%0 Conference Paper %B 2011 IEEE International Conference on Computer Vision Workshops (ICCV Workshops) %D 2011 %T The evolution of stochastic grammars for representation and recognition of activities in videos %A Chellapa, Rama %K activity recognition %K activity representation %K Conferences %K Educational institutions %K Grammar %K Image analysis %K image recognition %K image representation %K image understanding %K pattern recognition %K stochastic image grammars %K syntactic pattern recognition methods %K video signal processing %K video understanding %K Videos %X The speaker is one of the privileged many to have been taught syntactic pattern recognition methods by the Late Prof. K.S. Fu. In this talk, I will discuss the evolution of stochastic image grammars from the early seventies to now with a focus on image and video understanding applications. %B 2011 IEEE International Conference on Computer Vision Workshops (ICCV Workshops) %I IEEE %P 688 - 688 %8 2011/11/06/13 %@ 978-1-4673-0062-9 %G eng %R 10.1109/ICCVW.2011.6130309 %0 Conference Paper %B 2011 International Conference on Embedded Computer Systems (SAMOS) %D 2011 %T Methods for design and implementation of dynamic signal processing systems %A Bhattacharyya, Shuvra S. %K actor invocation predictability %K complementary dataflow models %K Computational modeling %K computational structure %K COMPUTERS %K data flow graphs %K dataflow schedule graph %K DSG models %K DSP-powered products %K Dynamic scheduling %K dynamic scheduling techniques %K dynamic signal processing systems %K Educational institutions %K EIDF models %K enable-invoke dataflow %K formal dataflow semantics %K functionality structure %K Laboratories %K Maryland DSPCAD Research Group %K quasi-static schedules %K Schedules %K scheduling %K Signal processing %K static schedules %X Summary form only given. Dynamic signal processing systems, where significant changes in functionality and computational structure must be achieved while applications are running, are becoming increasingly important as computational platforms become more powerful, and feature-sets of DSP-powered products become more sophisticated. This talk covers two new, complementary dataflow models of computation that are being developed in the Maryland DSPCAD Research Group to help address the challenges of structured design, simulation, and synthesis of dynamic signal processing systems. The first of these models, called enable-invoke dataflow (EIDF), is aimed improving the predictability of actor invocation and the efficiency with which dynamic scheduling techniques can be realized. The second model, called the dataflow schedule graph (DSG), provides a formal framework for representing and analyzing dataflow graph schedules that is rooted in formal dataflow semantics, and accommodates a wide range of schedule classes, including static, quasi-static, and dynamic schedules, as well as both sequential and parallel schedule formats. In this talk, I will present the EIDF and DSG models and discuss their potential to improve the processes by which dynamic signal processing systems are developed. %B 2011 International Conference on Embedded Computer Systems (SAMOS) %P i - i %8 2011 %G eng %0 Conference Paper %B Privacy, Security, Risk and Trust (PASSAT), 2011 IEEE Third International Conference on and 2011 IEEE Third International Confernece on Social Computing (SocialCom) %D 2011 %T Simulating Audiences: Automating Analysis of Values, Attitudes, and Sentiment %A Templeton,T.C. %A Fleischmann,K.R. %A Jordan Boyd-Graber %K audience simulation %K behavioural sciences computing %K crowdsourcing %K Educational institutions %K human values %K HUMANS %K learning (artificial intelligence) %K machine learning %K moral argument %K natural language processing %K Park51 project %K Presses %K public controversy %K public discussion %K Security %K social sciences computing %K support vector machines %K Weaving %X Current events such as the Park51 Project in downtown Manhattan create "critical discourse moments," explosions of discourse around a topic that can be exploited for data gathering. Policymakers have a need to understand the dynamics of public discussion in real time. Human values, which are cognitively related to attitudes and serve as reference points in moral argument, are important indicators of what's at stake in a public controversy. This work shows that it is possible to link values data with reader behavior to infer values implicit in a topical corpus, and that it is possible to automate this process using machine learning. %B Privacy, Security, Risk and Trust (PASSAT), 2011 IEEE Third International Conference on and 2011 IEEE Third International Confernece on Social Computing (SocialCom) %I IEEE %P 734 - 737 %8 2011/10/09/11 %@ 978-1-4577-1931-8 %G eng %R 10.1109/PASSAT/SocialCom.2011.238 %0 Journal Article %J Communications Magazine, IEEE %D 2011 %T A survey of virtual LAN usage in campus networks %A Yu,Minlan %A Rexford,J. %A Sun,Xin %A Rao,Sanjay %A Feamster, Nick %K academic department %K campus network %K educational computing %K Educational institutions %K Ethernet scalability %K Local area networks %K network policy support %K university campus %K virtual LAN usage %K VLAN %X VLANs are widely used in today's enterprise networks to improve Ethernet scalability and support network policies. However, manuals and textbooks offer very little information about how VLANs are actually used in practice. Through discussions with network administrators and analysis of configuration data, we describe how three university campuses and one academic department use VLANs to achieve a variety of goals. We argue that VLANs are ill-suited to some of these goals (e.g., VLANs are often used to realize access control policies, but constrain the types of policies that can be expressed). Furthermore, the use of VLANs leads to significant complexity in the configuration of network devices. %B Communications Magazine, IEEE %V 49 %P 98 - 103 %8 2011/07// %@ 0163-6804 %G eng %N 7 %R 10.1109/MCOM.2011.5936161 %0 Conference Paper %B 2011 IEEE Conference on Visual Analytics Science and Technology (VAST) %D 2011 %T TreeVersity: Comparing tree structures by topology and node's attributes differences %A Gomez,J.A.G. %A Buck-Coleman,A. %A Plaisant, Catherine %A Shneiderman, Ben %K Computer science %K data classification %K Data visualization %K Educational institutions %K hierarchy %K Image color analysis %K LifeFlow %K node attributes differences %K Pattern classification %K structural changes %K Topology %K topology attributes differences %K traffic agencies %K tree structures comparison %K trees (mathematics) %K TreeVersity %K Vegetation %K Visualization %X It is common to classify data in hierarchies, they provide a comprehensible way of understanding big amounts of data. From budgets to organizational charts or even the stock market, trees are everywhere and people find them easy to use. However when analysts need to compare two versions of the same tree structure, or two related taxonomies, the task is not so easy. Much work has been done on this topic, but almost all of it has been restricted to either compare the trees by topology, or by the node attribute values. With this project we are proposing TreeVersity, a framework for comparing tree structures, both by structural changes and by differences in the node attributes. This paper is based on our previous work on comparing traffic agencies using LifeFlow [1, 2] and on a first prototype of TreeVersity. %B 2011 IEEE Conference on Visual Analytics Science and Technology (VAST) %I IEEE %P 275 - 276 %8 2011/10/23/28 %@ 978-1-4673-0015-5 %G eng %R 10.1109/VAST.2011.6102471 %0 Conference Paper %B 2010 Proceedings IEEE INFOCOM %D 2010 %T On Computing Compression Trees for Data Collection in Wireless Sensor Networks %A Li,Jian %A Deshpande, Amol %A Khuller, Samir %K Approximation algorithms %K Base stations %K Communications Society %K Computer networks %K Computer science %K computing compression trees %K Costs %K data collection %K Data communication %K data compression %K designing algorithms %K Educational institutions %K Entropy %K graph concept %K Monitoring %K Protocols %K trees (mathematics) %K weakly connected dominating sets %K Wireless sensor networks %X We address the problem of efficiently gathering correlated data from a wireless sensor network, with the aim of designing algorithms with provable optimality guarantees, and understanding how close we can get to the known theoretical lower bounds. Our proposed approach is based on finding an optimal or a near-optimal compression tree for a given sensor network: a compression tree is a directed tree over the sensor network nodes such that the value of a node is compressed using the value of its parent. We focus on broadcast communication model in this paper, but our results are more generally applicable to a unicast communication model as well. We draw connections between the data collection problem and a previously studied graph concept called weakly connected dominating sets, and we use this to develop novel approximation algorithms for the problem. We present comparative results on several synthetic and real-world datasets showing that our algorithms construct near-optimal compression trees that yield a significant reduction in the data collection cost. %B 2010 Proceedings IEEE INFOCOM %I IEEE %P 1 - 9 %8 2010/03/14/19 %@ 978-1-4244-5836-3 %G eng %R 10.1109/INFCOM.2010.5462035 %0 Conference Paper %B 2010 IEEE International Symposium on Parallel & Distributed Processing, Workshops and Phd Forum (IPDPSW) %D 2010 %T Decentralized dynamic scheduling across heterogeneous multi-core desktop grids %A Jaehwan Lee %A Keleher,P. %A Sussman, Alan %K backfill jobs %K bounded waiting time %K Computer science %K decentralized dynamic scheduling %K desktop grid resource management %K Dynamic scheduling %K Educational institutions %K Environmental management %K grid computing %K heterogeneous multicore desktop grid %K job assignment %K job migration %K load balancing %K Load management %K multicore computing environment %K Peer to peer computing %K Processor scheduling %K residual resources %K resource allocation %K Resource management %K scheduling %K Scheduling algorithm %K Throughput %X The recent advent of multi-core computing environments increases both the heterogeneity and complexity of managing desktop grid resources, making efficient load balancing challenging even for a centralized manager. Even with good initial job assignments, dynamic scheduling is still needed to adapt to dynamic environments, as well as for applications whose running times are not known a priori. In this paper, we propose new decentralized scheduling schemes that backfill jobs locally and dynamically migrate waiting jobs across nodes to leverage residual resources, while guaranteeing bounded waiting times for all jobs. The methods attempt to maximize total throughput while balancing load across available grid resources. Experimental results via simulation show that our scheduling scheme has performance competitive with an online centralized scheduler. %B 2010 IEEE International Symposium on Parallel & Distributed Processing, Workshops and Phd Forum (IPDPSW) %I IEEE %P 1 - 9 %8 2010/04/19/23 %@ 978-1-4244-6533-0 %G eng %R 10.1109/IPDPSW.2010.5470877 %0 Conference Paper %B 2010 IEEE Conference on Computer Vision and Pattern Recognition (CVPR) %D 2010 %T Moving vistas: Exploiting motion for describing scenes %A Shroff, N. %A Turaga,P. %A Chellapa, Rama %K Application software %K Automation %K Chaos %K chaotic system %K Computational modeling %K Computer vision %K dynamic scene categorization %K Educational institutions %K HUMANS %K image recognition %K in the wild dynamic scene %K Layout %K motion attribute %K natural scenes %K Physics %K probability %K scene recognition %K Snow %K video data %X Scene recognition in an unconstrained setting is an open and challenging problem with wide applications. In this paper, we study the role of scene dynamics for improved representation of scenes. We subsequently propose dynamic attributes which can be augmented with spatial attributes of a scene for semantically meaningful categorization of dynamic scenes. We further explore accurate and generalizable computational models for characterizing the dynamics of unconstrained scenes. The large intra-class variation due to unconstrained settings and the complex underlying physics present challenging problems in modeling scene dynamics. Motivated by these factors, we propose using the theory of chaotic systems to capture dynamics. Due to the lack of a suitable dataset, we compiled a dataset of `in-the-wild' dynamic scenes. Experimental results show that the proposed framework leads to the best classification rate among other well-known dynamic modeling techniques. We also show how these dynamic features provide a means to describe dynamic scenes with motion-attributes, which then leads to meaningful organization of the video data. %B 2010 IEEE Conference on Computer Vision and Pattern Recognition (CVPR) %I IEEE %P 1911 - 1918 %8 2010/06/13/18 %@ 978-1-4244-6984-0 %G eng %R 10.1109/CVPR.2010.5539864 %0 Conference Paper %B IEEE 25th International Conference on Data Engineering, 2009. ICDE '09 %D 2009 %T ApproxRank: Estimating Rank for a Subgraph %A Yao Wu %A Raschid, Louiqa %K Application software %K ApproxRank %K Computer applications %K Crawlers %K customized semantic query answering %K Data engineering %K Educational institutions %K Explosions %K focused crawlers %K global Web graph %K graph theory %K IdealRank algorithm %K Internet %K localized search engines %K PageRank-style %K personalized search %K Query processing %K Runtime %K Search engines %K Stochastic processes %K Web pages %X Customized semantic query answering, personalized search, focused crawlers and localized search engines frequently focus on ranking the pages contained within a subgraph of the global Web graph. The challenge for these applications is to compute PageRank-style scores efficiently on the subgraph, i.e., the ranking must reflect the global link structure of the Web graph but it must do so without paying the high overhead associated with a global computation. We propose a framework of an exact solution and an approximate solution for computing ranking on a subgraph. The IdealRank algorithm is an exact solution with the assumption that the scores of external pages are known. We prove that the IdealRank scores for pages in the subgraph converge. Since the PageRank-style scores of external pages may not typically be available, we propose the ApproxRank algorithm to estimate scores for the subgraph. Both IdealRank and ApproxRank represent the set of external pages with an external node L1 and extend the subgraph with links to L1. They also modify the PageRank-style transition matrix with respect to L1. We analyze the L1 distance between IdealRank scores and ApproxRank scores of the subgraph and show that it is within a constant factor of the L1 distance of the external pages (e.g., the true PageRank scores and uniform scores assumed by ApproxRank). We compare ApproxRank and a stochastic complementation approach (SC), a current best solution for this problem, on different types of subgraphs. ApproxRank has similar or superior performance to SC and typically improves on the runtime performance of SC by an order of magnitude or better. We demonstrate that ApproxRank provides a good approximation to PageRank for a variety of subgraphs. %B IEEE 25th International Conference on Data Engineering, 2009. ICDE '09 %I IEEE %P 54 - 65 %8 2009/04/29/March %@ 978-1-4244-3422-0 %G eng %R 10.1109/ICDE.2009.108 %0 Conference Paper %B IEEE INFOCOM 2009 %D 2009 %T Distributed Strategies for Channel Allocation and Scheduling in Software-Defined Radio Networks %A Han,Bo %A Kumar,V. S.A %A Marathe,M. V %A Parthasarathy,S. %A Srinivasan, Aravind %K access hash function %K Channel allocation %K channel assignment algorithm %K channel capacity %K collision avoidance %K Computer science %K cryptography %K distributed algorithm %K distributed algorithms %K Educational institutions %K inductive-scheduling technique %K Interference %K interference set %K packet scheduling algorithm %K Peer to peer computing %K Radio network %K radio networks %K radiofrequency interference %K random oracle methodology %K scheduling %K Scheduling algorithm %K simultaneous channel allocation %K software radio %K software-defined radio wireless network capacity %K telecommunication congestion control %K telecommunication security %K Throughput %K wireless channels %K Wireless networks %X Equipping wireless nodes with multiple radios can significantly increase the capacity of wireless networks, by making these radios simultaneously transmit over multiple non-overlapping channels. However, due to the limited number of radios and available orthogonal channels, designing efficient channel assignment and scheduling algorithms in such networks is a major challenge. In this paper, we present provably-good distributed algorithms for simultaneous channel allocation of individual links and packet-scheduling, in software-defined radio (SDR) wireless networks. Our distributed algorithms are very simple to implement, and do not require any coordination even among neighboring nodes. A novel access hash function or random oracle methodology is one of the key drivers of our results. With this access hash function, each radio can know the transmitters' decisions for links in its interference set for each time slot without introducing any extra communication overhead between them. Further, by utilizing the inductive-scheduling technique, each radio can also backoff appropriately to avoid collisions. Extensive simulations demonstrate that our bounds are valid in practice. %B IEEE INFOCOM 2009 %I IEEE %P 1521 - 1529 %8 2009/04/19/25 %@ 978-1-4244-3512-8 %G eng %R 10.1109/INFCOM.2009.5062069 %0 Conference Paper %B IEEE Symposium on Visual Analytics Science and Technology, 2009. VAST 2009 %D 2009 %T Finding comparable temporal categorical records: A similarity measure with an interactive visualization %A Wongsuphasawat,K. %A Shneiderman, Ben %K data visualisation %K Educational institutions %K Feedback %K Information retrieval %K interactive search tool %K interactive systems %K interactive visualization tool %K large databases %K M&M Measure %K Match & Mismatch measure %K Medical services %K numerical time series %K parameters customization %K Particle measurements %K Similan %K similarity measure %K Similarity Search %K temporal categorical databases %K Temporal Categorical Records %K temporal databases %K Testing %K Time measurement %K time series %K transportation %K usability %K very large databases %K visual databases %K Visualization %X An increasing number of temporal categorical databases are being collected: Electronic Health Records in healthcare organizations, traffic incident logs in transportation systems, or student records in universities. Finding similar records within these large databases requires effective similarity measures that capture the searcher's intent. Many