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Air Force Institute of Technology

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Articles 2581 - 2610 of 2678

Full-Text Articles in Physical Sciences and Mathematics

An Environmental Audit Management Plan For The Royal Australian Air Force, Warren L. Lear Sep 1992

An Environmental Audit Management Plan For The Royal Australian Air Force, Warren L. Lear

Theses and Dissertations

The purpose of this research was to develop an Environmental Audit Management Plan (EAMP) tailored to meet the specific requirements of the Royal Australian Air Force (RAAF). The research also examined the resources which would be required to introduce the proposed EAMP into the RAAF. The literature on environmental compliance auditing identifies a number of essential characteristics required for an effective environmental auditing program. These characteristics, in conjunction with the USEPA design guidelines for the development of audit programs for government agencies, were used to guide the development of the RAAF EAMP. Information on Australian environmental legislation, DOD/RAAF policies and …

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Autonomous Face Segmentation, Kevin P. Gay Sep 1992

Autonomous Face Segmentation, Kevin P. Gay

Theses and Dissertations

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

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Comparative Evaluation Of A Monocular Head Mounted Display Device Versus A Flat Screen Display Device In Presenting Aircraft Maintenance Technical Data, Jeffrey A. Friend, Randy S. Grinstead Sep 1992

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

Theses and Dissertations

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

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The Application Of Function Points To Predict Source Lines Of Code For Software Development, Garland S. Henderson Sep 1992

The Application Of Function Points To Predict Source Lines Of Code For Software Development, Garland S. Henderson

Theses and Dissertations

This research investigated the results of using function point analysis-based estimates to predict source lines of code (SLOC) for software development projects. The majority of software cost and effort estimating parametric tools are categorized as SLOC-based, meaning SLOC is the primary input. Early in a program, an accurate estimate of SLOC is difficult to project. Function points, another parametric software estimating tool, bases software cost and effort estimates on the functionality of a system. This functionality is described by documents available early in a program. Using a modeling methodology, the research focuses on function point's ability to accurately estimate SLOC …

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Development Of A Standard Set Of Software Indicators For Aeronautical Systems Center, Bradley J. Ayres, William M. Rock Sep 1992

Development Of A Standard Set Of Software Indicators For Aeronautical Systems Center, Bradley J. Ayres, William M. Rock

Theses and Dissertations

This research effort was directed to the development of a standard set of software indicators to be used by ASC. The research was sponsored by ASC/ENASC, who indicated their desire for such a standard set of indicators to allow a database to be developed of program data that would be useful in making predictions about future software efforts. The research began with an attempt to characterize the software indicator environment at ASC, and also to perform a literature search for software indicators currently available. The desired result was an initial core set of indicators useful to software managers and engineers …

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The Development Of An Expert System For Hazardous Cargo Compatibility, Douglas A. Furst, Ronald E. Smith Sep 1992

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

Theses and Dissertations

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

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Examination Of Psychological Type And Preferred Negotiation Tactics And Strategies Of Contract Negotiators, John P. Hebert, Alan J. Meade Sep 1992

Examination Of Psychological Type And Preferred Negotiation Tactics And Strategies Of Contract Negotiators, John P. Hebert, Alan J. Meade

Theses and Dissertations

This research identified the psychological types of government and industry contract negotiators and determined whether their preference for using negotiation tactics and strategies were correlated with their respective psychological types. A survey consisting of the Myers-Briggs Type Indicator (MBTI) and a questionnaire concerning use of negotiation tactics and strategies was mailed to 2,000 contracting professionals of the National Contract Management Association (NCMA). During May and June 1992, 627 usable surveys were received. The MBTI results were paired with the responses to the negotiation tactics and strategies questionnaire. These results were analyzed on a microcomputer using the DBase IV, Excel, and …

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Design Of An Artificial Neural Network Based Tactile Sensor For The Utah/Mit Dexterous Hand, Jeffery D. Nering Sep 1992

