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A Hypermedia Implementation For Reusable Software Component Representation, Gary G. Worrall Dec 1990

A Hypermedia Implementation For Reusable Software Component Representation, Gary G. Worrall

Theses and Dissertations

This study investigated software component representation methods. Hypermedia was chosen as the implementation method to represent a collection of reusable software components. The hypermedia implementation organizes knowledge about the component collection into a web of small information chunks called frames. The set of software components was represented using a hybrid classification scheme composed of enumerated and faceted parts. The enumerated part enables the user to progress along a path in a taxonomic tree, narrowing the scope of eligible components. Each leaf node in this tree denotes a class of components, members of which are distinguished by their time and space …

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Using Error Detection And Correction Coding For A Turbulent Atmospheric Optical Communications Link, Mark A. Cloutier Dec 1990

Using Error Detection And Correction Coding For A Turbulent Atmospheric Optical Communications Link, Mark A. Cloutier

Theses and Dissertations

Probability of bit error (Pb) performance for a turbulent, atmospheric, optical, communications link with convolutional error detection and correction coding was investigated. The codes investigated were all rate 1/2 codes with constraint lengths ranging from 3 to 7. It was assumed that the coded data stream was sufficiently interleaved so that the turbulent channel could be considered memoryless. A theoretical bound on Pb, given by Viterbi for a memoryless channel, was used to plot curves of Pb versus the signal intensity of last transmitter. These curves were plotted for three different levels of atmospheric turbulence and three …

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Determining Concurrency In Object-Oriented Design Of Real-Time Embedded Systems Using Ada, Kenneth D. Baum Dec 1990

Determining Concurrency In Object-Oriented Design Of Real-Time Embedded Systems Using Ada, Kenneth D. Baum

Theses and Dissertations

One of the characteristics of real-time systems is concurrency. Designers of real-time systems have traditionally determined system concurrency at implementation time using the facilities of a cyclic executive. With the advent of programming language constructs for specifying concurrency, determining concurrency at design time has become a possibility. Several design methods, all of which are extensions of either Structured Design or Jackson System Development, provide heuristics to help the designer make concurrency decisions. The object-oriented approach, however, has no corresponding heuristics to aid designers of real-time systems. The purpose of this thesis was to develop heuristics to help designers make concurrency …

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Access And Operator Methods For The Triton Nested Relational Database System, Tina M. Harvey Dec 1990

Access And Operator Methods For The Triton Nested Relational Database System, Tina M. Harvey

Theses and Dissertations

Unique database requirements in the realm of non-standard applications (such as computer-aided design (CAD), computer-aided software engineering(CASE), and office information systems (OIS) have driven the development of new data models and database systems based on these new models. In particular, the goal of these new database systems is to exploit the advantages of complex data models that are more efficient (in terms of time and space) than their relationship counterparts. This research effort describes the relational design and implementation of the Triton nested relational database system, a prototype system based on the nested relational data model. Triton is intended to …

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An Object-Oriented Military Simulation Baseline For Parallel Simulation Research, Robert J. Rizza Dec 1990

An Object-Oriented Military Simulation Baseline For Parallel Simulation Research, Robert J. Rizza

Theses and Dissertations

This thesis documents the design and implementation of a discrete event military simulation using a modular object-oriented design and the C programming language. The basis simulation is one of interacting objects. The objects move along a predetermined path until they encounter another object. Objects react to the encounter object according to the implemented algorithm. Object reaction options are fight, evade, or do nothing. In the code's current form it is generic enough to allow a user the flexibility of creating an infinite number of scenarios bounded in size by the hardware's memory capacity. The modularity of design will allow for …

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An Object Oriented Design And Implementation Of The Idef0 Essential Data Model Using Ada And An Ada Based Expert System, Terry L. Kitchen Dec 1990

An Object Oriented Design And Implementation Of The Idef0 Essential Data Model Using Ada And An Ada Based Expert System, Terry L. Kitchen

Theses and Dissertations

This thesis develops and implements an Ada based object oriented design (OOD) of the IDEF0 Essential Data Model called the Essential Subsystem, which includes an Ada based expert system for IDEF0 model syntax checking. IDEF0 is a graphic approach to system description development by SofTech, Inc. for the U.S. Air Force Program for Integrated Computer Aided Manufacturing (ICAM) and is a subset of the Structured Analysis (SA) language (30, 36). The IDEF0 Essential Data Model is an entity-relationship (E-R) model of the IDEF0 language and represents the fundamental (essential) information of an IDEF0 model. …

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A Remote Visual Interface Tool For Simulation Control And Display, William J. Derouchey Dec 1990

