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Using Ssm Proxies To Provide Efficient Multiple-Source Multicast Delivery, Daniel Zappala, Aaron Fabbri Nov 2001

Using Ssm Proxies To Provide Efficient Multiple-Source Multicast Delivery, Daniel Zappala, Aaron Fabbri

Faculty Publications

We consider the possibility that single-source multicast (SSM) will become a universal multicast service, enabling large-scale distribution of content from a few well-known sources to a general audience. Operating under this assumption, we explore the problem of building the traditional IP model of any-source multicast on top of SSM. Toward this end, we design an SSM proxy service that allows any sender to efficiently deliver content to a multicast group. We demonstrate the performance improvements this service offers over standard SSM and describe extensions for access control, dynamic proxy discovery, and multicast proxy distribution.

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Modeling And Simulation Of Steady State And Transient Behaviors For Emergent Socs, Joann M. Paul, Arne Suppe, Donald E. Thomas Oct 2001

Modeling And Simulation Of Steady State And Transient Behaviors For Emergent Socs, Joann M. Paul, Arne Suppe, Donald E. Thomas

Research Collection School Of Computing and Information Systems

We introduce a formal basis for viewing computer systems as mixed steady state and non-steady state (transient) behaviors to motivate novel design strategies resulting from simultaneous consideration of function, scheduling and architecture. We relate three design styles: Hierarchical decomposition, static mapping and directed platform that have traditionally been separate. By considering them together, we reason that once a steady state system is mapped to an architecture, the unused processing and communication power may be viewed as a platform for a transient system, ultimately resulting in more effective design approaches that ease the static mapping problem while still allowing for effective …

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On Clustering And Retrieval Of Video Shots, Chong-Wah Ngo, Ting-Chuen Pong, Hong-Jiang Zhang Oct 2001

On Clustering And Retrieval Of Video Shots, Chong-Wah Ngo, Ting-Chuen Pong, Hong-Jiang Zhang

Research Collection School Of Computing and Information Systems

Clustering of video data is an important issue in video abstraction, browsing and retrieval. In this paper, we propose a two-level hierarchical clustering approach by aggregating shots with similar motion and color features. Motion features are computed directly from 20 tensor histograms, while color features are represented by 30 color histograms. Cluster validity analysis is further applied to automatically determine the number of clusters at each level. Video retrieval can then be done directly based on the result of clustering. The proposed approach is found to be useful particularly for sports games, where motion and color are important visual cues …

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Jointly Coordinating Ecn And Tcp For Rapid Adaptation To Varying Bandwidth, Archan Misra, Teunis Ott Oct 2001

Jointly Coordinating Ecn And Tcp For Rapid Adaptation To Varying Bandwidth, Archan Misra, Teunis Ott

Research Collection School Of Computing and Information Systems

The introduction of service differentiation in the Internet implies that the residual bandwidth available to best-effort traffic becomes highly variable. We explore the design of a rapidly-reactive congestion control framework, where the ECN-aware best-effort flows aggressively go after any unused capacity. By making routers mark packets in a much more aggressive manner, we are able to achieve fast backoff in the network without resorting to the TCP's current drastic step of halving the congestion window. Simulations indicate that our ECN-mod protocol is better than ECN-NewReno in exploiting rapid variations in the available bandwidth. Moreover, the milder backoff policy of ECN-mod …

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Modeling Irda Performance: The Effect Of Irlap Negotiation Parameters On Throughput, Scott V. Hansen, Charles D. Knutson, Michael G. Robertson, Franklin E. Sorenson Oct 2001

Modeling Irda Performance: The Effect Of Irlap Negotiation Parameters On Throughput, Scott V. Hansen, Charles D. Knutson, Michael G. Robertson, Franklin E. Sorenson

Faculty Publications

The Infrared Data Association's (IrDA) infrared data transmission protocol is a widely used mechanism for short-range wireless data communications. In order to provide flexibility for connections between devices of potentially disparate capabilities, IrDA devices negotiate the values of several transmission parameters based on the capabilities of the devices establishing the connection. This paper describes the design and implementation of a software tool, Irdaperf, to model IrDA performance based on negotiated transmission parameters. Using Irdaperf, we demonstrate that for fast data rates, maximizing window size and data size are key factors for overcoming the negative effects of a relatively long link …