Design Of An Artificial Neural Network Based Tactile Sensor For The Utah/Mit Dexterous Hand, Jeffery D. Nering

Theses and Dissertations

The Neural Tactile Sensor (NTS) is a high resolution, easily manufactured tactile sensor consisting of electrodes, a thin resistive 'skin', and pattern recognition circuitry that is capable of resolving dynamic and static contact location, force, and slip throughout the continuum of the sensor's active region. The sensor operates by means of a resistive 'skin' harboring the electric field generated when a current is injected into it, and a plurality of electrodes for taking measurements of said electric field. When current flows through the resistive medium from the location of tactile contact, an electric field within the resistive medium is established, …

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Development Of An Environment For Software Reliability Model Selection, Salah A. Elewa Sep 1992

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

Theses and Dissertations

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

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The Development Of A Performance Measurement Concept For The Royal Australian Air Force, David R. Mcdonald Sep 1992

The Development Of A Performance Measurement Concept For The Royal Australian Air Force, David R. Mcdonald

Theses and Dissertations

he Royal Australian Air Force (RAAF) needed to develop performance measurements (PMs) to support its Program Management and Budgeting (PMB) System. This research assessed the use of the concepts of the Theory of Constraints (TOC) to develop those PMs. The literature indicated that: traditional accounting PMs were not always suitable in an environment of continuous improvement; Activity Based Costing did not provide the required measures; and non-financial PMs were supplanting the older measures. Further, governments faced unique problems in developing PMs, particularly in defining the outcomes to be measured. Using the Critical Theory and Action Research methodologies, and a case …

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Comparison Of Four-Cursor Buttons Vs Joystick To Access Computerized Technical Information From An Integrated Maintenance Information System, Gerald E. Streff, Robert H. Gundel Sep 1992

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

Theses and Dissertations

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

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Award Fee In Software Acquisition, Mark T. Hunter Sep 1992

Award Fee In Software Acquisition, Mark T. Hunter

Theses and Dissertations

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

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Photoluminescence Study Of Si1-XGeX/Si And Si/Ge Strained Layer Superlattices, Todd D. Steiner Jul 1992

Photoluminescence Study Of Si1-XGeX/Si And Si/Ge Strained Layer Superlattices, Todd D. Steiner

Theses and Dissertations

In recent years, there has been interest in obtaining efficient photoluminescence (PL) and electroluminescence from Si1-xGex/Si or Si/Ge superlattices. In this dissertation, longperiod c/Si superlattices grown by molecular beam epitaxy at 500°C and annealed post-growth using rapid thermal annealing were investigated using photoluminescence (PL). The as-grown samples have broad PL bands from isoelectronic centers related to Ge complexes as well as sharp near-edge bound exciton lines. The broad PL band was found to be 120 meV below the band gap, after accounting for the effects of confinement of holes. Post-growth annealing resulted in a reduction in …

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Multi-Ion Ambipolar Diffusion, Thomas E. Gist Jul 1992

Multi-Ion Ambipolar Diffusion, Thomas E. Gist

Theses and Dissertations

The continuity and momentum equations for electrons and multiple ion species are solved analytically and numerically using a new model for ambipolar diffusion. The general form of the model is valid for any quasi-neutral plasma for which the diffusion approximation is appropriate, including positive or negative ions, arbitrary geometries, and time dependence. The model provides criteria for determining when single ion diffusion theory is appropriate for describing multi-ion discharges, when a multi-ion proportional model is appropriate, and when a multi-ion nonproportional model is necessary. An expression is developed which provides a necessary condition for proportionality and provides the proportionality constant …

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Design Of A Laboratory Computer Interface, Douglas L. Durand Jun 1992

Design Of A Laboratory Computer Interface, Douglas L. Durand

Theses and Dissertations

An interface for the LSI-11 computer was designed and implemented so that the computer supports data acquisition, data reduction, and equipment control. The design includes both hardware and software and addresses both parallel and serial input/output (I/0). The serial interface's hardware is simply a Serial Line Unit card. This card plugs into the LSI-11 bus and provides the signals necessary to interface EIA RS-232 compatible devices. A software utility was developed to allow communication with the serial device and to allow exchange of data files. Routines were written to allow serial I/O through a FORTRAN program. The interface's parallel hardware …

