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From 2006 (Clear Search)

2006
Publication Details
  • Henry Hexmoor, Marcin Paprzycki, Niranjan Suri (eds) Scalable Computing: Practice and Experience Volume 7, No. 4, December 2006
  • Dec 23, 2006

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Current search engines crawl the Web, download content, and digest this content locally. For multimedia content, this involves considerable volumes of data. Furthermore, this process covers only publicly available content because content providers are concerned that they otherwise loose control over the distribution of their intellectual property. We present the prototype of our secure and distributed search engine, which dynamically pushes content based feature extraction to image providers. Thereby, the volume of data that is transported over the network is significantly reduced, and the concerns mentioned above are alleviated. The distribution of feature extraction and matching algorithms is done by mobile software agents. Subsequent search requests performed upon the resulting feature indices by means of remote feature comparison can either be realized through mobile software agents, or by the use of implicitly created Web services which wrap the remote comparison functionality, and thereby improve the interoperability of the search engine. We give a description of the search engine's architecture and implementation, depict our concepts to integrate agent and Web service technology, and present quantitative evaluation results. Furthermore, we discuss related security mechanisms for content protection and server security.

Security Risks in Java-based Mobile Code Systems

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  • Henry Hexmoor, Marcin Paprzycki, Niranjan Suri (eds) Scalable Computing: Practice and Experience Volume 7, No. 4, December 2006
  • Dec 23, 2006

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Java is the predominant language for mobile agent systems, both for implementing mobile agent execution environments and for writing mobile agent applications. This is due to inherent support for code mobility by means of dynamic class loading and separable class name spaces, as well as a number of security properties, such as language safety and access control by means of stack introspection. However, serious questions must be raised whether Java is actually up to the task of providing a secure execution environment for mobile agents. At the time of writing, it has neither resource control nor proper application separation. In this article we take an in-depth look at Java as a foundation for secure mobile agent systems.
Publication Details
  • MobCops 2006 Workshop in conjunction with IEEE/ACM CollaborateCom 2006, Atlanta, Georgia, USA.
  • Nov 17, 2006

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Load balancing has been an increasingly important issue for handling computational intensive tasks in a distributed system such as in Grid and cluster computing. In such systems, multiple server instances are installed for handling requests from client applications, and each request (or task) typically needs to stay in a queue before an available server is assigned to process it. In this paper, we propose a high-performance queueing method for implementing a shared queue for collaborative clusters of servers. Each cluster of servers maintains a local queue and queues of different clusters are networked to form a unified (or shared) queue that may dispatch tasks to all available servers. We propose a new randomized algorithm for forwarding requests in an overcrowded local queue to a networked queue based on load information of the local and neighboring clusters. The algorithm achieves both load balancing and locality awareness.

Term Context Models for Information Retrieval

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  • CIKM (Conference on information and Knowledge Management) 2006, Arlington, VA
  • Nov 7, 2006

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At their heart, most if not all information retrieval models utilize some form of term frequency. The notion is that the more often a query term occurs in a document, the more likely it is that document meets an information need. We examine an alternative. We propose a model which assesses the presence of a term in a document not by looking at the actual occurrence of that term, but by a set of nonindependent supporting terms, i.e. context. This yields a weighting for terms in documents which is different from and complementary to tf-based methods, and is beneficial for retrieval.
Publication Details
  • In Proceedings of the fourth ACM International Workshop on Video Surveillance & Sensor Networks VSSN '06, Santa Barbara, CA, pp. 19-26
  • Oct 27, 2006

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Video surveillance systems have become common across a wide number of environments. While these installations have included more video streams, they also have been placed in contexts with limited personnel for monitoring the video feeds. In such settings, limited human attention, combined with the quantity of video, makes it difficult for security personnel to identify activities of interest and determine interrelationships between activities in different video streams. We have developed applications to support security personnel both in analyzing previously recorded video and in monitoring live video streams. For recorded video, we created storyboard visualizations that emphasize the most important activity as heuristically determined by the system. We also developed an interactive multi-channel video player application that connects camera views to map locations, alerts users to unusual and suspicious video, and visualizes unusual events along a timeline for later replay. We use different analysis techniques to determine unusual events and to highlight them in video images. These tools aid security personnel by directing their attention to the most important activity within recorded video or among several live video streams.
Publication Details
  • UIST 2006 Companion
  • Oct 16, 2006