A Remote Visual Interface Tool For Simulation Control And Display, William J. Derouchey

Theses and Dissertations

This thesis discusses the design and development of the Visual Interactive Simulation Interface Tool (VISIT). VISIT was designed to provide the graphical representation and user interface for a simulation that is running on another processor utilizing internet communications. The system provides support for various input devices to control the simulation display and environment. Simulation objects are displayed using either a three-dimensional wireframe representation or a Gouraud shaded representation. Viewer interaction to the simulation is provided by a collection of commands that allow the viewer to initialize, start, stop, abort, and restart the simulations. The viewer also has the ability to …

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Real-Time Flight Simulation And The Head-Mounted Display - An Inexpensive Approach To Military Pilot Training, Philip A. Platt Dec 1990

Real-Time Flight Simulation And The Head-Mounted Display - An Inexpensive Approach To Military Pilot Training, Philip A. Platt

Theses and Dissertations

The integration of the low-cost head-mounted display (HMD), an inexpensive graphics workstation-based flight simulator, and a communications network was investigated to determine if the prototype of an inexpensive multi- aircraft Virtual Flight Simulator could be built. Previous research efforts have coupled HMD technology and flight simulation; however, the cost of these systems has been high. This thesis effort emphasized the use of joystick devices to emulate pilot control, the implementation of a fully enclosed virtual flight simulator, and the utilization of low-cost NTSC-based television technology to produce a prototype. The virtual flight simulator also contained a basic set of instruments …

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The Development Of A Graphical Notation For The Formal Specification Of Software, Gene A. Place Dec 1990

The Development Of A Graphical Notation For The Formal Specification Of Software, Gene A. Place

Theses and Dissertations

The program tranformations lifecycle model, proposed by Balzer in 1984, may hold the key to dramatic leap in software engineer productivity necessitated by the tremendous growth in the world's demand for software. This leap in productivity is made possible by the program transformation lifecycle's reliance on formal specifications rather than programs as the primary vehicle for the creation and maintenance of software systems. Because formal specifications are concerned only with system behaviors and not implementation details, formal specifications tend to present critical system characteristics much more concisely than programs. The major disadvantage of using formal specifications in a software development …

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An Evaluation Of An Ada Implementation Of The Rete Algorithm For Embedded Flight Processors, F. Jesse Fanning Dec 1990

An Evaluation Of An Ada Implementation Of The Rete Algorithm For Embedded Flight Processors, F. Jesse Fanning

Theses and Dissertations

The purpose of this thesis was to design and develop an expert system shell in Ada, and to evaluate the shell's execution and size performance to determine its suitability for real-time operation on the MIL-STD-1750A embedded flight processor. The expert system shell uses the CLIPS/Ada inference engine, a forward-chaining Ada implementation of Rete. The expert system shell design is presented along with an overview of the target environment--the MIL-STD-1750A VHSIC Avionic Modular Processor (VAMP) running under the Ada Avionics Real-Time Software (AARTS) Operating System. Theoretical and empirical complexity analyses of the inference engine are presented and discussed in view of …

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A Biologically-Inspired Neural Network Architecture For Image Processing, Laurence E. Lazofson Dec 1990

A Biologically-Inspired Neural Network Architecture For Image Processing, Laurence E. Lazofson

Theses and Dissertations

This thesis project included a literature survey of biological and artificial neural network research followed by development and testing of high- order and image recognition hierarchical neural network algorithms. Following training, performance testing of second-order and third-order networks yielded maximum accuracies comparable to those achieved by multilayer perceptron classifiers operating on test data sets. Several versions of an image classification algorithm were tested for learning performance using pixel data from forward-looking infrared (FLIR) images of tanks, trucks, target boards, and clutter. Employing the biologically-motivated Lambertization and contrast normalization of pixel windows, correlations with multiple Gabor function wavelets, and a 'phase …

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Model-Based 3-D Recognition System Using Gabor Features And Neural Networks, Phung D. Le Dec 1990

Model-Based 3-D Recognition System Using Gabor Features And Neural Networks, Phung D. Le

Theses and Dissertations

A different approach to pattern recognition was attempted using Gabor features, artificial neural nets, and an image generator. The Gabor features and artificial neural nets are sound biological-based, and the image generator provides complete access to any view of an object. This thesis tested the idea that their integration could form a robust 3-D recognition system. The results of the research showed that the Gabor features together with a neural net were used successfully in classifying objects regardless of their positions, out-of- plane rotations, and to a lesser extent in-plane rotations. The Gabor features were obtained by correlating the image …