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Feature Extraction And Classification Of Flir Imagery Using Relative Locations Of Non-Homogeneous Regions With Feedforward Neural Networks, Kevin L. Priddy Apr 1992

Feature Extraction And Classification Of Flir Imagery Using Relative Locations Of Non-Homogeneous Regions With Feedforward Neural Networks, Kevin L. Priddy

Theses and Dissertations

The classification of forward looking infrared (FLIR) imagery is explored using Gabor transform decomposition and relative locations of non- homogeneous regions combined with feedforward neural networks. A feature saliency metric is developed from a Bayesian sensitivity analysis of feedforward neural networks. This metric is then used to reduce the dimensionality of the feature vectors used to identify FLIR imagery without any degradation of classification accuracy. Several system architectures are developed using a roving window combined with a series of Gabor filters to produce feature vectors for presentation to a neural network classifier. One architecture uses the Gabor filter coefficients to …

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Transformation Of Combat Data In Support Of Battle Trace, Hyoung-Kyu Choi Mar 1992

Transformation Of Combat Data In Support Of Battle Trace, Hyoung-Kyu Choi

Theses and Dissertations

The purpose of this study was to find an appropriate way of characterizing battle data as a function of time. This study was initially designed to remove the numerical instability problem cited in Barr's battle trace methodology as suggested by TRAC-MTRY. The research focused on the instability problem and identifying/recommending a technique that improved the efficiency of computation, and enhanced an analyst's ability to meaningfully interpret the battle trace. Two Lanchester's Square Law based methodologies are introduced and analyzed. The results of this analysis indicate that the battle trace of a constant value generated by Lanchester's Square Law integration seemed …

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A Sensitivity Analysis Of Circular Error Probable Approximation Techniques, Peter Puhek Mar 1992

A Sensitivity Analysis Of Circular Error Probable Approximation Techniques, Peter Puhek

Theses and Dissertations

Several algebraic CEP estimates models were examined in this study. Each assumes that the crossrange and downrange miss distances of the sample data follow a bivariate normal distribution. The analysis determined the sensitivities of these models to changes in the parameters of sample size, bias, correlation, and ellipticity. The accuracy of each model is expressed in terms of relative error, and the parameter regions in which a certain method dominated as the most accurate were noted. In general, it was found that bias was the most significant parameter in determining the best CEP method. A simple method, based on the …

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Implementation And Analysis Of Np-Complete Algorithms On A Distributed Memory Computer, Joel S. Garmon Mar 1992

Implementation And Analysis Of Np-Complete Algorithms On A Distributed Memory Computer, Joel S. Garmon

Theses and Dissertations

The purpose of this research is to explore methods used to parallelize NP-complete problems and the degree of improvement that can be realized using different methods of load balancing. A serial and four parallel A* branch and bound algorithms were implemented and executed on an Intel iPSC/2 hypercube computer. One parallel algorithm used a global, or centralized, list to store unfinished work and the other three parallel algorithms used a distributed list to store unfinished work locally on each processor. the three distributed list algorithms are: without load balancing, with load balancing, and with load balancing and work distribution. The …

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Development Of A System For Survey Of Radon Concentration Of The Dayton Area Using A Liquid Scintillation Counter And Analysis Of The Data, Taewon Kim Mar 1992

Development Of A System For Survey Of Radon Concentration Of The Dayton Area Using A Liquid Scintillation Counter And Analysis Of The Data, Taewon Kim

Theses and Dissertations

A system to do a large scale survey was developed. The data obtained from the survey was analyzed using a database. The database incorporated an equation for converting cpm into radon concentration pCi/ℓ). The equation of conversion, protocol for measuring radon concentration, survey form, and a database program were modified (from previous theses) or developed for this thesis. The elution time constant, adsorption time constant, and calibration factor were calculated for equation of conversion. Two surveys were during the course of the thesis. On the first survey, the arithmetic average radon concentration with standard error of the mean was 2.9 …

