Digital Commons Network^™

Extending The Power And Capacity Of Constraint Satisfaction Networks, Tony R. Martinez, Xinchuan Zeng

Faculty Publications

This work focuses on improving the Hopfield network for solving optimization problems. Although much work has been done in this area, the performance of the Hopfield network is still not satisfactory in terms of valid convergence and quality of solutions. We address this issue in this work by combing a new activation function (EBA) and a new relaxation procedure (CR) in order to improve the performance of the Hopfield network. Each of EBA and CR has been individually demonstrated capable of substantially improving the performance. The combined approach has been evaluated through 20,000 simulations based on 200 randomly generated city …

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

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 …

The Little Neuron That Could, Timothy L. Andersen, Tony R. Martinez

Faculty Publications

SLPs (single layer perceptrons) oflen exhibit reasonable generalization performance on many problems of interest. However, due to the well known limitations of SLPs very little effort has been made to improve their performance. This paper proposes a method for improving the performance of SLPs called "wagging" (weight averaging). This method involves training several different SLPs on the same training data, and then averaging their weights to obtain a single SLP. The performance of the wagged SLP is compared with other more complex learning algorithms (bp, c4.5, ibl, MML, etc) on 15 data sets from real world problem domains. Surprisingly, the …

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 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.

Dynamic And Interactive 3d Simulation Over The World Wide Web, Rajesh Vennam

Electrical & Computer Engineering Theses & Dissertations

The thesis presents the development of a new and novel three-dimensional simulation tool over the WWW using Virtual Reality Modeling Language (VRML). VRML is a 3D analog to HTML and serves as a simple, multiplatform language for publishing 3D Web pages. In general, most people use VRML for developing three-dimensional models or worlds that provide little or no interaction for the users. This tool combines interaction and dynamic object creation. A thorough study of VRML is done to explore the features of VRML that could be combined to develop methodologies for creation of dynamic and interactive 3D objects over the …

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.

Model Predictive Satisficing Fuzzy Logic Control, Richard L. Frost, Michael A. Goodrich, Wynn C. Stirling

Faculty Publications

Model-predictive control, which is an alternative to conventional optimal control, provides controller solutions to many constrained and nonlinear control problems. However, even when a good model is available, it may be necessary for an expert to specify the relationship between local model predictions and global system performance. We present a satisficing fuzzy logic controller that is based on a receding control horizon, but which employs a fuzzy description of system consequences via model predictions. This controller considers the gains and losses associated with each control action, is compatible with robust design objectives, and permits flexible defuzzifier design. We demonstrate the …

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 …

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 …

Toboggan-Based Intelligent Scissors With A Four-Parameter Edge Model, William A. Barrett, Eric N. Mortensen

Faculty Publications

Intelligent Scissors is an interactive image segmentation tool that allows a user to select piece-wise globally optimal contour segments that correspond to a desired object boundary. We present a new and faster method of computing the optimal path by over-segmenting the image using tobogganing and then imposing a weighted planar graph on top of the resulting region boundaries. The resulting region-based graph is many times smaller than the previous pixel-based graph, thus providing faster graph searches and immediate user interaction. Further, tobogganing provides an new systematic and predictable framework for computing edge model parameters, allowing subpixel localization as well as …

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.

The Effectiveness Of Expert Support Technology For Decision Making: Individuals Versus Small Groups, Fiona Fui-Hoon Nah, Jiye Mao, Izak Benbasat

Research Collection School Of Computing and Information Systems

Expert support systems (ESSs) are increasingly used in organizations to support individuals and groups in decision making. Although ESSs have been shown to enhance the decision-making capabilities of individuals, their benefits in supporting group decision making are less clear. To the best of our knowledge, no empirical research has evaluated the effectiveness of the technology in the group setting or compared its usefulness for supporting individual versus group decision making. The results of this research show that ESSs benefit decision making of both individuals and groups and novices are able to gain more from ESSs than experts. The findings also …

Detection Of Gradual Transitions Through Temporal Slice Analysis, Chong-Wah Ngo, T. C. Pong, R. T. Chin

Research Collection School Of Computing and Information Systems

In this paper, we present approaches for detecting camera cuts, wipes and dissolves based on the analysis of spatio-temporal slices obtained from videos. These slices are composed of spatial ly and temporal ly coherent regions which can be perceived as shots. In the proposed methods, camera breaks are located by performing color-texture segmentation and statistical analysis on these video slices. In addition to detecting camera breaks, our methods can classify the detected breaks as camera cuts, wipes and dissolves in an efficient manner

