherine; Bederson, Benjamin B. (Graph DrawingGraph Drawing, 2006)
TreePlus is a graph browsing technique based on a tree-style layout. It shows the missing graph structure using interaction techniques and enables users to start with a specific node and incrementally explore the local structure of graphs. We believe that it supports particularly well tasks that require rapid reading of labels.

Wavelet-Based Super-Resolution Reconstruction: Theory and Algorithm - Hui Ji; Fermüller, Cornelia (Computer Vision – ECCV 2006Computer Vision – ECCV 2006, 2006)
We present a theoretical analysis and a new algorithm for the problem of super-resolution imaging: the reconstruction of HR (high-resolution) images from a sequence of LR (low-resolution) images. Super-resolution imaging entails solutions to two problems. One is the alignment of image frames. The other is the reconstruction of a HR image from multiple aligned LR images. Our analysis of the latter problem reveals insights into the theoretical limits of super-resolution reconstruction. We find that at best we can reconstruct a HR image blurred by a specific low-pass filter. Based on the analysis we present a new wavelet-based iterative reconstruction algorithm which is very robust to noise. Furthermore, it has a computationally efficient built-in denoising scheme with a nearly optimal risk bound. Roughly speaking, our method could be described as a better-conditioned iterative back-projection scheme with a fast and optimal regularization criteria in each iteration step. Experiments with both simulated and real data demonstrate that our approach has significantly better performance than existing super-resolution methods. It has the ability to remove even large amounts of mixed noise without creating smoothing artifacts.

What Is the Range of Surface Reconstructions from a Gradient Field? - Agrawal,Amit; Raskar,Ramesh; Chellapa, Rama (Computer Vision – ECCV 2006Computer Vision – ECCV 2006, 2006)
We propose a generalized equation to represent a continuum of surface reconstruction solutions of a given non-integrable gradient field. We show that common approaches such as Poisson solver and Frankot-Chellappa algorithm are special cases of this generalized equation. For a N × N pixel grid, the subspace of all integrable gradient fields is of dimension N 2 – 1. Our framework can be applied to derive a range of meaningful surface reconstructions from this high dimensional space. The key observation is that the range of solutions is related to the degree of anisotropy in applying weights to the gradients in the integration process. While common approaches use isotropic weights, we show that by using a progression of spatially varying anisotropic weights, we can achieve significant improvement in reconstructions. We propose (a) α-surfaces using binary weights, where the parameter α allows trade off between smoothness and robustness, (b) M-estimators and edge preserving regularization using continuous weights and (c) Diffusion using affine transformation of gradients. We provide results on photometric stereo, compare with previous approaches and show that anisotropic treatment discounts noise while recovering salient features in reconstructions.

Will pyramids built of nuggets topple over? - Jimmy Lin; Demner-Fushman,Dina (Proceedings of the main conference on Human Language Technology Conference of the North American Chapter of the Association of Computational Linguistics, 2006)
The present methodology for evaluating complex questions at TREC analyzes answers in terms of facts called "nuggets". The official F-score metric represents the harmonic mean between recall and precision at the nugget level. There is an implicit assumption that some facts are more important than others, which is implemented in a binary split between "vital" and "okay" nuggets. This distinction holds important implications for the TREC scoring model---essentially, systems only receive credit for retrieving vital nuggets---and is a source of evaluation instability. The upshot is that for many questions in the TREC testsets, the median score across all submitted runs is zero. In this work, we introduce a scoring model based on judgments from multiple assessors that captures a more refined notion of nugget importance. We demonstrate on TREC 2003, 2004, and 2005 data that our "nugget pyramids" address many shortcomings of the present methodology, while introducing only minimal additional overhead on the evaluation flow.

Word-based alignment, phrase-based translation: What’s the link - Lopez,A.; Resnik, Philip (Proc. of AMTA, 2006)

Workplace user frustration with computers: an exploratory investigation of the causes and severity - Lazar,Jonathan; Jones,Adam; Shneiderman, Ben (Behaviour & Information Technology, 2006)
When hard-to-use computers cause users to become frustrated, it can affect workplace productivity, user mood and interactions with other co-workers. Previous research has examined the frustration that students and their families face in using computers. To learn more about the causes and measure the severity of user frustration with computers in the workplace, we collected modified time diaries from 50 workplace users, who spent an average of 5.1 hours on the computer. In this exploratory research, users reported wasting on average, 42 ? 43% of their time on the computer due to frustrating experiences. The largest number of frustrating experiences occurred while using word processors, email and web browsers. The causes of the frustrating experiences, the time lost due to the frustrating experiences, and the effects of the frustrating experiences on the mood of the users are discussed in this paper. Implications for designers, managers, users, information technology staff and policymakers are discussed.When hard-to-use computers cause users to become frustrated, it can affect workplace productivity, user mood and interactions with other co-workers. Previous research has examined the frustration that students and their families face in using computers. To learn more about the causes and measure the severity of user frustration with computers in the workplace, we collected modified time diaries from 50 workplace users, who spent an average of 5.1 hours on the computer. In this exploratory research, users reported wasting on average, 42 ? 43% of their time on the computer due to frustrating experiences. The largest number of frustrating experiences occurred while using word processors, email and web browsers. The causes of the frustrating experiences, the time lost due to the frustrating experiences, and the effects of the frustrating experiences on the mood of the users are discussed in this paper. Implications for designers, managers, users, information technology staff and policymakers are discussed.

Algorithms for constructing 3-D point clouds using multiple digital fringe projection patterns - Peng,T.; Gupta,S.K.; Lau,K. (Computer-Aided Design and Applications, 2005)
This paper describes algorithms for generating 3-D point clouds from a set of digital imagesobtained from projecting phase-shifted sinusoidal fringe patterns onto object. In this paper, a mathematical model is introduced for describing the geometric relationship between the fringe patterns being projected, the image captured and the shape of the object being measured. This model allows considerable flexibility in the spatial configuration of shape measurement system. The algorithms for point cloud construction described in this paper present an improvement over the existing algorithms in terms of accuracy, ease of system calibration, and sensitivity to parameter errors. These algorithms have been incorporated in a shape measurement system and shown to have a very good performance.

