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Full-Text Articles in Engineering

A Generic Template Extractor (Gentex) In C For Vlsi Design Verification, Kenneth J. Mcclellan Jr. Dec 1992

A Generic Template Extractor (Gentex) In C For Vlsi Design Verification, Kenneth J. Mcclellan Jr.

Theses and Dissertations

The problem of VLSI design verification through circuit extraction was analyzed. The problems of creating a simple template format, the permutability of pins, maintaining connectivity, and performance were focused on. A generic template extractor (GENTEX) was developed in the C programming language for use as a testbed to find solutions to these problems. Six different extraction algorithms were tested with GENTEX and compared based on performance. EDIF translation programs were used to interface with GENTEX on both the input and output sides. One translation program converted an EDIF representation of a schematic into the template format used by GENTEX. The …

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Radar Cross Section Models For Limited Aspect Angle Windows, Mark C. Robinson Dec 1992

Radar Cross Section Models For Limited Aspect Angle Windows, Mark C. Robinson

Theses and Dissertations

This thesis presents a method for building Radar Cross Section (RCS) models of aircraft based on static data taken from limited aspect angle windows. These models statistically characterize static RCS. This is done to show that a limited number of samples can be used to effectively characterize static aircraft RCS. The optimum models are determined by performing both a Kolmogorov and a Chi-Square goodness-of-fit test comparing the static RCS data with a variety of probability density functions (pdf) that are known to be effective at approximating the static RCS of aircraft. The optimum parameter estimator is also determined by the …

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Real Image Visual Display System, James R. Brandt Dec 1992

Real Image Visual Display System, James R. Brandt

Theses and Dissertations

This thesis investigates a technique for improving the perception of three-dimensionality in images generated by a Silicon Graphics workstation. The technique involves using a spherical mirror into which the graphics from the CRT are projected. A real image of the graphic is formed by the mirror and it appears to be floating at the image plane. The three-dimensional effect is improved by adding reflections or shadows of the displayed object. Additionally, a method of using real objects with computer generated shadows and computer generated objects with real shadows is investigated. This is done in an effort to quantify how far …

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The Effect Of Oxide Layers And Boron Doping On The Breakdown Of High Purity Silicon, Brian A. Hibbeln Dec 1992

The Effect Of Oxide Layers And Boron Doping On The Breakdown Of High Purity Silicon, Brian A. Hibbeln

Theses and Dissertations

For many applications such as lasers and radar drive circuits, there exists a need for solid state high voltage, high current switches. Current gaseous discharge switches fail to satisfy the ruggedness, reliability, and lifetime requirements of today's systems. A promising alternative is the Photoconductive Semiconductor Switch (PCSS). The limiting factor in the operation of these switches is the occurrence of breakdown through channels formed slightly below the surface. A theory on the formation of these channels is presented based upon band bending at the metal-semiconductor interface, a nonhomogeneous space charge due to irregular trap distributions, and thermal runaway in localized …

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Total Hemispherical Emittance Of Niobium-1% Zirconium Fuel Cladding For The Sp-100 Space Reactor, John E. Thomason Iii Dec 1992

Total Hemispherical Emittance Of Niobium-1% Zirconium Fuel Cladding For The Sp-100 Space Reactor, John E. Thomason Iii

Theses and Dissertations

Total hemispherical emittance was measured for the SP-100 reactor fuel cladding alloy (Nb-l% Zr). Based on a standard test method (ASTM C 835-82), experiments were conducted on a reference sample of oxidized stainless steel and then on a sample of actual cladding. The sample is heated in a vacuum by passing DC current through it until reaching equilibrium. Measurements are made of the electrical power dissipated in the sample and of the surface temperature. Using the Stefan-Boltzmann Law and some key assumptions concerning conductive and radiative heat transfer, the measured quantities are used to calculate emittance. Calculated values for unoxidized …

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Spectral And Spatial Pattern Recognition In Digital Memory, John M. Amrine Dec 1992

Spectral And Spatial Pattern Recognition In Digital Memory, John M. Amrine

Theses and Dissertations

The main purpose of this research is to develop a model that can be used to solve combined spectral and spatial pattern recognition problems. The basis of my model is a multiobjective discrete programming model developed by Benabdullah and Wright (B and W). The model will be modified and then tested by solving a real world problem with SPOT multispectral imagery. Several improvements were added to the B and W model, namely standard border length accounting and control over which pixels are selected by the model. The model was also improved to process more than one channel of imagery at …

