Digital Commons Network^™

On Correspondence, Line Tokens And Missing Tokens, Chia-Hoang Lee, Anupam Joshi

Department of Computer Science Technical Reports

No abstract provided.

The Visual Diagnosis On The Numerical Calculation Of Pde Problems, Yukio Umetani

Department of Computer Science Technical Reports

No abstract provided.

Improving Gl Surface Joins By Using A Composite Patch, Jörg Peters

Department of Computer Science Technical Reports

No abstract provided.

Efficient Techniques For Simulating Service Disciplines, Janche Sang, Ke-Hsiung Chung, Vernon J. Rego

Department of Computer Science Technical Reports

No abstract provided.

Experiments With Program Unification On The Cray Y-Mp, Ling-Yu Chuang, Vernon J. Rego, Aditya P. Mathur

Department of Computer Science Technical Reports

No abstract provided.

A New Family Of Preconditioners For Domain Decomposition, Mo Mu

Department of Computer Science Technical Reports

No abstract provided.

A Performance Comparison Of Simulation Calendar Algorithms: An Empirical Approach, Kehsiung Chung, Janche Sang, Vernon J. Rego

Department of Computer Science Technical Reports

No abstract provided.

A Generic Virus Scanner In C++, Sandeep Kumar, Eugene H. Spafford

Department of Computer Science Technical Reports

No abstract provided.

Backpropagation Learns Marr's Operator, Anupam Joshi, Chia-Hoang Lee

Department of Computer Science Technical Reports

No abstract provided.

The Management Of Replicated Data, Hsueh-Chi Shih, C. Y. Ho, S. Alptekin

Computer Science Technical Reports

Data replication, which has the benefits of improving system availability and read performance, proved to be indispensable to many database applications. In a replicated database, the one-copy serializability of transaction executions can be ensured by employing a replica control mechanism on top of the traditional concurrency control mechanism. This work contains two replica control algorithms and a read-only transaction processing algorithm. Both replica control algorithms handle multiple site, communication and partitioning failures. The replica control algorithms achieve read operation efficiency by always translating a logical read operation into one local physical read operation and by taking advantage of the locality …

Formal Derivation Of An Error-Detecting Distributed Data Scheduler Using Changeling, Hanan Lutffiya, Bruce M. Mcmillin, Alan Su

Computer Science Technical Reports

Distributed database applications are a wide use of distributed systems. One of the major advantages of distributed database systems is the potential for achieving high availability in the presence of faults. Faults must be handled so that the system still operates or operates in a degraded mode. This paper focuses on being able to detect component errors which can lead to system failures in the scheduling part of the lock manager portion of the distributed database system by using embedded executable assertions. Changeling provides a systematic approach, based on the mathematical model of program verification, to deriving executable assertions that …

An Analysis Of Product Metrics In Terms Of Qualitative And Formal Metric Properties, Tuliz Dengi, George Zobrist

Computer Science Technical Reports

In recent years, the increased concern for developing reliable, cost-efficient software systems has been accompanied by a higher need to analyze and measure software complexity. Numerous metrics have been proposed to measure software complexity and functionality. Yet, testing the validity of these metrics has been a difficult and long process. As an initial test of metric validity, some researchers have suggested the use of formal metric properties so that metrics without a sound theoretical base are rejected right away. This approach has the additional advantage of allowing a reasonable and fair comparison of software metrics.

In this study, a discussion …

An Object-Oriented Approach To Data Exchange Applications: Development Of A Class Library For The Spatial Data Transfer Standard, Phyllis Altheida, John Prater

Computer Science Technical Reports

The object-orienced paradigm embodies a set of concepts that differentiates it from process-oriented and data-oriented methods. Among che commonly included principles are object, class, encapsulation, inheritance and polymorphism. The synergism of the concepts creates a powerful and new perspective that can be applied to all phases of systems development. Application developers need to try out the object-oriented languages, methodologies and development tools to help define its niche. The problem domain of data transfer standards is used to test the applicability of object-oriented techniques. Data transfer standards have three levels of abstraction: conceptual, logical, and format. The Spatial Data Transfer Standard …

An Animation System For Shift Reduce Parsers, M. S. Mandl, T. J. Sager, D. C. St. Clair

Computer Science Technical Reports

This paper presents the design and implementation of the Parse Display Utility (POU) system. This system introduces a mechanism to augment traditional methods of exploring parsing theory by providing a PRESENTATION scheme which allows a user to view the operation of a shift-reduce parser.