Anti-collusion forensics of multimedia fingerprinting using orthogonal modulation - Wang,Z.J.; M. Wu; Zhao,H.V.; Trappe,W.; Liu,K. J.R (Image Processing, IEEE Transactions on, 2005)
Digital fingerprinting is a method for protecting digital data in which fingerprints that are embedded in multimedia are capable of identifying unauthorized use of digital content. A powerful attack that can be employed to reduce this tracing capability is collusion, where several users combine their copies of the same content to attenuate/remove the original fingerprints. In this paper, we study the collusion resistance of a fingerprinting system employing Gaussian distributed fingerprints and orthogonal modulation. We introduce the maximum detector and the thresholding detector for colluder identification. We then analyze the collusion resistance of a system to the averaging collusion attack for the performance criteria represented by the probability of a false negative and the probability of a false positive. Lower and upper bounds for the maximum number of colluders Kmax are derived. We then show that the detectors are robust to different collusion attacks. We further study different sets of performance criteria, and our results indicate that attacks based on a few dozen independent copies can confound such a fingerprinting system. We also propose a likelihood-based approach to estimate the number of colluders. Finally, we demonstrate the performance for detecting colluders through experiments using real images.
Keywords: Automated; Product Labeling; Signal Processing; Computer-Assisted; Computer-Assisted; Multimedia; Patents as Topic; Pattern Recognition; Gaussian distribution; anticollusion forensic; colluder identification; collusion resistance; digital fingerprinting; false probability; likelihood-based approach; multimedia fingerprinting; orthogonal modulation; spread spectrum embedding; Gaussian distribution; fi

AParallel-Line Detection Algorithm Based on HMMDecoding - Yefeng Zheng; Huiping Li; David Doermann (IEEE Transactions on Pattern Analysis and Machine Intelligence, 2005)
The detection of groups of parallel lines is important in applications such as form processing and text (handwriting) extraction from rule lined paper. These tasks can be very challenging in degraded documents where the lines are severely broken. In this paper we propose a novel model-based method which incorporates high level context to detect these lines. After preprocessing (such as skew correction and text filtering), we use trained Hidden Markov Models (HMM) to locate the optimal positions of all lines simultaneously on the horizontal or vertical projection profiles, based on the Viterbi decoding. The algorithm is trainable so it can be easily adapted to different application scenarios. The experiments conducted on known form processing and rule line detection show our method is robust, and achieves better results than other widely used line detection methods.

Appearance modeling under geometric context - Li,Jian; Zhou,S. K; Chellapa, Rama (Computer Vision, 2005. ICCV 2005. Tenth IEEE International Conference on, 2005)
We propose a unified framework based on a general definition of geometric transform (GeT) for modeling appearance. GeT represents the appearance by applying designed functionals over certain geometric sets. We show that image warping, Radon transform, trace transform, etc. are special cases of our definition. Moreover, three different types of GeTs are designed to handle deformation, articulation and occlusion and applied to fingerprinting the appearance inside a contour. They include the contour-driven GeT, the feature curve based GeT and selecting functionals to model the appearance inside the convex hull of the contour. A multi-resolution representation that combines both shape and appearance information is also proposed. We apply our approach to image synthesis and object recognition. The proposed approach produces promising results when applied to fingerprinting the appearance of human and body parts despite the challenges due to articulated motion and deformations
Keywords: based; curve; geometry; image; GeT; convex; GeT; fingerprinting; geometric; hull; feature; information; trace; modeling; contour-driven; Radon; recognition; recognition; shape; representation; object; synthesis; image; transform; appearance; transform; image; transform; Radon; transforms; computational; warping; multi-resolution

Are GSM phones THE solution for localization? - Varshavsky,A.; Chen,M.Y.; de Lara,E.; Jon Froehlich; Haehnel,D.; Hightower,J.; LaMarca,A.; Potter,F.; Sohn,T.; Tang,K.; others (Mobile Computing Systems and Applications, 2006. WMCSA'06. Proceedings. 7th IEEE Workshop on, 2005)

Camera-Based Analysis of Text and Documents: ASurvey - Liang,Jian; David Doermann; Huiping Li (International Journal on Document Analysis and Recognition, 2005)

Capital and benefit in social networks - Licamele,Louis; Bilgic,Mustafa; Getoor, Lise; Roussopoulos, Nick (Proceedings of the 3rd international workshop on Link discovery, 2005)
Recently there has been a surge of interest in social networks. Email traffic, disease transmission, and criminal activity can all be modeled as social networks. In this paper, we introduce a particular form of social network which we call a friendship-event network. A friendship-event network describes two inter-related networks. One is a friendship network among a set of actors. The other is an event network that describes events, event organizers and event participants. Within these types of networks, we formulate the notion of capital based on the actor-organizer friendship relationship and the notion of benefit, based on event participation. We ground these definitions in a real-world example of academic collaboration networks, where the actors are researchers, the friendships are collaborations, the events are conferences, the organizers are program committee members and the participants are conference authors. We incorporate a temporal component by considering the notion of an event series. We explore the use of these measures on a data set describing three computer science conferences over the past ten years.

Collusion resistance analysis of multimedia fingerprinting systems - Wang,Z.J.; Wu,M.; Zhao,H.V.; Trappe,W.; Liu,K. J.R (IEEE Tran. on Image Processing, 2005)

Constructing task visibility intervals for a surveillance system - Lim,Ser-Nam; Mittal,Anurag; Davis, Larry S. (Proceedings of the third ACM international workshop on Video surveillance & sensor networks, 2005)
One of the goals of a multi-camera surveillance system is to collect useful video clips of objects in the scene. Objects in the collected videos should be unobstructed, in the field of view of the given camera, and meet task-specific resolution requirement. For this purpose, we describe an algorithm that constructs "task visibility intervals", which are tuples of information about what to sense (task-object pairs), when to sense (feasible future temporal intervals to start a task) and how to sense (the camera to use and the corresponding viewing angles and focal length). The algorithm first looks for temporal intervals within which the angular extents of objects overlap each other, causing the object farthest from the given camera to be occluded. Outside these intervals, sub-intervals are then constructed such that feasible camera settings exist for capturing the object. Experimental results are provided to illustrate the system capabilities in constructing such task visibility intervals, followed by scheduling them using a greedy algorithm.
Keywords: scheduling; sensor

Content Index to Volume 18 - Kuniavsky,M.; Vaughan,M.; Bederson, Benjamin B.; Shneiderman, Ben; Rau,P.L.P.; from Menus,T.; Lane,D.M.; Napier,H.A.; Peres,S.C.; Sándor,A. (INTERNATIONAL JOURNAL OF HUMAN–COMPUTER INTERACTION, 2005)

Critical Factors Influencing the Occurrence of Vibrio Cholerae in the Environment of Bangladesh - Huq,Anwar; Sack,R. Bradley; Nizam,Azhar; Longini,Ira M.; Nair,G. Balakrish; Ali,Afsar; Morris,J. Glenn; Khan,M. N. Huda; Siddique,A. Kasem; Yunus,Mohammed; Albert,M. John; Sack,David A.; et al. (Applied and Environmental MicrobiologyAppl. Environ. Microbiol., 2005)
The occurrence of outbreaks of cholera in Africa in 1970 and in Latin America in 1991, mainly in coastal communities, and the appearance of the new serotype Vibrio cholerae O139 in India and subsequently in Bangladesh have stimulated efforts to understand environmental factors influencing the growth and geographic distribution of epidemic Vibrio cholerae serotypes. Because of the severity of recent epidemics, cholera is now being considered by some infectious disease investigators as a “reemerging” disease, prompting new work on the ecology of vibrios. Epidemiological and ecological surveillance for cholera has been under way in four rural, geographically separated locations in Bangladesh for the past 4 years, during which both clinical and environmental samples were collected at biweekly intervals. The clinical epidemiology portion of the research has been published (Sack et al., J. Infect. Dis. 187:96-101, 2003). The results of environmental sampling and analysis of the environmental and clinical data have revealed significant correlations of water temperature, water depth, rainfall, conductivity, and copepod counts with the occurrence of cholera toxin-producing bacteria (presumably V. cholerae). The lag periods between increases or decreases in units of factors, such as temperature and salinity, and occurrence of cholera correlate with biological parameters, e.g., plankton population blooms. The new information on the ecology of V. cholerae is proving useful in developing environmental models for the prediction of cholera epidemics.