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An Examination Of Hypercube Implementations Of Genetic Algorithms, Andrew Dymek Mar 1992

An Examination Of Hypercube Implementations Of Genetic Algorithms, Andrew Dymek

Theses and Dissertations

Genetic algorithms are stochastic search algorithms which model natural adaptive systems. In support of the development of a genetic search package for AFIT's iPSC/2 Hypercube, this study focused on two problem areas associated with hypercube implementations. Premature convergence occurs when the population becomes dominated by locally optimal, but globally inferior, solutions. Based on an examination of past hypercube implementations, the selection and communication strategies were hypothesized as causes of premature convergence. Experiments to test these hypotheses were conducted on Rosenbrock's saddle, a function often associated with premature convergence. Communication of best solutions led to premature convergence in small population sizes, …

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Numerical Analysis Of Plasma Transport In Tandem Volume Magnetic Multicusp Ion Sources, Todd R. Vitko Mar 1992

Numerical Analysis Of Plasma Transport In Tandem Volume Magnetic Multicusp Ion Sources, Todd R. Vitko

Theses and Dissertations

A one-dimensional fluid model of plasma transport in tandem volume magnetic multicusp ion sources is explored. The model, the positive ion source code pos, by Glasser and Smith, calculates plasma density, drift velocity, electron temperature, and ion temperature in an ion source. The usefulness of the model is limited: (1) The plasma density trend runs opposite to experimental results, and electron temperatures are an order of magnitude higher than experimentally observed. (2) simplification of the reaction chemistry leads to a plasma balance between ionization and outflow instead of the correct balance between ionization and recombination. (3) Wall losses are …

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Shock Tube Simulation By The Smooth Particle Hydrodynamic (Sph) Method, Luke A. Lorang Mar 1992

Shock Tube Simulation By The Smooth Particle Hydrodynamic (Sph) Method, Luke A. Lorang

Theses and Dissertations

A smooth particle hydrodynamic code (SPHC) is evaluated for performing shock wave simulations by application to 1-D shock tube problems. Results of a shock tube test case with a compression ratio of 10 are compared against a Riemann shock tube problem and theoretical predictions of shock tube behavior to validate the SPH code. A Lagrangian hydrodynamic code is validated in a similar fashion. The resolution capabilities of both codes are compared using 100, 200 and 500 particles for SPHC and 100, 400 and 800 cells for the Lagrangian code. The SPH code exhibits a sharp spike in density at the …

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Multilayer Perceptrons For Classification, Lisa M. Belue Mar 1992

Multilayer Perceptrons For Classification, Lisa M. Belue

Theses and Dissertations

Techniques for training, testing, and validating multilayer perceptrons are thoroughly examined. Results obtained using perceptrons are compared and contrasted with two multivariate discriminant analysis techniques- logistic regression and k neighbor. Methods for determining significant input features are investigated and a procedure for examining the confidence to place in the significance of these features is developed. Procedures to evaluate the applicability of high-order feature inputs are examined. These methods and procedures are applied to two very different applications. The first application concerns the prediction of Air Force pilot retention/separation rates for input to force projection models. The second application concerns the …

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Confidence Interval Estimation For Output Of Discrete-Event Simulations Using The Kalman Filter, Randall B. Howard Mar 1992

Confidence Interval Estimation For Output Of Discrete-Event Simulations Using The Kalman Filter, Randall B. Howard

Theses and Dissertations

Discrete-event simulation is computer modeling of stochastic, dynamic systems. The Kalman filter is a Bayesian stochastic estimation algorithm. Because of the correlated nature of simulation output, it is difficult to apply the methods of classical statistics directly when constructing confidence intervals of discrete-event simulation parameters. Through the determination of a dynamics equation and application of the Kalman filter to simulation output data, three new confidence interval construction techniques have been developed. One technique obtains an estimate of the mean value and its associated variance from an estimated Kalman filter. The second technique utilizes Multiple Model Adaptive Estimation (MMAE) techniques to …