similarity measures exist for numerical time series, but temporal categorical records are different. We propose a temporal categorical similarity measure, the M&M (Match & Mismatch) measure, which is based on the concept of aligning records by sentinel events, then matching events between the target and the compared records. The M&M measure combines the time differences between pairs of events and the number of mismatches. To accom-modate customization of parameters in the M&M measure and results interpretation, we implemented Similan, an interactive search and visualization tool for temporal categorical records. A usability study with 8 participants demonstrated that Similan was easy to learn and enabled them to find similar records, but users had difficulty understanding the M&M measure. The usability study feedback, led to an improved version with a continuous timeline, which was tested in a pilot study with 5 participants. %B IEEE Symposium on Visual Analytics Science and Technology, 2009. VAST 2009 %I IEEE %P 27 - 34 %8 2009/10/12/13 %@ 978-1-4244-5283-5 %G eng %R 10.1109/VAST.2009.5332595 %0 Conference Paper %B International Conference on Computational Science and Engineering, 2009. CSE '09 %D 2009 %T First Steps to Netviz Nirvana: Evaluating Social Network Analysis with NodeXL %A Bonsignore,E. M %A Dunne,C. %A Rotman,D. %A Smith,M. %A Capone,T. %A Hansen,D. L %A Shneiderman, Ben %K Computer science %K computer science education %K data visualisation %K Data visualization %K Educational institutions %K graph drawing %K graph layout algorithm %K Information services %K Information Visualization %K Internet %K Libraries %K Microsoft Excel open-source template %K MILC %K multi-dimensional in-depth long-term case studies %K Netviz Nirvana %K NodeXL %K Open source software %K Programming profession %K SNA %K social network analysis %K Social network services %K social networking (online) %K spreadsheet programs %K structural relationship %K teaching %K visual analytics %K visualization tool %K Web sites %X Social Network Analysis (SNA) has evolved as a popular, standard method for modeling meaningful, often hidden structural relationships in communities. Existing SNA tools often involve extensive pre-processing or intensive programming skills that can challenge practitioners and students alike. NodeXL, an open-source template for Microsoft Excel, integrates a library of common network metrics and graph layout algorithms within the familiar spreadsheet format, offering a potentially low-barrier-to-entry framework for teaching and learning SNA. We present the preliminary findings of 2 user studies of 21 graduate students who engaged in SNA using NodeXL. The majority of students, while information professionals, had little technical background or experience with SNA techniques. Six of the participants had more technical backgrounds and were chosen specifically for their experience with graph drawing and information visualization. Our primary objectives were (1) to evaluate NodeXL as an SNA tool for a broad base of users and (2) to explore methods for teaching SNA. Our complementary dual case-study format demonstrates the usability of NodeXL for a diverse set of users, and significantly, the power of a tightly integrated metrics/visualization tool to spark insight and facilitate sense-making for students of SNA. %B International Conference on Computational Science and Engineering, 2009. CSE '09 %I IEEE %V 4 %P 332 - 339 %8 2009/08/29/31 %@ 978-1-4244-5334-4 %G eng %R 10.1109/CSE.2009.120 %0 Conference Paper %B IEEE International Conference on Bioinformatics and Biomedicine, 2009. BIBM '09 %D 2009 %T Inexact Local Alignment Search over Suffix Arrays %A Ghodsi,M. %A Pop, Mihai %K bacteria %K Bioinformatics %K biology computing %K Computational Biology %K Costs %K DNA %K DNA homology searches %K DNA sequences %K Educational institutions %K generalized heuristic %K genes %K Genetics %K genome alignment %K Genomics %K human %K inexact local alignment search %K inexact seeds %K local alignment %K local alignment tools %K memory efficient suffix array %K microorganisms %K molecular biophysics %K mouse %K Organisms %K Sensitivity and Specificity %K sequences %K suffix array %K USA Councils %X We describe an algorithm for finding approximate seeds for DNA homology searches. In contrast to previous algorithms that use exact or spaced seeds, our approximate seeds may contain insertions and deletions. We present a generalized heuristic for finding such seeds efficiently and prove that the heuristic does not affect sensitivity. We show how to adapt this algorithm to work over the memory efficient suffix array with provably minimal overhead in running time. We demonstrate the effectiveness of our algorithm on two tasks: whole genome alignment of bacteria and alignment of the DNA sequences of 177 genes that are orthologous in human and mouse. We show our algorithm achieves better sensitivity and uses less memory than other commonly used local alignment tools. %B IEEE International Conference on Bioinformatics and Biomedicine, 2009. BIBM '09 %I IEEE %P 83 - 87 %8 2009/11/01/4 %@ 978-0-7695-3885-3 %G eng %R 10.1109/BIBM.2009.25 %0 Conference Paper %B IEEE International Conference on Systems, Man and Cybernetics, 2009. SMC 2009 %D 2009 %T Replication and automation of expert judgments: Information engineering in legal e-discovery %A Hedin,B. %A Oard, Douglas %K authorisation %K authority control %K Automation %K civil litigation %K CYBERNETICS %K Delay %K digital evidence retrieval %K discovery request %K Educational institutions %K expert judgment automation %K Human computer interaction %K Human-machine cooperation and systems %K human-system task modeling %K information engineering %K Information retrieval %K interactive task %K Law %K law administration %K legal e-discovery %K Legal factors %K PROBES %K Production %K Protocols %K search effort %K Search methods %K text analysis %K text retrieval conference legal track %K United States %K USA Councils %K User modeling %X The retrieval of digital evidence responsive to discovery requests in civil litigation, known in the United States as ¿e-discovery,¿ presents several important and understudied conditions and challenges. Among the most important of these are (i) that the definition of responsiveness that governs the search effort can be learned and made explicit through effective interaction with the responding party, (ii) that the governing definition of responsiveness is generally complex, deriving both from considerations of subject-matter relevance and from considerations of litigation strategy, and (iii) that the result of the search effort is a set (rather than a ranked list) of documents, and sometimes a quite large set, that is turned over to the requesting party and that the responding party certifies to be an accurate and complete response to the request. This paper describes the design of an ¿interactive task¿ for the text retrieval conference's legal track that had the evaluation of the effectiveness of e-discovery applications at the ¿responsive review¿ task as its goal. Notable features of the 2008 interactive task were high-fidelity human-system task modeling, authority control for the definition of ¿responsiveness,¿ and relatively deep sampling for estimation of type 1 and type 2 errors (expressed as ¿precision¿ and ¿recall¿). The paper presents a critical assessment of the strengths and weaknesses of the evaluation design from the perspectives of reliability, reusability, and cost-benefit tradeoffs. %B IEEE International Conference on Systems, Man and Cybernetics, 2009. SMC 2009 %I IEEE %P 102 - 107 %8 2009/10/11/14 %@ 978-1-4244-2793-2 %G eng %R 10.1109/ICSMC.2009.5346118 %0 Conference Paper %B IEEE/WIC/ACM International Joint Conferences on Web Intelligence and Intelligent Agent Technologies, 2009. WI-IAT '09 %D 2009 %T Rigorous Probabilistic Trust-Inference with Applications to Clustering %A DuBois,Thomas %A Golbeck,Jennifer %A Srinivasan, Aravind %K Clustering algorithms %K Conferences %K Educational institutions %K Extraterrestrial measurements %K Inference algorithms %K Intelligent agent %K random graphs %K Social network services %K trust inferrence %K Visualization %K Voting %K Web sites %X The World Wide Web has transformed into an environment where users both produce and consume information. In order to judge the validity of information, it is important to know how trustworthy its creator is. Since no individual can have direct knowledge of more than a small fraction of information authors, methods for inferring trust are needed. We propose a new trust inference scheme based on the idea that a trust network can be viewed as a random graph, and a chain of trust as a path in that graph. In addition to having an intuitive interpretation, our algorithm has several advantages, noteworthy among which is the creation of an inferred trust-metric space where the shorter the distance between two people, the higher their trust. Metric spaces have rigorous algorithms for clustering, visualization, and related problems, any of which is directly applicable to our results. %B IEEE/WIC/ACM International Joint Conferences on Web Intelligence and Intelligent Agent Technologies, 2009. WI-IAT '09 %I IEEE %V 1 %P 655 - 658 %8 2009/09/15/18 %@ 978-0-7695-3801-3 %G eng %R 10.1109/WI-IAT.2009.109 %0 Conference Paper %B International Symposium on Collaborative Technologies and Systems, 2009. CTS '09 %D 2009 %T Understanding social computing participation with visual exploration tools %A Shneiderman, Ben %K Application software %K Books %K Collaborative tools %K Computer science %K Data visualization %K Educational institutions %K History %K International collaboration %K Social network services %K Sociotechnical systems %X The rapid growth of socio-technical systems, social media and social networking websites has raised the importance of understanding the determinants of their success. The pressure to understand success is increased by the shift from playful discretionary applications to mission critical applications in government, business, and civic settings. These include homeland defense, energy sustainability, environmental conservation, disaster response, and community safety. Information visualization tools and statistical methods can both be helpful, but their utility grows when they are well-integrated. This talk will demonstrate novel tools for network evolution and offer a framework for thinking about motivating technology-mediated social participation. %B International Symposium on Collaborative Technologies and Systems, 2009. CTS '09 %I IEEE %P xi-xii - xi-xii %8 2009/05/18/22 %@ 978-1-4244-4584-4 %G eng %R 10.1109/CTS.2009.5067426 %0 Conference Paper %B IEEE 25th International Conference on Data Engineering, 2009. ICDE '09 %D 2009 %T Web Monitoring 2.0: Crossing Streams to Satisfy Complex Data Needs %A Roitman,H. %A Gal,A. %A Raschid, Louiqa %K Bandwidth %K complex client information need %K Data Delivery %K Data engineering %K database management systems %K Educational institutions %K Internet %K Mashups %K mashups generation %K Monitoring %K multiple information source %K offline algorithmic solution %K Portals %K PROBES %K Profiles %K Query processing %K scalability %K scheduling %K volatile information stream %K Web 2.0 %K Web Monitoring %X Web monitoring 2.0 supports the complex information needs of clients who probe multiple information sources and generate mashups by integrating across these volatile streams. A proxy that aims at satisfying multiple customized client profiles will face a scalability challenge in trying to maximize the number of clients served while at the same time fully satisfying complex client needs. In this paper, we introduce an abstraction of complex execution intervals, a combination of time intervals and information streams, to capture complex client needs. Given some budgetary constraints (e.g., bandwidth), we present offline algorithmic solutions for the problem of maximizing completeness of capturing complex profiles. %B IEEE 25th International Conference on Data Engineering, 2009. ICDE '09 %I IEEE %P 1215 - 1218 %8 2009/04/29/March %@ 978-1-4244-3422-0 %G eng %R 10.1109/ICDE.2009.204 %0 Conference Paper %B IEEE INFOCOM 2008. The 27th Conference on Computer Communications %D 2008 %T Capacity of Asynchronous Random-Access Scheduling in Wireless Networks %A Chafekar,D. %A Levin,D. %A Kumar,V. S.A %A Marathe,M. V %A Parthasarathy,S. %A Srinivasan, Aravind %K asynchronous random-access scheduling %K channel access probability %K Computer networks %K Computer science %K Educational institutions %K Interference %K Optimal scheduling %K Peer to peer computing %K probability %K Processor scheduling %K radio link %K radio links %K radio networks %K Routing %K scheduling %K Throughput %K throughput capacity %K wireless channels %K Wireless networks %X We study the throughput capacity of wireless networks which employ (asynchronous) random-access scheduling as opposed to deterministic scheduling. The central question we answer is: how should we set the channel-access probability for each link in the network so that the network operates close to its optimal throughput capacity? We design simple and distributed channel-access strategies for random-access networks which are provably competitive with respect to the optimal scheduling strategy, which is deterministic, centralized, and computationally infeasible. We show that the competitiveness of our strategies are nearly the best achievable via random-access scheduling, thus establishing fundamental limits on the performance of random- access. A notable outcome of our work is that random access compares well with deterministic scheduling when link transmission durations differ by small factors, and much worse otherwise. The distinguishing aspects of our work include modeling and rigorous analysis of asynchronous communication, asymmetry in link transmission durations, and hidden terminals under arbitrary link-conflict based wireless interference models. %B IEEE INFOCOM 2008. The 27th Conference on Computer Communications %I IEEE %P 1148 - 1156 %8 2008/04/13/18 %@ 978-1-4244-2025-4 %G eng %R 10.1109/INFOCOM.2008.170 %0 Conference Paper %B IEEE 24th International Conference on Data Engineering, 2008. ICDE 2008 %D 2008 %T Flow Algorithms for Parallel Query Optimization %A Deshpande, Amol %A Hellerstein,L. %K Casting %K computational complexity %K Cost function %K Databases %K Delay %K distributed environment %K Educational institutions %K flow maximization algorithm %K Interleaved codes %K interoperator parallelism %K minimisation %K multiway join query response time minimization problem %K parallel database %K Parallel databases %K parallel query optimization %K Partitioning algorithms %K pipeline processing %K pipelined parallelism %K polynomial-time algorithm %K query planning problem %K Query processing %K Web service %K Web services %X We address the problem of minimizing the response time of a multi-way join query using pipelined (inter-operator) parallelism, in a parallel or a distributed environment. We observe that in order to fully exploit the parallelism in the system, we must consider a new class of ";interleaving"; plans, where multiple query plans are used simultaneously to minimize the response time of a query (or to maximize the tuple-throughput of the system). We cast the query planning problem in this environment as a ";flow maximization problem";, and present polynomial-time algorithms that (statically) find the optimal set of plans to use for a given query, for a large class of multi-way join queries. Our proposed algorithms also naturally extend to query optimization over web services. Finally we present an extensive experimental evaluation that demonstrates both the need to consider such plans in parallel query processing and the effectiveness of our algorithms. %B IEEE 24th International Conference on Data Engineering, 2008. ICDE 2008 %I IEEE %P 754 - 763 %8 2008/04/07/12 %@ 978-1-4244-1836-7 %G eng %R 10.1109/ICDE.2008.4497484 %0 Conference Paper %B IEEE International Conference on Acoustics, Speech and Signal Processing, 2008. ICASSP 2008 %D 2008 %T Imaging concert hall acoustics using visual and audio cameras %A O'Donovan,A. %A Duraiswami, Ramani %A Zotkin,Dmitry N %K Acoustic imaging %K acoustic intensity images %K acoustic measurement %K Acoustic measurements %K Acoustic scattering %K acoustic signal processing %K acoustical camera %K acoustical scene analysis %K acquired audio registration %K audio cameras %K audio signal processing %K CAMERAS %K central projection %K Computer vision %K Educational institutions %K HUMANS %K image registration %K Image segmentation %K imaging concert hall acoustics %K Layout %K microphone arrays %K panoramic mosaiced visual image %K Raman scattering %K reverberation %K room acoustics %K spherical microphone array beamformer %K spherical microphone arrays %K video image registration %K visual cameras %X Using a developed real time audio camera, that uses the output of a spherical microphone array beamformer steered in all directions to create central projection to create acoustic intensity images, we present a technique to measure the acoustics of rooms and halls. A panoramic mosaiced visual image of the space is also create. Since both the visual and the audio camera images are central projection, registration of the acquired audio and video images can be performed using standard computer vision techniques. We describe the technique, and apply it to the examine the relation between acoustical features and architectural details of the Dekelbaum concert hall at the Clarice Smith Performing Arts Center in College Park, MD. %B IEEE International Conference on Acoustics, Speech and Signal Processing, 2008. ICASSP 2008 %I IEEE %P 5284 - 5287 %8 2008/// %@ 978-1-4244-1483-3 %G eng %R 10.1109/ICASSP.2008.4518852 %0 Conference Paper %B 5th Annual IEEE Communications Society Conference on Sensor, Mesh and Ad Hoc Communications and Networks, 2008. SECON '08 %D 2008 %T Immunity-Based Epidemic Routing in Intermittent Networks %A Mundur, Padma %A Seligman,M. %A Jin Na Lee %K Analytical models %K Delay %K delivered messages %K Disruption tolerant networking %K Educational institutions %K immunity-based epidemic routing %K information dissemination %K intermittent networks %K Mobile ad hoc networks %K Network topology %K Performance analysis %K Resource management %K resource utilization %K routing protocol %K routing protocols %K telecommunication network topology %X In this research, we propose to modify and extend epidemic routing used in intermittent networks. In particular, we propose to include immunity-based information disseminated in the reverse once messages get delivered to their destination. The goal is to design a more efficient routing protocol in terms of resource utilization. The idea is to analyze and evaluate the network performance using an immunity scheme in the context of epidemic routing and its variants. The reverse dissemination of such information requires minimal resources and the tradeoff in timely purging of delivered messages