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Correlation Based Target Location And Identification, Richard A. Wenzel Dec 1992

Correlation Based Target Location And Identification, Richard A. Wenzel

Theses and Dissertations

Correlation was investigated as a technique for locating and identifying visible light terrain board images of tanks, airplanes, and trucks. A correlator was built which utilizes the Fast Fourier Transform. The 180 images in the image set were correlated in both the raw form and after pre-processing via energy normalization and local energy normalization. The correlation of the raw images led to development of quantitative and heuristic rules for possible inclusion in a rule based expert system. The correlation of the local energy normalized images resulted in a 100 percent target location rate and can be used as a baseline …

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Locating An Imaging Radar In Canada For Identifying Spaceborne Objects, William G. Schick Dec 1992

Locating An Imaging Radar In Canada For Identifying Spaceborne Objects, William G. Schick

Theses and Dissertations

This research presents a study of the maximal coverage p-median facility location problem as applied to the location of an imaging radar in Canada for imaging spaceborne objects. The classical mathematical formulation of the maximal coverage p-median problem is converted into network-flow with side constraint formulations that are developed using a scaled down version of the imaging radar location problem. Two types of network-flow with side constraint formulations are developed: a network using side constraints that simulates the gains in a generalized network; and a network resembling a multi-commodity flow problem that uses side constraints to force flow along identical …

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The Adaptation Of The Sei's Capability Maturity Model To The Air Force Software Acquisition Management Process, William G. Dickerhoff Jr., William J. Sommers Dec 1992

The Adaptation Of The Sei's Capability Maturity Model To The Air Force Software Acquisition Management Process, William G. Dickerhoff Jr., William J. Sommers

Theses and Dissertations

This study develops an Air Force Software Acquisition Maturity Framework (SAMF) by adapting the Software Engineering Institute's (SEI) capability Maturity Model (CMM) to the Air Force software acquisition process. The SAMFs purpose is to provide the Air Force Materiel Command's product centers and program off ices with criterion to assess their software acquisition maturity in a similar fashion as the SEI's CMM provides companies a benchmark to measure their organization's software production maturity. The research was accomplished through a combination of information gathering techniques and data analysis. A literature search of documentation, both within and external to the Department of …

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Analysis Of Kriging Applied To Resolution Enhancement Of Digital Satellite Imagery, David J. Blaufuss Dec 1992

Analysis Of Kriging Applied To Resolution Enhancement Of Digital Satellite Imagery, David J. Blaufuss

Theses and Dissertations

To aid the viewer in interpreting the information contained in an image, spatial resolution of the image can be increased. One way to increase the resolution is to improve the optics and sensors of the imaging system. Another is to process the data on the ground by computer. Enhancement techniques can be employed to alter the image and extract necessary data. Current techniques to manipulate and enlarge an image are nearest-neighbor, bilinear interpolation, and cubic convolution which can give greater clarity and readability. To satisfy the growing demand for quality (high-resolution) remotely sensed images, new techniques to enhance images need …

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The Efficacy Of Group Decision Support Systems: A Field Experiment To Evaluate Impacts On Air Force Decision Makers, Benjamin C. Huff Dec 1992

The Efficacy Of Group Decision Support Systems: A Field Experiment To Evaluate Impacts On Air Force Decision Makers, Benjamin C. Huff

Theses and Dissertations

The research contributed to the study of Group Decision Support Systems (GDSS) in field experiments involving real managers making real decisions. This research was conducted by the Air Force Institute of Technology with the Air Force Armstrong Laboratory to evaluate the efficacy of using GDSS technology in an Air Force decision making environment. This study compared facilitated GDSS, facilitated manual, and unfacilitated manual decision making processes. This study focused on performance and secondary outcomes resulting from GDSS effects versus process structure effects. The research evaluated two performance outcomes: GDSS efficiency in terms of decision speed and effectiveness in terms of …

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Shock Tube Study Of The Effects Of Large Density Differences And Blowing Ratio On Heat Transfer To A Film-Cooled Flat Plate, Thomas A. Eads Nov 1992

Shock Tube Study Of The Effects Of Large Density Differences And Blowing Ratio On Heat Transfer To A Film-Cooled Flat Plate, Thomas A. Eads

