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Theses and Dissertations

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Full-Text Articles in Computer Sciences

Multi-Layered Feedforward Neural Networks For Image Segmentation, Gregory L. Tarr Dec 1991

Multi-Layered Feedforward Neural Networks For Image Segmentation, Gregory L. Tarr

Theses and Dissertations

Artificial neural network image segmentation techniques are examined. The biological inspired cortex transform is examined as a means to preprocess images for segmentation and classification. A generalized neural network formalism is presented as a means to produce common pattern recognition processing techniques in a single iterable element. Several feature reduction preprocessing techniques, based on feature saliency, Karhunen-Loeve transformation and identity networks are tested and compared. The generalized architecture is applied to a problem in image segmentation, a tracking of high- value fixed tactical targets. A generalized architecture for neural networks is developed based on the second order terms of the …


Binary Programming Models Of Spatial Pattern Recognition: Applications In Remote Sensing Image Analysis, Thomas G. Reed Dec 1991

Binary Programming Models Of Spatial Pattern Recognition: Applications In Remote Sensing Image Analysis, Thomas G. Reed

Theses and Dissertations

The major purpose of this investigation was to implement subregion allocation objectives using a network model base on an existing subregion allocation binary programming model (Benabdallah and Wright (B&W), 1990), the ultimate goal being the application of subregion allocation concepts towards the spatial analysis of satellite imagery. The multi-objective aspects of subregion allocation can be accomplished via a network formulation, a formulation vastly simpler in complexity than the binary programming models previously used. Without a network programming package that could maintain integral flows, however, deriving the solution was a tiresome task for the user. Nonetheless, several new concepts and advantages …


Radar System Classification Using Neural Networks, David M. Cameron Dec 1991

Radar System Classification Using Neural Networks, David M. Cameron

Theses and Dissertations

This study investigated methods of improving the accuracy of neural networks in the classification of large numbers of classes. A literature search revealed that neural networks have been successful in the radar classification problem, and that many complex problems have been solved using systems of multiple neural networks. The experiments conducted were based on 32 classes of radar system data. The neural networks were modelled using a program called the Neural Graphics Analysis System. It was found that the accuracy of the individual neural networks could be increased by controlling the number of hidden nodes, the relative numbers of training …


A Formal Definition Of The Object-Oriented Paradigm For Requirements Analysis, Andrew D. Boyd Dec 1991

A Formal Definition Of The Object-Oriented Paradigm For Requirements Analysis, Andrew D. Boyd

Theses and Dissertations

This paper develops a formal definition of the Object-Oriented paradigm for requirements analysis. The literature was surveyed for both formal and informal methods for conducting an Object-Oriented Requirements Analysis (OORA). The informal methods reviewed are: Bailin's, Shlaer and Mellor's, Booch's, and Coad and Yourdon's. The formal methods reviewed are: Bralick's, Z, and REFINE. None of the methods were found to be adequate for doing an OORA. A formal definition of an OORA, based on the concept of classes, is developed. The definition itself is presented as set and relation theory. A supporting graphical representation is also developed and presented. The …


Documentation Requirements For Software Maintenance, Timothy S. Mcarthur Dec 1991

Documentation Requirements For Software Maintenance, Timothy S. Mcarthur

Theses and Dissertations

This study investigated the requirement for documentation during the maintenance phase of the software life cycle. Without proper documentation, maintenance personnel are not able to effectively understand the design of a software system and spend many hours performing design recovery before any type of maintenance can be performed. A review of existing information showed a wide range of opinion among the experts in the field of software maintenance and was not conclusive. A survey of Air Force software maintenance personnel was then conducted to determine the need, availability, and tailoring results of the documents listed on DOD-STD 2167A. The analysis …


Reducing Requirements Errors Through The Use Of Computer-Aided Software Engineering (Case) Tools And During Requirements Analysis, Marvin B. Key Jr. Dec 1991

Reducing Requirements Errors Through The Use Of Computer-Aided Software Engineering (Case) Tools And During Requirements Analysis, Marvin B. Key Jr.

