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Motion Tracking Of Human Mouth By Generalized Deformable Models, Syin Chan, Chong-Wah Ngo, Kok F. Lai Sep 1999

Motion Tracking Of Human Mouth By Generalized Deformable Models, Syin Chan, Chong-Wah Ngo, Kok F. Lai

Research Collection School Of Computing and Information Systems

We propose and evaluate four trackers for tracking the shape, motion and deformation of a human mouth in video sequences. The trackers are suitable for use in very low bitrate video coding systems. (C) 1999 Elsevier Science B.V. All rights reserved.


Qos Scalability For Streamed Media Delivery, Charles Krasic, Jonathan Walpole Sep 1999

Qos Scalability For Streamed Media Delivery, Charles Krasic, Jonathan Walpole

Computer Science Faculty Publications and Presentations

Applications with real-rate progress requirements, such as mediastreaming systems, are difficult to deploy in shared heterogenous environments such as the Internet. On the Internet, mediastreaming systems must be capable of trading off resource requirements against the quality of the media streams they deliver, in order to match wide-ranging dynamic variations in bandwidth between servers and clients. Since quality requirements tend to be user- and task-specific, mechanisms for capturing quality of service requirements and mapping them to appropriate resource-level adaptation policies are required. In this paper, we describe a general approach for automatically mapping user-level quality of service specifications onto resource …


Design Approaches To Model-Based Simulation In Intelligent Computer Assisted Instruction, Bjoern Helfesrieder, Venky Shankararaman Sep 1999

Design Approaches To Model-Based Simulation In Intelligent Computer Assisted Instruction, Bjoern Helfesrieder, Venky Shankararaman

Research Collection School Of Computing and Information Systems

Model-based simulation systems have been created in various fields of engineering to train personnel or students in operation, maintenance and troubleshooting of complex devices and systems. A review of literature indicates a lack of good overviews of the approaches to system design of model-based training simulations in Intelligent Computer Assisted Instruction (ICAI). Though single systems have to some extent been evaluated with regard to their performance, an organised evaluation, especially a comparative evaluation of the systems that have been created within the field is lacking. To be able to successfully conduct an in-depth review under these conditions, we concentrate and …


Teaching Operating System Concepts Using Multimedia And Internet, Amit Narielwala Aug 1999

Teaching Operating System Concepts Using Multimedia And Internet, Amit Narielwala

Theses

The prime objective of the thesis is to research and demonstrate the benefits and advantages of using Internet and multimedia tools for an interactive educational leaning experience. As we speak Internet is developing as a mainstream communication medium via personal computer as a tool at a breathtaking speed. The information technology field is a prime reason behind such phenomenon as it continues to mature and expand. In what is described as the "information age", the students of information technology need to master and devour new complex technological concepts and ideas at faster rate than ever before. The traditional approach using …


Some Notions Of Complex Adaptive Systems And Their Relationship To Our World, Jens G. Pohl Aug 1999

Some Notions Of Complex Adaptive Systems And Their Relationship To Our World, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

This paper assumes that the world we live in consists of many interwoven complex adaptive systems. In the literature such systems are characterized as comprising many moving parts and processes that interact significantly in a mostly non-linear manner. It is argued that the forces that act on such complex systems are not additive, and that their impact occurs along non-linear interactions within the system. In particular, many of these systems are adaptive in that they change their behavior (through their interactions) over time, so that if they are subjected to a similar force or event a second time they …


Re-Engineering A Software Development Organization As A Complex Adaptive System, Steven J. Gollery, Jens G. Pohl Aug 1999

Re-Engineering A Software Development Organization As A Complex Adaptive System, Steven J. Gollery, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

This paper proposes that it is possible and desirable to restructure a software development organization as a complex adaptive system. Such a structure would increase the possibility that the organization would be able to survive and prosper in a rapidly-changing market place by shortening response time, increasing flexibility in the face of new and unexpected circumstances, and allowing the organization to learn quickly from its experiences.

The paper shows how a common information repository can be used to provide decision support to developers and managers, and discusses the relationship between decision support systems and complex adaptive systems.


