Digital Commons Network^™

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 …

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 Expert System For Measuring, Interpreting, And Managing System Performance Factors For The Work Information Management System, Billy J. C. Irwin

Theses and Dissertations

This study develops an expert system for measuring, interpreting, and managing the Wang VS operating system performance factors for the Work Information Management System. The system's performance concerns least known to system administrators are identified. Of these, SHARER buffers and VTOC cache are identified as factors that can significantly impact system performance with little effort. A six step process is used in developing the expert system. Concept maps representing the structure of the Wang VS Disk Input/Output problem domain are provided. The expert system provides information about the system parameters, SHARER buffers and VTOC cache, and recommends main memory allocations. …

Relative Utility Of Selected Software Requirement Metrics, James H. Byers

Theses and Dissertations

The objective of this study was to determine the relative utility of selected software requirement metrics in assessing the productivity of the software requirements analysis process and the quality of the products of this process. This objective was met by collecting information about the perceptions that practicing software professionals have of the usefulness of various requirement metrics. The study employed a two part methodology. The first part utilized Basili's goal/question/metric paradigm to identify specific goals of the measurement effort and to identify requirement metrics worthy of further investigation. The second part employed a typical research design to gather perceptions that …

Possible Application Of Quality Function Deployment In Software Systems Development In The United States Air Force, Craig R. Lamb

Theses and Dissertations

The objectives of the thesis were to determine whether the methods of Quality Function Deployment (QFD) could be used in the software development environment within the USAF, and whether or not this area should be researched further. The research was limited to the requirements analysis and definition phase. The different areas of study included a brief review of the structured analysis methodology, a detailed review of the QFD models currently being used in the product industries, a review of how QFD fits into the software development cycle, and specific software modifications to the QFD methodology. A review of some applications …

Investigative Search Of Quality Historical Software Support Cost Data And Software Support Cost-Related Data, Brent L. Barber

Theses and Dissertations

The purpose of the study was to determine what software support cost data and software support cost-related data should and can be collected by the Air Force. In addition, the study was to determine how the subject data should be collected. The collection of this data is necessary in order to measure the accuracy and calibration requirements of the software support cost models used by the Air Force. The study found there was no standard set of data items, and no standard procedures in place for the collection of this data. In most cases data were available or easily accessible, …

An Expert System Advisor For Medical Evaluation Boards, Jerry S. G. Harrington

Theses and Dissertations

Expert system technology has proven itself to be able to improve productivity and decision making in a variety of fields of endeavor. The purpose of this study was to determine if an expert system for medical evaluation boards (MEBs) could improve upon the processing of medical evaluation board cases. Research was conducted to develop an expert system and measure the capabilities of the system, both in terms of accuracy and timeliness of case completion of the medical evaluation administrators/clerks who were assisted by the system. The research methodology involved a three - phase approach. The objective of phase one was …

Design And Application Of An Object Oriented Graphical Database Management System For Synthetic Environments, John A. Brunderman

Theses and Dissertations

The Air Force Institute of Technology (AFIT) is investigating the use of synthetic environments for military applications under the sponsorship of Rome Laboratories (RL). Areas under investigation include mission planning, battle management and flight simulation. The work reported in this thesis focuses on the object-oriented design and implementation of the Graphical Database Management System (GDMS) used to support research in these areas. GDMS provides the data structures, file format and algorithms to manage and render hierarchical, three-dimensional, polygonal models. Flexibility and adaptability were key factors in its design. A secondary objective of this research was to demonstrate the functionality of …

Logic Programming In Digital Circuit Design, Joseph W. Eicher

Theses and Dissertations

The design of large, complex digital circuitry requires highly skilled engineers. Much of the time spent by these engineers in the design phase involves tasks that are repetitive, tedious, and slow. If these repetitive tasks are automated, the engineer can spend more time managing the design process and produce a better-quality design in less time. Logic programming can be used to automate design tasks, even those that require a high degree of skill. This thesis investigates several aspects of the digital circuit design process that involve pattern-matching paradigms suitable for encoding in the logic programming language Prolog.