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Video surveillance requires keeping the human in the loop. Software can aid security personnel in monitoring and using video. We have developed a set of interface components designed to locate and follow important activity within security video. By recognizing and visualizing localized activity, presenting overviews of activity over time, and temporally and geographically contextualizing video playback, we aim to support security personnel in making use of the growing quantity of security video.
Publication Details
  • UIST 2006 Companion
  • Oct 16, 2006

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With the growing quantity of security video, it becomes vital that video surveillance software be able to support security personnel in monitoring and tracking activities. We have developed a multi-stream video player that plays recorded and live videos while drawing the users' attention to activity in the video. We will demonstrate the features of the video player and in particular, how it focuses on keeping the human in the loop and drawing their attention to activities in the video.
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  • Proceedings of IEEE Multimedia Signal Processing 2006
  • Oct 3, 2006

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This paper presents a method for facilitating document redirection in a physical environment via a mobile camera. With this method, a user is able to move documents among electronic devices, post a paper document to a selected public display, or make a printout of a white board with simple point-and-capture operations. More specifically, the user can move a document from its source to a destination by capturing a source image and a destination image in a consecutive order. The system uses SIFT (Scale Invariant Feature Transform) features of captured images to identify the devices a user is pointing to, and issues corresponding commands associated with identified devices. Unlike RF/IR based remote controls, this method uses object visual features as an all time 'transmitter' for many tasks, and therefore is easy to deploy. We present experiments on identifying three public displays and a document scanner in a conference room for evaluation.

The USE Project: Designing Smart Spaces for Real People

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  • UbiComp 2006 Workshop position paper
  • Sep 20, 2006

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We describe our work-in-progress: a "wizard-free" conference room designed for ease of use, yet retaining next-generation functionality. Called USE (Usable Smart Environments), our system uses multi-display systems, immersive conferencing, and secure authentication. It is based in cross-cultural ethnographic studies on the way people use conference rooms. The USE project has developed a flexible, extensible architecture specifically designed to enhance ease of use in smart environment technologies. The architecture allows customization and personalization of smart environments for particular people and groups, types of work, and specific physical spaces. The system consists of a database of devices with attributes, rooms and meetings that implements a prototype-instance inheritance mechanism through which contextual information (e.g. IP addresses application settings, phone numbers for teleconferencing systems, etc.) can be associated

Usable ubiquitous computing in next generation conference rooms: design, architecture and evaluation

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  • International workshop at UbiComp 2006.
  • Sep 17, 2006

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In the UbiComp 2005 workshop "Ubiquitous computing in next generation conference rooms" we learned that usability is one of the primary challenges in these spaces. Nearly all "smart" rooms, though they often have interesting and effective functionality, are very difficult to simply walk in and use. Most such rooms have resident experts who keep the room's systems functioning, and who often must be available on an everyday basis to enable the meeting technologies. The systems in these rooms are designed for and assume the presence of these human "wizards"; they are seldom designed with usability in mind. In addition, people don't know what to expect in these rooms; as yet there is no technology standard for next-generation conference rooms. The challenge here is to strike an effective balance between usability and new kinds of functionality (such as multiple displays, new interfaces, rich media systems, new uploading/access/security systems, robust mobile integration, to name just a few of the functions we saw in last year's workshop). So, this year, we propose a workshop to focus more specifically on how the design of next-generation conference rooms can support usability: the tasks facing the real people who use these rooms daily. Usability in ubiquitous computing has been the topic of several papers and workshops. Focusing on usability in next-generation conference rooms lets us bring to bear some of the insights from this prior work in a delineated application space. In addition the workshop will be informed by the most recent usability research in ubiquitous computing, rich media, context-aware mobile systems, multiple display environments, and interactive physical environments. We also are vitally concerned with how usability in smart environments tracks (or doesn't) across cultures. Conference room research has been and remains a focal point for some of the most interesting and applied work in ubiquitous computing. It is also an area where there are many real-world applications and daily opportunities for user feed-back: in short, a rich area for exploring usable ubiquitous computing. We see a rich opportunity to draw together researchers not only from conference room research but also from areas such as interactive furniture/smart environments, rich media, social computing, remote conferencing, and mobile devices for a lively exchange of ideas on usability in applied ubicomp systems for conference rooms.
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  • International Conference on Pattern Recognition
  • Aug 20, 2006