can be significant. We are using ns2 to implement a detailed simulation of the proposed immunity-based epidemic routing. %B 5th Annual IEEE Communications Society Conference on Sensor, Mesh and Ad Hoc Communications and Networks, 2008. SECON '08 %I IEEE %P 609 - 611 %8 2008/06/16/20 %@ 978-1-4244-1777-3 %G eng %R 10.1109/SAHCN.2008.86 %0 Conference Paper %B IEEE International Conference on Acoustics, Speech and Signal Processing, 2008. ICASSP 2008 %D 2008 %T Measuring 1st order stretchwith a single filter %A Bitsakos,K. %A Domke, J. %A Fermüller, Cornelia %A Aloimonos, J. %K Cepstral analysis %K Educational institutions %K filter %K filtering theory %K Fourier transforms %K Frequency domain analysis %K Frequency estimation %K Gabor filters %K Image analysis %K IMAGE PROCESSING %K linear stretch measurement %K local signal transformation measurement %K Nonlinear filters %K Phase estimation %K Signal analysis %K Speech processing %X We analytically develop a filter that is able to measure the linear stretch of the transformation around a point, and present results of applying it to real signals. We show that this method is a real-time alternative solution for measuring local signal transformations. Experimentally, this method can accurately measure stretch, however, it is sensitive to shift. %B IEEE International Conference on Acoustics, Speech and Signal Processing, 2008. ICASSP 2008 %I IEEE %P 909 - 912 %8 2008/04/31/March %@ 978-1-4244-1483-3 %G eng %R 10.1109/ICASSP.2008.4517758 %0 Conference Paper %B Seventh IEEE International Conference on Data Mining Workshops, 2007. ICDM Workshops 2007 %D 2007 %T Representing Tuple and Attribute Uncertainty in Probabilistic Databases %A Sen,P. %A Deshpande, Amol %A Getoor, Lise %K attribute uncertainty %K Computer science %K Conferences %K correlation structures %K data mining %K Data models %K database management systems %K Educational institutions %K inference mechanisms %K noisy data sources %K probabilistic database %K probabilistic inference %K Probability distribution %K Query processing %K Relational databases %K Sensor phenomena and characterization %K tuple representation %K Uncertainty %K uncertainty handling %X There has been a recent surge in work in probabilistic databases, propelled in large part by the huge increase in noisy data sources-sensor data, experimental data, data from uncurated sources, and many others. There is a growing need to be able to flexibly represent the uncertainties in the data, and to efficiently query the data. Building on existing probabilistic database work, we present a unifying framework which allows a flexible representation of correlated tuple and attribute level uncertainties. An important capability of our representation is the ability to represent shared correlation structures in the data. We provide motivating examples to illustrate when such shared correlation structures are likely to exist. Representing shared correlations structures allows the use of sophisticated inference techniques based on lifted probabilistic inference that, in turn, allows us to achieve significant speedups while computing probabilities for results of user-submitted queries. %B Seventh IEEE International Conference on Data Mining Workshops, 2007. ICDM Workshops 2007 %I IEEE %P 507 - 512 %8 2007/10/28/31 %@ 978-0-7695-3019-2 %G eng %R 10.1109/ICDMW.2007.11 %0 Conference Paper %B IEEE Military Communications Conference, 2007. MILCOM 2007 %D 2007 %T Verified Enforcement of Security Policies for Cross-Domain Information Flows %A Swamy,Nikhil %A Hicks, Michael W. %A Tsang,Simon %K Collaboration %K Computer languages %K Data security %K Educational institutions %K Government %K Information analysis %K Information filtering %K Information filters %K Information security %K Vehicles %X We describe work in progress that uses program analysis to show that security-critical programs, such as cross-domain guards, correctly enforce cross-domain security policies. We are enhancing existing techniques from the field of Security-oriented Programming Languages to construct a new language for the construction of secure networked applications, SELINKS. In order to specify and enforce expressive and fine-grained policies, we advocate dynamically associating security labels with sensitive entities. Programs written in SELINKS are statically guaranteed to correctly manipulate an entity's security labels and to ensure that the appropriate policy checks mediate all operations that are performed on the entity. We discuss the design of our main case study : a web-based Collaborative Planning Application that will permit a collection of users, with varying security requirements and clearances, to access sensitive data sources and collaboratively create documents based on these sources. %B IEEE Military Communications Conference, 2007. MILCOM 2007 %I IEEE %P 1 - 7 %8 2007/10/29/31 %@ 978-1-4244-1513-7 %G eng %R 10.1109/MILCOM.2007.4455189 %0 Conference Paper %B 2006 IEEE International Conference on Acoustics, Speech and Signal Processing, 2006. ICASSP 2006 Proceedings %D 2006 %T Frequency Independent Flexible Spherical Beamforming Via Rbf Fitting %A Yerukhimovich,A. %A Duraiswami, Ramani %A Gumerov, Nail A. %A Zotkin,Dmitry N %K acoustic signal processing %K array signal processing %K band-limited radial basis functions %K Computer science %K Educational institutions %K Eigenvalues and eigenfunctions %K Equations %K Frequency %K frequency independent beamformer weights %K frequency independent flexible spherical beamforming %K microphone arrays %K Nails %K Position measurement %K RBF fitting %K Robustness %K sound analysis %K spherical array data %K spherical microphone array %X We describe a new method for sound analysis using a spherical microphone array without the use of quadrature over the sphere. Quadrature based solutions are very sensitive to the placement of microphones on the sphere, needing measurements to be made at exactly the quadrature positions. We propose to use fitting with band-limited radial basis functions (RBFs) rather than quadrature. Our approach results in frequency independent beamformer weights for flexibly placed microphone locations. Results are demonstrated using both synthetic and real spherical array data %B 2006 IEEE International Conference on Acoustics, Speech and Signal Processing, 2006. ICASSP 2006 Proceedings %I IEEE %V 5 %P V-V - V-V %8 2006/05// %@ 1-4244-0469-X %G eng %R 10.1109/ICASSP.2006.1661208 %0 Conference Paper %B 19th IEEE Computer Security Foundations Workshop, 2006 %D 2006 %T Managing policy updates in security-typed languages %A Swamy,N. %A Hicks, Michael W. %A Tse,S. %A Zdancewic,S. %K Access control %K Computer languages %K Data security %K Database systems %K dynamic queries %K dynamic semantics %K Educational institutions %K high level languages %K Information security %K information-flow policy management %K Lattices %K Network servers %K Operating systems %K policy update management %K Robustness %K role-based security policies %K RT role-based trust-management framework %K Rx security-typed programming language %K security of data %K statically verified transactions %K transitive flows %X This paper presents Rx, a new security-typed programming language with features intended to make the management of information-flow policies more practical. Security labels in Rx, in contrast to prior approaches, are defined in terms of owned roles, as found in the RT role-based trust-management framework. Role-based security policies allow flexible delegation, and our language Rx provides constructs through which programs can robustly update policies and react to policy updates dynamically. Our dynamic semantics use statically verified transactions to eliminate illegal information flows across updates, which we call transitive flows. Because policy updates can be observed through dynamic queries, policy updates can potentially reveal sensitive information. As such, Rx considers policy statements themselves to be potentially confidential information and subject to information-flow metapolicies %B 19th IEEE Computer Security Foundations Workshop, 2006 %I IEEE %P 13 pp.-216 - 13 pp.-216 %8 2006/// %@ 0-7695-2615-2 %G eng %R 10.1109/CSFW.2006.17 %0 Conference Paper %B 2006 International Conference on Parallel Processing Workshops, 2006. ICPP 2006 Workshops %D 2006 %T Model-based OpenMP implementation of a 3D facial pose tracking system %A Saha,S. %A Chung-Ching Shen %A Chia-Jui Hsu %A Aggarwal,G. %A Veeraraghavan,A. %A Sussman, Alan %A Bhattacharyya, Shuvra S. %K 3D facial pose tracking system %K application modeling %K application program interfaces %K application scheduling %K coarse-grain dataflow graphs %K Concurrent computing %K data flow graphs %K Educational institutions %K face recognition %K IMAGE PROCESSING %K image processing applications %K Inference algorithms %K Message passing %K OpenMP platform %K parallel implementation %K PARALLEL PROCESSING %K parallel programming %K Particle tracking %K Processor scheduling %K SHAPE %K shared memory systems %K shared-memory systems %K Solid modeling %K tracking %X Most image processing applications are characterized by computation-intensive operations, and high memory and performance requirements. Parallelized implementation on shared-memory systems offer an attractive solution to this class of applications. However, we cannot thoroughly exploit the advantages of such architectures without proper modeling and analysis of the application. In this paper, we describe our implementation of a 3D facial pose tracking system using the OpenMP platform. Our implementation is based on a design methodology that uses coarse-grain dataflow graphs to model and schedule the application. We present our modeling approach, details of the implementation that we derived based on this modeling approach, and associated performance results. The parallelized implementation achieves significant speedup, and meets or exceeds the target frame rate under various configurations %B 2006 International Conference on Parallel Processing Workshops, 2006. ICPP 2006 Workshops %I IEEE %P 8 pp.-73 - 8 pp.-73 %8 2006/// %@ 0-7695-2637-3 %G eng %R 10.1109/ICPPW.2006.55 %0 Conference Paper %B 2006 IEEE Computer Society Conference on Computer Vision and Pattern Recognition %D 2006 %T A Projective Invariant for Textures %A Yong Xu %A Hui Ji %A Fermüller, Cornelia %K Computer science %K Computer vision %K Educational institutions %K Fractals %K Geometry %K Image texture %K Level set %K lighting %K Robustness %K Surface texture %X Image texture analysis has received a lot of attention in the past years. Researchers have developed many texture signatures based on texture measurements, for the purpose of uniquely characterizing the texture. Existing texture signatures, in general, are not invariant to 3D transforms such as view-point changes and non-rigid deformations of the texture surface, which is a serious limitation for many applications. In this paper, we introduce a new texture signature, called the multifractal spectrum (MFS). It provides an efficient framework combining global spatial invariance and local robust measurements. The MFS is invariant under the bi-Lipschitz map, which includes view-point changes and non-rigid deformations of the texture surface, as well as local affine illumination changes. Experiments demonstrate that the MFS captures the essential structure of textures with quite low dimension. %B 2006 IEEE Computer Society Conference on Computer Vision and Pattern Recognition %I IEEE %V 2 %P 1932 - 1939 %8 2006/// %@ 0-7695-2597-0 %G eng %R 10.1109/CVPR.2006.38 %0 Conference Paper %B 2006 6th IEEE-RAS International Conference on Humanoid Robots %D 2006 %T A Sensory-Motor Language for Human Activity Understanding %A Guerra-Filho,G. %A Aloimonos, J. %K Actuators %K associative learning %K atomic segments %K computational linguistics %K Computer science %K Computer vision %K Educational institutions %K grammars %K human activity language %K human activity understanding %K human movement syntax %K Humanoid robots %K HUMANS %K joint angles %K kinetemes %K kinetological system %K Laboratories %K learning (artificial intelligence) %K List key index terms here %K Morphology %K motor information %K No mare than 5 %K parallel learning %K Reproducibility of results %K Robot kinematics %K Robot programming %K robot vision %K sensory-motor language %K sequential language learning %K symbolic nonarbitrary representation %K visual information %X We have empirically discovered that the space of human actions has a linguistic framework. This is a sensory-motor space consisting of the evolution of the joint angles of the human body in movement. The space of human activity has its own phonemes, morphemes, and sentences. We present a human activity language (HAL) for symbolic non-arbitrary representation of visual and motor information. In phonology, we define atomic segments (kinetemes) that are used to compose human activity. We introduce the concept of a kinetological system and propose five basic properties for such a system: compactness, view-invariance, reproducibility, selectivity, and reconstructivity. In morphology, we extend sequential language learning to incorporate associative learning with our parallel learning approach. Parallel learning is effective in identifying the kinetemes and active joints in a particular action. In syntax, we suggest four lexical categories for our human activity language (noun, verb, adjective, and adverb). These categories are combined into sentences through syntax for human movement %B 2006 6th IEEE-RAS International Conference on Humanoid Robots %I IEEE %P 69 - 75 %8 2006/12/04/6 %@ 1-4244-0200-X %G eng %R 10.1109/ICHR.2006.321365 %0 Conference Paper %B Computer Software and Applications Conference, 2006. COMPSAC '06. 30th Annual International %D 2006 %T A Software Architectural Approach to Security by Design %A Ray,A. %A Cleaveland, Rance %K architecture description notation %K Clocks %K communication semantics %K Computer architecture %K computer crime %K computer security %K Connectors %K Costs %K Degradation %K Delay %K Educational institutions %K security design %K security of data %K Software architecture %K software engineering %X This paper shows how an architecture description notation that has support for timed events can be used to provide a meta-language for specifying exact communication semantics. The advantages of such an approach is that a designer is made fully aware of the ramifications of her design choices so that an attacker can no longer take advantage of hidden assumptions %B Computer Software and Applications Conference, 2006. COMPSAC '06. 30th Annual International %I IEEE %V 2 %P 83 - 86 %8 2006/09/17/21 %@ 0-7695-2655-1 %G eng %R 10.1109/COMPSAC.2006.102 %0 Conference Paper %B Parallel and Distributed Processing Symposium, 2005. Proceedings. 19th IEEE International %D 2005 %T Comparing the Performance of High-Level Middleware Systems in Shared and Distributed Memory Parallel Environments %A Kim,Jik-Soo %A Andrade,H. %A Sussman, Alan %K Application software %K Computer science %K Computer vision %K Data analysis %K Distributed computing %K distributed computing environment %K distributed memory parallel environment %K distributed shared memory systems %K Educational institutions %K high-level middleware system %K I/O-intensive data analysis application %K Libraries %K Middleware %K parallel computing environment %K parallel library support %K parallel memories %K programming language %K programming languages %K Runtime environment %K shared memory parallel environment %K Writing %X The utilization of toolkits for writing parallel and/or distributed applications has been shown to greatly enhance developer's productivity. Such an approach hides many of the complexities associated with writing these applications, rather than relying solely on programming language aids and parallel library support, such as MPI or PVM. In this work, we evaluate three different middleware systems that have been used to implement a computation and I/O-intensive data analysis application from the domain of computer vision. This study shows the benefits and overheads associated with each of the middleware systems, in different homogeneous computational environments and with different workloads. Our results lead the way toward being able to make better decisions for tuning the application environment, for selecting the appropriate middleware, and also for designing more powerful middleware systems to efficiently build and run highly complex applications in both parallel and distributed computing environments. %B Parallel and Distributed Processing Symposium, 2005. Proceedings. 19th IEEE International %I IEEE %P 30 - 30 %8 2005/04// %@ 0-7695-2312-9 %G eng %R 10.1109/IPDPS.2005.144 %0 Conference Paper %B Parallel and Distributed Processing Symposium, 2005. Proceedings. 19th IEEE International %D 2005 %T High Performance Communication between Parallel Programs %A Jae-Yong Lee %A Sussman, Alan %K Adaptive arrays %K Analytical models %K Chaotic communication %K Computational modeling %K Computer science %K Data analysis %K data distribution %K Educational institutions %K high performance communication %K image data analysis %K image resolution %K inter-program communication patterns %K InterComm %K Libraries %K Message passing %K parallel languages %K parallel libraries %K parallel programming %K parallel programs %K performance evaluation %K Wind %X 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. %B Parallel and Distributed Processing Symposium, 2005. Proceedings. 