An Agent-Based Netcentric Framework For Multidisciplinary Problem Problem Solving Environments (Mpse), S. Markus, Elias N. Houstis, A. C. Catlin, John R. Rice, P. Tsompanopoulou, D. Gottfried, Ke Su Aug 1999

An Agent-Based Netcentric Framework For Multidisciplinary Problem Problem Solving Environments (Mpse), S. Markus, Elias N. Houstis, A. C. Catlin, John R. Rice, P. Tsompanopoulou, D. Gottfried, Ke Su

Department of Computer Science Technical Reports

No abstract provided.


First 20 Precision Among World Wide Web Search Services (Search Engines), H. Vernon Leighton, Jaideep Srivastava Jul 1999

First 20 Precision Among World Wide Web Search Services (Search Engines), H. Vernon Leighton, Jaideep Srivastava

Library Faculty Works

Five search engines, Alta Vista, Excite, Hotbot, Infoseek, and Lycos, are compared for precision on the first twenty results returned for fifteen queries. All searching was done from January 31 to March 12, 1997. Steps have been taken to ensure that bias has not unduly influence the evaluation. Friedmann's randomized block design is used to perform multiple comparisons for significance. Analysis shows that Alta Vista, Excite and Infoseek are the top three services, with their relative rank changing depending on how one interpreted the concept of "relevant."

Citation:

Leighton, H. Vernon and Jaideep Srivastava. "First 20 Precision among World Wide …


Combining Cross-Validation And Confidence To Measure Fitness, Tony R. Martinez, D. Randall Wilson Jul 1999

Combining Cross-Validation And Confidence To Measure Fitness, Tony R. Martinez, D. Randall Wilson

Faculty Publications

Neural network and machine learning algorithms often have parameters that must be tuned for good performance on a particular task. Leave-one-out cross-validation (LCV) accuracy is often used to measure the fitness of a set of parameter values. However, small changes in parameters often have no effect on LCV accuracy. Many learning algorithms can measure the confidence of a classification decision, but often confidence alone is an inappropriate measure of fitness. This paper proposes a combined measure of Cross- Validation and Confidence (CVC) for obtaining a continuous measure of fitness for sets of parameters in learning algorithms. This paper also proposes …


Cross Validation And Mlp Architecture Selection, Timothy L. Andersen, Tony R. Martinez Jul 1999

Cross Validation And Mlp Architecture Selection, Timothy L. Andersen, Tony R. Martinez

Faculty Publications

The performance of cross validation (CV) based MLP architecture selection is examined using 14 real world problem domains. When testing many different network architectures the results show that CV is only slightly more likely than random to select the optimal network architecture, and that the strategy of using the simplest available network architecture performs better than CV in this case. Experimental evidence suggests several reasons for the poor performance of CV. In addition, three general strategies which lead to significant increase in the performance of CV are proposed. While this paper focuses on using CV to select the optimal MLP …


Neural Networks And Structured Knowledge: Knowledge Representation And Reasoning, Franz J. Kurfess Jul 1999

Neural Networks And Structured Knowledge: Knowledge Representation And Reasoning, Franz J. Kurfess

Computer Science and Software Engineering

This collection of articles is the first of two parts of a special issue on "Neural Networks and Structured Knowledge." The contributions to the first part shed some light on the issues of knowledge representation and reasoning with neural networks. Their scope ranges from formal models for mapping discrete structures like graphs or logical formulae onto different types of neural networks, to the construction of practical systems for various types of reasoning. In the second part to follow, the emphasis will be on the extraction of knowledge from neural networks, and on applications of neural networks and structured knowledge to …


A Family Of Hierarchical Encoding Techniques For Image And Video Communications, Samah A. Senbel Jul 1999

A Family Of Hierarchical Encoding Techniques For Image And Video Communications, Samah A. Senbel

Computer Science Theses & Dissertations

As the demand for image and video transmission and interactive multimedia applications continues to grow, scalable image and video compression that has robust behavior over unreliable channels are of increasing interest. These desktop applications require scalability as a main feature due to its heterogeneous nature, since participants in an interactive multimedia application have different needs and processing power. Also, the encoding and decoding algorithm complexity must be low due to the practical considerations of low-cost low-power receiver terminals. This requires image and video encoding techniques that jointly considers compression, scalability, robustness, and simplicity.