Theses and Dissertations

This study investigated whether using CASE tools in the requirements analysis phase of software development reduced the software coding errors attributable to requirement analysis. A survey of the population gathered data as to the current practices and efforts in the use of CASE tools. The data was gathered in two groups: a control group and a sample group. The data was analyzed by group and in various combinations to obtain a greater understanding into population trends and tendencies. The results of the research indicate that the Air Force does not use CASE tools to any great extent. Also, error and …


Formalization And Validation Of An Sadt Specification Through Executable Simulation In Vhdl, Daniel L. Eickmeier Dec 1991

Formalization And Validation Of An Sadt Specification Through Executable Simulation In Vhdl, Daniel L. Eickmeier

Theses and Dissertations

Formalizing an informal requirements specification, such as SADT, and executing the formal specification in a simulation environment, such as VHDL, provides a requirements analyst a means to validate the behavior of a specification early in the development life cycle. This research effort investigated and demonstrated the feasibility and benefit of transforming an SADT specification of a system into an equivalent VHDL executable simulation. Both non-time related behavior and concurrent, real-time related behavior is addressed. First, a decision table extension to SADT is created so that detailed, executable behavior can be specified. Next a mapping from SADT to VHDL is defined. …


Robotic Tactile Sensors Fabricated From A Monolithic Silicon Integrated Circuit And A Piezoelectric Polyvinylidene Fluoride Thin Film, Craig S. Dyson Dec 1991

Robotic Tactile Sensors Fabricated From A Monolithic Silicon Integrated Circuit And A Piezoelectric Polyvinylidene Fluoride Thin Film, Craig S. Dyson

Theses and Dissertations

The purpose of this research effort was to design, fabricate, and test a tactile sensor system consisting of an external high impedance switch circuit, an external multiplexing circuit, and a tactile sensor IC. In order to accomplish this objective, a hardware design and selection process was implemented along with a logical test methodology. An external multiplexer circuit samples all of the array elements in 50 ms. The current prototype sensor has linearity spanning loads of 0.8 g to 135 g, a load resolution of 20 g, and a maximum bandwidth of 25 Hz. Using an elementary shape recognition algorithm the …


Face Recognition With The Karhunen-Loeve Transform, Pedro F. Suarez Dec 1991

Face Recognition With The Karhunen-Loeve Transform, Pedro F. Suarez

Theses and Dissertations

The major goal of this research was to investigate machine recognition of faces. The approach taken to achieve this goal was to investigate the use of Karhunen-Loe've Transform (KLT) by implementing flexible and practical code. The KLT utilizes the eigenvectors of the covariance matrix as a basis set. Faces were projected onto the eigenvectors, called eigenfaces, and the resulting projection coefficients were used as features. Face recognition accuracies for the KLT coefficients were superior to Fourier based techniques. Additionally, this thesis demonstrated the image compression and reconstruction capabilities of the KLT. This theses also developed the use of the KLT …


Control Of A Large Flexible Space Structure Using Multiple Model Adaptive Algorithms, John A. Gustafson Dec 1991

Control Of A Large Flexible Space Structure Using Multiple Model Adaptive Algorithms, John A. Gustafson

Theses and Dissertations

The development and performance of moving-bank multiple model adaptive estimation (MMAE) and control (MMAC) algorithms for quelling vibrations induced in the SPICE 2 space structure are analyzed in this thesis. The structure consists of a large platform and a smaller platform connected by three legs in a tripod fashion. The model supplied by Phillips Laboratory, Kirtland AFB is used to develop a truth model and multiple reduced ordered filter models. The filter models are developed from modal analysis and internally balanced techniques. Deviations of the line-of-sight vector from the center of the large platform to the center of the smaller …


Real Imagery As A Three Dimensional Display, Juan C. Echeverry Dec 1991

Real Imagery As A Three Dimensional Display, Juan C. Echeverry

Theses and Dissertations

This research effort implemented two 3-D display designs to assess their performance and effect on an observer's depth perception. Both 3-D displays produced real images for the observer to view. The first display setup combined a lens relay with a two concave mirror projector. The second display setup combined the two concave mirror projector with a diffuser. The lens relay/ two concave mirror projector combination was successful in imaging a source from the CRT to a point in space above the two mirror system. The problem was that the observer could not assess the image location by just looking at …


Object-Oriented Analysis And Design Of The Saber Wargame, Christine M. Sherry Dec 1991

