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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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Mapping An Object-Oriented Requirements Analysis To A Design Architecture That Supports Design And Component Reuse, Kelly L. Spicer Dec 1990

Mapping An Object-Oriented Requirements Analysis To A Design Architecture That Supports Design And Component Reuse, Kelly L. Spicer

Theses and Dissertations

Design reuse has more potential for increasing the productivity of software development and maintenance than do traditional approaches to software reuse that emphasize reuse of smaller components. Current software development methods do not promote design reuse. The literature contains limited documented research on the subject, but enough that some design reuse principles can be gleaned. Among these principles are that reusable designs should be applicable within some domain of application, have a consistent structure, provide a method for instantiating the design, avoid object nesting, and promote reuse of smaller components as well. A design mapping method from an object-oriented requirements …

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An Ada-Based Framework For An Idef0 Case Tool Using The X Window System, Jay-Evan J. Tevis Ii Dec 1990

An Ada-Based Framework For An Idef0 Case Tool Using The X Window System, Jay-Evan J. Tevis Ii

Theses and Dissertations

This thesis documents the design strategy, implementation methodology, testing, and evaluation used in developing an Ada-based framework for SAtool II using the X Window System. SAtool II is an IDEF0 graphical project editor and data dictionary editor. An Ada-Based Framework for an IDEF0 Case Tool Using the X Window System is the ICAM Definition Method Zero graphical notation language adopted by the U.S. Air Force to produce a function model of a manufacturing system or environment (23:1-1). The Air Force Institute of Technology is conducting on-going research in the use of IDEF0 in the requirements analysis phase …

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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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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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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 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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Optical Image Segmentation Using Wavelet Filtering Techniques, Christopher P. Veronin Dec 1990

Optical Image Segmentation Using Wavelet Filtering Techniques, Christopher P. Veronin

Theses and Dissertations

This research effort successfully implemented an automatic, optically based image segmentation scheme for locating potential targets in a cluttered FLIR image. Such a design is critical to achieve real-time segmentation and classification for machine vision applications. The segmentation scheme used in this research was based on texture discrimination and employs orientation specific, bandpass spatial filters as its main component. The orientation specific, bandpass spatial filters designed during this research include symmetrically located circular apertures implemented on heavy, black aluminum foil; cosine and sine Gabor filters implemented with detour-phase computer generated holography photoreduced onto glass slides; and symmetrically located circular apertures …

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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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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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Nonlinear Interferometry: Optical Image Addition/Subtraction And Novelty Filters, Gordon T. Hengst Dec 1990

Nonlinear Interferometry: Optical Image Addition/Subtraction And Novelty Filters, Gordon T. Hengst

Theses and Dissertations

This thesis investigated the performance characteristics of a beam fanning novelty filter and designed a switchable optical image adder/subtractor. The filter spatial resolution, contrast ratio, onset time, and velocity response were measured for both z-cut and 45 deg. cut BaTiO3 crystals in the beam fanning configuration. Experimental results show that the special 45 deg. cut crystal produces the best overall beam fanning novelty filter. In addition, switchable optical image subtraction and addition were demonstrated for the first time using a modified Michelson interferometer configured with a phase-conjugating mirror and an adjustable length leg. The system demonstrated addition and subtraction with …

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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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Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, November 1990, College Of Engineering And Computer Science, Wright State University Nov 1990

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, November 1990, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

A ten page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

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Parallel Vision Algorithms Using Sparse Array Representations, Ravi V. Shankar Nov 1990

Parallel Vision Algorithms Using Sparse Array Representations, Ravi V. Shankar

Electrical Engineering and Computer Science - Technical Reports

Sparse arrays are arrays in which the number of non-zero elements is a small fraction of the total number of array elements. This paper presents computer vision algorithms using sparse representations for arrays. The parallel architecture considered is a hypercube. The algorithms can be easily modified for other architectures like the mesh. We assume that the architecture is SIMD, i.e., all PEs work under the control of a single control unit.

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Forecasting The Behavior Of Multivariate Time Series Using Neural Networks, Kanad Charkraborty, Kishan Mehrotra, Chilukuri K. Mohan, Sanjay Ranka Nov 1990

Forecasting The Behavior Of Multivariate Time Series Using Neural Networks, Kanad Charkraborty, Kishan Mehrotra, Chilukuri K. Mohan, Sanjay Ranka

Electrical Engineering and Computer Science - Technical Reports

This paper presents a neural network approach to multivariate time-series analysis. Real world observations of flour prices in three cities have been used as a benchmark in our experiments. Feedforward connectionist networks have been designed to model flour prices over the period from August 1972 to November 1980 for the cities of Buffalo, Minneapolis, and Kansas City. Remarkable success has been achieved in training the networks to learn the price curve for each of these cities, and thereby to make accurate price predictions. Our results show that the neural network approach leads to better predictions than the autoregressive moving average(ARMA) …

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