In this dissertation, we present a family …


Newton Parameter Update Algorithm For Recurrent Neural Networks Applied To Adaptive System Identification And Control, Donald Allen Gates Jul 1999

Newton Parameter Update Algorithm For Recurrent Neural Networks Applied To Adaptive System Identification And Control, Donald Allen Gates

Electrical & Computer Engineering Theses & Dissertations

This paper shows that the combination of a second-order neural network parameter update algorithm and internal network feedback can be effectively used for adaptive, nonlinear, dynamical system identification and control. Adaptive neural identification and control algorithms are typically utilized for real-time applications where the rate of adaptation is often critical. A fast, adaptive network parameter update algorithm is presented.

Simulation results show that this algorithm is capable of quickly identifying and adapting to changes in system parameters, making it feasible to use for real-time control and fault accommodation applications.


A Comparison Of Eclectic Learning And Stagger, J. Cory Barker, Jargalsaihan Batsaihan Jul 1999

A Comparison Of Eclectic Learning And Stagger, J. Cory Barker, Jargalsaihan Batsaihan

Faculty Publications

This project compares two machine-learning methods, Stagger and Eclectic on their classification correctness. Both systems were tested with real-world data sets previously used and tested in other machine learning and statistical literature. The Eclectic System performed better than Stagger on every data set.


Zero-Parity Stabbing Information, Joseph O'Rourke, Irena Pashchenko Jun 1999

Zero-Parity Stabbing Information, Joseph O'Rourke, Irena Pashchenko

Computer Science: Faculty Publications

Everett et al. [EHN96, EHN97] introduced several varieties of stabbing information for the lines determined by pairs of vertices of a simple polygon P, and established their relationships to vertex visibility and other combinatorial data. In the same spirit, we define the “zero-parity (ZP) stabbing information” to be a natural weakening of their “weak stabbing information,” retaining only the distinction among {zero, odd, even > 0} in the number of polygon edges stabbed. Whereas the weak stabbing information’s relation to visibility remains an open problem, we completely settle the analogous questions for zero parity information, with three results: (1) ZP information …


Analysis Of N-Tier Architecture Applied To Distributed-Database Systems, Alexandre G. Valente Jun 1999

Analysis Of N-Tier Architecture Applied To Distributed-Database Systems, Alexandre G. Valente

Theses and Dissertations

N-tier architecture has been more commonly used as a methodology for developing large database applications. This work evaluates the use of this architecture instead of the classical Client/Server architecture in developing corporate applications based on distributed databases. The comparison between architectures is performed using applications that execute transactions similar to those defined in the Transaction Process Council Type C benchmark (TPC-C). The environment used for development and testing was the AFIT Bimodal Cluster (ABC); a heterogeneous cluster of PCs, running Microsoft Windows NT 4.0 OS. The comparative experimental analysis demonstrated that the N-tier architecture allows more efficient bandwidth utilization between …


A Two Dimensional Crystalline Atomic Unit Modular Self-Reconfigurable Robot, Marsette Arthur Vona Iii Jun 1999

A Two Dimensional Crystalline Atomic Unit Modular Self-Reconfigurable Robot, Marsette Arthur Vona Iii

Dartmouth College Undergraduate Theses

Self-reconfigurable robots are designed so that they can change their external shape without human intervention. One general way to achieve such functionality is to build a robot composed of multiple, identical unit modules. If the modules are designed so that they can be assembled into rigid structures, and so that individual units within such structures can be relocated within and about the structure, then self-reconfiguration is possible. We propose the Crystalline Atomic unit modular self-reconfigurable robot, where each unit is called an Atom. In two dimensions, an Atom is square. Connectors at the faces of each Atom support structure formation …


An Application Of Word Sense Disambiguation To Information Retrieval, Jason M. Whaley Jun 1999

An Application Of Word Sense Disambiguation To Information Retrieval, Jason M. Whaley

Dartmouth College Undergraduate Theses

The problems of word sense disambiguation and document indexing for information retrieval have been extensively studied. It has been observed that indexing using disambiguated meanings, rather than word stems, should improve information retrieval results. We present a new corpus-based algorithm for performing word sense disambiguation. The algorithm does not need to train on many senses of each word; it uses instead the probability that certain concepts will occur together. That algorithm is then used to index several corpa of documents. Our indexing algorithm does not generally outperform the traditional stem-based tf.idf model.