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A Review Of Data Mining Techniques, Sang Jun Lee, Keng Siau Oct 2001

A Review Of Data Mining Techniques, Sang Jun Lee, Keng Siau

Research Collection School Of Computing and Information Systems

Terabytes of data are generated everyday in many organizations. To extract hidden predictive information from large volumes of data, data mining (DM) techniques are needed. Organizations are starting to realize the importance of data mining in their strategic planning and successful application of DM techniques can be an enormous payoff for the organizations. This paper discusses the requirements and challenges of DM, and describes major DM techniques such as statistics, artificial intelligence, decision tree approach, genetic algorithm, and visualization.

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Integrating Color And Spatial Features For Content-Based Video Retrieval, Tong Lin, Chong-Wah Ngo, Hong-Jiang Zhang, Qing-Yun Shi Oct 2001

Integrating Color And Spatial Features For Content-Based Video Retrieval, Tong Lin, Chong-Wah Ngo, Hong-Jiang Zhang, Qing-Yun Shi

Research Collection School Of Computing and Information Systems

In this paper, we present a novel and efficient scheme for extracting, indexing and retrieving color images. Our motivation was to reduce the space overhead of partition-based approaches taking advantage of the fact that only a relatively low number of distinct values of a particular visual feature is present in most images. To extract color feature and build indices into our image database we take into consideration factors such as human color perception and perceptual range, and the image is partitioned into a set of regions by using a simple classifying scheme. The compact color feature vector and the spatial …

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Mining Multi-Level Rules With Recurrent Items Using Fp'-Tree, Kok-Leong Ong, Wee-Keong Ng, Ee Peng Lim Oct 2001

Mining Multi-Level Rules With Recurrent Items Using Fp'-Tree, Kok-Leong Ong, Wee-Keong Ng, Ee Peng Lim

Research Collection School Of Computing and Information Systems

Association rule mining has received broad research in the academic and wide application in the real world. As a result, many variations exist and one such variant is the mining of multi-level rules. The mining of multi-level rules has proved to be useful in discovering important knowledge that conventional algorithms such as Apriori, SETM, DIC etc., miss. However, existing techniques for mining multi-level rules have failed to take into account the recurrence relationship that can occur in a transaction during the translation of an atomic item to a higher level representation. As a result, rules containing recurrent items go unnoticed. …

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Hierarchical Mobility Management For Voip Traffic, Archan Misra, Subir Das, Anthony J. Mcauley Oct 2001

Hierarchical Mobility Management For Voip Traffic, Archan Misra, Subir Das, Anthony J. Mcauley

Research Collection School Of Computing and Information Systems

A hierarchical IP-based mobility management mechanism is proposed for VoIP applications. The suggested mechanism uses the DMA (dynamic mobility agent) architecture, based on IDMP (intra-domain mobility management protocol), for managing intra-domain mobility and the dynamic binding mechanism of SIP (session initiation protocol) for managing global mobility. This combination of network and application layer mobility management reduces the global signaling load, provides fast handoff for ongoing conversations, enables efficient global transport and supports IP-layer paging.

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A Transaction Model To Improve Data Availability In Mobile Computing, Sanjay Kumar Madria, Bharat Bhargava Sep 2001

A Transaction Model To Improve Data Availability In Mobile Computing, Sanjay Kumar Madria, Bharat Bhargava

Computer Science Faculty Research & Creative Works

We incorporate a prewrite operation before a write operation in a mobile transaction to improve data availability. A prewrite operation does not update the state of a data object but only makes visible the future value that the data object will have after the final commit of the transaction. Once a transaction reads all the values and declares all the prewrites, it can pre-commit at mobile host (MH) (computer connected to unreliable mobile communication network). The remaining transaction's execution (writes on database) is shifted to the mobile service station (MSS) (computer connected to the reliable fixed network). Writes on database …