Theses and Dissertations

The effects of coolant-to-mainstream density ratio (D.R.) and mass flux (blowing) ratio (Mb) on flat plate heat transfer were investigated in a shock tube. The round-nosed plate has a single row of holes inclined 35° downstream with two-diameter lateral spacing and hole length of three diameters. Mixing helium with air in the shock tube produced a D.R. range of 1.2 to 2.1. The parameters studied approach those of film-cooled turbine components. For an Mb range of 0.4 to 3 and 10% mainstream turbulence, heat flux was measured with thin-film heat flux gauges located 4 to 30 hole diameters downstream of …

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A Model For Determining Modular Heat Recovery Incinerator Feasibility On Air Force Installations, Arthur H. Anderson Jr., Paul R. Munnell Sep 1992

A Model For Determining Modular Heat Recovery Incinerator Feasibility On Air Force Installations, Arthur H. Anderson Jr., Paul R. Munnell

Theses and Dissertations

This study constructed a model to determine the feasibility of building municipal solid waste (MSW) fired modular heat recovery incinerators (HRIs) on Air Force installations. The model consisted of three gates. Gate one identified current federal regulatory air emission requirements for various HRI pollutants. It also specified two air pollution control configurations with emission reduction efficiencies capable of achieving these requirements. Gate two presented a life-cycle cost (LCC) economic analysis methodology. Operational and cost data for existing modular HRIs located in the United States facilitated the development of regression equations that estimate capital and annual operating costs for a modular …

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A Comparison Of Computer And Paper Media In Psychological Testing, Anthony C. Hensley, Timothy R. Morris Sep 1992

A Comparison Of Computer And Paper Media In Psychological Testing, Anthony C. Hensley, Timothy R. Morris

Theses and Dissertations

This study examined differences based on computer and paper modes of administration in psychological testing. The hypotheses tested were the expectations that scores on the computer Wonderlic Personnel Test (WPT) would be higher than the paper version and subjects would report higher levels on the computer Vocational Preference Inventory (VPI) scales. A counterbalance experimental design with two experimental groups was used. The subjects were volunteers from the Air Force Institute of Technology (AFIT) and Wright State University (WSU); 90 subjects completed the study. This included 75 students from AFIT and 15 from WSU; 69 subjects were male and 21 were …

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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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A Technical And Practical Study Of Composting As A Solid Waste Management Alternative For The Air Force, Donald R. Abrams, Timothy D. Brecheen Sep 1992

A Technical And Practical Study Of Composting As A Solid Waste Management Alternative For The Air Force, Donald R. Abrams, Timothy D. Brecheen

Theses and Dissertations

This thesis reviews composting as a solid waste management option for the Air Force. The Air Force's Pollution Prevention Program Mandates composting as an opportunity to reduce landfill disposal and save future environmental costs. This research considers composting technologies used in mixed municipal solid waste and yard waste applications. The thesis presents technical aspects of composting and also summarizes operational techniques of successful composting sites across the United States. Composting is a biological process for converting organic waste into a stable product for use as a soil amendment or mulch. The Air Force should immediately begin yard waste composting programs …

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Analysis Of Standard Type Unit Development, Jeffrey M. Hess, Merry D. Wermund Sep 1992

Analysis Of Standard Type Unit Development, Jeffrey M. Hess, Merry D. Wermund

Theses and Dissertations

This research study examined the standard type unit development process for the Air Force. Current standard type unit development procedures were determined by a literature review. The literature review, with the interviews, provided information regarding the history of, purpose for, and possible alternatives for developing standard type units. A Delphi questionnaire was developed to determine how well the current process works, how standard type units worked for Desert Shield/Storm, and possible ways to improve the development process. This questionnaire was distributed to F-15 units, F-16 units, and major command personnel in Tactical Air Command (now Air Combat Command). All three …

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Development Of A Heuristic Knowledge Base For The Selection Of Applicable Or Relevant And Appropriate Environmental Requirements, Scott J. Borg, Gerald B. Puetz Sep 1992

Development Of A Heuristic Knowledge Base For The Selection Of Applicable Or Relevant And Appropriate Environmental Requirements, Scott J. Borg, Gerald B. Puetz