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 …

Modeling Controlled Vocabularies Using Oodbs And Multilevel Area Diagrams, Li-Min Liu

Dissertations

A Controlled Vocabulary (CV) is a software system of domain knowledge that consolidates and unifies the terminology of a large application domain. With a common, centralized CV, costly and time-consuming translations can be eliminated between pairs of organizations and pairs of software systems. Unfortunately, the more knowledge we put into a CV, the harder it is to understand and maintain it. In this dissertation, a comprehensive theoretical methodology for modeling CVs using Object-Oriented Database (OODB) technology is presented. We present two methods for representing a semantic network CV as an equivalent OODB, which we call an Object-Oriented Vocabulary Repository (OOVR). …

Recasting Cohn's Many Sorted Logic Into A Constrained Logic, Christopher Brendan Koelbl

Theses

The use of a many sorted logic for theorem proving carries many advantages over a traditional unsorted logic. By placing restrictions on the search space, a many sorted logic can significantly reduce the amount steps in the resolution process. However, as a logic becomes more efficient, it increases in complexity.

One of these efficient log ics is Cohn's Many Sorted Logic, LLAMA. It uses complex data structures such as the sort lattice and sort arrays to maintain information about the sorts. Recasting LLAMA into Bürckert's constrained logic will keep the functionality of LLAMA while using a format that reduces the …

Tracking The Trochoid On Safari, Andrew Simoson

ACMS Conference Proceedings 1999

While on sabbatical in Dar es Salaam in 1997–98, I was tasked to be the department’s seminar director and discovered that a dearth of speakers roam about in east Africa; so I opted to set up a lecture tour for myself to include Zambia, Zimbabwe, and Botswana as well as Tanzania—and spoke about the envelope of curves generated by a series of line segments obtained when two runners attached by an ideal bungee cord (the line segments) proceed about a circular track. Herein we describe life in east Africa and show that those envelopes are trochoids.

Notepals: Lightweight Note Sharing By The Group, For The Group, Richard C. Davis, James A. Landay, Victor Chen, Jonathan Huang, Rebecca B. Lee, Francis Li, James Lin, Charles B. Morrey, Morgan N. Price, Bill N. Schilit

Research Collection School Of Computing and Information Systems

NotePals is a lightweight note sharing system that gives group members easy access to each others experiences through their personal notes. The system allows notes taken by group members in any context to be uploaded to a shared repository. Group members view these notes with browsers that allow them to retrieve all notes taken in a given context or to access notes from other related notes or documents. This is possible because NotePals records the context in which each note is created (e.g., its author, subject, and creation time). The system is lightweight because it fits easily into group members …

The Dynamics Of Cyberspace: Examining And Modelling Online Social Structure, Brian S. Butler '89

Doctoral Dissertations

It has been proposed that online social structures represent new forms of organizing which are fundamentally different from traditional social structures. However, while there is a growing body of empirical research that considers behavioral aspects of online activity, research on online social structure structural remains largely anecdotal. This work consists of three papers that combine previous studies of traditional social structures, empirical analysis of longitudinal data from a sample of Internet listservs, and computational modeling to examine the dynamics of social structure development in networked environments.

The first paper (Title: When is a Group not a Group: An Empirical Examination …

A Systolic Algorithm To Process Compressed Binary Images, Fikret Erçal, Mark Allen, Hao Feng

Computer Science Faculty Research & Creative Works

A new systolic algorithm which computes image differences in run-length encoded (RLE) format is described. The binary image difference operation is commonly used in many image processing applications including automated inspection systems, character recognition, fingerprint analysis, and motion detection. The efficiency of these operations can be improved significantly with the availability of a fast systolic system that computes the image difference as described in this paper It is shown that for images with a high similarity measure, the time complexity of the systolic algorithm is small and in some cases constant with respect to the image size. The time for …

Information Modeling And Method Engineering: A Psychological Perspective, Keng Siau

Research Collection School Of Computing and Information Systems

Information modeling is the cornerstone of information systems analysis and design. Information models, the products of information modeling, not only provide the abstractions required to facilitate communication between the analysts and end users, but they also provide a formal basis for developing tools and techniques used in information systems development. The process of designing, constructing, and adapting information modeling methods for information systems development is known as method engineering. Despite the pivotal role of modeling methods in successful information systems development, most modeling methods are designed based on common sense and intuition of the method designers with little or no …