A Multilevel Secure Workflow Management System, Myong H. Kang, Judith N. Froscher, Amit P. Sheth, Krzysztof J. Kochut, John A. Miller Jun 1999

A Multilevel Secure Workflow Management System, Myong H. Kang, Judith N. Froscher, Amit P. Sheth, Krzysztof J. Kochut, John A. Miller

Kno.e.sis Publications

The Department of Defense (DoD) needs multilevel secure (MLS) workflow management systems to enable globally distributed users and applications to cooperate across classification levels to achieve mission critical goals. An MLS workflow management system that allows a user to program multilevel mission logic, to securely coordinate widely distributed tasks, and to monitor the progress of the workflow across classification levels is required. In this paper, we present a roadmap for implementing MLS workflows and focus on a workflow builder that is a graphical design tool for specifying such workflows.


Parallel Dassf Discrete-Event Simulation Without Shared Memory, James D. Chalfant Jun 1999

Parallel Dassf Discrete-Event Simulation Without Shared Memory, James D. Chalfant

Dartmouth College Undergraduate Theses

The Dartmouth implementation of the Scalable Simulation Framework (DaSSF) is a discrete-event simulator used primarily in the simulation of networks. It achieves high performance through parallel processing. DaSSF 1.22 requires shared memory between all processors in order to operate. This limits the number of processors available and the hardware platforms that can exploit parallelism. We are interested in extending parallel DaSSF operation to architectures without shared memory. We explore the requirements of this by implementing parallel DaSSF using MPI as the sole form of interaction between processors. The approaches used to achieve this can be abstracted and applied to the …


Two Algorithms For Performing Multidimensional, Multiprocessor, Out-Of-Core Ffts, Lauren M. Baptist Jun 1999

Two Algorithms For Performing Multidimensional, Multiprocessor, Out-Of-Core Ffts, Lauren M. Baptist

Dartmouth College Undergraduate Theses

We show two algorithms for computing multidimensional Fast Fourier Transforms (FFTs) on a multiprocessor system with distributed memory when problem sizes are so large that the data do not fit in the memory of the entire system. Instead, data reside on a parallel disk system and are brought into memory in sections. We use the Parallel Disk Model for implementation and analysis. The first method is a straightforward out-of-core variant of a well-known method for in-core, multidimensional FFTs. It performs 1-dimensional FFT computations on each dimension in turn. This method is easy to generalize to any number of dimensions, and …


Investigating Measures For Pairwise Document Similarity, Jeffrey D. Isaacs Jun 1999

Investigating Measures For Pairwise Document Similarity, Jeffrey D. Isaacs

Dartmouth College Undergraduate Theses

The need for a more effective similarity measure is growing as a result of the astonishing amount of information being placed online. Most existing similarity measures are defined by empirically derived formulas and cannot easily be extended to new applications. We present a pairwise document similarity measure based on Information Theory, and present corpus dependent and independent applications of this measure. When ranked with existing similarity measures over TREC FBIS data, our corpus dependent information theoretic similarity measure ranked first.


Considerations For An Effective Telecommunications-Use Policy, Michael E. Whitman, Anthony M. Townsend, Robert J. Aalberts Jun 1999

Considerations For An Effective Telecommunications-Use Policy, Michael E. Whitman, Anthony M. Townsend, Robert J. Aalberts

Faculty Articles

Recent changes in federal telecommunications legislation have underscored the importance of an up-to-date and effective telecommunications-use policy in business organizations. With the proliferation of the Internet, intranets, and email as commonplace business tools, the potential for misuse and subsequent liability has become an increasing concern. Even though the recent Supreme Court decision struck down the obscenity provisions of the Communications Decency Act (CDA), it left intact legislation that effectively mandates development of a sound telecommunications-use policy. In addition to potential liability for systems misuse, organizations have also had to address issues of individual employee privacy within the new systems.

This …


Fast Out-Of-Core Sorting On Parallel Disk Systems, Matthew D. Pearson Jun 1999

Fast Out-Of-Core Sorting On Parallel Disk Systems, Matthew D. Pearson

Dartmouth College Undergraduate Theses

This paper discusses our implementation of Rajasekaran's (l,m)-mergesort algorithm (LMM) for sorting on parallel disks. LMM is asymptotically optimal for large problems and has the additional advantage of a low constant in its I/O complexity. Our implementation is written in C using the ViC* I/O API for parallel disk systems. We compare the performance of LMM to that of the C library function qsort on a DEC Alpha server. qsort makes a good benchmark because it is fast and performs comparatively well under demand paging. Since qsort fails when the swap disk fills up, we can only compare these algorithms …