Object-Oriented Analysis And Design Of The Saber Wargame, Christine M. Sherry

Theses and Dissertations

This thesis presents an object-oriented analysis and design of Saber, a theater-level computerized wargame, for the Air Force Wargaming Center, Maxwell AFB, Alabama. The analysis and design is based on a recently developed conceptual model, and existing land battle, and additional research. This thesis also begins the implementation process. The design was accomplished using an iterative, five step design process. Objects and operations were chosen and then encapsulated in Ada packages. This thesis also makes necessary changes to the land battle as described by the conceptual model and as the result of additional research. Sound software engineering principles were used …


An Animated Graphical Postprocessor For The Saber Wargame, Gary W. Klabunde Dec 1991

An Animated Graphical Postprocessor For The Saber Wargame, Gary W. Klabunde

Theses and Dissertations

One of the most cost effective ways to learn and home the skills necessary to conduct and win a war is through the use of realistic computer simulations of conflict, or wargames. The Saber wargame was developed for just this purpose. Saber is a multisided, theater-level simulation developed by the Air Force Institute of Technology for the Air Force Wargaming Center. It models conventional, nuclear, and chemical warfare between aggregated air and ground forces. To aid in the realism, the effects of logistics, satellites, weather, and intelligence are represented. Saber provides an avenue for senior level joint service officers to …


An Investigation Of The Application Of Artificial Neural Networks To Adaptive Optics Imaging Systems, Andrew H. Suzuki Dec 1991

An Investigation Of The Application Of Artificial Neural Networks To Adaptive Optics Imaging Systems, Andrew H. Suzuki

Theses and Dissertations

Recurrent and feedforward artificial neural networks are developed as wavefront reconstructors. The recurrent neural network studied is the Hopfield neural network and the feedforward neural network studied is the single layer perceptron artificial neural network. The recurrent artificial neural network input features are the wavefront sensor slope outputs and neighboring actuator feedback commands. The feedforward artificial neural network input features are just the wavefront sensor slope outputs. Both artificial neural networks use their inputs to calculate deformable mirror actuator commands. The effects of training are examined.


An Application Of Interactive Computer Graphics To The Study Of Inferential Statistics And The General Linear Model, Stephen D. Pearce Sep 1991

An Application Of Interactive Computer Graphics To The Study Of Inferential Statistics And The General Linear Model, Stephen D. Pearce

Theses and Dissertations

This research created a learning environment, known as the Pearce Projection Modeling Environment (PPME) which is used as a tool by a teacher and student. The PPME was developed in an effort to create a new approach to the study of the General Linear Model through a constructive and projective, geometric approach. While the geometric approach to the GLM was developed over the past century, it has not been used extensively because of the inherent complexities associated with visualizing vector spaces. With the PPME, visualization is accomplished effortlessly. The PPME is a computer program that allows the student to enter …


Education Necessary For Air Force Software Managers To Use The Ada Programming Language And Software Engineering Effectively, James W. Worley Jr. Sep 1991

Education Necessary For Air Force Software Managers To Use The Ada Programming Language And Software Engineering Effectively, James W. Worley Jr.

Theses and Dissertations

This research investigated the perceived Ada and software engineering education needs of software managers throughout the Air Force and provided recommendations to Air Staff for developing the education. Since the Department of Defense mandated all DOD agencies use the Ada programming language for software development, the education of the personnel who have to support the policy has lagged behind the implementation Ada is not a simple language to use and is only fully effective if used with sound software engineering principles. A survey was given to Air Force mid-level personnel who manage software in some capacity. Of the software personnel …


An Expert System Job Aid For Users Of The Automated Scheduling Module, Kevin A. Gore Sep 1991

An Expert System Job Aid For Users Of The Automated Scheduling Module, Kevin A. Gore

Theses and Dissertations

This research developed an Expert System for novice aircraft maintenance schedulers (AFSC: 392XX) with little experience using the Automated Scheduling Module (ASM). First, an in-depth literature review was completed. Next, personal interviews were conducted with an ASM expert and other 392XX personnel. Prototypes using VP-Expert and KnowledgePro shells were created. The knowledgePro shell was selected to create the ASM Job Aid, combining the knowledge of the expert and AFM 66-279. The program was verified, validated, and favorably reviewed by 392XX personnel. Recommendations include: The Air Force Logistics Management Center (AFLMC) examine the ASM Job AId and develop a Performance Support …