The overall operation of the tool revolves around an LALR (LookAhead LR) parser/parser generator and is managed by a Graphical User-Interface (GUI) developed using Borland's Turbo Vision product. The GUI allows access to a facility which draws derivation trees in Turbo Pascal graphics. This parse tree facility utilizes an algorithm which can easily be ported to …

Constructing Cl Surfaces Of Arbitrary Topology Using Biquadratic And Bicubic Splines, Jörg Peters

Department of Computer Science Technical Reports

No abstract provided.

On The Problem Of Correspondence In Range Data And Some Inelastic Uses For Elastic Nets, Anupam Joshi, Chia-Hoang Lee

Department of Computer Science Technical Reports

No abstract provided.

The Emergence Of Algebraic Curves And Surfaces In Geometric Design, Chandrajit L. Bajaj

Department of Computer Science Technical Reports

No abstract provided.

Effect Of The X² Test On Construction Of Id3 Decision Trees, Mayank Thakore, Daniel C. St. Clair

Computer Science Technical Reports

Inductive machine learning algorithms are knowledge-based learning algorithms which take training instances as input and produce knowledge as output. One popular induction algorithm is Quinlan's ID3 [1986]. This algorithm produces knowledge in the form of a decision tree. Each path in the tree can be interpreted as a rule with the leaves representing rule conclusions. Selected attributes which describe the training instances form the interior nodes of the tree.

The ID3 algorithm is extremely sensitive to noisy training data. In an effort to reduce the effects of noise on tree construction, Quinlan used the X² test to identify noisy …

Multiple-Length Division Revisited: A Tour Of The Minefield, Per Brinch Hansen

Electrical Engineering and Computer Science - Technical Reports

Long division of natural numbers plays a crucial role in Cobol arithmetic, cryptography, and primality testing. Only a handful of textbooks discuss the theory and practice of long division, and none of them do it satisfactorily. This tutorial attempts to fill this surprising gap in the literature on computer algorithms. We illustrate the subtleties of long division by examples, define the problem concisely, summarize the theory, and develop a complete Pascal algorithm using a consistent terminology.

Numerical Solution Of Laplace's Equation, Per Brinch Hansen

Electrical Engineering and Computer Science - Technical Reports

This tutorial discusses Laplace's equation for steady state heat flow in a two-dimensional region with fixed temperatures on the boundaries. The equilibrium temperatures are computed for a square grid using successive overrelaxation with parity ordering of the grid elements. The numerical method is illustrated by a Pascal algorithm. We assume that the reader is familiar with elementary calculus.

Parallel Cellular Automata: A Model Program For Computational Science, Per Brinch Hansen

Electrical Engineering and Computer Science - Technical Reports

We develop a model program for parallel execution of cellular automata on a multicomputer. The model program is then adapted for simulation of forest fires and numerical solution of Laplace's equation for stationary heat flow. The performance of the parallel program is analyzed and measured on a Computing Surface configured as a matrix of transputers with distributed memory.