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Online Bayesian Tree-Structured Transformation Of Hmms With Optimal Model Selection For Speaker Adaptation, Shaojun Wang, Yunxin Zhao Sep 2001

Online Bayesian Tree-Structured Transformation Of Hmms With Optimal Model Selection For Speaker Adaptation, Shaojun Wang, Yunxin Zhao

Kno.e.sis Publications

This paper presents a new recursive Bayesian learning approach for transformation parameter estimation in speaker adaptation. Our goal is to incrementally transform or adapt a set of hidden Markov model (HMM) parameters for a new speaker and gain large performance improvement from a small amount of adaptation data. By constructing a clustering tree of HMM Gaussian mixture components, the linear regression (LR) or affine transformation parameters for HMM Gaussian mixture components are dynamically searched. An online Bayesian learning technique is proposed for recursive maximum a posteriori (MAP) estimation of LR and affine transformation parameters. This technique has the advantages of …

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Nonparametric Techniques To Extract Fuzzy Rules For Breast Cancer Diagnosis Problem, Manish Sarkar, Tze-Yun Leong Sep 2001

Nonparametric Techniques To Extract Fuzzy Rules For Breast Cancer Diagnosis Problem, Manish Sarkar, Tze-Yun Leong

Research Collection School Of Computing and Information Systems

This paper addresses breast cancer diagnosis problem as a pattern classification problem. Specifically, the problem is studied using Wisconsin-Madison breast cancer data set. Fuzzy rules are generated from the input-output relationship so that the diagnosis becomes easier and transparent for both patients and physicians. For each class, at least one training pattern is chosen as the prototype, provided (a) the maximum membership of the training pattern is in the given class, and (b) among all the training patterns, the neighborhood of this training pattern has the least fuzzy-rough uncertainty in the given class. Using the fuzzy-rough uncertainty, a cluster is …

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Exploiting Image Indexing Techniques In Dct Domain, Chong-Wah Ngo, Ting-Chuen Pong, Ronald T. Chin Sep 2001

Exploiting Image Indexing Techniques In Dct Domain, Chong-Wah Ngo, Ting-Chuen Pong, Ronald T. Chin

Research Collection School Of Computing and Information Systems

This paper is concerned with the indexing and retrieval of images based on features extracted directly from the JPEG discrete cosine transform (DCT) domain. We examine possible ways of manipulating DCT coefficients by standard image analysis approaches to describe image shape, texture, and color. Through the Mandala transformation, our approach groups a subset of DCT coefficients to form ten blocks. Each block represents a particular frequency content of the original image. Two blocks are used to model rough object shape; nine blocks to describe subband properties; and one block to compute color distribution. As a result, the amount of data …

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Improving Cluster Utilization Through Set Based Allocation Policies, Quinn O. Snell, Julio C. Facelli, Brian D. Haymore, David B. Jackson Sep 2001

Improving Cluster Utilization Through Set Based Allocation Policies, Quinn O. Snell, Julio C. Facelli, Brian D. Haymore, David B. Jackson

Faculty Publications

While clusters have already proven themselves in the world of high performance computing, some clusters are beginning to exhibit resource inefficiencies due to increasing hardware diversity. Much of the success of clusters lies in the use of commodity components built to meet various hardware standards. These standards have allowed a great level of hardware backwards compatibility that is now resulting in a condition referred to as hardware 'drift' or heterogeneity. The hardware heterogeneity introduces problems when diverse compute nodes are allocated to a parallel job, as most parallel jobs are not self-balancing. This paper presents a new method that allows …

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Vide: A Visual Data Extraction Environment For The Web, Yi Li, Wee-Keong Ng, Ee Peng Lim Sep 2001

Vide: A Visual Data Extraction Environment For The Web, Yi Li, Wee-Keong Ng, Ee Peng Lim