Pi-Web Join In A Web Warehouse, Sourav S. Bhowmick, Sanjay Kumar Madria, Wee-Keong Ng, Ee Peng Lim

Research Collection School Of Computing and Information Systems

With the enormous amount of data stored in the World Wide Web, it is increasingly important to design and develop powerful web warehousing tools. The key objective of our web warehousing project, called WHOWEDA (Warehouse of Web Data), is to design and implement a web warehouse that materializes and manages useful information from the Web. In this paper, we introduce the concept of Pi-web join in the context of WHOWEDA. Pi-web join operator is a web information manipulation operator to combine relevant web information residing in two web tables. Informally, it is the combination of web join and web project …

Resource Scheduling In A High-Performance Multimedia Server, Hwee Hwa Pang, Bobby Jose, M. S. Krishnan

Research Collection School Of Computing and Information Systems

Supporting continuous media data-such as video and audio-imposes stringent demands on the retrieval performance of a multimedia server. In this paper, we propose and evaluate a set of data placement and retrieval algorithms to exploit the full capacity of the disks in a multimedia server. The data placement algorithm declusters every object over all of the disks in the server-using a time-based declustering unit-with the aim of balancing the disk load. As for runtime retrieval, the quintessence of the algorithm is to give each disk advance notification of the blocks that have to be fetched in the impending time periods, …

The Window Distribution Of Idealized Tcp Congestion Avoidance With Variable Packet Loss, Archan Misra, Teunis J. Ott

Research Collection School Of Computing and Information Systems

This paper analyzes the stationary behavior of the TCP congestion window performing ideal congestion avoidance when the packet loss probability is not constant, but varies as a function of the window size. By neglecting the detailed window behavior during fast recovery, we are able to derive a Markov process that is then approximated by a continuous-time, continuous state space process. The stationary distribution of this process is analyzed and derived numerically and then extrapolated to obtain the stationary distribution of the TCP window. This numerical analysis enables us to predict the behavior of the TCP congestion window when interacting with …

Research And Implementation Of Integrated Concurrent Software Development Environment Based On Object-Oriented Petri Nets, Jinzhong Niu

Publications and Research

While network technologies and environments get more and more popular, the demand for concurrent systems becomes stronger and stronger. But the characteristics of concurrency make it difficult to develop them.

This dissertation combines Object-Oriented technology and Petri Nets theory, and put forth OOPN (OO Petri Nets) model to describe concurrent systems. Based on the research of conventional development methods of concurrent software, this article advances a new one, which integrates specification, validation and auto-generating codes. Accordingly, an integrated development environment for concurrent software, i.e., OOPN-IDE, comes into being, which mainly includes the following four tools: the concurrent system modeling tool …

Continuation-Passing Style Versus Direct Style: Choosing An Intermediate Representation For Higher-Order Applicative Languages, Paul Andrew Seale

Dissertations and Theses

This study analyzes the use of a continuation-passing style (CPS) intermediate representation versus a direct style intermediate representation in the compilation of a higher-order applicative language. The translator used accepts a program written in an ML-like language as input, and outputs a C program acceptable to a standard C compiler. The effects of the translator's simplification and higher-order function removal transformations on the intermediate language are the primary focus of the analysis. The machine code programs generated from both representations are also analyzed.

Initially, the programs under the direct style representation performed better than those that underwent the CPS transformation. …

A Comparative Study Of Sequence Analysis Tools In Computational Biology, Wei-Jen Chuang

Theses

A biomolecular object, such as a deoxyribonucleic acid (DNA), a ribonucleic acid (RNA) or a protein molecule, is made up of a long chain of subunits. A protein is represented as a sequence made from 20 different amino acids, each represented as a letter. There are a vast number of ways in which similar structural domains can be generated in proteins by different amino acid sequences. By contrast, the structure of DNA, made up of only four different nucleotide building blocks that occur in two pairs, is relatively simple, regular, and predictable.

Biomolecular sequence alignment/string search is the most important …

Java’S Insecure Parallelism, Per Brinch Hansen

College of Engineering and Computer Science - Former Departments, Centers, Institutes and Projects

The author examines the synchronization features of Java and finds that they are insecure variants of his earliest ideas in parallel programming published in 1972-73. The claim that Java supports monitors is shown to be false. The author concludes that Java ignores the last twenty-five years of research in parallel programming languages.