Engineering Commons^™

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 …

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, …

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 …

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 …

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 …

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 …

Change In Self-Efficacy As A Measure Of Training Effectiveness At Squadron Officer School, Edward J. Berghorn, Michael Lewis

Theses and Dissertations

The purpose of this research was to determine the effect of the US air Force Squadron Officer School (SOS) training curriculum by measuring students' self-efficacy before and after training. The authors verified through the literature that an individual's personal assessment of his self-efficacy was associated with task understanding and performance. Then self-efficacy questions were generated (for each of the four SOS curriculum areas) for an individual to assess his ability to perform a behavior related to a particular SOS learning objective. Demographic questions were also developed and combined with the self- efficacy questions to form pretest (before SOS training) and …

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 …

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 …

Range Scheduling Automation For The Air Force Satellite Control Network: A Case Study In Computer System Development, Donald J. Aitken, Steven C. Bishop

Theses and Dissertations

This study explored the factors influencing divergent outcomes of two computer system development efforts which were undertaken to fulfill the same requirement for computer automation of a manual resource scheduling process. The first project employed the traditional waterfall approach to system development, but resulted in user rejection and cancellation after considerable resources and effort had been expended. The second project employed prototyping and both the process and the product were well received by the users and ultimately produced an operational system. Analysis yielded eight contributory factors to the failure of the first effort. Three of these were related to the …

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 …

An Assessment Of Afit Sys200, 'Acquisition Planning And Analysis', As A Broadening Course Under Apdp, Daryl J. Hauck, Charles A. Manship

Theses and Dissertations

This study assessed AFIT's SYS200 course, 'Acquisition Planning and Analysis,' to determine whether it serves adequately as a broadening course under the Acquisition Professional Development Program (APDP). APDP certification requires persons in eight acquisition functional disciplines (Acquisition Logistics, Systems R and D/ Engineering, Program Management, etc.) to complete SYS200. Three complementary measures (assessing knowledge, self- efficacy, and a supervisor assessment) were used to determine whether SYS200 conveyed its curriculum effectively to members of all functional disciplines. The results showed that SYS200 attendance produced substantial increases in acquisition-related knowledge, self-efficacy, and supervisor assessments for all functional disciplines. In all three measures, …

Pollution Prevention, An Investment Decision Model To Assess Financial Feasibility For Application To Air Force Processes, Debra S. Rankin, Clare R. Mendelsohn

Theses and Dissertations

This research develops a Pollution Prevention Investment Decision Model (PPIDM) to evaluate the financial feasibility of pollution prevention alternatives. The PPIDM provides managers with simple, systematic, and flexible guidelines for making accurate and expedient decisions when considering pollution prevention alternatives. The model illustrates that a comprehensive analysis is not always necessary. The PPIDM gives managers the flexibility to adjust the economic feasibility criteria based on top management's perceptions of the political environment. When top management places a very high value on political considerations, economic criteria is insignificant and the project may be implemented immediately without further analysis. The PPIDM takes …

A Methodology For Project Selection Using Economic Analysis And The Analytic Hierarchy Process, Jeffrey L. Battin, Thomas J. Bender

Theses and Dissertations

This study examined the applicability of a multiple criterion decision making method, known as the Analytic Hierarchy Process (AHP) , to economic analysis decisions involving project selection. Through a survey of the literature and current practices, it was determined that qualitative criteria were not adequately represented in a typical economic analysis of projects. Several MCDM methods were examined and the AHP was found to be the most promising technique to rate projects on a ratio scale. Two types of project selection problems, those involving nonmutually exclusive alternatives and those involving mutually exclusive alternatives, were examined. It was determined that the …

An Investigation Of Integrated Weapon System Management Implementation Issues, Scott A. Dalrymple, Lester F. Pietraszuk

Theses and Dissertations

This thesis investigated Integrated Weapon System Management implementation issues. Five functional areas were examined: Contracting, Engineering, Financial management, Program Management, and Test Management. Data was collected through interviews. The most significant lessons learned were to establish a direct chain of command and to use TQM principles. Program business practices were changed by increasing Product Center/ALC interaction and implementing a single joint CCB. Program personnel obtained useful guidance from other IWSM programs and from the information products distributed by HQ AFMC. Communication improvements included increased teleconference capability and establishment of a Local Area Network. Cultural differences between centers, insufficient initial guidance, …

Development And Application Of A Methodology For Evaluating Type Ii Expired Shelf Life Hazardous Material Generation In The United States Air Force, Jennifer Putz