Parallel Implementation Of Vhdl Simulations On The Intel Ipsc/2 Hypercube, Ronald C. Comeau

Theses and Dissertations

VHDL models are executed sequentially in current commercial simulators. As chip designs grow larger and more complex, simulations must run faster. One approach to increasing simulation speed is through parallel processors. This research transforms the behavioral and structural models created by Intermetrics' sequential VHDL simulator into models for parallel execution. The models are simulated on an Intel iPSC/2 hypercube with synchronization of the nodes being achieved by utilizing the Chandy Misra paradigm for discrete-event simulations. Three eight-bit adders, the ripple carry, the carry save, and the carry-lookahead, are each run through the parallel simulator. Simulation time is cut in at …

An Event Driven State Based Interface For Synthetic Environments, Mark J. Gerken

Theses and Dissertations

Previous research at the Air Force Institute of Technology (AFIT) has produced synthetic environments using head mounted displays (HMDs) and hand measurement devices. This thesis is a continuation of AFIT synthetic environment research. Hand measurement data from a VPL DataGlove is combined with hand orientation and translational data to define a set of valid gestures. These gestures form the basis of an input language for class of finite automata known as finite state machines. Using the input symbols from this language, the user may define a finite state machine which associates a stream of input symbols with one or more …

Design And Implementation Of A Graphical User Interface And Database Management System For The Saber Wargame, Andrew M. Horton

Theses and Dissertations

Saber is a theater level, multi-sided, airpower employment computerized wargame that can be programmed to simulate any combat scenario. The model simulates theater level combat between air and land forces, and takes into account the effects of logistics, resupply, and both theater nuclear and chemical warfare. The major objective of the Saber model is to provide a suitable educational platform to allow users to apply basic, tactical employment concepts to multiple combat units, each having a specialized mission, and incorporating every branch of the armed services. This thesis documents a graphical user interface and data management system that has been …

Enhanced Animation Of Parallel Algorithms, Michael D. Lack

Theses and Dissertations

Algorithm animation is a visualization method used to enhance understanding of the functioning of an algorithm or program. Visualization is used for many purposes, including education, algorithm research, performance analysis, and program debugging. This research, which follows from previous work, examines algorithm animation requirements for the various visualization purposes and extends the capabilities of an existing facilities, the AFIT algorithm Animation Research Facility (AAARF). The structure of AAARF is summarised and its visualization capabilities presented, analysed and compared with other similar packages. This research focuses on the parallel data requirements of the AAARF users, and the meaningful display of large …

Graph-Based Visualization Of Formal Specification And Domain Specific Languages, Randel K. Langloss

Theses and Dissertations

This research develops and implements Visual Refine, a graph-based visualization system, for the Refine wide-spectrum formal specification language and environment developed and marketed by Reasoning Systems, Inc. Refine specifications are represented in the Refine object base as abstract syntax trees (AST). Using these AST representations, one-to-one mappings are defined between nodes of the AST and the graphical icons of Visual Refine. Visual Refine uses these mappings to implement a set of formal transformations. Each transformation is encapsulated within a Refine rule, and this set of rules form the Visual Refine transformation system. The Visual Refine transformation system, in conjunction with …

A Spatially Partitioned Parallel Simulation Of Colliding Objects, Robert S. Moser

Theses and Dissertations

This study investigated the application of a conservative synchronization paradigm to the classical, distributed pool balls simulation executed on an eight node, Intel iPSC/2 hypercube. Wieland's concept of spatial partitioning and limited data replication was used. Analysis has shown that 100% parallelization of execution is possible in a conservative environment via assignment of multiple sectors to nodes. Two conservative formulations for minimum safe time were derived. A tradeoff exists between scalability and efficiency. Optimum sectoring prediction has been shown possible through application of linear regression techniques. The results of this research reveal that a conservative approach to distributed, discrete event …

Three-Dimensional Medical Image Registration Using A Patient Space Correlation Technique, Patrick J. Rizzuto Jr.