An Application Of Artificial Intelligence Technology Within The Standard Base Supply System, Richard G. Nelson Sep 1991

An Application Of Artificial Intelligence Technology Within The Standard Base Supply System, Richard G. Nelson

Theses and Dissertations

This thesis investigated the feasibility of applying artificial intelligence technology within the Standard Base Supply System (SBSS). With assembly endless reductions in manpower authorizations within the SBSS and the potential for a continued loss of expert knowledge, the use of knowledge-based system (KBSs) was examined to determine if these systems could alleviate this of manpower. Literature related to the fields of artificial intelligence, expert systems, and KBSs was traced, yielding a methodology for identifying candidate problems, and for the development, verification, and validation of prototype KBSs. This methodology was then employed within the research, culminating in the creation, verification, and …


Heuristics For Hospital Inventory Management, Thomas G. Hibson Sep 1991

Heuristics For Hospital Inventory Management, Thomas G. Hibson

Theses and Dissertations

This study investigated the reasoning strategies used by hospital logistics management experts and was conducted at the Wright-Patterson AFB (WPAFB) Medical Center. An expert system was developed to verify the captured strategies. The particular area of interest of this study was the reasoning strategies involved in the reconciliation of the Monthly Stock Status Report within the Medical Logistics Branch. A literature review revealed there were few guidelines as to when and what action to pursue when reconciling the Monthly Stock Status Report. Though there were no references in the literature on expert systems that dealt with this particular report, there …


A Topological Model For Parallel Algorithm Design, Jeffrey A. Simmers Sep 1991

A Topological Model For Parallel Algorithm Design, Jeffrey A. Simmers

Theses and Dissertations

This research demonstrates that formal, mathematical analysis in theoretical computer science can be recast in terms of the topology of complete metric spaces, and also presents a methodical technique for developing formal specifications. This effort shows that the topology of complete metric spaces provides a tool that can be used to both recreate major results about computational models and also to develop new results about these models. Using the two computational models CSP and UNITY, this effort shows that the required mathematics needed to support this alternative to the traditional analysis of computational models can be readily supported by a …


An Ada Based Expert System For The Ada Version Of Satool Ii, Min-Fuh Shyong Jun 1991

An Ada Based Expert System For The Ada Version Of Satool Ii, Min-Fuh Shyong

Theses and Dissertations

This thesis continues the work of implementing the expert system for the Ada version of SAtool II, an software design requirement analysis tool. The background, history, design process together with the design results and validation of the implementation with Ada and CLIPS/Ada is presented.


Transfer Of 4gl Application From Ingres To Oracle, Adnan Altunisik Mar 1991

Transfer Of 4gl Application From Ingres To Oracle, Adnan Altunisik

Theses and Dissertations

This paper documents the transfer of 4GL applications from INGRES to ORACLE. As a result of a fast and conceptual change in computer languages, 4GLs were developed and evolved. These are programming support tools whose goal is, basically, to make the programs more efficient by reducing the number of instructions. Both ORACLE and INGRES database systems use 4GLs to develop applications. Their 4GL environments and their facilities for application development are investigated and explained in depth in this effort. The TWX application, which was originally implemented in INGRES by using its 4GL, is designed and reimplemented in ORACLE. This is …


An Automated Red Player For The Theater Warfare Exercise, Karl W. Kabanek Mar 1991

An Automated Red Player For The Theater Warfare Exercise, Karl W. Kabanek

Theses and Dissertations

The Theater Warfare Exercise (TWX) is a two-sided, theater-level, decision-making exercise created, maintained and used by the personnel at the Air Force Wargaming Center. It is used to allow military officers to practice the decision-making process needed for the wartime employment of air power. An automated player was designed and a prototype implemented for the red (enemy) player using an expert system shell. The automated red player uses the TWX database that contains the data on the different units used in exercise. From the data the automated red player builds mission packages for the various types of missions required in …