Theses and Dissertations

Applicable or Relevant and Appropriate Requirements (ARARs) are the basis used in establishing threshold limits for hazardous waste cleanups performed under the Comprehensive Environmental Response, Compensation and Liability Act (CERCIA). ARARs selections must be applied consistently at numerous cleanup locations concurrently. The purpose of this research was to analyze activities required for the development of a heuristic knowledge base used for selection of The problem domain for the research was limited CERCLA cleanups of contaminated groundwater, through the use of a pump and treat strategy, using air stripping as the as the cleanup technology. The research examined literature concerning the …

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An Assessment Of The Options Available To Air Forces' Commanders To Suppress Smoke From Oil Well Fires, William B. Owens, Richard D. Taylor Sep 1992

An Assessment Of The Options Available To Air Forces' Commanders To Suppress Smoke From Oil Well Fires, William B. Owens, Richard D. Taylor

Theses and Dissertations

The particulates in smoke from oil well fires can obscure targets and inhibit the use of precision-guided munitions. The purpose of this research was to develop a decision support matrix to aid commanders of air forces select methodologies for controlling oil well fire smoke through fire suppression. Through interviews with military experts and fire-fighters, a set of situational factors affecting the employment of these technologies was developed. Technologies for extinguishing oil well fires were investigated by conducting expert interviews and studying research data, periodical literature, and proposals suggesting means to control the Kuwaiti oil well fires. Over 200 proposals from …

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Issues Affecting Acquisition Strategies For Remedial Action Projects At Installation Restoration Program Sites, John E. Keoshian, William A. Kolakowski Sep 1992

Issues Affecting Acquisition Strategies For Remedial Action Projects At Installation Restoration Program Sites, John E. Keoshian, William A. Kolakowski

Theses and Dissertations

Most, if not all, of Air Force IRP restoration work is accomplished through contracting avenues. The present system of cleanup and close out of these IRP sites is inefficient, time consuming, and costly. Expedient cleanup of contaminated sites will depend in large part upon on how effectively the USAF manages its restoration contracts. Difficulties are encountered due to differences in interpretation and/or vagueness of contracting and environmental information by all parties involved. Additionally, numerous conflicts arise when different agencies apply different acquisition strategies to similar remedial actions. To compound the problem, there are few definitions and little guidance from the …

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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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An Analysis Of The Air Force Enlisted Performance Feedback System, Dee J. Jackson, Mark A. Ward Sep 1992

An Analysis Of The Air Force Enlisted Performance Feedback System, Dee J. Jackson, Mark A. Ward

Theses and Dissertations

This research evaluated the effectiveness of the enlisted evaluation performance feedback system. The Air Force created the feedback system because many airmen, especially those in lower ranks, did not know or did not understand their duties. Therefore, for the purpose of this study, effectiveness was defined as the degree to which the Air Force model mimicked the ideal feedback model as formulated by the researcher's analysis of the literature. The researchers found evidence that the new Air Force feedback system is an improvement over the old design. Under the old system, the only regulated means of providing feedback was a …

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An Investigation Of The Influence Of Advanced Aircraft Diagnostics On The Technological Sophistication Of Maintenance Personnel, Chris R. Collins, Clete W. Knaub Sep 1992

An Investigation Of The Influence Of Advanced Aircraft Diagnostics On The Technological Sophistication Of Maintenance Personnel, Chris R. Collins, Clete W. Knaub

Theses and Dissertations

The purpose of this research was to determine what effect automated diagnostic systems will have on the maintenance worker's technological capabilities. Four investigative questions guided the project: 1. What effect has automation of skilled jobs had on workers in the civilian community?; 2. What technological and psychological traits have led to success in past military conflicts?; 3. What types of technological and psychological traits will technicians have who are heavily dependent on diagnostic systems? (For example, to what degree will maintenance technicians be able to improvise when deployed to a combat area?); and, 4. What lessons can Air Force maintenance …

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Demonstrating The Effects Of Shop Flow Process Variability On The Air Force Depot Level Reparable Item Pipeline, Marvin A. Arostegui Jr., Jon A. Larvick Sep 1992

Demonstrating The Effects Of Shop Flow Process Variability On The Air Force Depot Level Reparable Item Pipeline, Marvin A. Arostegui Jr., Jon A. Larvick

Theses and Dissertations

This study investigated the effects of reducing the mean processing time and variability in the Shop Flow Segment of the Depot Level Reparable Item pipeline. The measure of interest was the average number of units in the pipeline of a particular type of item (referred to as the average pipeline contents). A literature review revealed that process variability in the pipeline has an impact on its effective operation and cost. A simulation model was developed to determine if reducing mean processing time and/or variability in the Shop Flow Segment would result in a reduction in the average pipeline contents. The …