19th IEEE International %I IEEE %P 177b- 177b - 177b- 177b %8 2005/04// %@ 0-7695-2312-9 %G eng %R 10.1109/IPDPS.2005.243 %0 Conference Paper %B 12th International Conference on Advanced Robotics, 2005. ICAR '05. Proceedings %D 2005 %T Identifying and segmenting human-motion for mobile robot navigation using alignment errors %A Abd-Almageed, Wael %A Burns,B. J %A Davis, Larry S. %K Computer errors %K Educational institutions %K Frequency estimation %K human-motion identification %K human-motion segmentation %K HUMANS %K Image motion analysis %K Image segmentation %K mobile robot navigation %K Mobile robots %K Motion estimation %K Navigation %K Object detection %K robot vision %K SHAPE %X This paper presents a new human-motion identification and segmentation algorithm, for mobile robot platforms. The algorithm is based on computing the alignment error between pairs of object images acquired from a moving platform. Pairs of images generating relatively small alignment errors are used to estimate the fundamental frequency of the object's motion. A decision criterion is then used to test the significance of the estimated frequency and to classify the object's motion. To verify the validity of the proposed approach, experimental results are shown on different classes of objects %B 12th International Conference on Advanced Robotics, 2005. ICAR '05. Proceedings %I IEEE %P 398 - 403 %8 2005/07// %@ 0-7803-9178-0 %G eng %R 10.1109/ICAR.2005.1507441 %0 Conference Paper %B IEEE Computer Society Conference on Computer Vision and Pattern Recognition, 2005. CVPR 2005 %D 2005 %T Integration of motion fields through shape %A Ji,H. %A Fermüller, Cornelia %K 3D motion estimation %K Automation %K CAMERAS %K computational geometry %K Computer vision %K constrained minimization problem %K decoupling translation from rotation %K Educational institutions %K image colour analysis %K image gradients %K image resolution %K Image segmentation %K image sequence %K Image sequences %K integration of motion fields %K Layout %K minimisation %K Motion estimation %K motion field integration %K motion segmentation %K parameter estimation %K planar patches %K rank-3 constraint %K scene patches %K SHAPE %K shape and rotation %K shape estimation %K structure estimation %X Structure from motion from single flow fields has been studied intensively, but the integration of information from multiple flow fields has not received much attention. Here we address this problem by enforcing constraints on the shape (surface normals) of the scene in view, as opposed to constraints on the structure (depth). The advantage of integrating shape is two-fold. First, we do not need to estimate feature correspondences over multiple frames, but we only need to match patches. Second, the shape vectors in the different views are related only by rotation. This constraint on shape can be combined easily with motion estimation, thus formulating motion and structure estimation from multiple views as a practical constrained minimization problem using a rank-3 constraint. Based on this constraint, we develop a 3D motion technique, which locates through color and motion segmentation, planar patches in the scene, matches patches over multiple frames, and estimates the motion between multiple frames and the shape of the selected scene patches using the image gradients. Experiments evaluate the accuracy of the 3D motion estimation and demonstrate the motion and shape estimation of the technique by super-resolving an image sequence. %B IEEE Computer Society Conference on Computer Vision and Pattern Recognition, 2005. CVPR 2005 %I IEEE %V 2 %P 663- 669 vol. 2 - 663- 669 vol. 2 %8 2005/06/20/25 %@ 0-7695-2372-2 %G eng %R 10.1109/CVPR.2005.190 %0 Conference Paper %B Proceedings of the 5th ACM/IEEE-CS Joint Conference on Digital Libraries, 2005. JCDL '05 %D 2005 %T Meaningful presentations of photo libraries: rationale and applications of bi-level radial quantum layouts %A Kustanowitz,J. %A Shneiderman, Ben %K 1024 pixel %K 1200 pixel %K 1280 pixel %K 1310720 pixel %K 1600 pixel %K 1920000 pixel %K Application software %K bi-level radial quantum layouts %K Computer displays %K Computer science %K digital libraries %K Educational institutions %K Image retrieval %K Layout %K layout generation %K Lifting equipment %K linear strips %K Permission %K photo layouts %K photo library searching %K photo management %K Photography %K Quantum computing %K software libraries %K Strips %K two-dimensional grid %K User interfaces %K visual databases %K visual presentation %K zoomable three dimensional arrangements %X Searching photo libraries can be made more satisfying and successful if search results are presented in a way that allows users to gain an overview of the photo categories. Since photo layouts on computer displays are the primary way that users get an overview, we propose a novel approach to show more photos in meaningful groupings. Photo layouts can be linear strips, or zoomable three dimensional arrangements, but the most common form is the two-dimensional grid. This paper introduces a novel bi-level hierarchical layout with motivating examples. In a bilevel hierarchy, one region is designated for primary content - an image, text, or combination. Adjacent to that region, groups of photos are placed radially in an ordered fashion, such that the relationship of the single primary region to its many secondary regions is apparent. A compelling aspect is the interactive experience in which the layout is dynamically resized, allowing users to rapidly, incrementally, and reversibly alter the dimensions and content. It can accommodate hundreds of photos in dozens of regions, can be customized in a corner or center layout, and can scale from an element on a web page to a large poster size. On typical displays (1024 times 1280 or 1200 times 1600 pixels), bi-level radial quantum layouts can conveniently accommodate 2-20 regions with tens or hundreds of photos per region %B Proceedings of the 5th ACM/IEEE-CS Joint Conference on Digital Libraries, 2005. JCDL '05 %I IEEE %P 188 - 196 %8 2005/06/07/11 %@ 1-58113-876-8 %G eng %R 10.1145/1065385.1065431 %0 Conference Paper %B IEEE Workshop on Applications of Signal Processing to Audio and Acoustics, 2005 %D 2005 %T Plane-wave decomposition analysis for spherical microphone arrays %A Duraiswami, Ramani %A Zhiyun Li %A Zotkin,Dmitry N %A Grassi,E. %A Gumerov, Nail A. %K Acoustic propagation %K Acoustic scattering %K acoustic signal processing %K acoustic waves %K array signal processing %K band-limit criteria %K beamforming %K Educational institutions %K Fourier transforms %K Frequency %K Laboratories %K microphone arrays %K Nails %K Nyquist criterion %K Nyquist-like criterion %K Partial differential equations %K plane-wave decomposition analysis %K sound field analysis %K spherical microphone arrays %K spherical wave-functions %X 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. %B IEEE Workshop on Applications of Signal Processing to Audio and Acoustics, 2005 %I IEEE %P 150 - 153 %8 2005/10// %@ 0-7803-9154-3 %G eng %R 10.1109/ASPAA.2005.1540191 %0 Conference Paper %B Proceedings of the 2005 IEEE International Conference on Robotics and Automation, 2005. ICRA 2005 %D 2005 %T Robust Contrast Invariant Stereo Correspondence %A Ogale, A. S %A Aloimonos, J. %K Apertures %K Calibration %K CAMERAS %K Computer science %K contrast invariance %K diffusion %K Educational institutions %K Frequency %K gabor %K Hardware %K occlusions %K Robot vision systems %K Robotics and automation %K Robustness %K stereo %X A stereo pair of cameras attached to a robot will inevitably yield images with different contrast. Even if we assume that the camera hardware is identical, due to slightly different points of view, the amount of light entering the two cameras is also different, causing dynamically adjusted internal parameters such as aperture, exposure and gain to be different. Due to the difficulty of obtaining and maintaining precise intensity or color calibration between the two cameras, contrast invariance becomes an extremely desirable property of stereo correspondence algorithms. The problem of achieving point correspondence between a stereo pair of images is often addressed by using the intensity or color differences as a local matching metric, which is sensitive to contrast changes. We present an algorithm for contrast invariant stereo matching which relies on multiple spatial frequency channels for local matching. A fast global framework uses the local matching to compute the correspondences and find the occlusions. We demonstrate that the use of multiple frequency channels allows the algorithm to yield good results even in the presence of significant amounts of noise. %B Proceedings of the 2005 IEEE International Conference on Robotics and Automation, 2005. ICRA 2005 %I IEEE %P 819 - 824 %8 2005/04/18/22 %@ 0-7803-8914-X %G eng %R 10.1109/ROBOT.2005.1570218 %0 Conference Paper %B IEEE International Symposium on Cluster Computing and the Grid, 2005. CCGrid 2005 %D 2005 %T Spatial indexing of distributed multidimensional datasets %A Nam,B. %A Sussman, Alan %K centralized global index algorithm %K centralized index server %K Computer science %K database indexing %K distributed databases %K distributed multidimensional dataset %K Educational institutions %K File servers %K Indexing %K Large-scale systems %K Multidimensional systems %K Network servers %K replication protocol %K replication techniques %K scalability %K Sensor systems %K spatial data structures %K spatial indexing %K two-level hierarchical index algorithm %K wide area networks %X While declustering methods for distributed multidimensional indexing of large datasets have been researched widely in the past, replication techniques for multidimensional indexes have not been investigated deeply. In general, a centralized index server may become the performance bottleneck in a wide area network rather than the data servers, since the index is likely to be accessed more often than any of the datasets in the servers. In this paper, we present two different multidimensional indexing algorithms for a distributed environment - a centralized global index and a two-level hierarchical index. Our experimental results show that the centralized scheme does not scale well for either insertion or searching the index. In order to improve the scalability of the index server, we have employed a replication protocol for both the centralized and two-level index schemes that allows some inconsistency between replicas without affecting correctness. Our experiments show that the two-level hierarchical index scheme shows better scalability for both building and searching the index than the non-replicated centralized index, but replication can make the centralized index faster than the two-level hierarchical index for searching in some cases. %B IEEE International Symposium on Cluster Computing and the Grid, 2005. CCGrid 2005 %I IEEE %V 2 %P 743- 750 Vol. 2 - 743- 750 Vol. 2 %8 2005/05/09/12 %@ 0-7803-9074-1 %G eng %R 10.1109/CCGRID.2005.1558637 %0 Conference Paper %B IEEE Symposium on Information Visualization, 2005. INFOVIS 2005 %D 2005 %T Turning information visualization innovations into commercial products: lessons to guide the next success %A Shneiderman, Ben %A Rao,R. %A Andrews,K. %A Ahlberg,C. %A Brodbeck,D. %A Jewitt,T. %A Mackinlay,J. %K Books %K commercial development %K commercial product %K Computer interfaces %K Computer science %K data visualisation %K Data visualization %K Educational institutions %K exploratory data analysis %K information visualization innovation %K information visualization tool %K innovation management %K Laboratories %K Management training %K new technology emergence %K Technological innovation %K technology transfer %K Turning %K User interfaces %X As information visualization matures as an academic research field, commercial spinoffs are proliferating, but success stories are harder to find. This is the normal process of emergence for new technologies, but the panel organizers believe that there are certain strategies that facilitate success. To teach these lessons, we have invited several key figures who are seeking to commercialize information visualization tools. The panelists make short presentations, engage in a moderated discussion, and respond to audience questions. %B IEEE Symposium on Information Visualization, 2005. INFOVIS 2005 %I IEEE %P 241 - 244 %8 2005/10/23/25 %@ 0-7803-9464-X %G eng %R 10.1109/INFVIS.2005.1532153 %0 Conference Paper %B 13th IEEE International Symposium on High performance Distributed Computing, 2004. Proceedings %D 2004 %T Automated cluster-based Web service performance tuning %A Chung,I. -H %A Hollingsworth, Jeffrey K %K Active Harmony system %K automated performance tuning %K business %K cluster-based Web service system %K Clustering algorithms %K Computer science %K Educational institutions %K electronic commerce %K Internet %K Middleware %K performance evaluation %K scalability %K Throughput %K Transaction databases %K Web server %K Web services %K workstation clusters %X Active harmony provides a way to automate performance tuning. We apply the Active Harmony system to improve the performance of a cluster-based web service system. The performance improvement cannot easily be achieved by tuning individual components for such a system. The experimental results show that there is no single configuration for the system that performs well for all kinds of workloads. By tuning the parameters, Active Harmony helps the system adapt to different workloads and improve the performance up to 16%. For scalability, we demonstrate how to reduce the time when tuning a large system with many tunable parameters. Finally an algorithm is proposed to automatically adjust the structure of cluster-based web systems, and the system throughput is improved up to 70% using this technique. %B 13th IEEE International Symposium on High performance Distributed Computing, 2004. Proceedings %I IEEE %P 36 - 44 %8 2004/06/04/6 %@ 0-7695-2175-4 %G eng %R 10.1109/HPDC.2004.1323484 %0 Conference Paper %B Eighth International Conference on Information Visualisation, 2004. IV 2004. Proceedings %D 2004 %T Extending the utility of treemaps with flexible hierarchy %A Chintalapani,G. %A Plaisant, Catherine %A Shneiderman, Ben %K 2D displays %K Computer displays %K Computer science %K data visualisation %K Data visualization %K Educational institutions %K flexible hierarchy %K graphical user interface %K Graphical user interfaces %K hierarchical information %K Nominations and elections %K Switches %K Tree data structures %K Tree graphs %K Treemap 4.0 %K Two dimensional displays %K usability %K visualization technique %X Treemaps are a visualization technique for presenting hierarchical information on two-dimensional displays. Prior implementations limit the visualization to pre-defined static hierarchies. Flexible hierarchy, a new capability of Treemap 4.0, enables users to define various hierarchies through dynamically selecting a series of data attributes so that they can discover patterns, clusters and outliers. This work describes the design and implementation issues of flexible hierarchy. It then reports on a usability study, which led to enhancements to the interface. %B Eighth International Conference on Information Visualisation, 2004. IV 2004. Proceedings %I IEEE %P 335 - 344 %8 2004/07/14/16 %@ 0-7695-2177-0 %G eng %R 10.1109/IV.2004.1320166 %0 Conference Paper %B Eighth International Conference on Information Visualisation, 2004. IV 2004. Proceedings %D 2004 %T Facilitating understanding of information visualizations: emerging principles and examples %A Shneiderman, Ben %K Computer science %K data visualisation %K Educational institutions %K Guidelines %K hierarchical visualization %K HUMANS %K Information Visualization %K Laboratories %K multidimensional visualization %K Portable computers %K Testing %K usability %K User interfaces %K Visualization %X Summary form only given. The enthusiasm for information visualization has generated a wide variety of interesting tools for multi-dimensional, hierarchical, and other kinds of visualizations. However, some designs are readily accepted as understandable and useful, while others are perceived as confusing and useless. Controlled studies have begun to sort of some of the issues, but the insights of designers and usability tests are contributing interesting cognitive hypotheses for researchers and practical guidelines for developers. This paper offers examples of what works and what doesn't with a preliminary set of principles that might have wide applicability. %B Eighth International Conference on Information Visualisation, 2004. IV 2004. Proceedings %I IEEE %8 2004/07/14/16 %@ 0-7695-2177-0 %G eng %R 10.1109/IV.2004.1320117 %0 Conference Paper %B 13th International Conference on Computer Communications and Networks, 2004. ICCCN 2004. Proceedings %D 2004 %T High-performance MAC for high-capacity wireless LANs %A Yuan Yuan %A Daqing Gu %A Arbaugh, William A. %A Jinyun Zhang %K 35 Mbit/s %K access protocols %K Aggregates %K Bandwidth %K batch transmission %K Computer science %K Educational institutions %K high-capacity wireless LAN %K high-performance MAC %K Laboratories %K Local area networks %K Media Access Protocol %K opportunistic selection %K Physical layer %K probability %K Throughput %K Wireless LAN %X The next-generation wireless technologies, e.g., 802.11n and 802.15.3a, offer a physical-layer speed at least an-order-of-magnitude higher than the current standards. However, direct application of current MACs leads to high protocol overhead and significant throughput degradation. In this paper, we propose ADCA, a high-performance MAC that works with high-capacity physical layer. ADCA exploits two ideas of adaptive batch transmission and opportunistic selection of high-rate hosts to simultaneously reduce the overhead and improve the aggregate throughput. It opportunistically favors high-rate hosts by providing higher access probability and more access time, while ensuring each low-rate host certain minimum amount of channel access time. Simulations show that the ADCA design increases the throughput by 112% and reduces the average delay by 55% compared with the legacy DCF. It delivers more than 100 Mbps MAC-layer throughput as compared with 35 Mbps offered by the legacy MAC %B 13th International Conference on Computer Communications and Networks, 2004. ICCCN 2004. Proceedings %I IEEE %P 167 - 172 %8 2004/10/11/13 %@ 0-7803-8814-3 %G eng %R 10.1109/ICCCN.2004.1401615 %0 Conference Paper %B IEEE Symposium on Information Visualization, 2004. INFOVIS 2004 %D 2004 %T A Rank-by-Feature Framework for Unsupervised Multidimensional Data Exploration Using Low Dimensional Projections %A Seo,J. %A Shneiderman, Ben %K axis-parallel projections %K boxplot %K color-coded lower-triangular matrix %K computational complexity %K computational geometry %K Computer displays %K Computer science %K Computer vision %K Data analysis %K data mining %K data visualisation %K Data visualization %K Displays %K dynamic query %K Educational institutions %K exploratory data analysis %K feature detection %K feature detection/selection %K Feature extraction %K feature selection %K graph theory %K graphical displays %K histogram %K Information Visualization %K interactive systems %K Laboratories %K Multidimensional systems %K Principal component analysis %K rank-by-feature prism %K scatterplot %K statistical analysis %K statistical graphics %K statistical graphs %K unsupervised multidimensional data exploration %K very large databases %X Exploratory analysis of multidimensional data sets is challenging because of the difficulty in comprehending more than three dimensions. Two fundamental statistical principles for the exploratory analysis are (1) to examine each dimension first and then find relationships among dimensions, and (2) to try graphical displays first and then find numerical summaries (D.S. Moore, (1999). We implement these principles in a novel conceptual framework called the rank-by-feature framework. In the framework, users can choose a ranking criterion interesting to them and sort 1D or 2D axis-parallel projections according to the criterion. We introduce the rank-by-feature prism that is a color-coded lower-triangular matrix that guides users to desired features. Statistical graphs (histogram, boxplot, and scatterplot) and information visualization techniques (overview, coordination, and dynamic query) are combined to help users effectively traverse 1D and 2D axis-parallel projections, and finally to help them interactively find interesting features %B IEEE Symposium on