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Detection Of High Altitude Aircraft Wake Vortices Using Infrared Doppler Lidar: An Assessment, Michael J. Estes Dec 1990

Detection Of High Altitude Aircraft Wake Vortices Using Infrared Doppler Lidar: An Assessment, Michael J. Estes

Theses and Dissertations

This thesis investigated the feasibility of air-to-air detection of high altitude aircraft wake vortices at long ranges using infrared Doppler lidar. The purpose of this technique is to detect otherwise stealthy aircraft. Three laser wavelengths were analyzed: 1.064, 2.091, and 9.115 microns. Analysis revealed that the spectral width of the return signal from an aircraft wake presented a good signature for detection. Based on the analysis, a minimum signal-to-noise ratio of 0 db was established. Detection performance was then analyzed using signal-to-noise ratio calculations for backscatter by ambient atmospheric aerosols, jet engine exhaust soot particles, and condensation trail ice particles. …

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A Compact Optical Associative Memory Using Dynamic Holographic Storage Media And Photorefractive Gain And Attenuation Elements, Thomas J. Burns Dec 1990

A Compact Optical Associative Memory Using Dynamic Holographic Storage Media And Photorefractive Gain And Attenuation Elements, Thomas J. Burns

Theses and Dissertations

This research effort implemented a compact optical associative memory architecture consisting of a Fabry-Perot Confocal Resonator (FPCR) optical processing environment, two dynamically reprogrammable Lithium Niobate volume holograms, and Barium Titanate gain and attenuation elements. The reduced physical dimensions of the compact optical processing environment make it more adaptable to military applications than previous associative memory designs. The FPCR employs Mangin mirrors designed to reduce spherical aberrations in off-axis rays. The orientation of the gain element's grating vector angle and the model used to predict the profile of the attenuation element were unique to this research effort. The object stored in …

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A Comparison Of Human-Computer Interfaces In Air Force Organizations, Michael G. Morris Dec 1990

A Comparison Of Human-Computer Interfaces In Air Force Organizations, Michael G. Morris

Theses and Dissertations

This thesis investigated differences in organizational efficiency and effectiveness for users of graphical user interfaces and text-based interfaces on personal computers in Air Forces offices. Areas of interest included amount of time required to learn the basic system, amount of time required to learn new application, users' ratings of user-friendliness, users' perceptions of the extent that their system help them perform in their job, the number of software packages used on the job by users of each system, user satisfaction, responsible authorities' ratings of quality of output, and the relationship between user job experience level and interface used on the …

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A Whole Word And Number Reading Machine Based On Two Dimensional Low Frequency Fourier Transforms, Mark A. O'Hair Dec 1990

A Whole Word And Number Reading Machine Based On Two Dimensional Low Frequency Fourier Transforms, Mark A. O'Hair

Theses and Dissertations

The Fourier transform is investigated as a means for developing an optical reader capable of reading a large vocabulary without segmenting the image of a word into individual characters. The reader is capable of reading printed and cursive font styles, is scale invariant, and is substantially insensitive to noise. The image of a particular word is treated as a single symbol; the two dimensional low frequency Fourier coefficients (assuming n coefficients are calculated) define the word's location on an n dimensional hypersphere of unit radius. The distance between individual locations (words) categorizes similar and dissimilar words. The smaller the distance, …

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A Performance Predication Model For Parallel Compilers, Ko-Yang Wang Nov 1990

A Performance Predication Model For Parallel Compilers, Ko-Yang Wang

Department of Computer Science Technical Reports

No abstract provided.

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An Interactive Symbolic-Numeric Interface To Parallel Ellpack For Building General Pde Solvers, S. Weerawarana, Elias N. Houstis, John R. Rice Nov 1990

An Interactive Symbolic-Numeric Interface To Parallel Ellpack For Building General Pde Solvers, S. Weerawarana, Elias N. Houstis, John R. Rice

Department of Computer Science Technical Reports

No abstract provided.

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Optimal Superprimitivity Testing For Strings, Alberto Apostolico, Martin Farach, Costas S. Iliopoulos Nov 1990

Optimal Superprimitivity Testing For Strings, Alberto Apostolico, Martin Farach, Costas S. Iliopoulos

Department of Computer Science Technical Reports

No abstract provided.

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Implementation And Performance Of A Communication Facility For Distributed Transaction Processing, Enrique Mafla, Bharat Bhargava Nov 1990

Implementation And Performance Of A Communication Facility For Distributed Transaction Processing, Enrique Mafla, Bharat Bhargava

Department of Computer Science Technical Reports

No abstract provided.