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Hardware-Verification Through Logic Extraction, Michael A. Dukes Mar 1992

Hardware-Verification Through Logic Extraction, Michael A. Dukes

Theses and Dissertations

A Prolog-based system is described which employs logic-extraction to perform hardware-verification. The extraction rules are built automatically from hierarchical structural VHDL models, enabling the equivalence of a structural VHDL description and a layout specification to be verified. Pin-to-pin critical- path analysis is performed within the logic-extraction process; many noncritical paths are pruned early, making pin-to-pin critical path analysis of large circuits feasible. It is demonstrated that a design methodology based on logic extraction, VHDL, and a layout tool can provide a fabricated functionally- correct IC design without circuit-level or switch-level simulation. This methodology is shown to be practical for VLSI …

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Boolean Reasoning And Informed Search In The Minimization Of Logic Circuits, James J. Kainec Mar 1992

Boolean Reasoning And Informed Search In The Minimization Of Logic Circuits, James J. Kainec

Theses and Dissertations

The minimization of logic circuits has been an important area of research for more than a half century. The approaches taken in this field, however, have for the most part been ad hoc. Boolean techniques have been employed to manipulate formulas, but not to perform symbolic reasoning. Boolean equations are employed principally as icons; they are never solved. The first objective of this dissertation is to apply Boolean reasoning systematically and uniformly to the minimization problem. Boolean reasoning entails the reduction of systems of Boolean equations to a single equation; the single equation is an abstraction, independent of the form …

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Causal Univariate Spatial-Temporal Autoregressive Moving Averages (Starma) Modelling Of Target Information To Generate Tasking Of A World-Wide Sensor System, Kelly A. Greene Mar 1992

Causal Univariate Spatial-Temporal Autoregressive Moving Averages (Starma) Modelling Of Target Information To Generate Tasking Of A World-Wide Sensor System, Kelly A. Greene

Theses and Dissertations

The Department of Defense employs a resource limited world-wide sensor system to detect certain events of interest. The purpose of this research was to establish a methodology using a univariate causal STARMA model for forecasting the relative probability of an event occurring in a geographical location during a time block of the day. These relative probabilities are used as input for a tasking model that assigns the scarce sensor resources so as to optimize the detection of these events. The STARMA model is appropriate for forecasting the relative probabilities because a definite temporal relationship and a definite spatial relationship exists …

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Development Of A Flight Information System Using The Structured Method, Yeong-Lae Kwak Mar 1992

Development Of A Flight Information System Using The Structured Method, Yeong-Lae Kwak

Theses and Dissertations

This thesis documents the development of a database system for the Flight Information System (FIS) of the Korean Air Force. The scope of the FIS is too large to be covered by this thesis. Thus, this thesis covers only the core part of the FIS due to the limitation of time and man-power. This thesis uses the structured method. Structured analysis and structured design techniques are mainly used two techniques. This thesis focused not only the development of the FIS but also the application of the software development method, the structured method, and its tools such as DFD, DD, ERD, …

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Satool Ii: An IdefO Case Workbench Using Ada And The X Window System, Betty Topp Mar 1992

Satool Ii: An IdefO Case Workbench Using Ada And The X Window System, Betty Topp

Theses and Dissertations

The objective of this research effort is to perform an object oriented analysis, design and implementation of the graphical user interface (GUI) for the SATool II system. SATool II is a computer Assisted Software Engineering (CASE) workbench developed using Ada and the X Window system. It is designed to serve as an IDEFo graphical project editor and data dictionary editor. IDEF0 is the ICAM Definition Method Zero graphical notation language adopted by the Air Force to produce a function model of a manufacturing system or environment. The Air Force Institute of Technology is conducting on-going research in the use …

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