Research Collection School Of Computing and Information Systems

With the rapid growth of information on the Web, a means to combat information overload is critical. In this paper, we present ViDE (Visual Data Extraction), an interactive web data extraction environment that supports efficient hierarchical data wrapping of multiple web pages. ViDE has two unique features that differentiate it from other extraction mechanisms. First, data extraction rules can be easily specified in a graphical user interface that is seamlessly integrated with a web browser. Second, ViDE introduces the concept of grouping which unites the extraction rules for a set of documents with the navigational patterns that exist among them. …

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Livelock Avoidance For Meta-Schedulers, Mark J. Clement, John Jardine, Quinn O. Snell Aug 2001

Livelock Avoidance For Meta-Schedulers, Mark J. Clement, John Jardine, Quinn O. Snell

Faculty Publications

Meta-scheduling, a process which allows a user to schedule a job across multiple sites, has a potential for livelock. Current systems avoid livelock by locking down resources at multiple sites and allowing a metascheduler to control the resources during the lock down period or by limiting job size to that which will fit on one site. The former approach leads to poor utilization; the later poses limitations on job size. This research uses BYU's Meta-scheduler (YMS) which allows jobs to be scheduled across multiple sites without the need for locking down the nodes. YMS avoids livelock through exponential back-off This …

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A Method For Fast Revocation Of Public Key Certificates And Security Capabilities, D. Boneh, Xuhua Ding, Gene Tsudik, Chi Ming Wong Aug 2001

A Method For Fast Revocation Of Public Key Certificates And Security Capabilities, D. Boneh, Xuhua Ding, Gene Tsudik, Chi Ming Wong

Research Collection School Of Computing and Information Systems

We present a new approach to fast certificate revocation centered around the concept of an on-line semi-trusted mediator (SEM). The use of a SEM in conjunction with a simple threshold variant of the RSA cryptosystem (mediated RSA) offers a number of practical advantages over current revocation techniques. Our approach simplifies validation of digital signatures and enables certificate revocation within legacy systems. It also provides immediate revocation of all security capabilities. This paper discusses both the architecture and implementation of our approach as well as performance and compatibility with the existing infrastructure. Our results show that threshold cryptography is practical for …

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Generating Market Basket Data With Temporal Information, Yingjiu Li, Peng Ning, X. Sean Wang, Sushil Jajodia Aug 2001

Generating Market Basket Data With Temporal Information, Yingjiu Li, Peng Ning, X. Sean Wang, Sushil Jajodia

Research Collection School Of Computing and Information Systems

This paper presents a synthetic data generator that outputs timestamped transactional data with embedded temporal patterns controlled by a set of input parameters. In particular, calendar schema, which is determined by a hierarchy of input time granularities, is used as a framework of possible temporal patterns. An example of calendar schema is (year, month, day), which provides a framework for calendar-based temporal patterns of the form -38352 , where each is either an integer or the symbol . For example, is such a pattern, which corresponds to the time intervals consisting of all the 16th days of all months in …

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Role Of Use Case Diagram In Requirement Analysis, Keng Siau, L. Lee Aug 2001

Role Of Use Case Diagram In Requirement Analysis, Keng Siau, L. Lee

Research Collection School Of Computing and Information Systems

Since its debut and acceptance as a de facto standard of the object-oriented paradigm, UML has receivedcontroversial reviews. The most controversial diagramming technique in UML is undoubtedly the Use Casediagrams. Some claim that Use Case diagrams do not play a valuable role in requirement analysis. Othersargue that Use Case diagrams captured neither the static nor the dynamic aspects of the systems. The objective of this study is to investigate the role and value of Use Case diagrams in requirement analysis. We will investigate the information content of Use Case diagram and its role in requirement analysis.