Data Redistribution and Remote Method Invocation in Parallel Component Architectures - Bertrand,Felipe; Bramley,Randall; Sussman, Alan; Bernholdt,David E.; Kohl,James A.; Larson,Jay W.; Damevski,Kostadin B. (Parallel and Distributed Processing Symposium, International, 2005)
With the increasing availability of high-performance massively parallel computer systems, the prevalence of sophisticated scientific simulation has grown rapidly. The complexity of the scientific models being simulated has also evolved, leading to a variety of coupled multi-physics simulation codes. Such cooperating parallel programs require fundamentally new interaction capabilities, to efficiently exchange parallel data structures and collectively invoke methods across programs. So-called "M?N" research, as part of the Common Component Architecture (CCA) effort, addresses these special and challenging needs, to provide generalized interfaces and tools that support flexible parallel data redistribution and parallel remote method invocation. Using this technology, distinct simulation codes with disparate distributed data decompositions can work together to achieve greater scientific discoveries.

Deformation invariant image matching - Ling,Haibin; Jacobs, David W. (Computer Vision, 2005. ICCV 2005. Tenth IEEE International Conference on, 2005)
We propose a novel framework to build descriptors of local intensity that are invariant to general deformations. In this framework, an image is embedded as a 2D surface in 3D space, with intensity weighted relative to distance in x-y. We show that as this weight increases, geodesic distances on the embedded surface are less affected by image deformations. In the limit, distances are deformation invariant. We use geodesic sampling to get neighborhood samples for interest points, and then use a geodesic-intensity histogram (GIH) as a deformation invariant local descriptor. In addition to its invariance, the new descriptor automatically finds its support region. This means it can safely gather information from a large neighborhood to improve discriminability. Furthermore, we propose a matching method for this descriptor that is invariant to affine lighting changes. We have tested this new descriptor on interest point matching for two data sets, one with synthetic deformation and lighting change, and another with real non-affine deformations. Our method shows promising matching results compared to several other approaches
Keywords: deformation; deformations; nonaffine; deformations; point; descriptor; geodesic; distances; geodesic; geometry; differential; geometry; image; histogram; image; image; invariant; local; matching; computational; matching; deformation; matching; image; morphing; sampling; geodesic-intensity

On degree constrained shortest paths - Khuller, Samir; Lee,K.; Shayman,M. (Algorithms–ESA 2005, 2005)
Traditional shortest path problems play a central role in both the design and use of communication networks and have been studied extensively. In this work, we consider a variant of the shortest path problem. The network has two kinds of edges, “actual” edges and “potential” edges. In addition, each vertex has a degree/interface constraint. We wish to compute a shortest path in the graph that maintains feasibility when we convert the potential edges on the shortest path to actual edges. The central difficulty is when a node has only one free interface, and the unconstrained shortest path chooses two potential edges incident on this node. We first show that this problem can be solved in polynomial time by reducing it to the minimum weighted perfect matching problem. The number of steps taken by this algorithm is O(|E|2 log |E|) for the single-source single-destination case. In other words, for each v we compute the shortest path P v such that converting the potential edges on P v to actual edges, does not violate any degree constraint. We then develop more efficient algorithms by extending Dijkstra’s shortest path algorithm. The number of steps taken by the latter algorithm is O(|E||V|), even for the single-source all destination case.

Determining Causes and Severity of End-User Frustration (2002) - Ceaparu,Irina; Lazar,Jonathan; Bessiere,Katie; Robinson,John; Shneiderman, Ben (Institute for Systems Research Technical Reports, 2005)
While computers are beneficial to individuals and society, frequently, users encounter frustrating experiences when using computers. This study attempts to measure, through 111 participants, the frequency, cause, and the level of severity of frustrating experiences. The data showed that frustrating experiences happen on a frequent basis. The applications in which the frustrating experiences happened most frequently were web browsing, e-mail, and word processing. The most-cited causes of frustrating experiences were error messages, dropped network connections, long download times, and hard-to-find features. The time lost due to frustrating experiences ranged from 47-53% of time spent on a computer depending on the location and study method. After discarding extreme cases the time lost was still above 38%. These disturbing results should be a basis for future study.
Keywords: Technical Report

Diagnostic problem solving using swarm intelligence - Lapizco-Encinas,G. C; Reggia, James A. (Swarm Intelligence Symposium, 2005. SIS 2005. Proceedings 2005 IEEE, 2005)

Dictionary-based cross-language retrieval - Levow,G.A.; Oard, Douglas; Resnik, Philip (Information Processing and Management, 2005)

Dictionary-based techniques for cross-language information retrieval - Levow,Gina-Anne; Oard, Douglas; Resnik, Philip (Information Processing & Management, 2005)
Cross-language information retrieval (CLIR) systems allow users to find documents written in different languages from that of their query. Simple knowledge structures such as bilingual term lists have proven to be a remarkably useful basis for bridging that language gap. A broad array of dictionary-based techniques have demonstrated utility, but comparison across techniques has been difficult because evaluation results often span only a limited range of conditions. This article identifies the key issues in dictionary-based CLIR, develops unified frameworks for term selection and term translation that help to explain the relationships among existing techniques, and illustrates the effect of those techniques using four contrasting languages for systematic experiments with a uniform query translation architecture. Key results include identification of a previously unseen dependence of pre- and post-translation expansion on orthographic cognates and development of a query-specific measure for translation fanout that helps to explain the utility of structured query methods.
Keywords: Cross-language information retrieval; Dictionary-based translation; Ranked retrieval

Differentiated traffic engineering for QoS provisioning - Tabatabaee,V.; Bhattacharjee, Bobby; La,R.J.; Shayman,M.A. (INFOCOM 2005. 24th Annual Joint Conference of the IEEE Computer and Communications Societies. Proceedings IEEE, 2005)
We introduce a new approach for QoS provisioning in packet networks based on the notion of differentiated traffic engineering (DTE). We consider a single AS network capable of source based multi-path routing. We do not require sophisticated queuing or per-class scheduling at individual routers; instead, if a link is used to forward QoS sensitive packets, we maintain its utilization below a threshold. As a consequence, DTE eliminates the need for per-flow (IntServ) or per-class (DiffServ) packet processing tasks such as traffic classification, queueing, shaping, policing and scheduling in the core and hence poses a lower burden on the network management unit. Conversely, DTE utilizes network bandwidth much more efficiently than simple over-provisioning. In this paper, we propose a complete architecture and an algorithmic structure for DTE. We show that our scheme can be formulated as a non-convex optimization problem, and we present an optimal solution framework based on simulated annealing. We present a simulation-based performance evaluation of DTE, and compare our scheme to existing (gradient projection) methods.
Keywords: based; Computer; differentiated; DiffServ; DTE; engineering; evaluation; link; links; management; multipath; network; networks; nonconvex; of; optimisation; OPTIMIZATION; packet; performance; problem; provisioning; QoS; QUALITY; routing; service; simulation-based; source; Telecommunication; traffic; traffic