A Computer Simulation Of Braitenberg Vehicles, Eric B. Werkowitz Mar 1991

A Computer Simulation Of Braitenberg Vehicles, Eric B. Werkowitz

Theses and Dissertations

In his treatise, Vehicles: Experiments in Synthetic Psychology, Valentino Braitenberg used simple, autonomous vehicle designs to illustrate the principles behind animal nervous system organization and operation. The goal of this effort was to produce a computer program to allow a researcher to experiment with these concepts and to analyze their performance using methods employed by experimental psychologists. The resulting program allows the user to design vehicles that respond to changes in their environments and that have the ability to adapt their behavior, using a learning algorithm developed by Teuvo Kohonen. The vehicle designer is free to select sensor attributes, …


The Boundary Element Method Applied To The Two Dimensional Stefan Moving Boundary Problem, Donald C. Vosika Mar 1991

The Boundary Element Method Applied To The Two Dimensional Stefan Moving Boundary Problem, Donald C. Vosika

Theses and Dissertations

This thesis considers problems for which the boundary is not known before the problem is solved and must be determined as part of the solution. We consider a time dependent problem which results in a moving boundary. We look at the heat conduction/diffusion equation in one and two spatial dimensions. We use Green's Theorem to yield a Volterra boundary integral equation which involves an unknown function on the moving boundary. We use the boundary element method to obtain a solution. Graphical results for the two dimensional problem are presented.


Optimal Iterative Task Scheduling For Parallel Simulations, Joann M. Sartor Mar 1991

Optimal Iterative Task Scheduling For Parallel Simulations, Joann M. Sartor

Theses and Dissertations

The ultimate purpose of this research is to reduce the time needed for execution of parallel computer simulations. In particular, the impact of task assignment strategies is determined for parallel VHDL circuit simulations. The classical scheduling problem, which assigns n precedence-constrained tasks to m processors is NP-complete in all but the simplest cases. The problem of assigning simulation tasks is further complicated by the iterative nature of computer simulations: each task is required to execute multiple times as the simulation executes. This investigation develops a polynomial-time algorithm (the level strategy) which provides optimal assignment for iterative systems with specific constraints. …


The Problem Of Mutual Exclusion: A New Distributed Solution, Rajeev Chawla Jan 1991

The Problem Of Mutual Exclusion: A New Distributed Solution, Rajeev Chawla

Theses and Dissertations

In both centralized and distributed systems, processes cooperate and compete with each other to access the system resources. Some of these resources must be used exclusively. It is then required that only one process access the shared resource at a given time. This is referred to as the problem of mutual exclusion. Several synchronization mechanisms have been proposed to solve this problem. In this thesis, an effort has been made to compile most of the existing mutual exclusion solutions for both shared memory and message-passing based systems. A new distributed algorithm, which uses a dynamic information structure, is presented to …


Three Degrees Of Freedom Compliant Motion Control For Robotic Aircraft Refueling, Clayton M. Andersen Dec 1990

Three Degrees Of Freedom Compliant Motion Control For Robotic Aircraft Refueling, Clayton M. Andersen

Theses and Dissertations

The Air Force Institute of Technology (AFIT) supports on-going research in application of robotic technology to enhance assembly tasks. As a testbed, AFIT supports the ground-based aerial refueling project, with an emphasis on visual servoing techniques and compliant motion control. This thesis focuses on compliant motion control. Previous research developed the testing environment, which includes a PUMA-560 industrial manipulator, and a half scale mock-up of an aerial refueling system. This effort corrected and expanded the existing two degree of freedom (DOF) compliant controller to three DOF. Three DOF compliance was demonstrated by inserting the refueling nozzle into the receiver port. …


Computer Model Of An Injection Locked Pulsed Co2 Laser, Allen M. Susie Dec 1990

Computer Model Of An Injection Locked Pulsed Co2 Laser, Allen M. Susie

Theses and Dissertations

With the discovery of the laser there have been continual attempts to increase the 'spectral brightness' of a laser for applications such as signal processing and lidar. To this end techniques using either passive or active cavity elements have been developed to isolate a single longitudinal mode in both continuous and pulsed laser systems. Although passive elements have useful applications in continuous systems their use in pulsed systems is difficult to control. The injection of an external signal has proved very successful.


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 …