Theses and Dissertations

The routine clinical use of three-dimensional data provided by modern medical imaging procedures is often impeded by the difficulty in accurately correlating the resultant volume datasets. These data are frequently obtained at different times using the same modality, or images of the same patient are sometimes produced using more than one imaging modality. In order to analyze the similarities and differences between such images, it is necessary for the medical imaging data to be spatially aligned using a process known as image registration. This research investigated a structure-based image registration technique based upon simple, three-dimensional relationships among user identified landmarks. …

Design Of Style-V — A Translator To Convert Standard Vhdl Into A Stylized Form For Automated Microcode Generation, Dennis A. Rumbley

Theses and Dissertations

This thesis provides an analysis and preliminary design of Style V, a source-to-source computer language translator. Style-V converts IEEE standard VHDL into a special style of VHDL defined for a commercial tool, the Integrated Design Automation System (IDAS). Thirteen mappings between standard VHDL and the IDAS subset were identified. The mappings were analyzed using Domain Analysis and Modern Structured Analysis techniques. Four processes covering several of the mappings were completely analyzed. One mapping to convert CASE statements to IF statements was implemented. Since the IDAS restricts designs to bit logic, a method for representing multilevel logic with bit logic was …

Effect Of Spatial Locality Prefetching On Structural Locality, Dirk D. Schalch

Theses and Dissertations

The purpose of this research was to analyze the effect that spatial locality prefetching in cache memory has on the structural locality of program memory referencing behavior. To examine this, a software simulator was built to model a proposed two-level cache memory subsystem. The proposed subsystem was designed to use spatial locality prefetching to exploit the structural locality contained in executing computer workloads. New memory referencing models were developed to incorporate the combined use of structural locality and spatial locality prefetching. From these models, equations were derived to predict the hit rates for both caches. Combined with the state transition …

Parallelizing Serial Code For A Distributed Processing Environment With An Application To High Frequency Electromagnetic Scattering, Paul R. Work

Theses and Dissertations

This thesis investigates the parallelization of existing serial programs in computational electromagnetics for use in a parallel environment. Existing Algorithms for calculating the radar cross section of a object are covered, and a ray-tracing code is chosen for implementation on a parallel machine. Current parallel architectures are introduced and a suitable parallel machine is selected for the implementation of the chosen ray tracing algorithm. The standard techniques for the parallelization of serial code are discussed, including load balancing and decomposition considerations, and appropriate methods for the parallelization effort are selected. A load balancing algorithm is modified to increase the efficiency …

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 …

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.

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 …

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 …

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 …

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

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 …

Optimal Parallel Algorithms For Periods, Palindromes And Squares (Preliminary Version), Alberto Apostolico, Dany Breslauer, Zvi Galil

Department of Computer Science Technical Reports

No abstract provided.

Availability Issues In Data Replication In Distributed Database, Donald B. Johnson, Larry Raab

Computer Science Technical Reports

Replication of data at more than one site in a distributed database has been reported to increase the availability in data in systems where sites and links are subject to failure. We have shown in results summarized in this paper that in many interesting cases the advantage is slight. A well-placed single copy is available to transactions almost as much of the time as is correct replicated data no matter how ingeniously it is managed. We explain these findings in terms of the behavior of the partitions that form in networks where components fail. We also show that known and …

An Organization Of Sparse Gauss Elimination For Solving Pdes On Distributed Memory Machines, Mo Mu, John R. Rice

Department of Computer Science Technical Reports

No abstract provided.

An Lr(L) Testing Algorithm, Thomas J. Ssager

Computer Science Technical Reports

A grammar is LR{1} if it can be parsed deterministically from left to right while looking ahead no more than one symbol. Because of the difficulty in generating full LR{l) parsers, many parser generators such as YACC limit themselves to LALR(1} grammars which are a subset of the LR{l) grammars.

Unlike other algorithms in the literature for testing whether a grammar is LR{l), the algorithm presented here uses only the characteristic finite state machine and other structures necessary for creating an LALR{l) parser. Thus, if a parser generator finds that a grammar is not LALR{l), with little additional work the …