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A Methodology For Model Comparison Using The Theater Simulation Of Airbase Resources And All Mobile Tactical Air Force Models, Heston R. Hicks, Lawrence L. Long Sep 1992

A Methodology For Model Comparison Using The Theater Simulation Of Airbase Resources And All Mobile Tactical Air Force Models, Heston R. Hicks, Lawrence L. Long

Theses and Dissertations

This research compares the Theater Simulation of Airbase Resources (TSAR) model to the sortie generation (SORGEN) module of the AH Mobile Tactical Air Force (AMTAF) model, qualitatively and quantitatively, while concurrently developing and proving a model co methodology. The qualitative analysis compares the models' background and documentation, features and databases, and useability. The quantitative analysis statistically compares the models' estimates of sorties generated. For the quantitative study, eight variables are chosen and assigned high and low values for use in a 2' 1/4 fractional factorial experimental design. Equivalent input databases are developed from a TSAR F-15C database and pilot trials …

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Cultural Resources Management In The United States Air Force: Development Of A Planning Primer, Steven R. Becker, Russell R. Hula Sep 1992

Cultural Resources Management In The United States Air Force: Development Of A Planning Primer, Steven R. Becker, Russell R. Hula

Theses and Dissertations

The purpose of this study was to produce a USAF base-level primer for use as a guide to requirements, standards, and procedures concerning the preservation of cultural resources. Cultural resources include buildings, sites, districts, structures, and objects that have significant scientific, historic, or cultural value. The research had two major objectives: (1) Identify existing sources of cultural resource information through a review of legal requirements, regulations, USAF policy documents, and other sources such as data bases. (2) Produce a 'cultural resources management primer' after identifying the appropriate characteristics of a primer. This product could then be used by novice personnel …

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A Model-Based Methodology For Evaluating The Unit-Level Air Combat Mission Planning (Acmp) Process, Thomas L. Gaylord, George L. Sowell Sep 1992

A Model-Based Methodology For Evaluating The Unit-Level Air Combat Mission Planning (Acmp) Process, Thomas L. Gaylord, George L. Sowell

Theses and Dissertations

This study modeled the USAF unit-level Air Combat Mission Planning (ACMP) process and developed a methodology for evaluating the effectiveness of changes to the process. The study also reports relevant mission planning lessons learned from Desert Storm and demonstrates application of the developed evaluation methodology. An exploratory multidisciplinary literature review builds a research foundation for the evaluation methodology. Foundation areas reviewed include unit-level operations, command and control, planning, decision theory, decision aiding, and model-based problem solving. The conceptual model of the planning process defines sixteen functions starting from receipt of tasking and concluding with execution departure. For each of the …

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Cost/Schedule Control Systems Criteria: A Reference Guide To C/Scsc Information, Erik G. Cummings, Kirk A. Schneider Sep 1992

Cost/Schedule Control Systems Criteria: A Reference Guide To C/Scsc Information, Erik G. Cummings, Kirk A. Schneider

Theses and Dissertations

This thesis effort provides a valuable tool for contract performance measurement (CPM) analysts to use both while attending formalized Cost/Schedule Control Systems Criteria (C/SCSC) training, and while on the job. Research indicated a large amount of written material existed on contract performance measurement and the more specific topic of C/SCSC, yet this information was hidden in a wide array of unindexed professional journals, master's thesis, and texts. Further, while many professions have a reference guide of annotated bibliographies, CPM had none. Through an extensive literature review using several search and retrieval methods, the authors were able to amass a bibliography …

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Desert Express: Framework For Institutionalization Of Express Airlift Procedures, Terry D. Basham, Jason G. Evgenides Sep 1992

Desert Express: Framework For Institutionalization Of Express Airlift Procedures, Terry D. Basham, Jason G. Evgenides

Theses and Dissertations

This study was sponsored by the Military Airlift Command to examine the Desert Express airlift channel used during Operation Desert Shield/Desert Storm. The goal was to determine what changes or improvements should be made prior to formalizing Desert Express procedures into Department of Defense doctrine. The research method used was a Literature Review supported by an application of the Delphi Technique. The Literature Review reviewed past military express operations and current regulatory procedures to raise key issues. These issues were then presented to 19 airlift experts in two-separate rounds of written questionnaires. The research revealed that Desert Express was the …

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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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