Information Visualization, 2004. INFOVIS 2004 %I IEEE %P 65 - 72 %8 2004/// %@ 0-7803-8779-3 %G eng %R 10.1109/INFVIS.2004.3 %0 Conference Paper %B Proceedings of the 36th Annual Hawaii International Conference on System Sciences, 2003 %D 2003 %T The effect of bilingual term list size on dictionary-based cross-language information retrieval %A Demner-Fushman,D. %A Oard, Douglas %K bilingual term list %K Chinese language %K Computer science %K Control systems %K Cross-language information retrieval %K data mining %K Dictionaries %K dictionary-based information retrieval %K Educational institutions %K English language %K Frequency %K Information retrieval %K language translation %K named-entity translation %K natural languages %K Surface morphology %K Terminology %X Bilingual term lists are extensively used as a resource for dictionary-based cross-language information retrieval (CLIR), in which the goal is to find documents written in one natural language based on queries that are expressed in another. This paper identifies eight types of terms that affect retrieval effectiveness in CLIR applications through their coverage by general-purpose bilingual term lists, and reports results from an experimental evaluation of the coverage of 35 bilingual term lists in news retrieval application. Retrieval effectiveness was found to be strongly influenced by term list size for lists that contain between 3,000 and 30,000 unique terms per language. Supplemental techniques for named entity translation were found to be useful with even the largest lexicons. The contribution of named-entity translation was evaluated in a cross-language experiment involving English and Chinese. Smaller effects were observed from deficiencies in the coverage of domain-specific terminology when searching news stories. %B Proceedings of the 36th Annual Hawaii International Conference on System Sciences, 2003 %I IEEE %8 2003/01/06/9 %@ 0-7695-1874-5 %G eng %R 10.1109/HICSS.2003.1174250 %0 Conference Paper %B 2003 IEEE/RSJ International Conference on Intelligent Robots and Systems, 2003. (IROS 2003). Proceedings %D 2003 %T Efficient particle filter-based tracking of multiple interacting targets using an MRF-based motion model %A Zia Khan %A Balch, T. %A Dellaert, F. %K collision avoidance %K computational cost %K Computational efficiency %K Educational institutions %K exponential complexity %K Filtering %K filtering theory %K Insects %K joint particle tracker %K Markov processes %K Markov random field motion %K Markov random fields %K multiple interacting targets %K particle filter-based tracking %K Particle filters %K Particle tracking %K Radar tracking %K social insect tracking application %K target tracking %K Trajectory %X We describe a multiple hypothesis particle filter for tracking targets that are influenced by the proximity and/or behavior of other targets. Our contribution is to show how a Markov random field motion prior, built on the fly at each time step, can model these interactions to enable more accurate tracking. We present results for a social insect tracking application, where we model the domain knowledge that two targets cannot occupy the same space, and targets actively avoid collisions. We show that using this model improves track quality and efficiency. Unfortunately, the joint particle tracker we propose suffers from exponential complexity in the number of tracked targets. An approximation to the joint filter, however, consisting of multiple nearly independent particle filters can provide similar track quality at substantially lower computational cost. %B 2003 IEEE/RSJ International Conference on Intelligent Robots and Systems, 2003. (IROS 2003). Proceedings %V 1 %P 254 - 259 vol.1 %8 2003/10// %G eng %0 Conference Paper %B 3rd IEEE/ACM International Symposium on Cluster Computing and the Grid, 2003. Proceedings. CCGrid 2003 %D 2003 %T Improving access to multi-dimensional self-describing scientific datasets %A Nam,B. %A Sussman, Alan %K Application software %K application-specific semantic metadata %K Bandwidth %K Computer science %K database indexing %K disk I/O bandwidth %K distributed databases %K Educational institutions %K Indexing %K indexing structures %K Libraries %K meta data %K Middleware %K multidimensional arrays %K multidimensional datasets %K Multidimensional systems %K NASA %K NASA remote sensing data %K Navigation %K query formulation %K self-describing scientific data file formats %K structural metadata %K very large databases %X Applications that query into very large multidimensional datasets are becoming more common. Many self-describing scientific data file formats have also emerged, which have structural metadata to help navigate the multi-dimensional arrays that are stored in the files. The files may also contain application-specific semantic metadata. In this paper, we discuss efficient methods for performing searches for subsets of multi-dimensional data objects, using semantic information to build multidimensional indexes, and group data items into properly sized chunks to maximize disk I/O bandwidth. This work is the first step in the design and implementation of a generic indexing library that will work with various high-dimension scientific data file formats containing semantic information about the stored data. To validate the approach, we have implemented indexing structures for NASA remote sensing data stored in the HDF format with a specific schema (HDF-EOS), and show the performance improvements that are gained from indexing the datasets, compared to using the existing HDF library for accessing the data. %B 3rd IEEE/ACM International Symposium on Cluster Computing and the Grid, 2003. Proceedings. CCGrid 2003 %I IEEE %P 172 - 179 %8 2003/05/12/15 %@ 0-7695-1919-9 %G eng %R 10.1109/CCGRID.2003.1199366 %0 Conference Paper %B 14th IEEE Proceedings on Personal, Indoor and Mobile Radio Communications, 2003. PIMRC 2003 %D 2003 %T A secure service discovery protocol for MANET %A Yuan Yuan %A Arbaugh, William A. %K ad hoc networks %K centralized administration %K Computer architecture %K Computer science %K dynamic service discovery infrastructure %K Educational institutions %K MANET %K Manuals %K mobile ad hoc network %K Mobile ad hoc networks %K Mobile computing %K mobile radio %K noninfrastructure network %K Pervasive computing %K Protocols %K routing protocols %K secure service discovery protocol %K Security %K service discovery techniques %K service discovery technologies %K telecommunication computing %K telecommunication services %K XML %X Service discovery technologies are exploited to enable services to advertise their existence in a dynamic way, and can be discovered, configured and used by other devices with minimum manual efforts. It plays an essential role in future network scenarios especially with development of mobile ad hoc network (MANET) and emergence of pervasive computing. Because MANET allows these devices to communicate dynamically without fixed infrastructure and centralized administration, it gives rise to the challenges of the service discovery techniques. In this paper, we present a dynamic service discovery infrastructure that uses XML to describe services and match using the semantic content of service descriptions for MANET. We believe that the architecture we have designed is a necessary component of service discovery in non-infrastructure network by further exploring the secure and performance issues of this infrastructure. %B 14th IEEE Proceedings on Personal, Indoor and Mobile Radio Communications, 2003. PIMRC 2003 %I IEEE %V 1 %P 502- 506 Vol.1 - 502- 506 Vol.1 %8 2003/09/07/10 %@ 0-7803-7822-9 %G eng %R 10.1109/PIMRC.2003.1264322 %0 Conference Paper %B 2003 IEEE Conference on Open Architectures and Network Programming %D 2003 %T User-specified adaptive scheduling in a streaming media network %A Hicks, Michael W. %A Nagarajan,A. %A van Renesse,R. %K Adaptive scheduling %K CAMERAS %K Computer networks %K Computer science %K distributed stream processing system %K Educational institutions %K global resource scheduling %K Intelligent networks %K MediaNet %K Mobile computing %K network utilization %K Process design %K Processor scheduling %K quality of service %K Streaming media %K streaming media network %K user performance %K user-specified adaptive scheduling %X In disaster and combat situations, mobile cameras and other sensors transmit real-time data, used by many operators or analysis tools. Unfortunately, in the face of limited, unreliable resources, and varying demands, not all users may be able to get the fidelity they require. This paper describes MediaNet, a distributed stream processing system designed with the above scenarios in mind. Unlike past approaches, MediaNet's users can intuitively specify how the system should adapt based on their individual needs. MediaNet uses both local and online global resource scheduling to improve user performance and network utilization, and adapts without requiring underlying support for resource reservations. Performance experiments show that our scheduling algorithm is reasonably fast, and that user performance and network utilization are both significantly improved. %B 2003 IEEE Conference on Open Architectures and Network Programming %I IEEE %P 87 - 96 %8 2003/04/04/5 %@ 0-7803-7764-8 %G eng %R 10.1109/OPNARC.2003.1196376 %0 Conference Paper %B IEEE INFOCOM 2002. Twenty-First Annual Joint Conference of the IEEE Computer and Communications Societies. Proceedings %D 2002 %T Clustering and server selection using passive monitoring %A Andrews,M. %A Shepherd,B. %A Srinivasan, Aravind %A Winkler,P. %A Zane,F. %K client assignment %K client-server systems %K clustering %K content servers %K Delay %K distributed system %K Educational institutions %K Internet %K IP addresses %K Monitoring %K network conditions %K Network servers %K Network topology %K optimal content server %K passive monitoring %K server selection %K Space technology %K TCPIP %K Transport protocols %K Web pages %K Web server %K Webmapper %X We consider the problem of client assignment in a distributed system of content servers. We present a system called Webmapper for clustering IP addresses and assigning each cluster to an optimal content server. The system is passive in that the only information it uses comes from monitoring the TCP connections between the clients and the servers. It is also flexible in that it makes no a priori assumptions about network topology and server placement and it can react quickly to changing network conditions. We present experimental results to evaluate the performance of Webmapper. %B IEEE INFOCOM 2002. Twenty-First Annual Joint Conference of the IEEE Computer and Communications Societies. Proceedings %I IEEE %V 3 %P 1717- 1725 vol.3 - 1717- 1725 vol.3 %8 2002/// %@ 0-7803-7476-2 %G eng %R 10.1109/INFCOM.2002.1019425 %0 Conference Paper %B The 43rd Annual IEEE Symposium on Foundations of Computer Science, 2002. Proceedings %D 2002 %T Dependent rounding in bipartite graphs %A Gandhi,R. %A Khuller, Samir %A Parthasarathy,S. %A Srinivasan, Aravind %K Application software %K Approximation algorithms %K bipartite graph %K bipartite graphs %K broadcast channels %K broadcast scheduling %K Broadcasting %K capacitated vertex cover %K Character generation %K computational complexity %K Computer science %K Delay %K edge-sets %K Educational institutions %K fair scheduling %K fractional vectors %K graph theory %K per-user fairness properties %K pipage rounding technique %K Processor scheduling %K Random variables %K random-graph models %K randomized rounding approach %K rounding method %K scheduling %K Scheduling algorithm %K telecommunication computing %K unrelated parallel machines %X We combine the pipage rounding technique of Ageev & Sviridenko with a recent rounding method developed by Srinivasan (2001), to develop a new randomized rounding approach for fractional vectors defined on the edge-sets of bipartite graphs. We show various ways of combining this technique with other ideas, leading to the following applications: richer random-graph models for graphs with a given degree-sequence; improved approximation algorithms for: (i) throughput-maximization in broadcast scheduling, (ii) delay-minimization in broadcast scheduling, and (iii) capacitated vertex cover; fair scheduling of jobs on unrelated parallel machines. A useful feature of our method is that it lets us prove certain (probabilistic) per-user fairness properties. %B The 43rd Annual IEEE Symposium on Foundations of Computer Science, 2002. Proceedings %I IEEE %P 323 - 332 %8 2002/// %@ 0-7695-1822-2 %G eng %R 10.1109/SFCS.2002.1181955 %0 Conference Paper %B Third Workshop on Omnidirectional Vision, 2002. Proceedings %D 2002 %T Eyes from eyes: new cameras for structure from motion %A Neumann, J. %A Fermüller, Cornelia %A Aloimonos, J. %K Algorithm design and analysis %K Camera design %K CAMERAS %K Design automation %K differential stereo %K Educational institutions %K ego-motion estimation %K Eyes %K Geometrical optics %K IMAGE PROCESSING %K Layout %K Motion estimation %K observed scene %K Optical films %K polydioptric camera %K RETINA %X We investigate the relationship between camera design and the problem of recovering the motion and structure of a scene from video data. The visual information that could possibly be obtained is described by the plenoptic function. A camera can be viewed as a device that captures a subset of this function, that is, it measures some of the light rays in some part of the space. The information contained in the subset determines how difficult it is to solve subsequent interpretation processes. By examining the differential structure of the time varying plenoptic function we relate different known and new camera models to the spatiotemporal structure of the observed scene. This allows us to define a hierarchy of camera designs, where the order is determined by the stability and complexity of the computations necessary to estimate structure and motion. At the low end of this hierarchy is the standard planar pinhole camera for which the structure from motion problem is non-linear and ill-posed. At the high end is a new camera, which we call the full field of view polydioptric camera, for which the problem is linear and stable. In between are multiple-view cameras with large fields of view which we have built, as well as catadioptric panoramic sensors and other omni-directional cameras. We develop design suggestions for the polydioptric camera, and based upon this new design we propose a linear algorithm for ego-motion estimation, which in essence combines differential motion estimation with differential stereo. %B Third Workshop on Omnidirectional Vision, 2002. Proceedings %I IEEE %P 19 - 26 %8 2002/// %@ 0-7695-1629-7 %G eng %R 10.1109/OMNVIS.2002.1044486 %0 Conference Paper %B 2002 International Symposium on Technology and Society, 2002. (ISTAS'02) %D 2002 %T Improving Web-based civic information access: a case study of the 50 US states %A Ceaparu,I. %A Shneiderman, Ben %K Computer aided software engineering %K Computer science %K contact information %K Educational institutions %K government data processing %K Guidelines %K home page design features %K information resources %K Laboratories %K Modems %K Navigation %K online help %K privacy %K privacy policies %K search boxes %K Tagging %K Uniform resource locators %K US states %K USA %K User interfaces %K Web sites %K Web-based civic information access %X An analysis of the home pages of all fifty US states reveals great variety in key design features that influence efficacy. Some states had excessively large byte counts that would slow users connected by commonly-used 56 K modems. Many web sites had low numbers of or poorly organized links that would make it hard for citizens to find what they were interested in. Features such as search boxes, privacy policies, online help, or contact information need to be added by several states. Our analysis concludes with ten recommendations and finds many further opportunities for individual states to improve their Websites. However still greater benefits will come through collaboration among the states that would lead to consistency, appropriate tagging, and common tools. %B 2002 International Symposium on Technology and Society, 2002. (ISTAS'02) %I IEEE %P 275 - 282 %8 2002/// %@ 0-7803-7284-0 %G eng %R 10.1109/ISTAS.2002.1013826 %0 Conference Paper %B 2002 IEEE Symposium on Security and Privacy, 2002. Proceedings %D 2002 %T P5 : a protocol for scalable anonymous communication %A Sherwood,R. %A Bhattacharjee, Bobby %A Srinivasan, Aravind %K Broadcasting %K communication efficiency %K Computer science %K cryptography %K data privacy %K Educational institutions %K Internet %K large anonymous groups %K P5 protocol %K packet-level simulations %K Particle measurements %K Peer to peer computing %K peer-to-peer personal privacy protocol %K privacy %K Protocols %K receiver anonymity %K scalable anonymous communication %K security of data %K sender anonymity %K sender-receiver anonymity %K Size measurement %K telecommunication security %X We present a protocol for anonymous communication over the Internet. Our protocol, called P5 (peer-to-peer personal privacy protocol) provides sender-, receiver-, and sender-receiver anonymity. P5 is designed to be implemented over current Internet protocols, and does not require any special infrastructure support. A novel feature of P5 is that it allows individual participants to trade-off degree of anonymity for communication efficiency, and hence can be used to scalably implement large anonymous groups. We present a description of P5, an analysis of its anonymity and communication efficiency, and evaluate its performance using detailed packet-level simulations. %B 2002 IEEE Symposium on Security and Privacy, 2002. Proceedings %I IEEE %P 58 - 70 %8 2002/// %@ 0-7695-1543-6 %G eng %R 10.1109/SECPRI.2002.1004362 %0 Conference Paper %B Parallel and Distributed Processing Symposium., Proceedings International, IPDPS 2002, Abstracts and CD-ROM %D 2002 %T Scheduling multiple data visualization query workloads on a shared memory machine %A Andrade,H. %A Kurc, T. %A Sussman, Alan %A Saltz, J. %K Atomic force microscopy %K Biomedical informatics %K Computer science %K Data analysis %K data visualisation %K Data visualization %K datasets %K deductive databases %K digitized microscopy image browsing %K directed graph %K directed graphs %K dynamic query scheduling model %K Educational institutions %K high workloads %K image database %K limited resources %K multiple data visualization query workloads %K multiple query optimization %K performance %K priority queue %K Processor scheduling %K Query processing %K query ranking %K Relational databases %K scheduling %K shared memory machine %K shared memory systems %K Virtual Microscope %K visual databases %X Query scheduling plays an important role when systems are faced with limited resources and high workloads. It becomes even more relevant for servers applying multiple query optimization techniques to batches of queries, in which portions of datasets as well as intermediate results are maintained