Distributed Algorithms for Dynamic Survivability of Multiagent Systems - Subrahmanian,V.; Kraus,Sarit; Zhang,Yingqian (Computational Logic in Multi-Agent SystemsComputational Logic in Multi-Agent Systems, 2005)
Though multiagent systems (MASs) are being increasingly used, few methods exist to ensure survivability of MASs. All existing methods suffer from two flaws. First, a centralized survivability algorithm (CSA) ensures survivability of the MAS – unfortunately, if the node on which the CSA exists goes down, the survivability of the MAS is questionable. Second, no mechanism exists to change how the MAS is deployed when external factors trigger a re-evaluation of the survivability of the MAS. In this paper, we present three algorithms to address these two important problems. Our algorithms can be built on top of any CSA. Our algorithms are completely distributed and can handle external triggers to compute a new deployment. We report on experiments assessing the efficiency of these algorithms.
Keywords: Computer; Science

DSP address optimization using evolutionary algorithms - Leventhal,S.; Yuan,L.; Bambha,N. K; Bhattacharyya, Shuvra S.; Qu,G. (Proceedings of the 2005 workshop on Software and compilers for embedded systems, 2005)

Efficient geographic routing in multihop wireless networks - Lee,Seungjoon; Bhattacharjee, Bobby; Banerjee,Suman (Proceedings of the 6th ACM international symposium on Mobile ad hoc networking and computing, 2005)
We propose a new link metric called normalized advance (NADV) for geographic routing in multihop wireless networks. NADV selects neighbors with the optimal trade-off between proximity and link cost. Coupled with the local next hop decision in geographic routing, NADV enables an adaptive and efficient cost-aware routing strategy. Depending on the objective or message priority, applications can use the NADV framework to minimize various types of link cost.We present efficient methods for link cost estimation and perform detailed simulations in diverse scenarios. Our results show that NADV outperforms current schemes in many aspects: for example, in high noise environments with frequent packet losses, the use of NADV leads to 81% higher delivery ratio. When compared to centralized routing under certain settings, geographic routing using NADV finds paths whose cost is close to the optimum.
Keywords: Geographic routing; Link cost estimation; Routing metric; Wireless multihop networks

Envisioning help resources for the future information ecology: Toward an enriched sense of help - Haas,Stephanie W; Brown,Laurie; Denn,Sheila; Locke,David; Shneiderman, Ben (Proceedings of the American Society for Information Science and Technology, 2005)

On the equivalence of common approaches to lighting insensitive recognition - Osadchy,M.; Jacobs, David W.; Lindenbaum,M. (Computer Vision, 2005. ICCV 2005. Tenth IEEE International Conference on, 2005)
Lighting variation is commonly handled by methods invariant to additive and multiplicative changes in image intensity. It has been demonstrated that comparing images using the direction of the gradient can produce broader insensitivity to changes in lighting conditions, even for 3D scenes. We analyze two common approaches to image comparison that are invariant, normalized correlation using small correlation windows, and comparison based on a large set of oriented difference of Gaussian filters. We show analytically that these methods calculate a monotonic (cosine) function of the gradient direction difference and hence are equivalent to the direction of gradient method. Our analysis is supported with experiments on both synthetic and real scenes
Keywords: 3D; conditions; lighting; cosine; difference; image; direction; filters; gradient; function; image; insensitive; intensity; lighting; recognition; image; recognition; lighting; scenes; Gaussian; segmentation; variation; monotonic

Evaluating Summaries and Answers: Two Sides of the Same Coin? - Jimmy Lin; Demner-Fushman,D. (Intrinsic and Extrinsic Evaluation Measures for Machine Translation and/or Summarization, 2005)
This paper discusses the convergencebetween question answering and multi- document summarization, pointing out implications and opportunities for knowl- edge transfer in both directions. As a case study in one direction, we discuss the recent development of an automatic method for evaluating definition questions based on n-gram overlap, a commonly- used technique in summarization evalua- tion. In the other direction, the move to- wards topic-oriented summaries requires an understanding of relevance and topi- cality, issues which have received atten- tion in the question answering literature. It is our opinion that question answering and multi-document summarization repre- sent two complementary approaches to the same problem of satisfying complex user information needs. Although this points to many exciting opportunities for system- building, here we primarily focus on im- plications for system evaluation.

Evaluation Methodologies for Visual Analytics - Laskowski,S.; Plaisant, Catherine (Illuminating the Path: The Research and Development Agenda for Visual AnalyticsIlluminating the Path: The Research and Development Agenda for Visual Analytics, 2005)
Keywords: file-import-09-03-18

Evaluation of resources for question answering evaluation - Jimmy Lin (Proceedings of the 28th annual international ACM SIGIR conference on Research and development in information retrieval, 2005)
Controlled and reproducible laboratory experiments, enabled by reusable test collections, represent a well-established methodology in modern information retrieval research. In order to confidently draw conclusions about the performance of different retrieval methods using test collections, their reliability and trustworthiness must first be established. Although such studies have been performed for ad hoc test collections, currently available resources for evaluating question answering systems have not been similarly analyzed. This study evaluates the quality of answer patterns and lists of relevant documents currently employed in automatic question answering evaluation, and concludes that they are not suitable for post-hoc experimentation. These resources, created from runs submitted by TREC QA track participants, do not produce fair and reliable assessments of systems that did not participate in the original evaluations. Potential solutions for addressing this evaluation gap and their shortcomings are discussed.
Keywords: pooling; Question answering

An evolutionary testbed for software technology evaluation - Lindvall,M.; Rus,I.; Shull, F.; Zelkowitz, Marvin V; Donzelli,P.; Memon, Atif M.; Basili, Victor R.; Costa,P.; Tvedt,R.; Hochstein, L. (Innovations in Systems and Software Engineering, 2005)
Empirical evidence and technology evaluation are needed to close the gap between the state of the art and the state of the practice in software engineering. However, there are difficulties associated with evaluating technologies based on empirical evidence: insufficient specification of context variables, cost of experimentation, and risks associated with trying out new technologies. In this paper, we propose the idea of an evolutionary testbed for addressing these problems. We demonstrate the utility of the testbed in empirical studies involving two different research technologies applied to the testbed, as well as the results of these studies. The work is part of NASArsquos High Dependability Computing Project (HDCP), in which we are evaluating a wide range of new technologies for improving the dependability of NASA mission-critical systems.

Extending User Understanding of Federal Statistics in Tables (2000) - Marchionini,Gary; Hert,Carol; Liddy,Liz; Shneiderman, Ben (Institute for Systems Research Technical Reports, 2005)
This paper describes progress toward improving user interfaces for US Federal government statistics that are presented in tables. Based on studies of user behaviors and needs related to statistical tables, we describe interfaces to assist diverse users with a range of statistical literacy to explore, find, understand, and use US Federal government statistics.
Keywords: Technical Report

A Factorization Method for Structure from Planar Motion - Li,Jian; Chellapa, Rama (Application of Computer Vision, 2005. WACV/MOTIONS '05 Volume 1. Seventh IEEE Workshops on, 2005)
We propose a factorization method for structure from planar motion using a stationary perspective camera. Compared with [A factorization based algorithm for multi-image projective structure and motion] for general motion, our work has three major differences: a different measurement matrix specialized for planar motion is formed. The measurement matrix has a rank of at most 3, instead of 4; the measurement matrix needs similar scalings, but estimation of fundamental matrices or epipoles is not needed; we have an Euclidean reconstruction instead of a projective reconstruction. The camera is not required to be calibrated. A simple semi-automatic calibration method using vanishing points and lines is sufficient. Experimental results show that the algorithm is accurate and fairly robust to noise and inaccurate calibration.