Development Of An Environment For Software Reliability Model Selection, Salah A. Elewa

Theses and Dissertations

An environment was developed for solving the problem of selecting a proper software reliability model for a given set of software failures. The idea behind the environment developed in this dissertation was to liken a collected set of software failure data to a previous one that proved to fit well with a specified software reliability model. Software failures were assumed to have a two-Parameter exponential distribution with unequal type II censoring. A test criterion was derived for testing Ratio Criterion. The exact distribution of the test criterion was derived. An asymptotic approximation was also obtained and was found to be …

Award Fee In Software Acquisition, Mark T. Hunter

Theses and Dissertations

The focus of this research effort was to determine, in general terms, what contractual tools are available to influence contractor performance during the software development process and, specifically, whether or not award fee contracts are appropriate tools. First, a qualitative, in depth literature review was done. Next, personal interviews were conducted with Program Directors and Deputy Program Directors at Aeronautical Systems Center, Electronic Systems Center, and Space and Missiles Systems Center. Then, after the results were summarized, the data was analyzed and findings were made. Findings include: award fee was found to be the most flexible provision in the FAR …

Minimum Separation For Single-Layer Channel Routing, Ronald I. Greenberg, F. Miller Maley

Computer Science: Faculty Publications and Other Works

We present a linear-time algorithm for determining the minimum height of a single-layer routing channel. The algorithm handles single-sided connections and multiterminal nets. It yields a simple routability test for single-layer switchboxes, correcting an error in the literature.

The Development Of An Expert System For Hazardous Cargo Compatibility, Douglas A. Furst, Ronald E. Smith

Theses and Dissertations

This research demonstrates the application of expert system technology to automate the aircraft load selection process performed when transporting hazardous cargo. The resulting computer program is an expert system named HAZARD. This system incorporates the regulations governing hazardous cargo compatibility with the heuristics used by experts in loadplanning operations. The impetus to develop such a system is the January 1993 conversion of regulation guidelines for hazardous cargo classification and management in Air Force Regulation 71-4, to a universal international standard. The Cargo Operations Division of Headquarters Air Mobility Command at Scott AFB, was concerned that this change in procedures and …

Comparative Evaluation Of A Monocular Head Mounted Display Device Versus A Flat Screen Display Device In Presenting Aircraft Maintenance Technical Data, Jeffrey A. Friend, Randy S. Grinstead

Theses and Dissertations

As military developers provide increasingly complex weapon system, it becomes more difficult for maintenance technicians to perform their jobs. One aspect of the technicians' world is the need to access technical information in the performance of their duties. This study investigated two electronic display systems to evaluate which enhanced technician performance more. A Head Mounted Display (HMD) device and a portable hand-held flat-screen computer were evaluated in the performance of two flightline maintenance activities. Although both display systems were fully portable and self contained, only the HMD system allowed continuous access to technical information during task performance. In most cases, …

Comparison Of Four-Cursor Buttons Vs Joystick To Access Computerized Technical Information From An Integrated Maintenance Information System, Gerald E. Streff, Robert H. Gundel

Theses and Dissertations

The purpose of this thesis was to evaluate the use of four-cursor buttons versus a joystick device to present technical order information on a portable maintenance aid computer for aircraft technicians in a maintenance environment. Studies to date have verified the superiority of computer-presented technical orders when compared to current paper-based systems; this research investigated the effectiveness of these computer-based systems when technicians used a joystick or four-cursor button to display desired technical information. A comparison was made as to technician performance using a portable maintenance aid at the 4950th Test Wing, WPAFB OH. A total of thirty-two maintenance technicians …

Autonomous Face Segmentation, Kevin P. Gay

Theses and Dissertations

The purpose of this study was to implement an autonomous face segmentor as the front end to a face recognition system on a Sun SPARCStation2. Face recognition performance criteria, specifically, the capabilities to isolate and resize faces in an image to a consistent scale, were analyzed to determine current practical limitations. Face images were acquired using a S-VHS camcorder. Segmentation was accomplished using motion detection and predefined rules. Tests were run to determine the suitable of the autonomous segmentor as the front-end to a face recognition system. The segmentation system developed consistently located faces and rescaled those faces to a …

Robust Display Of Arbitrary Rational Parametric Surfaces, Chandrajit L. Bajaj, Andrew V. Royappa

Department of Computer Science Technical Reports

No abstract provided.

Design And Implementation Of The Raid V2 Distributed Database System, Bharat Bhargava, Karl Friesen, Abdelsalum Helal, Enrique Malfa, John Riedel

Department of Computer Science Technical Reports

No abstract provided.