in memory to speed up query evaluation. We present a dynamic query scheduling model based on a priority queue implementation using a directed graph and a strategy for ranking queries. We examine the relative performance of several ranking strategies on a shared-memory machine using two different versions of an application, called the Virtual Microscope, for browsing digitized microscopy images %B Parallel and Distributed Processing Symposium., Proceedings International, IPDPS 2002, Abstracts and CD-ROM %I IEEE %P 11 - 18 %8 2002/// %@ 0-7695-1573-8 %G eng %R 10.1109/IPDPS.2002.1015482 %0 Conference Paper %B Fifth International Conference on Information Visualisation, 2001. Proceedings %D 2001 %T Dynamic queries and brushing on choropleth maps %A Dang,G. %A North,C. %A Shneiderman, Ben %K brushing %K business %K cartography %K choropleth maps %K color coding %K colour graphics %K complex data sets %K Computational Intelligence Society %K Computer science %K data visualisation %K Data visualization %K demographic data %K Demography %K Dynamaps %K dynamic queries %K economic data %K Educational institutions %K geographic information system %K geographic information systems %K Joining processes %K map representations %K map-based information visualization %K Query processing %K Scattering %K scatterplot view %K tabular representations %K user interface %K User interfaces %K World Wide Web %X Users who must combine demographic, economic or other data in a geographic context are often hampered by the integration of tabular and map representations. Static, paper-based solutions limit the amount of data that can be placed on a single map or table. By providing an effective user interface, we believe that researchers, journalists, teachers, and students can explore complex data sets more rapidly and effectively. This paper presents Dynamaps, a generalized map-based information visualization tool for dynamic queries and brushing on choropleth maps. Users can use color coding to show a variable on each geographic region, and then filter out areas that do not meet the desired criteria. In addition, a scatterplot view and a details-on-demand window support overviews and specific fact-finding %B Fifth International Conference on Information Visualisation, 2001. Proceedings %I IEEE %P 757 - 764 %8 2001/// %@ 0-7695-1195-3 %G eng %R 10.1109/IV.2001.942141 %0 Conference Paper %B Applications of Signal Processing to Audio and Acoustics, 2001 IEEE Workshop on the %D 2001 %T Efficient evaluation of reverberant sound fields %A Duraiswami, Ramani %A Gumerov, Nail A. %A Zotkin,Dmitry N %A Davis, Larry S. %K AB algorithm %K acoustic signal processing %K architectural acoustics %K audio signal processing %K Computational modeling %K Computer interfaces %K Computer simulation %K Educational institutions %K image method %K image sources %K Impedance %K Laboratories %K microphone arrays %K multipole expansions %K Nails %K performance evaluation %K reverberant sound fields %K reverberation %K room reverberation %K simulation %K Simulations %K speedup %K virtual audio %X An image method due to Allen and Berkley (1979) is often used to simulate the effect of reverberation in rooms. This method is relatively expensive computationally. We present a fast method for conducting such simulations using multipole expansions. For M real and image sources and N evaluation points, while the image method requires O(MN) operations, our method achieves the calculations in O(M + N) operations, resulting in a substantial speedup. Applications of our technique are also expected in simulation of virtual audio %B Applications of Signal Processing to Audio and Acoustics, 2001 IEEE Workshop on the %I IEEE %P 203 - 206 %8 2001/// %@ 0-7803-7126-7 %G eng %R 10.1109/ASPAA.2001.969578 %0 Conference Paper %B Thirteenth International Conference on Scientific and Statistical Database Management, 2001. SSDBM 2001. Proceedings %D 2001 %T Integrating distributed scientific data sources with MOCHA and XRoaster %A Rodriguez-Martinez,M. %A Roussopoulos, Nick %A McGann,J. M %A Kelley,S. %A Mokwa,J. %A White,B. %A Jala,J. %K client-server systems %K data sets %K data sites %K Databases %K Distributed computing %K distributed databases %K distributed scientific data source integration %K Educational institutions %K graphical tool %K hypermedia markup languages %K IP networks %K java %K Large-scale systems %K Maintenance engineering %K meta data %K metadata %K Middleware %K middleware system %K MOCHA %K Query processing %K remote sites %K scientific information systems %K user-defined types %K visual programming %K XML %K XML metadata elements %K XML-based framework %K XRoaster %X MOCHA is a novel middleware system for integrating distributed data sources that we have developed at the University of Maryland. MOCHA is based on the idea that the code that implements user-defined types and functions should be automatically deployed to remote sites by the middleware system itself. To this end, we have developed an XML-based framework to specify metadata about data sites, data sets, and user-defined types and functions. XRoaster is a graphical tool that we have developed to help the user create all the XML metadata elements to be used in MOCHA %B Thirteenth International Conference on Scientific and Statistical Database Management, 2001. SSDBM 2001. Proceedings %I IEEE %P 263 - 266 %8 2001/// %@ 0-7695-1218-6 %G eng %R 10.1109/SSDM.2001.938560 %0 Conference Paper %B 2001 IEEE International Conference on Acoustics, Speech, and Signal Processing, 2001. Proceedings. (ICASSP '01) %D 2001 %T Modeling the effect of a nearby boundary on the HRTF %A Gumerov, Nail A. %A Duraiswami, Ramani %K Acoustic scattering %K acoustic signal processing %K acoustic wave reflection %K acoustic wave scattering %K architectural acoustics %K audio signal processing %K Biological system modeling %K boundary effect modeling %K Computer interfaces %K Ear %K Educational institutions %K Frequency %K Head related transfer function %K HRTF %K HUMANS %K infinite plane %K Laboratories %K Nails %K Raman scattering %K rigid surface %K room environment %K sound pressure level %K sound scattering %K spatial audio %K sphere %K spherical model %K Transfer functions %K wall influence %X Understanding and simplified modeling of the head related transfer function (HRTF) holds the key to many applications in spatial audio. We develop an analytical solution to the problem of scattering of sound from a sphere in the vicinity of an infinite plane. Using this solution we study the influence of a nearby scattering rigid surface, on a spherical model for the HRTF %B 2001 IEEE International Conference on Acoustics, Speech, and Signal Processing, 2001. Proceedings. (ICASSP '01) %I IEEE %V 5 %P 3337-3340 vol.5 - 3337-3340 vol.5 %8 2001/// %@ 0-7803-7041-4 %G eng %R 10.1109/ICASSP.2001.940373 %0 Conference Paper %B IEEE Workshop on Detection and Recognition of Events in Video, 2001. Proceedings %D 2001 %T Multimodal 3-D tracking and event detection via the particle filter %A Zotkin,Dmitry N %A Duraiswami, Ramani %A Davis, Larry S. %K algorithms %K APPROACH %K audio data collection %K audio signal processing %K Bayesian inference %K Bayesian methods %K belief networks %K CAMERAS %K capture %K conversation %K echo %K Educational institutions %K Event detection %K event occurrence %K filtering theory %K flying echo locating bat behaviour %K Image motion analysis %K inference mechanisms %K Laboratories %K microphone arrays %K moving object tracking %K moving participants %K moving prey %K multimodal 3D tracking %K multiple cameras %K Object detection %K particle filter %K Particle filters %K Particle tracking %K Robustness %K search %K smart video conferencing setup %K target tracking %K Teleconferencing %K tracking filters %K turn-taking detection %K video data collection %K video signal processing %X Determining the occurrence of an event is fundamental to developing systems that can observe and react to them. Often, this determination is based on collecting video and/or audio data and determining the state or location of a tracked object. We use Bayesian inference and the particle filter for tracking moving objects, using both video data obtained from multiple cameras and audio data obtained using arrays of microphones. The algorithms developed are applied to determining events arising in two fields of application. In the first, the behavior of a flying echo locating bat as it approaches a moving prey is studied, and the events of search, approach and capture are detected. In a second application we describe detection of turn-taking in a conversation between possibly moving participants recorded using a smart video conferencing setup %B IEEE Workshop on Detection and Recognition of Events in Video, 2001. Proceedings %I IEEE %P 20 - 27 %8 2001/// %@ 0-7695-1293-3 %G eng %R 10.1109/EVENT.2001.938862 %0 Conference Paper %B Proceedings of the IEEE 2nd International Symposium on Bioinformatics and Bioengineering Conference, 2001 %D 2001 %T Optimized seamless integration of biomolecular data %A Eckman,B. A %A Lacroix,Z. %A Raschid, Louiqa %K analysis %K Bioinformatics %K biology computing %K cost based knowledge %K Costs %K Data analysis %K data mining %K data visualisation %K Data visualization %K Data warehouses %K decision support %K digital library %K Educational institutions %K information resources %K Internet %K low cost query evaluation plans %K Mediation %K meta data %K metadata %K molecular biophysics %K multiple local heterogeneous data sources %K multiple remote heterogeneous data sources %K optimized seamless biomolecular data integration %K scientific discovery %K scientific information systems %K semantic knowledge %K software libraries %K visual databases %K Visualization %X Today, scientific data is inevitably digitized, stored in a variety of heterogeneous formats, and is accessible over the Internet. Scientists need to access an integrated view of multiple remote or local heterogeneous data sources. They then integrate the results of complex queries and apply further analysis and visualization to support the task of scientific discovery. Building a digital library for scientific discovery requires accessing and manipulating data extracted from flat files or databases, documents retrieved from the Web, as well as data that is locally materialized in warehouses or is generated by software. We consider several tasks to provide optimized and seamless integration of biomolecular data. Challenges to be addressed include capturing and representing source capabilities; developing a methodology to acquire and represent metadata about source contents and access costs; and decision support to select sources and capabilities using cost based and semantic knowledge, and generating low cost query evaluation plans %B Proceedings of the IEEE 2nd International Symposium on Bioinformatics and Bioengineering Conference, 2001 %I IEEE %P 23 - 32 %8 2001/11/04/6 %@ 0-7695-1423-5 %G eng %R 10.1109/BIBE.2001.974408 %0 Conference Paper %B 2001 IEEE Symposium on Security and Privacy, 2001. S&P 2001. Proceedings %D 2001 %T A trend analysis of exploitations %A Browne,H. K %A Arbaugh, William A. %A McHugh,J. %A Fithen,W. L %K Computer science %K computer security exploits %K Data analysis %K data mining %K Educational institutions %K exploitations %K Performance analysis %K Predictive models %K Regression analysis %K Risk management %K security of data %K software engineering %K system intrusions %K System software %K trend analysis %K vulnerabilities %K vulnerability exploitation %X We have conducted an empirical study of a number of computer security exploits and determined that the rates at which incidents involving the exploit are reported to CERT can be modeled using a common mathematical framework. Data associated with three significant exploits involving vulnerabilities in phf, imap, and bind can all be modeled using the formula C=I+S×√M where C is the cumulative count of reported incidents, M is the time since the start of the exploit cycle, and I and S are the regression coefficients determined by analysis of the incident report data. Further analysis of two additional exploits involving vulnerabilities in mountd and statd confirm the model. We believe that the models will aid in predicting the severity of subsequent vulnerability exploitations, based on the rate of early incident reports %B 2001 IEEE Symposium on Security and Privacy, 2001. S&P 2001. Proceedings %I IEEE %P 214 - 229 %8 2001/// %@ 0-7695-1046-9 %G eng %R 10.1109/SECPRI.2001.924300 %0 Conference Paper %B IEEE International Conference on Information Visualization, 2000. Proceedings %D 2000 %T Direct annotation: a drag-and-drop strategy for labeling photos %A Shneiderman, Ben %A Kang,H. %K Biomedical imaging %K Cities and towns %K Computer errors %K Computer science %K database indexing %K database schema %K Databases %K digital libraries %K direct annotation %K direct manipulation %K drag-and-drop strategy %K Educational institutions %K graphical user interface %K Graphical user interfaces %K History %K hobby computing %K image searching %K label placement %K Labeling %K Laboratories %K Libraries %K personal information systems %K personal names database %K PhotoFinder prototype %K photograph labelling %K photographic libraries %K Photography %K scrolling list %K user interface design %K visual databases %X Annotating photographs is such a time-consuming, tedious and error-prone data entry task that it discourages most owners of personal photo libraries. By allowing the user to drag labels, such as personal names, from a scrolling list and drop them onto a photo, we believe we can make the task faster, easier and more appealing. Since the names are entered in a database, searching for all photos of a friend or family member is dramatically simplified. We describe the user interface design and the database schema to support direct annotation, as implemented in our PhotoFinder prototype %B IEEE International Conference on Information Visualization, 2000. Proceedings %I IEEE %P 88 - 95 %8 2000/// %@ 0-7695-0743-3 %G eng %R 10.1109/IV.2000.859742 %0 Conference Paper %B 11th International Workshop on Database and Expert Systems Applications, 2000. Proceedings %D 2000 %T Domain name based visualization of Web histories in a zoomable user interface %A Gandhi,R. %A Kumar,G. %A Bederson, Benjamin B. %A Shneiderman, Ben %K Computer science %K data visualisation %K domain name %K domain name based visualization %K Domain Tree Browser %K Educational institutions %K History %K hypermedia %K hypertext links %K hypertext systems %K information resources %K Navigation %K online front-ends %K thumbnails %K Tree graphs %K tree structured visual navigation history %K Uniform resource locators %K URLs %K User interfaces %K Visualization %K Web browser companion %K Web histories %K Web pages %K World Wide Web %K zoomable user interface %K zoomable window %X Users of hypertext systems like the World Wide Web (WWW) often find themselves following hypertext links deeper and deeper, only to find themselves “lost” and unable to find their way back to the previously visited pages. We have implemented a Web browser companion called Domain Tree Browser (DTB) that builds a tree structured visual navigation history while browsing the Web. The Domain Tree Browser organizes the URLs visited based on the domain name of each URL and shows thumbnails of each page in a zoomable window %B 11th International Workshop on Database and Expert Systems Applications, 2000. Proceedings %I IEEE %P 591 - 598 %8 2000/// %@ 0-7695-0680-1 %G eng %R 10.1109/DEXA.2000.875085 %0 Conference Paper %B Parallel and Distributed Processing Symposium, 2000. IPDPS 2000. Proceedings. 14th International %D 2000 %T Optimizing retrieval and processing of multi-dimensional scientific datasets %A Chang,Chialin %A Kurc, T. %A Sussman, Alan %A Saltz, J. %K active data repository %K Area measurement %K Computer science %K Data analysis %K distributed memory parallel machines %K Educational institutions %K Information retrieval %K Information Storage and Retrieval %K infrastructure %K Microscopy %K Microwave integrated circuits %K multi-dimensional scientific datasets retrieval %K PARALLEL PROCESSING %K Pathology %K range queries %K regular d-dimensional array %K Satellites %K Tomography %X We have developed the Active Data Repository (ADR), an infrastructure that integrates storage, retrieval, and processing of large multi-dimensional scientific datasets on distributed memory parallel machines with multiple disks attached to each node. In earlier work, we proposed three strategies for processing range queries within the ADR framework. Our experimental results show that the relative performance of the strategies changes under varying application characteristics and machine configurations. In this work we investigate approaches to guide and automate the selection of the best strategy for a given application and machine configuration. We describe analytical models to predict the relative performance of the strategies where input data elements are uniformly distributed in the attribute space of the output dataset, restricting the output dataset to be a regular d-dimensional array %B Parallel and Distributed Processing Symposium, 2000. IPDPS 2000. Proceedings. 