Fast Camera Motion Estimation for Hand-Devices and Applications - Liu,Xu; David Doermann; Huiping Li (4th International Conference on Mobile and Ubiquitous Multimedia, 2005)
In this paper we present an efficient motion estimation algorithm for camera-enabled handheld devices, such as mobile phones and PDAs. Compared to general camera motion estimation, the estimation of ego-motion of handheld devices presents unique challenges because most devices are limited in resources (processing power, memory and battery). The algorithm must be lightweight so it can be efficiently embedded and run fast enough to produce smooth seamless translation. Our solution includes a multi-resolution scheme which searches the match from coarse to fine; and optimization of the search space. As a demonstration, we implemented the algorithm on the Symbian based Nokia 3650/6600 camera phone, and explored several interesting applications, including using camera motion for browsing documents and as a pointing device. A cross-platform implementation is also discussed.

Fast illumination-invariant background subtraction using two views: error analysis, sensor placement and applications - Lim,Ser-Nam; Mittal,A.; Davis, Larry S.; Paragios,N. (Computer Vision and Pattern Recognition, 2005. CVPR 2005. IEEE Computer Society Conference on, 2005)
Background modeling and subtraction to detect new or moving objects in a scene is an important component of many intelligent video applications. Compared to a single camera, the use of multiple cameras leads to better handling of shadows, specularities and illumination changes due to the utilization of geometric information. Although the result of stereo matching can be used as the feature for detection, it has been shown that the detection process can be made much faster by a simple subtraction of the intensities observed at stereo-generated conjugate pairs in the two views. The methodology however, suffers from false and missed detections due to some geometric considerations. In this paper, we perform a detailed analysis of such errors. Then, we propose a sensor configuration that eliminates false detections. Algorithms are also proposed that effectively eliminate most detection errors due to missed detections, specular reflections and objects being geometrically close to the background. Experiments on several scenes illustrate the utility and enhanced performance of the proposed approach compared to existing techniques.
Keywords: analysis; application; background; cameras; configuration; DETECTION; detection; error; error; extraction; false; feature; handling; illumination-invariance; image; intelligent; matching; modeling; object; placement; processing; sensor; sensors; shadow; stereo; subtraction; video

Flattening curved documents in images - Liang,Jian; DeMenthon,D.; David Doermann (Computer Vision and Pattern Recognition, 2005. CVPR 2005. IEEE Computer Society Conference on, 2005)
Compared to scanned images, document pictures captured by camera can suffer from distortions due to perspective and page warping. It is necessary to restore a frontal planar view of the page before other OCR techniques can be applied. In this paper we describe a novel approach for flattening a curved document in a single picture captured by an uncalibrated camera. To our knowledge this is the first reported method able to process general curved documents in images without camera calibration. We propose to model the page surface by a developable surface, and exploit the properties (parallelism and equal line spacing) of the printed textual content on the page to recover the surface shape. Experiments show that the output images are much more OCR friendly than the original ones. While our method is designed to work with any general developable surfaces, it can be adapted for typical special cases including planar pages, scans of thick books, and opened books.
Keywords: calibration; camera; character; content; curved; distortion; document; document; image; images; OCR; optical; page; pictures; printed; processing; recognition; restoration; scanned; techniques; textual; warping

Forensic analysis of nonlinear collusion attacks for multimedia fingerprinting - Zhao,H.V.; M. Wu; Wang,Z.J.; Liu,K. J.R (Image Processing, IEEE Transactions on, 2005)
Digital fingerprinting is a technology for tracing the distribution of multimedia content and protecting them from unauthorized redistribution. Unique identification information is embedded into each distributed copy of multimedia signal and serves as a digital fingerprint. Collusion attack is a cost-effective attack against digital fingerprinting, where colluders combine several copies with the same content but different fingerprints to remove or attenuate the original fingerprints. In this paper, we investigate the average collusion attack and several basic nonlinear collusions on independent Gaussian fingerprints, and study their effectiveness and the impact on the perceptual quality. With unbounded Gaussian fingerprints, perceivable distortion may exist in the fingerprinted copies as well as the copies after the collusion attacks. In order to remove this perceptual distortion, we introduce bounded Gaussian-like fingerprints and study their performance under collusion attacks. We also study several commonly used detection statistics and analyze their performance under collusion attacks. We further propose a preprocessing technique of the extracted fingerprints specifically for collusion scenarios to improve the detection performance.
Keywords: Automated; Product Labeling; Reproducibility of Results; Sensitivity and Specificity; Signal Processing; bounded Gaussian-like fingerprint; detection statistics; digital fingerprinting; forensic analysis; independent Gaussian fingerprint; multimedia content; multimedia fingerprinting; nonlinear collusion attack; perceptual distortion; perceptual quality; preprocessing; Computer-Assisted; Computer-Assisted; Models; Statistical; Nonlinear Dynamics; Patents as Topic; Pattern Recognition

The genome of the African trypanosome Trypanosoma brucei - Berriman,M.; Ghedin,E.; Hertz-Fowler,C.; Blandin,G.; Renauld,H.; Bartholomeu,D. C; Lennard,N. J; Caler,E.; Hamlin,N. E; Haas,B.; others (Science, 2005)

The genome of the protist parasite Entamoeba histolytica - Loftus,B.; Anderson,I.; Davies,R.; Alsmark,U. C.M; Samuelson,J.; Amedeo,P.; Roncaglia,P.; Berriman,M.; Hirt,R. P; Mann,B. J; others (Nature, 2005)

The Genome Sequence of Trypanosoma cruzi, Etiologic Agent of Chagas Disease - El‐Sayed, Najib M.; Myler,Peter J.; Bartholomeu,Daniella C.; Nilsson,Daniel; Aggarwal,Gautam; Tran,Anh-Nhi; Ghedin,Elodie; Worthey,Elizabeth A.; Delcher,Arthur L.; Blandin,Gaëlle; Westenberger,Scott J.; Caler,Elisabet; et al. (Science, 2005)
Whole-genome sequencing of the protozoan pathogen Trypanosoma cruzi revealed that the diploid genome contains a predicted 22,570 proteins encoded by genes, of which 12,570 represent allelic pairs. Over 50% of the genome consists of repeated sequences, such as retrotransposons and genes for large families of surface molecules, which include trans-sialidases, mucins, gp63s, and a large novel family (>1300 copies) of mucin-associated surface protein (MASP) genes. Analyses of the T. cruzi, T. brucei, and Leishmania major (Tritryp) genomes imply differences from other eukaryotes in DNA repair and initiation of replication and reflect their unusual mitochondrial DNA. Although the Tritryp lack several classes of signaling molecules, their kinomes contain a large and diverse set of protein kinases and phosphatases; their size and diversity imply previously unknown interactions and regulatory processes, which may be targets for intervention.