Multiscale Image Registration Using Scale Trace Correlation, Bruce B. Hansen, Bryan S. Morse Jun 1999

Multiscale Image Registration Using Scale Trace Correlation, Bruce B. Hansen, Bryan S. Morse

Faculty Publications

This paper presents a method for registering images at different magnifications (scales) by treating the problem not only as one of scaling the image coordinates but also as one inherently involving multiresolution information. While some existing methods for multiresolution registration do consider the way the resolution (scale) affects the image, they often consider the image one scale at a time, using geometric properties within that scale. Others use multiscale information, usually to produce more robust results, but only to register same-magnification images (e.g., stereo). A scale trace is the set of values that a single pixel takes on as magnification …


Sketch-Based Image Queries In Topographic Databases, James Carswell Jun 1999

Sketch-Based Image Queries In Topographic Databases, James Carswell

Articles

In this paper we present the development of a system prototype for sketch-based queries for the content-based retrieval of digital images from topographic databases. We discuss our overall strategy and associated algorithmic and implementation aspects, and present associated database design issues. The query tools devised in this research are employing user-provided sketches of the shape and spatial configuration of the object(s) which should appear in the images to be retrieved. Our matching tool is inspired by least-squares matching (lsm), and represents an extension of lsm to function with a variety of raster representations. Our strategy makes use of a hierarchical …


Camera Break Detection By Partitioning Of 2d Spatio-Temporal Images In Mpeg Domain, Chong-Wah Ngo Jun 1999

Camera Break Detection By Partitioning Of 2d Spatio-Temporal Images In Mpeg Domain, Chong-Wah Ngo

Research Collection School Of Computing and Information Systems

In this paper, we propose a new approach to detect camera cuts and wipes. The approach projects a video into two images representing the spatio-temporal continuity of a video life. Visually, these images are composed by regions of different patterns, each region represents the temporal location of a shot. The shape of a region boundary inherently classifies cut and wipe, and most importantly, marks the start and end of a wipe sequence. We hence formulate algorithms to locate the color and texture discontinuities occurring at the boundaries of image regions.


Methodology For Integrating The Scenario Databases Of Simulation Systems, Emilia M. Colonese Jun 1999

Methodology For Integrating The Scenario Databases Of Simulation Systems, Emilia M. Colonese

Theses and Dissertations

The use of many different simulation systems by the United States Department of Defense has resulted in many different scenario data representations contained in heterogeneous databases. These heterogeneous databases all represent the same data concept, but have different semantics due to intrinsic variations among the data models. In this research, I describe a unified scenario database to allow interoperability and reuse of the scenario data components while avoiding the problems of data redundancy. Using the object oriented approach, the data and schema of the scenario databases, represented in an object oriented model, are integrated into a global database also represented …


Cobol Reengineering Using The Parameter Based Object Identification (Pboi) Methodology, Sonia De Jesus Rodrigues Jun 1999

Cobol Reengineering Using The Parameter Based Object Identification (Pboi) Methodology, Sonia De Jesus Rodrigues

Theses and Dissertations

This research focuses on how to reengineer Cobol legacy systems into object oriented systems using Sward's Parameter Based Object Identification (PBOI) methodology. The method is based on relating categories of imperative subprograms to classes written in object oriented language based on how parameters are handled and shared among them. The input language of PBOI is a canonical form called the generic imperative model (GIM), which is an abstract syntax tree (AST) representation of a simple imperative programming language. The output is another AST, the generic object model (GOM), a generic object oriented language. Conventional languages must be translated into the …


Parallel Digital Signal Processing On A Network Of Personal Computers Case Study: Space-Time Adaptive Processing, Fernando Silva Jun 1999

Parallel Digital Signal Processing On A Network Of Personal Computers Case Study: Space-Time Adaptive Processing, Fernando Silva

Theses and Dissertations

Network based parallel computing using personal computers is currently a popular choice for concurrent scientific computing. This work evaluates the capabilities and the performance of the AFIT Bimodal Cluster (ABC); a heterogeneous cluster of PCs connected by switched fast Ethernet and using MPICH 1.1 for interprocess communication for parallel digital signal processing using Space Time Adaptive Processing (STAP) as the case study. The MITRE RT_STAP Benchmark version 1.1 is ported and executed on the ABC, as well as on a cluster of six Sun SPARC workstations connected by a Myrinet network (the AFIT NOW), and on a IBM SP for …