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An Integrated Model On Computer Abuse: A Pilot Study, S. G. Lee, Fiona Fui-Hoon Nah, S. Yoo Aug 2001

An Integrated Model On Computer Abuse: A Pilot Study, S. G. Lee, Fiona Fui-Hoon Nah, S. Yoo

Research Collection School Of Computing and Information Systems

In spite of continuous organizational efforts and investments based on systematic factors, the incidence of computer abuse in organizations is still rapidly increasing. This paper proposes another perspective -- based on the general strain theory -- in preventing computer abuse. According to the general strain theory, organizational trust, which comprises organizational attachment, commitment, involvement, and norms, can prevent computer abuse by reducing insidersí computer abuse. The aim of this article is to assess the role of organizational trust from the perspectives of attachment, commitment, involvement, and norms in preventing computer abuse. The results indicate that both organizational trust and deterrent …

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Real-Time Travel Time Estimation Using Macroscopic Traffic Flow Models, Pushkin Kachroo, Kaan Ozbay, Antoine G. Hobeika Aug 2001

Real-Time Travel Time Estimation Using Macroscopic Traffic Flow Models, Pushkin Kachroo, Kaan Ozbay, Antoine G. Hobeika

Electrical & Computer Engineering Faculty Research

This paper presents the estimation of travel time on highways based on macroscopic modelling. The focus is on real-time values as compared to average or static values. The macroscopic models are used for distributed and time/space lumped settings and corresponding travel time estimation functions and algorithms are developed. The implications of these algorithms for the implementation of various incident management and traffic control strategies are also discussed.

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Analysis Of A New Vehicle Scheduling And Location Problem, Ebru K. Bish, Thin Yin Leong, Chun-Lun Li, Jonathan W. C. Ng, David Simchi-Levi Aug 2001

Analysis Of A New Vehicle Scheduling And Location Problem, Ebru K. Bish, Thin Yin Leong, Chun-Lun Li, Jonathan W. C. Ng, David Simchi-Levi

Research Collection School Of Computing and Information Systems

We consider a container terminal discharging containers from a ship and locating them in the terminal yard. Each container has a number of potential locations in the yard where it can be stored. Containers are moved from the ship to the yard using a fleet of vehicles, each of which can carry one container at a time. The problem is to assign each container to a yard location and dispatch vehicles to the containers so as to minimize the time it takes to download all the containers from the ship. We show that the problem is NP-hard and develop a …

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Research Issues In Human-Computer Interaction In The Web-Based Environment, Fiona Fui-Hoon Nah, Sid Davis Aug 2001

Research Issues In Human-Computer Interaction In The Web-Based Environment, Fiona Fui-Hoon Nah, Sid Davis

Research Collection School Of Computing and Information Systems

The Internet and WWW are revolutionizing our daily lives and the way business is conducted. Since 1997, the Web has gradually evolved into a true economy and a new frontier for business. In this new Internet age, the design of a quality Web site is critical to the success of businesses. To attract and retain visitors, Web sites need to be human-centered, easy and quick to navigate, and speak the visitor’s language. User experience with the Web site is also important. The experience should be in line with the user’s goal and should feel natural to the user. Unfortunately, principles …

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Video Partitioning By Temporal Slice Coherency, Chong-Wah Ngo, Ting-Chuen Pong, Roland T. Chin Aug 2001

Video Partitioning By Temporal Slice Coherency, Chong-Wah Ngo, Ting-Chuen Pong, Roland T. Chin

Research Collection School Of Computing and Information Systems

We present a novel approach for video partitioning by detecting three essential types of camera breaks, namely cuts, wipes, and dissolves. The approach is based on the analysis of temporal slices which are extracted from the video by slicing through the sequence of video frames and collecting temporal signatures. Each of these slices contains both spatial and temporal information from which coherent regions are indicative of uninterrupted video partitions separated by camera breaks. Properties could further be extracted from the slice for both the detection and classification of camera breaks. For example, cut and wipes are detected by color-texture properties, …

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A Multi-Agent Framework For Supporting Intelligent Fourth-Party Logistics, Hoong Chuin Lau, G. Lo Aug 2001

A Multi-Agent Framework For Supporting Intelligent Fourth-Party Logistics, Hoong Chuin Lau, G. Lo

Research Collection School Of Computing and Information Systems

A distributed intelligent agent-based framework that supports fourth-party logistics optimization under a web-based e-Commerce environment has been proposed in this paper. In the framework, customer job requests come through an e-Procurement service. These requests are consolidated and pushed to the e-Market Place service periodically. The e-Market Place then serves as a broker that allows intelligent agents to bid to serve these requests optimally in real-time by solving multiple instances of underlying logistics optimization problem. The resulting system was implemented based on the Java 2 Enterprise Edition (J2EE) platform using distributed system technology for communication between objects.