The Genome Sequence of Trypanosoma Cruzi, Etiologic Agent of Chagas Disease - El‐Sayed, Najib M.; Myler,Peter J.; Bartholomeu,Daniella C.; Nilsson,Daniel; Aggarwal,Gautam; Tran,Anh-Nhi; Ghedin,Elodie; Worthey,Elizabeth A.; Delcher,Arthur L.; Blandin,Gaëlle; Westenberger,Scott J.; Caler,Elisabet; et al. (ScienceScience, 2005)
Whole-genome sequencing of the protozoan pathogen Trypanosoma cruzi revealed that the diploid genome contains a predicted 22,570 proteins encoded by genes, of which 12,570 represent allelic pairs. Over 50% of the genome consists of repeated sequences, such as retrotransposons and genes for large families of surface molecules, which include trans-sialidases, mucins, gp63s, and a large novel family (>1300 copies) of mucin-associated surface protein (MASP) genes. Analyses of the T. cruzi, T. brucei, and Leishmania major (Tritryp) genomes imply differences from other eukaryotes in DNA repair and initiation of replication and reflect their unusual mitochondrial DNA. Although the Tritryp lack several classes of signaling molecules, their kinomes contain a large and diverse set of protein kinases and phosphatases; their size and diversity imply previously unknown interactions and regulatory processes, which may be targets for intervention.

Genome-Wide Analysis of Chromosomal Features Repressing Human Immunodeficiency Virus Transcription - Lewinski,M. K; Bisgrove,D.; Shinn,P.; Chen,H.; Hoffmann,C.; Hannenhalli, Sridhar; Verdin,E.; Berry,C. C; Ecker,J. R; Bushman,F. D (Journal of VirologyJ. Virol., 2005)
We have investigated regulatory sequences in noncoding human DNA that are associated with repression of an integrated human immunodeficiency virus type 1 (HIV-1) promoter. HIV-1 integration results in the formation of precise and homogeneous junctions between viral and host DNA, but integration takes place at many locations. Thus, the variation in HIV-1 gene expression at different integration sites reports the activity of regulatory sequences at nearby chromosomal positions. Negative regulation of HIV transcription is of particular interest because of its association with maintaining HIV in a latent state in cells from infected patients. To identify chromosomal regulators of HIV transcription, we infected Jurkat T cells with an HIV-based vector transducing green fluorescent protein (GFP) and separated cells into populations containing well-expressed (GFP-positive) or poorly expressed (GFP-negative) proviruses. We then determined the chromosomal locations of the two classes by sequencing 971 junctions between viral and cellular DNA. Possible effects of endogenous cellular transcription were characterized by transcriptional profiling. Low-level GFP expression correlated with integration in (i) gene deserts, (ii) centromeric heterochromatin, and (iii) very highly expressed cellular genes. These data provide a genome-wide picture of chromosomal features that repress transcription and suggest models for transcriptional latency in cells from HIV-infected patients.

Genome-wide analysis of retroviral DNA integration - Bushman,Frederic; Lewinski,Mary; Ciuffi,Angela; Barr,Stephen; Leipzig,Jeremy; Hannenhalli, Sridhar; Hoffmann,Christian (Nat Rev MicroNat Rev Micro, 2005)

Help! I'm Lost: User Frustration in Web Navigation (2003) - Lazar,Jonathan; Bessiere,Katie; Ceaparu,Irina; Robinson,John; Shneiderman, Ben (Institute for Systems Research Technical Reports, 2005)
Computers can be valuable tools, and networked resources via the Internet can be beneficial to many different populations and communities. Unfortunately, when people are unable to reach their task goals due to frustrating experiences, this can hinder the effectiveness of technology. This research summary provides information about the user frustration research that has been performed at the University of Maryland and Towson University. Causes of user frustration are discussed in this research summary, along with the surprising finding that nearly one-third to one-half of the time spent in front of the computer is wasted due to frustrating experiences. Furthermore, when interfaces are planned to be deceptive and confusing, this
Keywords: Technical Report

The Hiero machine translation system: Extensions, evaluation, and analysis - Chiang,D.; Lopez,A.; Madnani,N.; Monz,C.; Resnik, Philip; Subotin,M. (Proceedings of the conference on Human Language Technology and Empirical Methods in Natural Language Processing, 2005)

High Order Spatial Audio Capture and Binaural Head-Tracked Playback over Headphones with HRTF Cues - Duraiswami, Ramani; Zotkin,Dmitry N; Li,Z.; Grassi,E.; Gumerov, Nail A.; Davis, Larry S. (Proceedings 119th convention of AES, 2005)
A theory and a system for capturing an audio scene and then rendering it remotely are developed andpresented. The sound capture is performed with a spherical microphone array. The sound field at the location of the array is deduced from the captured sound and is represented using either spherical wave-functions or plane-wave expansions. The sound field representation is then transmitted to a remote location for immediate rendering or stored for later use. The sound renderer, coupled with the head tracker, reconstructs the acoustic field using individualized head-related transfer functions to preserve the perceptual spatial structure of the audio scene. Rigorous error bounds and Nyquist-like sampling criterion for the representation of the sound field are presented and verified.

High Order Spatial Audio Capture and Its Binaural Head-Tracked Playback Over Headphones with HRTF Cues - Davis, Larry S.; Duraiswami, Ramani; Grassi,E.; Gumerov, Nail A.; Li,Z.; Zotkin,Dmitry N (Audio Engineering Society Convention 119, 2005)
A theory and a system for capturing an audio scene and then rendering it remotely are developed and presented. The sound capture is performed with a spherical microphone array. The sound field at the location, and in a region of space in the neighborhood, of the array is deduced from the captured sound and represented using either spherical wave-functions or plane-wave expansions. The representation is then transmitted to a remote location for immediate rendering or stored for later reproduction. The sound renderer, coupled with the head tracker, reconstructs the acoustic field using individualized head-related transfer functions to preserve the perceptual spatial structure of the audio scene. Rigorous error bounds and a Nyquist-like sampling criterion for the representation of the sound field are presented and verified.