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On Good Triangulations In Three Dimensions, Tamal K. Dey, Chanderjit L. Bajaj, Kokichi Sugihara Nov 1990

On Good Triangulations In Three Dimensions, Tamal K. Dey, Chanderjit L. Bajaj, Kokichi Sugihara

Department of Computer Science Technical Reports

No abstract provided.

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Experiences With Parallelizing A Distributed Database System, Bharat Bhargava, Janche Sang, Yin-He Jiant Nov 1990

Experiences With Parallelizing A Distributed Database System, Bharat Bhargava, Janche Sang, Yin-He Jiant

Department of Computer Science Technical Reports

No abstract provided.

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Managing Data Synchronization Automatically For Distributed-Memory Architectures, Ko-Yang Wang Nov 1990

Managing Data Synchronization Automatically For Distributed-Memory Architectures, Ko-Yang Wang

Department of Computer Science Technical Reports

No abstract provided.

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A Perspective On The Cypress Internetworking Technology, Thomas Narten, Douglas E. Comer, Rajendra Yavatkar Nov 1990

A Perspective On The Cypress Internetworking Technology, Thomas Narten, Douglas E. Comer, Rajendra Yavatkar

Department of Computer Science Technical Reports

No abstract provided.

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Piecewise Linear Approximations Of Digitized Space Curves With Applications, Insung Ihm, Bruce Naylor Nov 1990

Piecewise Linear Approximations Of Digitized Space Curves With Applications, Insung Ihm, Bruce Naylor

Department of Computer Science Technical Reports

No abstract provided.

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Compiling Programs For Nonshared Memory Machines, Charles Koelbel Nov 1990

Compiling Programs For Nonshared Memory Machines, Charles Koelbel

Department of Computer Science Technical Reports

No abstract provided.

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Segment Streaming For Efficient Pipelined Televisualization, Fengmin Gong Nov 1990

Segment Streaming For Efficient Pipelined Televisualization, Fengmin Gong

All Computer Science and Engineering Research

The importance of scientific visualization for both science and engineering endeavors has been well recognized. Televisualization becomes necessary because of the physical distribution of data, computation resources, and users involved in the visualization process. However, televisualization poses a number of challenges to the designers of communication protocols. A pipelined televisualization (PTV) model is proposed for efficient implementation of a class of visualization applications. Central to the proposed research is the development of a segment of streaming IPC (interprocess communication) mechanism in support of efficient pipelining across very high speed internetworks. This requires exploration of special issues arising from extending a …

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Axiomatization Of Some Natural Quantifiers, William C. Purdy Nov 1990

Axiomatization Of Some Natural Quantifiers, William C. Purdy

Electrical Engineering and Computer Science - Technical Reports

This paper extends an existing logic, £n, to some of the generalized quantifiers of natural language. In contrast to the usual approach, this extension does not require the identity relation. Sommers has suggested that the identity is unnecessary in a logic that properly treats singular terms. This paper lends support to Sommers position. £n is a logic designed for natural language reasoning (see [3]). This paper defines an extension, LNQ, of that logic to include the cardinal quantifiers, at least n, and the second-order quantifier, most. Because of the limited expressiveness of first-order languages, a complete axiomatization for most is …

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Hypercube Algorithms For Operations On Quadtrees, Ravi V. Shankar, Sanjay Ranka Nov 1990

Hypercube Algorithms For Operations On Quadtrees, Ravi V. Shankar, Sanjay Ranka

Electrical Engineering and Computer Science - Technical Reports

This paper describes parallel algorithms for the following operations on quadtrees - boolean operations (union, intersection, complement), collapsing a quadtree, and neighbor finding in an image represented by a quadtree. The architecture assumed in this paper is a hypercube with one processing element (PE) per hypercube node. We assume that the architecture is SIMD, i.e., all PEs work under the control of a single control unit.

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Management Of Interdependent Data: Specifying Dependency And Consistency Requirements, Amit P. Sheth, Marek Rusinkiewicz Nov 1990

Management Of Interdependent Data: Specifying Dependency And Consistency Requirements, Amit P. Sheth, Marek Rusinkiewicz

Kno.e.sis Publications

Multiple databases that serve the needs of various application systems are considered. One of the significant problems in managing these databases is to maintain the related data items consistent to the required degree. This problem is frequently referred to as `redundant data management'. Since the term `redundancy' tends to imply that the data is unwanted or superfluous, the authors use the more general term `management of interdependent data'. Some preliminary ideas in this area are discussed. The problem of managing interdependent data is characterized, and some important types of interdatabase dependency are identified.

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