14th International %I IEEE %P 405 - 410 %8 2000/// %@ 0-7695-0574-0 %G eng %R 10.1109/IPDPS.2000.846013 %0 Conference Paper %B Proceedings of the 33rd Annual Hawaii International Conference on System Sciences, 2000 %D 2000 %T Supporting creativity with powerful composition tools for artifacts and performances %A Shneiderman, Ben %K artifacts %K Artificial intelligence %K composition tools %K Computer science %K Context modeling %K creativity %K creativity support %K Educational institutions %K Information retrieval %K Laboratories %K Manufacturing %K music composition %K performances %K Software design %K software libraries %K software tools %K US Department of Transportation %X Modern software such as word processors, slide preparation/presentation tools, or music composition packages are designed to produce artifacts or performances. Now, some designers are expanding their goals to include creativity support into their software. This essay builds on the genex framework for creativity, which has four phases and eight activities. It focuses on the composition activity by considering tools to support initiation, revision, and evaluation. Some existing tools provide partial support that suggests ways in which to develop more ambitious low, middle, and high level tools. The goal is to enable more people to be more creative more of the time. %B Proceedings of the 33rd Annual Hawaii International Conference on System Sciences, 2000 %I IEEE %8 2000/01/04/7 %@ 0-7695-0493-0 %G eng %R 10.1109/HICSS.2000.926896 %0 Conference Paper %B 2000 IEEE International Conference on Multimedia and Expo, 2000. ICME 2000 %D 2000 %T Visualization methods for personal photo collections: browsing and searching in the PhotoFinder %A Kang,Hyunmo %A Shneiderman, Ben %K Browsing %K Computer science %K digital photo library %K Displays %K drag-and-drop interface %K dynamic query %K Educational institutions %K Filters %K Histograms %K Image retrieval %K personal computing %K personal photo collections %K photo collection management %K PhotoFinder %K Prototypes %K query preview %K scatter plot thumbnail display %K Scattering %K searching %K software libraries %K software tools %K User interfaces %K visual Boolean query interfaces %K visual databases %K Visualization %K visualization methods %X Software tools for personal photo collection management are proliferating, but they usually have limited searching and browsing functions. We implemented the PhotoFinder prototype to enable non-technical users of personal photo collections to search and browse easily. PhotoFinder provides a set of visual Boolean query interfaces, coupled with dynamic query and query preview features. It gives users powerful search capabilities. Using a scatter plot thumbnail display and drag-and-drop interface, PhotoFinder is designed to be easy to use for searching and browsing photos %B 2000 IEEE International Conference on Multimedia and Expo, 2000. ICME 2000 %I IEEE %V 3 %P 1539-1542 vol.3 - 1539-1542 vol.3 %8 2000/// %@ 0-7803-6536-4 %G eng %R 10.1109/ICME.2000.871061 %0 Conference Paper %B The Proceedings of the Seventh IEEE International Conference on Computer Vision, 1999 %D 1999 %T Estimation of composite object and camera image motion %A Yacoob,Yaser %A Davis, Larry S. %K articulated bodies %K camera image motion %K camera image motions %K CAMERAS %K composite independent object %K composite object estimation %K Computer vision %K Educational institutions %K Image sequences %K instantaneous flow measurements %K Laboratories %K Layout %K Motion analysis %K Motion estimation %K motion trajectories %K orthogonal flow bases %K Principal component analysis %K spatio-temporal flow models %K tracking %K Vehicles %X An approach for estimating composite independent object and camera image motions is proposed. The approach employs spatio-temporal flow models learned through observing typical movements of the object, to decompose image motion into independent object and camera motions. The spatio-temporal flow models of the object motion are represented as a set of orthogonal flow bases that are learned using principal component analysis of instantaneous flow measurements from a stationary camera. These models are then employed in scenes with a moving camera to extract motion trajectories relative to those learned. The performance of the algorithm is demonstrated on several image sequences of rigid and articulated bodies in motion %B The Proceedings of the Seventh IEEE International Conference on Computer Vision, 1999 %I IEEE %V 1 %P 190-197 vol.1 - 190-197 vol.1 %8 1999/// %@ 0-7695-0164-8 %G eng %R 10.1109/ICCV.1999.791217 %0 Conference Paper %B 18th International Conference on Distributed Computing Systems, 1998. Proceedings %D 1998 %T LBF: a performance metric for program reorganization %A Eom, H. %A Hollingsworth, Jeffrey K %K case study %K Computational modeling %K computer network %K Computer science %K Debugging %K distributed processing %K distributed program %K Educational institutions %K Integrated circuit testing %K LBF metric %K load balancing factor %K Load management %K measurement %K NIST %K parallel program %K parallel programming %K performance metric %K program reorganization %K program tuning %K Programming profession %K resource allocation %K software metrics %K software performance evaluation %K US Department of Energy %X We introduce a new performance metric, called Load Balancing Factor (LBF), to assist programmers with evaluating different tuning alternatives. The LBF metric differs from traditional performance metrics since it is intended to measure the performance implications of a specific tuning alternative rather than quantifying where time is spent in the current version of the program. A second unique aspect of the metric is that it provides guidance about moving work within a distributed or parallel program rather than reducing it. A variation of the LBF metric can also be used to predict the performance impact of changing the underlying network. The LBF metric can be computed incrementally and online during the execution of the program to be tuned. We also present a case study that shows that our metric can predict the actual performance gains accurately for a test suite of six programs %B 18th International Conference on Distributed Computing Systems, 1998. Proceedings %I IEEE %P 222 - 229 %8 1998/05/26/29 %@ 0-8186-8292-2 %G eng %R 10.1109/ICDCS.1998.679505 %0 Conference Paper %B Fourteenth International Conference on Pattern Recognition, 1998. Proceedings %D 1998 %T Pictorial query trees for query specification in image databases %A Soffer,A. %A Samet, Hanan %A Zotkin,Dmitry N %K Automation %K complex queries %K Computer science %K content-based retrieval %K Database systems %K database-image objects %K Educational institutions %K Electrical capacitance tomography %K grammars %K Image databases %K Image matching %K parsing %K pictorial query trees %K Postal services %K query specification %K query-image objects %K spatial constraints %K syntax %K visual databases %X A technique that enables specifying complex queries in image databases using pictorial query trees is presented. The leaves of a pictorial query tree correspond to individual pictorial queries that specify which objects should appear in the target images as well as how many occurrences of each object are required. In addition, the minimum required certainty of matching between query-image objects and database-image objects, as well as spatial constraints that specify bounds on the distance between objects and the relative direction between them are also specified. Internal nodes in the query tree represent logical operations (AND, OR, XOR) and their negations on the set of pictorial queries (or subtrees) represented by its children. The syntax of query trees is described. Algorithms for processing individual pictorial queries and for parsing and computing the overall result of a pictorial query tree are outlined %B Fourteenth International Conference on Pattern Recognition, 1998. Proceedings %I IEEE %V 1 %P 919-921 vol.1 - 919-921 vol.1 %8 1998/08// %@ 0-8186-8512-3 %G eng %R 10.1109/ICPR.1998.711383 %0 Conference Paper %B 3rd IFCIS International Conference on Cooperative Information Systems, 1998. Proceedings %D 1998 %T Wrapper generation for Web accessible data sources %A Gruser,J. %A Raschid, Louiqa %A Vidal,M. E %A Bright,L. %K application program interfaces %K data mining %K Databases %K Educational institutions %K Electrical capacitance tomography %K HTML %K HTML documents %K Internet %K Query processing %K Read only memory %K Search engines %K Specification languages %K Uniform resource locators %K World Wide Web %K wrapper generation toolkit %K WWW %X There is an increase in the number of data sources that can be queried across the WWW. Such sources typically support HTML forms-based interfaces and search engines query collections of suitably indexed data. The data is displayed via a browser: One drawback to these sources is that there is no standard programming interface suitable for applications to submit queries. Second, the output (answer to a query) is not well structured. Structured objects have to be extracted from the HTML documents which contain irrelevant data and which may be volatile. Third, domain knowledge about the data source is also embedded in HTML documents and must be extracted. To solve these problems, we present technology to define and (automatically) generate wrappers for Web accessible sources. Our contributions are as follows: (1) Defining a wrapper interface to specify the capability of Web accessible data sources. (2) Developing a wrapper generation toolkit of graphical interfaces and specification languages to specify the capability of sources and the functionality of the wrapper (3) Developing the technology to automatically generate a wrapper appropriate to the Web accessible source, from the specifications. %B 3rd IFCIS International Conference on Cooperative Information Systems, 1998. Proceedings %I IEEE %P 14 - 23 %8 1998/08/22/22 %@ 0-8186-8380-5 %G eng %R 10.1109/COOPIS.1998.706180 %0 Conference Paper %B , 1997 International Conference on Parallel Architectures and Compilation Techniques., 1997. Proceedings %D 1997 %T MDL: a language and compiler for dynamic program instrumentation %A Hollingsworth, Jeffrey K %A Niam, O. %A Miller, B. P %A Zhichen Xu %A Goncalves,M. J.R %A Ling Zheng %K Alpha architecture %K application program %K application program interfaces %K Application software %K compiler generators %K Computer science %K dynamic code generation %K Dynamic compiler %K dynamic program instrumentation %K Educational institutions %K files %K instrumentation code %K Instruments %K MDL %K measurement %K message channels %K Message passing %K Metric Description Language %K modules %K nodes %K Operating systems %K optimising compilers %K PA-RISC %K Paradyn Parallel Performance Tools %K Parallel architectures %K parallel programming %K performance data %K platform independent descriptions %K Power 2 architecture %K Power generation %K procedures %K program debugging %K Program processors %K running programs %K Runtime %K software metrics %K SPARC %K Specification languages %K x86 architecture %X We use a form of dynamic code generation, called dynamic instrumentation, to collect data about the execution of an application program. Dynamic instrumentation allows us to instrument running programs to collect performance and other types of information. The instrumentation code is generated incrementally and can be inserted and removed at any time. Our instrumentation currently runs on the SPARC, PA-RISC, Power 2, Alpha, and x86 architectures. Specification of what data to collect are written in a specialized language called the Metric Description Language, that is part of the Paradyn Parallel Performance Tools. This language allows platform independent descriptions of how to collect performance data. It also provides a concise way to specify, how to constrain performance data to particular resources such as modules, procedures, nodes, files, or message channels (or combinations of these resources). We also describe the details of how we weave instrumentation into a running program %B , 1997 International Conference on Parallel Architectures and Compilation Techniques., 1997. Proceedings %I IEEE %P 201 - 212 %8 1997/11/10/14 %@ 0-8186-8090-3 %G eng %R 10.1109/PACT.1997.644016 %0 Conference Paper %B Proceedings of the Third Forum on Research and Technology Advances in Digital Libraries, 1996. ADL '96 %D 1996 %T Query previews in networked information systems %A Donn,K. %A Plaisant, Catherine %A Shneiderman, Ben %K Computer networks %K data complexity %K data mining %K data patterns %K data volume %K dynamic query user interfaces %K Educational institutions %K EOS-DIS %K exploratory method %K Information retrieval %K Information services %K Information systems %K Intelligent networks %K interactive systems %K Laboratories %K Manipulator dynamics %K matching data sets %K NASA Earth Observing System-Data Information System %K Network performance %K networked environment %K networked information systems %K query formulation %K query preview %K query refinement %K querying process %K rough attribute values %K User interfaces %K visual databases %K zero hit queries %X In a networked information system (such as the NASA Earth Observing System-Data Information System (EOS-DIS)), there are three major obstacles facing users in a querying process: network performance, data volume and data complexity. In order to overcome these obstacles, we propose a two phase approach to query formulation. The two phases are the Query Preview and the Query Refinement. In the Query Preview phase, users formulate an initial query by selecting rough attribute values. The estimated number of matching data sets is shown, graphically on preview bars which allows users to rapidly focus on a manageable number of relevant data sets. Query previews also prevent wasted steps by eliminating zero hit queries. When the estimated number of data sets is long enough, the initial query is submitted to the network which returns the metadata of the data sets for further refinement in the Query Refinement phase. The two phase approach to query formulation overcomes slow network performance, and reduces the data volume and data complexity, problems. This approach is especially appropriate for users who do not have extensive knowledge about the data and who prefer an exploratory method to discover data patterns and exceptions. Using this approach, we have developed dynamic query user interfaces to allow users to formulate their queries across a networked environment %B Proceedings of the Third Forum on Research and Technology Advances in Digital Libraries, 1996. ADL '96 %I IEEE %P 120 - 129 %8 1996/05/13/15 %@ 0-8186-7403-2 %G eng %R 10.1109/ADL.1996.502522 %0 Conference Paper %B Frontiers of Massively Parallel Computation, 1995. Proceedings. Frontiers '95., Fifth Symposium on the %D 1995 %T Code generation for multiple mappings %A Kelly,W. %A Pugh, William %A Rosser,E. %K code generation %K Computer science %K Concurrent computing %K control overhead %K Educational institutions %K iteration reordering transformations %K Law %K Legal factors %K loop blocking %K multiple mappings %K optimisation %K optimising compilers %K Optimizing compilers %K PARALLEL PROCESSING %K Performance analysis %K program compilers %X There has been a great amount of recent work toward unifying iteration reordering transformations. Many of these approaches represent transformations as affine mappings from the original iteration space to a new iteration space. These approaches show a great deal of promise, but they all rely on the ability to generate code that iterates over the points in these new iteration spaces in the appropriate order. This problem has been fairly well-studied in the case where all statements use the same mapping. We have developed an algorithm for the less well-studied case where each statement uses a potentially different mapping. Unlike many other approaches, our algorithm can also generate code from mappings corresponding to loop blocking. We address the important trade-off between reducing control overhead and duplicating code %B Frontiers of Massively Parallel Computation, 1995. Proceedings. Frontiers '95., Fifth Symposium on the %I IEEE %P 332 - 341 %8 1995/02/06/9 %@ 0-8186-6965-9 %G eng %R 10.1109/FMPC.1995.380437 %0 Conference Paper %B , IEEE International Conference on Systems, Man and Cybernetics, 1995. Intelligent Systems for the 21st Century %D 1995 %T Experimental investigation of high performance cognitive and interactive text filtering %A Oard, Douglas %A DeClaris,N. %A Dorr, Bonnie J %A Faloutsos,C. %A Marchionini,G. %K Cause effect analysis %K Computer science %K Contracts %K Cornell SMART text retrieval system %K Educational institutions %K Gaussian User Model %K high performance cognitive interactive text filtering %K History %K Information filtering %K Information filters %K Information retrieval %K information retrieval system evaluation %K Libraries %K Matched filters %K online front-ends %K Query processing %K System testing %K text selection effectiveness %K user evaluations %K User interfaces %K user modelling %X Text filtering has become increasingly important as the volume of networked information has exploded in recent years. This paper reviews recent progress in that field and reports on the development of a testbed for experimental investigation of cognitive and interactive text selection based on a history of user evaluations. An interactive filtering system model is presented and a new cognitive filtering technique which the authors call the Gaussian User Model is described. Because development of analytic measures of text selection effectiveness has proven intractable, the authors have modified the Cornell SMART text retrieval system to create a flexible text filtering testbed for experimental determination of filtering effectiveness. The paper concludes with a description of the design of this testbed system %B , IEEE International Conference on Systems, Man and Cybernetics, 1995. Intelligent Systems for the 21st Century %I IEEE %V 5 %P 4398-4403 vol.5 - 4398-4403 vol.5 %8 1995/10/22/25 %@ 0-7803-2559-1 %G eng %R 10.1109/ICSMC.1995.538486 %0 Conference Paper %B , International Symposium on Computer Vision, 1995. Proceedings %D 1995 %T The information in the direction of image flow %A Brodsky, T. %A Fermüller, Cornelia %A Aloimonos, J. %K Automation %K CAMERAS %K Computer vision %K Educational institutions %K image flow %K Image motion analysis %K Image sequences %K imaging surface %K Laboratories %K Layout %K Motion analysis %K Motion estimation %K motion field %K motion vectors %K Optical imaging %K rigid motion %K rigid motions %K three-dimensional motion %X If instead of the full motion field, we consider only the direction of the motion field due to a rigid motion, what can we say about the information regarding the three-dimensional motion? In this paper it is shown that considering as the imaging surface the whole sphere, independently of the scene in view, two different rigid motions cannot give rise to the same directional motion field. If we restrict the image to half of a sphere (or an infinitely large image plane) two different rigid motions with instantaneous translational and rotational velocities (t1, ω1) and (t2, ω2) cannot give rise to the same directional motion field unless the plane through t1 and t2 is perpendicular to the plane through ω1 and ω2 (i.e., (t1×t2)·(ω1 ×ω2)=0). In addition, in order to give a practical significance to these uniqueness results for the case of a limited field of view we also characterize the locations on the image where the motion vectors due to the different motions must have different directions. If (ω1×ω2)·(t1 ×t2)=0 and certain additional constraints are met, then the two rigid motions could produce motion fields with the same direction. For this to happen the depth of each corresponding surface has to be within a certain range, defined by a second and a third order surface %B , International Symposium on Computer Vision, 1995. Proceedings %I IEEE %P 461 - 466 %8 1995/11/21/23 %@ 0-8186-7190-4 %G eng %R 10.1109/ISCV.1995.477071 %0 Conference Paper %B Proceedings of International Symposium on Computer Vision, 1995 %D 1995 %T Iso-distortion contours and egomotion estimation %A LoongFah Cheong %A Aloimonos, J. %K Automation %K Computer vision %K Degradation %K depth distortion %K Educational institutions %K egomotion estimation %K Equations %K erroneous motion estimates %K Error analysis %K HUMANS %K Image sequences %K iso-distortion contours %K Laboratories %K Layout %K Motion estimation %K Robustness %K visibility constraint %X This paper introduces the framework of iso-distortion contour to deal with the problem of depth distortion due to erroneous motion estimates, and various related aspects such as the effectiveness of the visibility constraint. The framework can also be used to inquire the uniqueness aspect of normal flow. Future work will examine the implications of the iso-distortion contours for the problem of multiple frame integration %B Proceedings of International Symposium on Computer Vision, 1995 %I IEEE %P 55 - 60 %8 1995/11/21/23 %@ 0-8186-7190-4 %G eng %R 10.1109/ISCV.1995.476977 %0 Conference Paper %B , 36th Annual Symposium on Foundations of Computer Science, 1995. Proceedings %D 1995 %T Splitters and near-optimal derandomization %A Naor,M. %A Schulman,L. J %A Srinivasan, Aravind %K Boosting %K Circuit testing %K computational complexity %K computational linguistics %K Computer science %K Contracts %K derandomization %K deterministic constructions %K Educational institutions %K Engineering profession %K exhaustive testing %K fairly general method %K fixed-subgraph finding algorithms %K hardness of approximation %K Information systems %K k-restrictions %K learning %K local-coloring protocol %K MATHEMATICS %K near-optimal constructions %K near-optimal derandomization %K Parallel algorithms %K probabilistic bound %K probability %K Protocols %K randomised algorithms %K Set cover %K splitters %X We present a fairly general method for finding deterministic constructions obeying what we call k-restrictions; this yields structures of size not much larger than the probabilistic bound. The structures constructed by our method include (n,k)-universal sets (a collection of binary vectors of length n such that for any subset of size k of the indices, all 2k configurations appear) and families of perfect hash functions. The near-optimal constructions of these objects imply the very efficient derandomization of algorithms in learning, of fixed-subgraph finding algorithms, and of near optimal ΣIIΣ threshold formulae. In addition, they derandomize the reduction showing the hardness of approximation of set cover. They also yield deterministic constructions for a local-coloring protocol, and for exhaustive testing of circuits %B , 36th Annual Symposium on Foundations of Computer Science, 1995. Proceedings %I IEEE %P 182 - 191 %8 1995/10/23/25 %@ 0-8186-7183-1 %G eng %R 10.1109/SFCS.1995.492475 %0 Conference Paper %B , 1994 IEEE International Conference on Systems, Man, and Cybernetics, 1994. 