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Autoconfiguration, Registration And Mobility Management For Pervasive Computing, Archan Misra, Subir Das, Anthony Mcauley, Sajal K. Das Aug 2001

Autoconfiguration, Registration And Mobility Management For Pervasive Computing, Archan Misra, Subir Das, Anthony Mcauley, Sajal K. Das

Research Collection School Of Computing and Information Systems

In the vision of pervasive computing, users will exchange information and control their environments from anywhere using various wireline/wireless networks and computing devices. We believe that current protocols, such as DHCP, PPP, and Mobile IP, must be enhanced to support pervasive network access. In particular, this article identifies three fundamental functions: autoconfiguration, registration, and mobility management, that need such enhancements. Realizing that the IP autoconfiguration capabilities must be extended to configure routers and large dynamic networks, we first describe our autoconfiguration solution based on the dynamic configuration and distribution protocol (DCDP). Second, we discuss why providing user-specific services over a …

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The Need For Small Learning Rates On Large Problems, Tony R. Martinez, D. Randall Wilson Jul 2001

The Need For Small Learning Rates On Large Problems, Tony R. Martinez, D. Randall Wilson

Faculty Publications

In gradient descent learning algorithms such as error backpropagation, the learning rate parameter can have a significant effect on generalization accuracy. In particular, decreasing the learning rate below that which yields the fastest convergence can significantly improve generalization accuracy, especially on large, complex problems. The learning rate also directly affects training speed, but not necessarily in the way that many people expect. Many neural network practitioners currently attempt to use the largest learning rate that still allows for convergence, in order to improve training speed. However, a learning rate that is too large can be as slow as a learning …

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Optimal Artificial Neural Network Architecture Selection For Bagging, Timothy L. Andersen, Tony R. Martinez, Michael E. Rimer Jul 2001

Optimal Artificial Neural Network Architecture Selection For Bagging, Timothy L. Andersen, Tony R. Martinez, Michael E. Rimer

Faculty Publications

This paper studies the performance of standard architecture selection strategies, such as cost/performance and CV based strategies, for voting methods such as bagging. It is shown that standard architecture selection strategies are not optimal for voting methods and tend to underestimate the complexity of the optimal network architecture, since they only examine the performance of the network on an individual basis and do not consider the correlation between responses from multiple networks.

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Improved Hopfield Networks By Training With Noisy Data, Fred Clift, Tony R. Martinez Jul 2001

Improved Hopfield Networks By Training With Noisy Data, Fred Clift, Tony R. Martinez

Faculty Publications

A new approach to training a generalized Hopfield network is developed and evaluated in this work. Both the weight symmetricity constraint and the zero self-connection constraint are removed from standard Hopfield networks. Training is accomplished with Back-Propagation Through Time, using noisy versions of the memorized patterns. Training in this way is referred to as Noisy Associative Training (NAT). Performance of NAT is evaluated on both random and correlated data. NAT has been tested on several data sets, with a large number of training runs for each experiment. The data sets used include uniformly distributed random data and several data sets …

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Speed Training: Improving The Rate Of Backpropagation Learning Through Stochastic Sample Presentation, Timothy L. Andersen, Tony R. Martinez, Michael E. Rimer Jul 2001

Speed Training: Improving The Rate Of Backpropagation Learning Through Stochastic Sample Presentation, Timothy L. Andersen, Tony R. Martinez, Michael E. Rimer

Faculty Publications

Artificial neural networks provide an effective empirical predictive model for pattern classification. However, using complex neural networks to learn very large training sets is often problematic, imposing prohibitive time constraints on the training process. We present four practical methods for dramatically decreasing training time through dynamic stochastic sample presentation, a technique we call speed training. These methods are shown to be robust to retaining generalization accuracy over a diverse collection of real world data sets. In particular, the SET technique achieves a training speedup of 4278% on a large OCR database with no detectable loss in generalization.

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