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This paper describes a framework for detecting unusual events in surveillance videos. Most surveillance systems consist of multiple video streams, but traditional event detection systems treat individual video streams independently or combine them in the feature extraction level through geometric reconstruction. Our framework combines multiple video streams in the inference level, with a coupled hidden Markov Model (CHMM). We use two-stage training to bootstrap a set of usual events, and train a CHMM over the set. By thresholding the likelihood of a test segment being generated by the model, we build a unusual event detector. We evaluate the performance of our detector through qualitative and quantitative experiments on two sets of real world videos.
Publication Details
  • Interactive Video; Algorithms and Technologies Hammoud, Riad (Ed.) 2006, XVI, 250 p., 109 illus., Hardcover.
  • Jun 7, 2006

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This chapter describes tools for browsing and searching through video to enable users to quickly locate video passages of interest. Digital video databases containing large numbers of video programs ranging from several minutes to several hours in length are becoming increasingly common. In many cases, it is not sufficient to search for relevant videos, but rather to identify relevant clips, typically less than one minute in length, within the videos. We offer two approaches for finding information in videos. The first approach provides an automatically generated interactive multi-level summary in the form of a hypervideo. When viewing a sequence of short video clips, the user can obtain more detail on the clip being watched. For situations where browsing is impractical, we present a video search system with a flexible user interface that incorporates dynamic visualizations of the underlying multimedia objects. The system employs automatic story segmentation, and displays the results of text and image-based queries in ranked sets of story summaries. Both approaches help users to quickly drill down to potentially relevant video clips and to determine the relevance by visually inspecting the material.

Visualization in Audio-Based Music Information Retrieval

Publication Details
  • Computer Music Journal Vol. 30, Issue 2, pp. 42-62, 2006.
  • Jun 6, 2006

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Music Information Retrieval (MIR) is an emerging research area that explores how music stored digitally can be effectively organized, searched, retrieved and browsed. The explosive growth of online music distribution, portable music players and lowering costs of recording indicate that in the near future most of recorded music in human history will be available digitally. MIR is steadily growing as a research area as can be evidenced by the international conference on music information retrieval (ISMIR) series soon in its sixth year and the increasing number of MIR-related publications in the Computer Music Journal as well as other journals and conferences.
Publication Details
  • Complexity, Vol 11, No 5.
  • Jun 3, 2006

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Technology-the collection of devices and methods available to human society-evolves by constructing new devices and methods from ones that previously exist, and in turn offering these as possible components-building blocks-for the construction of further new devices and elements. The collective of technology in this way forms a network of elements where novel elements are created from existing ones and where more complicated elements evolve from simpler ones. We model this evolution within a simple artificial system on the computer. The elements in our system are logic circuits. New elements are formed by combination from simpler existing elements (circuits), and if a novel combination satisfies one of a set of needs it is retained as a building block for further combination. We study the properties of the resulting buildout. We find that our artificial system can create complicated technologies (circuits), but only by first creating simpler ones as building blocks. Our results mirror Lenski et al.'s, that complex features can be created in biological evolution only if simpler functions are first favored and act as stepping stones. We also find evidence that the resulting collection of technologies exists at self-organized criticality.
Publication Details
  • Proceedings of AVI '06 (Short Paper), ACM Press, pp. 258-261.
  • May 23, 2006

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During grouping tasks for data exploration and sense-making, the criteria are normally not well-defined. When users are bringing together data objects thought to be similar in some way, implicit brushing continually detects for groups on the freeform workspace, analyzes the groups' text content or metadata, and draws attention to related data by displaying visual hints and animation. This provides helpful tips for further grouping, group meaning refinement and structure discovery. The sense-making process is further enhanced by retrieving relevant information from a database or network during the brushing. Closely related to implicit brushing, target snapping provides a useful means to move a data object to one of its related groups on a large display. Natural dynamics and smooth animations also help to prevent distractions and allow users to concentrate on the grouping and thinking tasks. Two different prototype applications, note grouping for brainstorming and photo browsing, demonstrate the general applicability of the technique.
Publication Details
  • The 15th International World Wide Web Conference (WWW2006)
  • May 23, 2006