High Performance Communication between Parallel Programs - Jae-Yong Lee; Sussman, Alan (Parallel and Distributed Processing Symposium, 2005. Proceedings. 19th IEEE International, 2005)
We present algorithms for high performance communication between message-passing parallel programs, and evaluate the algorithms as implemented in InterComm. InterComm is a framework to couple parallel programs in the presence of complex data distributions within a coupled application. Multiple parallel libraries and languages may be used in the different programs of a single coupled application. The ability to couple such programs is required in many emerging application areas, such as complex simulations that model physical phenomena at multiple scales and resolutions, and image data analysis applications. We describe the new algorithms we have developed for computing inter-program communication patterns. We present experimental results showing the performance of various algorithmic tradeoffs, and also compare performance against an earlier system.
Keywords: Adaptive arrays; Analytical models; Chaotic communication; Computational modeling; Computer science; Data analysis; data distribution; Educational institutions; high performance communication; image data analysis; image resolution; inter-program communication patterns; InterComm; Libraries; Message passing; parallel languages; parallel libraries; parallel programming; parallel programs; performance evaluation; Wind

Improved HMM alignment models for languages with scarce resources - Lopez,A.; Resnik, Philip (Proceedings of the ACL Workshop on Building and Using Parallel Texts, 2005)

An interactive and team approach to multimedia design curriculum - M. Wu; Liu,K. J.R (Signal Processing Magazine, IEEE, 2005)
Over the past decade, increasingly powerful technologies have made it easier to compress, distribute, and store multimedia content. The merger of computing and communications has created a ubiquitous infrastructure that brings digital multimedia closer to the users and opens up tremendous educational and commercial opportunities in multimedia content creation, delivery, rendering, and archiving for millions of users worldwide. Multimedia has become a basic skill demanded by an increasing number of potential jobs for electrical engineering/computer science graduates. In this article, the authors intend to share their experiences and new ways of thinking about curriculum development. It is beneficial for colleagues in the multimedia signal processing areas for use in developing or revising the curriculum to fit the needs and resources of their own programs.
Keywords: approach; communication; courses; curriculum; curriculum; design; development; digital; education; educational; interactive; learning; multimedia; multimedia; processing; signal; team

Johns Hopkins summer workshop final report on parsing and spoken structural event detection - Harper,MP; Dorr, Bonnie J; Hale,J.; Roark,B.; Shafran,I.; Lease,M.; Liu,Y.; Snover,M.; Yung,L.; Krasnyanskaya,A. (Johns Hopkins University, Tech. Rep, 2005)
This report describes research conducted by the Parsing and Spoken Structural Event Detection(PaSSED) team as part of the 2005 Johns Hopkins Summer Workshop on Language Engineering. This project investigated the interaction between parsing and the detection of structural metadata in conversational speech, including sentence boundaries, edits (the reparandum portion of speech repairs), and fillers. In terms of parsing, we explored alternative methods of exploiting metadata information in parsing models and measured how varying accuracy in transcription and metadata information affects parsing accuracy. In the other direction, we similarly considered how syntactic and prosodic knowledge could be leveraged in metadata detection, measuring how this knowledge impacts metadata detection accuracy. As part of this work, we investigated metrics for evaluating parse accuracy in the presence of tran- scription and metadata detection errors, and we report on our experience using these metrics with several parsers and across varying experimental conditions. A range of methods for handling edits during pars- ing were evaluated in this research (excision, addition of markups to the input string, and grammar modification). We also developed a ToBI (a prosodic structure annotation scheme [SBP+92]) prosodic event classifier and describe its evaluation. Finally, we present methods for effective n-best sentence boundary candidate generation and reranking using syntactic, prosodic, and other features. These stud- ies are complemented by a second set of reranking investigations wherein we optimize sentence boundary detection explicitly to improve parse accuracy. The PaSSED project has: • investigated various techniques to enhance parsing of speech given metadata detection on conver- sational speech; • defined metrics for evaluating speech parsing accuracy, implemented them in the publically avail- able SParseval software package, and evaluated them under a wide variety of conditions; • recast SU detection as an n-best reranking problem with a relatively small n. Using this approach, we demonstrated significant improvements over a very strong baseline SU detection system. • reported on the interaction between parsing and metadata detection and their synergy; • fostered new collaborations and identified a number of interesting avenues for future work.

Joint uplink and downlink optimization for video conferencing over wireless LAN - Su,Guan-Ming; Han,Zhu; M. Wu; Liu,K. J.R (Acoustics, Speech, and Signal Processing, 2005. Proceedings. (ICASSP '05). IEEE International Conference on, 2005)
A real-time video conferencing framework is proposed for multiple conferencing pairs by jointly considering the uplink and downlink conditions within IEEE 802.11 networks. We formulate this system so as to minimize the maximal end-to-end expected distortion received by all users by selecting the PHY modes and transmission time. Compared with the strategy of individually optimizing uplink and downlink, the proposed framework outperforms by 3.67-8.65 dB for the average received PSNR among all users.
Keywords: 802.11; conferencing; conferencing; distortion; end-to-end; expected; IEEE; joint; LAN; maximal; minimisation; modes; multiple; networks; optimization; pairs; PHY; PSNR; real-time; teleconferencing; time; transmission; uplink-downlink; video; wireless

Link Mining for the Semantic Web, Position Statement - Getoor, Lise; Licamele,L. (Proceedings of the Dagstuhl Seminar in Machine Learning for the Semantic Web, 2005)
A key challenge for data mining is tackling the problem of mining richly structured datasets, where the objectsare linked in some way and we have some ontological information describing the domain. Links among the objects demonstrate certain patterns, which can be helpful for many data mining tasks and are usually hard to capture with traditional statistical models. Our goals are to develop machine learning algorithms which can a) make use of the ontological theory during learning b) learn how to refine, or update the ontological theory, based on learned model and c) do a mix of both.

Measurement-based multipath multicast - Guven,T.; La,R.J.; Shayman,M.A.; Bhattacharjee, Bobby (INFOCOM 2005. 24th Annual Joint Conference of the IEEE Computer and Communications Societies. Proceedings IEEE, 2005)
We propose a measurement-based routing algorithm to load balance intradomain traffic along multiple paths for multiple multicast sources. Multiple paths are established using application-layer overlaying. The proposed algorithm is able to converge under different network models, where each model reflects a different set of assumptions about the multicasting capabilities of the network. The algorithm is derived from simultaneous perturbation stochastic approximation and relies only on noisy estimates from measurements. Simulation results are presented to demonstrate the additional benefits obtained by incrementally increasing the multicasting capabilities.
Keywords: algorithm; allocation; application-layer; approximation; approximation; balance; communication; Convergence; convergence; intradomain; load; measurement-based; methods; Multicast; multipath; network; numerical; of; overlaying; perturbation; processes; resource; Routing; routing; source; Stochastic; techniques; Telecommunication; theory; traffic

Mesh saliency - Lee,Chang Ha; Varshney, Amitabh; Jacobs, David W. (ACM transactions on graphics, 2005)
Research over the last decade has built a solid mathematical foundation for representation and analysis of 3D meshes in graphics and geometric modeling. Much of this work however does not explicitly incorporate models of low-level human visual attention. In this paper we introduce the idea of mesh saliency as a measure of regional importance for graphics meshes. Our notion of saliency is inspired by low-level human visual system cues. We define mesh saliency in a scale-dependent manner using a center-surround operator on Gaussian-weighted mean curvatures. We observe that such a definition of mesh saliency is able to capture what most would classify as visually interesting regions on a mesh. The human-perception-inspired importance measure computed by our mesh saliency operator results in more visually pleasing results in processing and viewing of 3D meshes. compared to using a purely geometric measure of shape. such as curvature. We discuss how mesh saliency can be incorporated in graphics applications such as mesh simplification and viewpoint selection and present examples that show visually appealing results from using mesh saliency.
Keywords: perception; saliency; simplification; viewpoint selection; visual attention