'Humans, Information and Technology' %D 1994 %T On automatic filtering of multilingual texts %A Oard, Douglas %A DeClaris,N. %A Dorr, Bonnie J %A Faloutsos,C. %K automated performance evaluation %K Business communication %K Computer science %K Discussion forums %K Displays %K Educational institutions %K Floods %K Government %K Information filtering %K Information filters %K Information retrieval %K multilingual information retrieval %K multilingual text filtering %K natural languages %K performance evaluation %X An emerging requirement to sift through the increasing flood of text information has led to the rapid development of information filtering technology in the past five years. This study introduces novel approaches for filtering texts regardless of their source language. We begin with a brief description of related developments in text filtering and multilingual information retrieval. We then present three alternative approaches to selecting texts from a multilingual information stream which represent a logical evolution from existing techniques in related disciplines. Finally, a practical automated performance evaluation technique is proposed %B , 1994 IEEE International Conference on Systems, Man, and Cybernetics, 1994. 'Humans, Information and Technology' %I IEEE %V 2 %P 1645-1650 vol.2 - 1645-1650 vol.2 %8 1994/10/02/5 %@ 0-7803-2129-4 %G eng %R 10.1109/ICSMC.1994.400083 %0 Journal Article %J IEEE Software %D 1994 %T Dynamic queries for visual information seeking %A Shneiderman, Ben %K Algorithm design and analysis %K animated results %K animation %K Application software %K Command languages %K complex queries %K database management systems %K Databases %K display algorithms %K Displays %K dynamic queries %K Educational institutions %K Games %K Graphical user interfaces %K human factors %K Query processing %K retrieval %K Runtime %K Technological innovation %K user-interface design %K visual databases %K visual information seeking %K visual interfaces %K widgets %X Considers how dynamic queries allow users to "fly through" databases by adjusting widgets and viewing the animated results. In studies, users reacted to this approach with an enthusiasm more commonly associated with video games. Adoption requires research into retrieval and display algorithms and user-interface design. The author discusses how experts may benefit from visual interfaces because they will be able to formulate more complex queries and interpret intricate results.<> %B IEEE Software %V 11 %P 70 - 77 %8 1994/11// %@ 0740-7459 %G eng %N 6 %R 10.1109/52.329404 %0 Journal Article %J IEEE Software %D 1993 %T Beyond intelligent machines: just do it %A Shneiderman, Ben %K Artificial intelligence %K Computer aided instruction %K Computer errors %K controllable interfaces %K Displays %K dynamic queries %K Educational institutions %K History %K HUMANS %K intelligent machines %K learning systems %K Machine intelligence %K predictable interfaces %K Speech recognition %K tree maps %K User interfaces %X The author argues that users want a sense of direct and immediate control over computers that differs from how they interact with people. He presents several examples of these predictable and controllable interfaces developed in the lab. The examples include tree maps and dynamic queries.<> %B IEEE Software %V 10 %P 100 - 103 %8 1993/01// %@ 0740-7459 %G eng %N 1 %R 10.1109/52.207235 %0 Conference Paper %B 1993 IEEE Computer Society Conference on Computer Vision and Pattern Recognition, 1993. Proceedings CVPR '93 %D 1993 %T Early vision processing using a multi-stage diffusion process %A Yacoob,Yaser %A Davis, Larry S. %K 3-D space %K Computational modeling %K Computer vision %K Diffusion processes %K discontinuity detection %K early vision processing %K Educational institutions %K Image edge detection %K Image segmentation %K Laboratories %K multistage diffusion process %K Noise shaping %K noise-free edges %K noisy edges %K Performance analysis %K roof edges %K segmentation %K SHAPE %K shape homogeneous regions %K step edges %K valley edges %X The use of a multistage diffusion process in the early processing of range data is examined. The input range data are interpreted as occupying a volume in 3-D space. Each diffusion stage simulates the process of diffusing part of the boundary of the volume into the volume. The outcome of the process can be used for both discontinuity detection and segmentation into shape homogeneous regions. The process is applied to synthetic noise-free and noisy step, roof, and valley edges as well as to real range images %B 1993 IEEE Computer Society Conference on Computer Vision and Pattern Recognition, 1993. Proceedings CVPR '93 %I IEEE %P 41 - 46 %8 1993/06// %@ 0-8186-3880-X %G eng %R 10.1109/CVPR.1993.341003 %0 Conference Paper %B , 1993 IEEE Computer Society Conference on Computer Vision and Pattern Recognition, 1993. Proceedings CVPR '93 %D 1993 %T Global 3D motion estimation %A Fermüller, Cornelia %K 3D motion parameters %K Automation %K axis of rotation %K Computer vision %K direction of translation %K Educational institutions %K Equations %K Fluid flow measurement %K global 3D motion estimation %K Laboratories %K Layout %K monocular observer %K Motion estimation %K Motion measurement %K normal flow measurements %K Robustness %K Rotation measurement %K search problems %K search technique %K State estimation %X It is shown how a monocular observer can estimate its 3D motion relative to the scene by using normal flow measurements in a global and qualitative way. It is proved that local normal flow measurements form global patterns in the image plane. The position of these patterns is related to the 3D motion parameters. By locating some of these patterns, which depend only on subsets of the motion parameters, through a simple search technique, the 3D motion parameters can be found. The proposed algorithmic procedure is very robust, since it is not affected by small perturbations in the normal flow measurements. The direction of translation and the axis of rotation can be estimated with up to 100% error in the image measurements %B , 1993 IEEE Computer Society Conference on Computer Vision and Pattern Recognition, 1993. Proceedings CVPR '93 %I IEEE %P 415 - 421 %8 1993/06/15/17 %@ 0-8186-3880-X %G eng %R 10.1109/CVPR.1993.341097 %0 Conference Paper %B , Proceedings of IEEE Workshop on Qualitative Vision, 1993 %D 1993 %T Motion constraint patterns %A Fermüller, Cornelia %K 3D motion parameters %K Automation %K computational geometry %K Computer vision %K correspondence %K Educational institutions %K egomotion recovery %K Fluid flow measurement %K geometric constraint %K Geometrical optics %K Image motion analysis %K image plane %K Laboratories %K local image motion %K local normal flow measurements %K Motion estimation %K Motion measurement %K motion parameters %K optical flow %K Rotation measurement %X The problem of egomotion recovery has been treated by using as input local image motion, with the published algorithms utilizing the geometric constraint relating 2-D local image motion (optical flow, correspondence, derivatives of the image flow) to 3-D motion and structure. Since it has proved very difficult to achieve accurate input (local image motion), a lot of effort has been devoted to the development of robust techniques. A new approach to the problem of egomotion estimation is taken, based on constraints of a global nature. It is proved that local normal flow measurements form global patterns in the image plane. The position of these patterns is related to the three dimensional motion parameters. By locating some of these patterns, which depend only on subsets of the motion parameters, through a simple search technique, the 3-D motion parameters can be found. The proposed algorithmic procedure is very robust, since it is not affected by small perturbations in the normal flow measurements. As a matter of fact, since only the sign of the normal flow measurement is employed, the direction of translation and the axis of rotation can be estimated with up to 100% error in the image measurements %B , Proceedings of IEEE Workshop on Qualitative Vision, 1993 %I IEEE %P 128 - 139 %8 1993/06/14/ %@ 0-8186-3692-0 %G eng %R 10.1109/WQV.1993.262942 %0 Conference Paper %B , 11th IAPR International Conference on Pattern Recognition, 1992. Vol.III. Conference C: Image, Speech and Signal Analysis, Proceedings %D 1992 %T Hierarchical curve representation %A Fermüller, Cornelia %A Kropatsch,W. %K Automation %K continuous curves %K curvature %K data mining %K digital images %K Educational institutions %K Feature extraction %K hierarchical curve representation %K IMAGE PROCESSING %K image recognition %K image resolution %K Image segmentation %K multiresolution structure %K Object recognition %K planar curves %K pyramid %K Robustness %K Sampling methods %K Smoothing methods %X Presents a robust method for describing planar curves in multiple resolution using curvature information. The method is developed by taking into account the discrete nature of digital images as well as the discrete aspect of a multiresolution structure (pyramid). The authors deal with the robustness of the technique, which is due to the additional information that is extracted from observing the behavior of corners in the pyramid. Furthermore the resulting algorithm is conceptually simple and easily parallelizable. They develop theoretical results, analyzing the curvature of continuous curves in scale-space, which show the behavior of curvature extrema under varying scale. These results are used to eliminate any ambiguities that might arise from sampling problems due to the discreteness of the representation. Finally, experimental results demonstrate the potential of the method %B , 11th IAPR International Conference on Pattern Recognition, 1992. Vol.III. Conference C: Image, Speech and Signal Analysis, Proceedings %I IEEE %P 143 - 146 %8 1992/09/30/Aug-3 %@ 0-8186-2920-7 %G eng %R 10.1109/ICPR.1992.201947 %0 Conference Paper %B Proceedings of the IEEE Workshop on Visual Motion, 1991 %D 1991 %T Relative depth from motion using normal flow: an active and purposive solution %A Huang, Liuqing %A Aloimonos, J. %K 3D information %K Automation %K Computer vision %K Educational institutions %K Image motion analysis %K image recognition %K Image sequences %K Laboratories %K Layout %K Motion analysis %K Motion estimation %K Nonlinear optics %K normal flow %K optic flow %K Optical computing %K Optical sensors %K relative depth %K retinal motion %K spatiotemporal derivatives %K time varying image intensity function %K visual motion %X The authors show how an active observer can compute the relative depth of (stationary or moving) objects in the field of view using only the spatiotemporal derivatives of the time varying image intensity function. The solution they propose is purposive in the sense that it solves only the relative depth from motion problem and cannot be used for other problems related to motion; active in the sense that the activity of the observer is essential for the solution of the problem. Results indicate that exact computation of retinal motion does not appear to be a necessary first step for some problems related to visual motion. In addition, optic flow, whose computation is an ill-posed problem, is related to the motion of the scene only under very restrictive assumptions. As a result, the use of optic flow in some quantitative motion analysis studies is questionable %B Proceedings of the IEEE Workshop on Visual Motion, 1991 %I IEEE %P 196 - 204 %8 1991/10/07/9 %@ 0-8186-2153-2 %G eng %R 10.1109/WVM.1991.212807 %0 Conference Paper %B , IEEE Conference on Visualization, 1991. Visualization '91, Proceedings %D 1991 %T Tree-maps: a space-filling approach to the visualization of hierarchical information structures %A Johnson,B. %A Shneiderman, Ben %K Computer displays %K Computer Graphics %K Computer science %K Data analysis %K display space %K Educational institutions %K Feedback %K hierarchical information structures %K HUMANS %K Laboratories %K Libraries %K Marine vehicles %K rectangular region %K semantic information %K space-filling approach %K tree-map visualization technique %K trees (mathematics) %K Two dimensional displays %K Visualization %X A method for visualizing hierarchically structured information is described. The tree-map visualization technique makes 100% use of the available display space, mapping the full hierarchy onto a rectangular region in a space-filling manner. This efficient use of space allows very large hierarchies to be displayed in their entirety and facilitates the presentation of semantic information. Tree-maps can depict both the structure and content of the hierarchy. However, the approach is best suited to hierarchies in which the content of the leaf nodes and the structure of the hierarchy are of primary importance, and the content information associated with internal nodes is largely derived from their children %B , IEEE Conference on Visualization, 1991. Visualization '91, Proceedings %I IEEE %P 284 - 291 %8 1991/10/22/25 %@ 0-8186-2245-8 %G eng %R 10.1109/VISUAL.1991.175815 %0 Conference Paper %B Workshop on Visual Motion, 1989.,Proceedings %D 1989 %T Optimal motion estimation %A Spetsakis, M. E %A Aloimonos, J. %K 3D motion interpretation %K Automation %K Computer vision %K computerised pattern recognition %K computerised picture processing %K constraint minimization %K dynamic imagery %K Educational institutions %K feature correspondences %K Gaussian noise %K Image motion analysis %K Laboratories %K maximum-likelihood-principle %K Minimization methods %K Motion analysis %K Motion estimation %K motion parameters %K moving object %K multiple frames %K nonlinear constraint %K Optical computing %K optimal motion estimation %K parameter estimation %K quadratic minimization %K quadratic programming %K redundancy %K rigidity assumption %K robotics applications %K structure-from-motion %K successive images %K two-frame %X The problem of using feature correspondences to recover the structure and 3D motion of a moving object from its successive images is analyzed. They formulate the problem as a quadratic minimization problem with a nonlinear constraint. Then they derive the condition for the solution to be optimal under the assumption of Gaussian noise in the input, in the maximum-likelihood-principle sense. The authors present two efficient ways to approximate it and discuss some inherent limitations of the structure-from-motion problem when two frames are used that should be taken into account in robotics applications that involve dynamic imagery. Finally, it is shown that some of the difficulties inherent in the two-frame approach disappear when redundancy in the data is introduced. This is concluded from experiments using a structure-from-motion algorithm that is based on multiple frames and uses only the rigidity assumption %B Workshop on Visual Motion, 1989.,Proceedings %I IEEE %P 229 - 237 %8 1989/03/20/22 %@ 0-8186-1903-1 %G eng %R 10.1109/WVM.1989.47114 %0 Conference Paper %B Proceedings of Second International Conference on Computer Vision %D 1988 %T Optimal Computing Of Structure From Motion Using Point Correspondences In Two Frames %A Spetsakis, M. E %A Aloimonos, J. %K Automation %K Computer vision %K Educational institutions %K Gaussian noise %K Image motion analysis %K Laboratories %K Least squares approximation %K Least squares methods %K Motion estimation %K Optical computing %B Proceedings of Second International Conference on Computer Vision %I IEEE %P 449 - 453 %8 1988/12/05/8 %@ 0-8186-0883-8 %G eng %R 10.1109/CCV.1988.590022 %0 Conference Paper %B 1987 IEEE International Conference on Robotics and Automation. Proceedings %D 1987 %T Determining three dimensional transformation parameters from images: Theory %A Ito, E. %A Aloimonos, J. %K Automation %K Computational modeling %K Educational institutions %K Image motion analysis %K Indium tin oxide %K Linear systems %K Motion estimation %K Optical computing %K Robots %K Simulated annealing %X We present a theory for the determination of the three dimensional transformation parameters of an object, from its images. The input to this process is the image intensity function and its temporal derivative. In particular, our results are: 1) If the structure of the transforming object in view is known, then the transformation parameters are determined from the solution of a linear system. Rigid motion is a special ease of our theory. 2)If the structure of the object in view is not known, then both the structure and transformation parameters may be computed through a hill climbing or simulated annealing algorithm. %B 1987 IEEE International Conference on Robotics and Automation. Proceedings %I IEEE %V 4 %P 57 - 61 %8 1987/03// %G eng %R 10.1109/ROBOT.1987.1088011