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In a landmark article, over a half century ago, Vannevar Bush envisioned a "Memory Extender" device he dubbed the "memex". Bush's ideas anticipated and inspired numerous breakthroughs, including hypertext, the Internet, the World Wide Web, and Wikipedia. However, despite these triumphs, the memex has still not lived up to its potential in corporate settings. One reason is that corporate users often don't have sufficient time or incentives to contribute to a corporate memory or to explore others' contributions. At FXPAL, we are investigating ways to automatically create and retrieve useful corporate memories without any added burden on anyone. In this paper we discuss how ProjectorBox a smart appliance for automatic presentation capture and PAL Bar a system for proactively retrieving contextually relevant corporate memories have enabled us to integrate content from a variety of sources to create a cohesive multimedia corporate memory for our organization.

Tunnel Vector: A New Routing Algorithm with Scalability

Publication Details
  • The 9th IEEE Global Internet Symposium in conjunction with the 25th IEEE INFOCOM Conference, Barcelona, Catalunya, Spain, April 28 - 29, 2006
  • Apr 28, 2006

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Routing algorithms such as Distance Vector and Link States have the routing table size as O(n), where n is the number of destination identifiers, thus providing only limited scalability for large networks when n is high. As the distributed hash table (DHT) techniques are extraordinarily scalable with n, our work aims at adapting a DHT approach to the design of a network-layer routing algorithm so that the average routing table size can be significantly reduced to O(log n) without losing much routing efficiency. Nonetheless, this scheme requires a major breakthrough to address some fundamental challenges. Specifically, unlike a DHT, a network-layer routing algorithm must (1) exchange its control messages without an underlying network, (2) handle link insertion/deletion and link-cost updates, and (3) provide routing efficiency. Thus, we are motivated to propose a new network-layer routing algorithm, Tunnel Vector (TV), using DHT-like multilevel routing without an underlying network. TV exchanges its control messages only via physical links and is self-configurable in response to linkage updates. In TV, the routing path of a packet is near optimal while the routing table size is O(log n) per node, with high probability. Thus, TV is suitable for routing in a very large network.
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  • Proceedings of ACM DIS (Designing Interactive Systems) 2006, Penn State, Penn.
  • Apr 5, 2006

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What does a student need to know to be a designer? Beyond a list of separate skills, what mindset does a student need to develop for designerly action now and into the future? In the excitement of the cognitive revolution, Simon proposed a way of thinking about design that promised to make it more manageable and cognitive: to think of design as a planning problem. Yet, as Suchman argued long ago, planning accounts may be applied to problems that are not at base accomplished by planning, to the detriment of design vision. This paper reports on a pedagogy that takes Suchman's criticism to heart and avoids dressing up design methods as more systematic and predictive than they in fact are. The idea is to teach design through expo-sure to not just one, but rather, many methods---that is, sets of rules or behaviors that produce artifacts for further reflec-tion and development. By introducing a large number of design methods, decoupled from theories, models or frame-works, we teach (a) important cross-methodological regu-larities in competence as a designer, (b) that the practice of design can itself be designed and (c) that method choice affects design outcomes. This provides a rich and produc-tive notion of design particularly necessary for the world of pervasive and ubiquitous computing.
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  • EACL (11th Conference of the European Chapter of the Association for Computational Linguistics)
  • Apr 3, 2006

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Probabilistic Latent Semantic Analysis (PLSA) models have been shown to provide a better model for capturing polysemy and synonymy than Latent Semantic Analysis (LSA). However, the parameters of a PLSA model are trained using the Expectation Maximization (EM) algorithm, and as a result, the trained model is dependent on the initialization values so that performance can be highly variable. In this paper we present a method for using LSA analysis to initialize a PLSA model. We also investigated the performance of our method for the tasks of text segmentation and retrieval on personal-size corpora, and present results demonstrating the efficacy of our proposed approach.
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  • International Journal of Web Services Practices
  • Jan 17, 2006

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Mobile users often require access to their documents while away from the office. While pre-loading documents in a repository can make those documents available remotely, people need to know in advance which documents they might need. Furthermore, it may be difficult to view, print, or share the document through a portable device such as cell phone. We describe DoKumobility, a network of web services for mobile users for managing, printing, and sharing documents. In this paper, we describe the infrastructure and illustrate its use with several applications. We conclude with a discussion of lessons learned and future work.