Modeling image processing systems with homogeneous parameterized dataflow graphs - Sen,Mainak; Bhattacharyya, Shuvra S.; Lv,Tiehan; Wolf,W. (Acoustics, Speech, and Signal Processing, 2005. Proceedings. (ICASSP '05). IEEE International Conference on, 2005)
We describe a new dataflow model called homogeneous parameterized dataflow (HPDF). This form of dynamic dataflow graph takes advantage of the fact that in a large number of image processing applications, data production and consumption rates, though dynamic, are equal across graph edges for any particular iteration, which leads to a homogeneous rate of actor execution, even though data production and consumption values are dynamic and vary across graph edges. We discuss existing dataflow models and formulate in detail the HPDF model. We develop examples of applications that are described naturally in terms of HPDF semantics and present experimental results that demonstrate the efficacy of the HPDF approach.
Keywords: data consumption; data flow graphs; data production; dynamic dataflow graph; graph edges; homogeneous parameterized dataflow graphs; IMAGE PROCESSING; image processing system modeling; iteration; iterative methods

A new approach to image fusion based on cokriging - Memarsadeghi,N.; Le Moigne,J.; Mount, Dave; Morisette,J. (Information Fusion, 2005 8th International Conference on, 2005)
We consider the image fusion problem involving remotely sensed data. We introduce cokriging as a method to perform fusion. We investigate the advantages of fusing Hyperion with ALI. This evaluation is performed by comparing the classification of the fused data with that of input images and by calculating well-chosen quantitative fusion quality metrics. We consider the invasive species forecasting system (ISFS) project as our fusion application. The fusion of ALI with Hyperion data is studied using PCA and wavelet-based fusion. We then propose utilizing a geostatistical based interpolation method called cokriging as a new approach for image fusion.
Keywords: ALI; analysis; based; cokriging; component; data; forecasting; fusion; fusion; geophysical; geostatistical; Hyperion; image; Interpolation; interpolation; invasive; ISFS; method; metrics; PCA; principal; processing; project; QUALITY; quantitative; remote; remotely; sensed; sensing; sensor; sensors; signal; species; system; techniques; transforms; wavelet; wavelet-based

Pioneer: verifying code integrity and enforcing untampered code execution on legacy systems - Seshadri, Arvind; Luk, Mark; Elaine Shi; Perrig, Adrian; van Doorn, Leendert; Khosla, Pradeep (ACM SIGOPS Operating Systems Review, 2005)
We propose a primitive, called Pioneer, as a first step towards verifiable code execution on untrusted legacy hosts. Pioneer does not require any hardware support such as secure co-processors or CPU-architecture extensions. We implement Pioneer on an Intel Pentium IV Xeon processor. Pioneer can be used as a basic building block to build security systems. We demonstrate this by building a kernel rootkit detector.
Keywords: dynamic root of trust; rootkit detection; self-check-summing code; software-based code attestation; verifiable code execution

Plane-wave decomposition analysis for spherical microphone arrays - Duraiswami, Ramani; Zhiyun Li; Zotkin,Dmitry N; Grassi,E.; Gumerov, Nail A. (IEEE Workshop on Applications of Signal Processing to Audio and Acoustics, 2005, 2005)
Spherical microphone arrays have attracted attention for analyzing the sound field in a region and beamforming. The analysis of the recorded sound has been performed in terms of spherical wave-functions, and recently the use of plane-wave expansions has been suggested. We show that the plane-wave basis is intimately related to the spherical wave-functions. Reproduction in terms of both representations satisfies certain band-limit criteria. We provide an error bound that shows that to reproduce the spatial characteristics of a sound of a certain frequency we need to be able to accurately represent sounds of up to a particular order, which establishes a Nyquist-like criterion. The order of the sound field in turn is related to the number of microphones in the array necessary to achieve accurate quadrature on the sphere. These results are illustrated with simulations.
Keywords: Acoustic propagation; Acoustic scattering; acoustic signal processing; acoustic waves; array signal processing; band-limit criteria; beamforming; Educational institutions; Fourier transforms; Frequency; Laboratories; microphone arrays; Nails; Nyquist criterion; Nyquist-like criterion; Partial differential equations; plane-wave decomposition analysis; sound field analysis; spherical microphone arrays; spherical wave-functions

Promoter architecture and response to a positive regulator of archaeal transcription - Ouhammouch,Mohamed; Langham,Geoffrey E; Hausner,Winfried; Simpson,Anjana J.; El‐Sayed, Najib M.; Geiduschek,E. Peter (Molecular Microbiology, 2005)
The archaeal transcription apparatus is chimeric: its core components (RNA polymerase and basal factors) closely resemble those of eukaryotic RNA polymerase II, but the putative archaeal transcriptional regulators are overwhelmingly of bacterial type. Particular interest attaches to how these bacterial-type effectors, especially activators, regulate a eukaryote-like transcription system. The hyperthermophilic archaeon Methanocaldococcus jannaschii encodes a potent transcriptional activator, Ptr2, related to the Lrp/AsnC family of bacterial regulators. Ptr2 activates rubredoxin 2 (rb2) transcription through a bipartite upstream activating site (UAS), and conveys its stimulatory effects on its cognate transcription machinery through direct recruitment of the TATA binding protein (TBP). A functional dissection of the highly constrained architecture of the rb2 promoter shows that a ‘one-site’ minimal UAS suffices for activation by Ptr2, and specifies the required placement of this site. The presence of such a simplified UAS upstream of the natural rubrerythrin (rbr) promoter also suffices for positive regulation by Ptr2 in vitro, and TBP recruitment remains the primary means of transcriptional activation at this promoter.

Recovering from Intrusions in the OSPF Data-plane - Elaine Shi; Lu, Yong; Reid, Matt (Selected Project Reports, Spring 2005 Advanced OS & Distributed Systems (15-712), 2005)
In this paper, we propose CONS-ROUTE, a data-plane intrusion recoverymechanism for securing the OSPF routing protocol. CONS-ROUTE allows routers to perform intrusion detection in a distributed manner. The intrusion detection outcome can be used globally to reevaluate routing decisions in a way that is resilient to the slandering attack, where a malicious router claims that a legitimate router is misbehaving. We evaluate CONS-ROUTE through simulation and compare it with several simple OSPF data plane resilience techniques.

Representation of information needs and the elements of context: A case study in the domain of clinical medicine - Jimmy Lin; Fushman,D. D. (In Proceedings of the ACM SIGIR 2005 Workshop on Information Retrieval in Context (IRiX 2005), 2005)

Robotic apparatus and wireless communication system - Lathan,Corinna E.; Tracey,Michael R.; Vice,Jack M.; Druin, Allison; Plaisant, Catherine (2005)
A robotic apparatus and system adapted to communicate with a wireless sensor. The apparatus may be either physical or virtual in nature and is adapted to communicate physical movements with a wireless sensor. Data received from the sensor and/or robotic apparatus may be reviewed in a real-time mode, or may be saved for review at a later time. In addition, the apparatus may be controlled through an operator that is in local or remote communication with the apparatus. The robotic system may include pre-programmed interactive platforms for enabling communication between a user and the apparatus in a dynamic mode. In addition, the system may allow an operator to program a game/story for use as an interactive platform. Accordingly, the apparatus and system provides a platform for rehabilitative exercise of a patient as well as an entertainment device.