Theses and Dissertations

The Pollution Prevention Act of 1990, Air Force Directive 19-4, and the Air Force Pollution Prevention Plan require installations to reduce the amounts of hazardous waste generated. To meet the requirements set forth in these documents, each waste stream containing a hazardous waste needs to be identified and characterized for changes in policies or procedures that would reduce the hazardous waste generated. This research develops a methodology to determine the amount of materials with a type II shelf life that is disposed of as hazardous waste because the shelf life expired while the material was in base supply storage. This …

A Study Of Configuration Management At Headquarters Logistics Command (Royal Australian Air Force), John F. Turner

Theses and Dissertations

The purpose of this research was to provide insight into configuration management at the Royal Australian Air Force's Headquarters Logistics Command (HQLC) by determining whether current configuration management practices have any impact on HQLC's ability to meet its mission of providing logistics support. The research begins with a review of RAAF configuration management policy and procedures as applicable to in-service systems or technical equipment. A case study is used to investigate problems associated with inadequate configuration management being experienced by one HQLC engineering section, and to identify subsequent effects on engineering logistics capability. The case study results are used to …

Estimating The Operating And Support Cost Difference Between Royal Australian Air Force C-130e And C-130h Hercules Aircraft, Terrence J. Sidey

Theses and Dissertations

This research investigated the operating and support cost (O & S cost) of Royal Australian Air Force (RAAF) C-130E and C-130H aircraft. The purpose was twofold: to provide information about the relative O & S cost of the RAAF's old and "new" C-130 aircraft; and to increase knowledge and understanding of aircraft O & S costing within the RAAF. Preliminary research indicated that RAAF O & S costing was rudimentary and that suitable O & S data would be difficult to obtain. Accordingly, an analogous O & S cost system -- the U.S. Air Force (USAF) SABLE cost model and …

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 …

The Detection And Correlation Modeling Of Rayleigh Distributed Radar Signals, Alan L. Buterbaugh

Theses and Dissertations

This thesis provides a method for determining the detection of partially correlated Rayleigh distributed radar returns by a pulsed search radar. The receiver consists of a quadrature demodulator receiver, followed by a square law envelope detector and a linear post-detection integrator. In addition, a technique for determining the pulse-to-pulse correlation of a complex target is given using inverse Fourier transforms of the target scattering centers. An AIM-9 missile is used to illustrate how the partially correlated detection techniques and the pulse-to-pulse correlation predictions can be used to determine the probability of detection. The Detection and Correlation Modeling of Rayleigh Distributed …

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 …

Co-Channel Speaker Separation, Thomas S. Andrews

Theses and Dissertations

In the co-channel speaker separation problem, the goal is to recover two separate speech signals from a monaural channel which contains the sum of the two speech signals. A new methodology is developed that if given that a segment of co-channel speech is separated into a stronger and weaker segment, the correct assignment of these separated segments to the appropriate talker can be made using a Linear Predictive Coding (LPC) based minimum-prediction residual computation. The uniqueness of the developed technique is that no a priori information is required of the co-channel speech signal. The information needed to appropriately assign these …

Speech Recognition Using Visible And Infrared Detectors, Patrick T. Marshall

Theses and Dissertations

A system has been developed that tracks lip motion using infrared (IR) or visible detectors. The purpose of this study was to determine if the additional information obtained from the IR or visible detectors can be used to increase the recognition rate of audio Automatic Speech Recognition (ASR) systems. To accomplish this goal, several hardware analog prototypes had to be designed, built and tested. Different detectors (IR and visible) and modes of operation (active and passive) were tried before a reliable and useful signal was found. An analog-to-digital (A/D) board was then designed and built that digitized both the microphone …

Modification, Reimplementation And Studies Using The Meisner Model Of The Heart, Ari Zvi Zivotofsky

Theses

The study of left ventricular filling in both the normal and the pathological heart is of great importance. A computer model simulation of the heart with emphasis on mitral flow was designed by Meisner in 1986 and implemented in QuickBASIC. This paper discusses how the original program was altered to be able to perform "Parameter vs. Parameter" runs in which it can be observed how varying an input parameter affects output parameters. The output data is then formatted in such a way that it can be used by QUATTRO PRO, a standard spreadsheet package, to yield graphical outputs.

In addition, …

Minimization Of Exclusive Sum Of Products Expressions For Multiple-Valued Input Incompletely Specified Functions, Ning Song

Dissertations and Theses

In recent years, there is an increased interest in the design of logic circuits which use EXOR gates. Particular interest is in the minimization of arbitrary Exclusive Sums Of Products (ESOPs). Functions realized by such circuits can have fewer gates, fewer connections, and take up less area in VLSI and especially, FPGA realizations. They are also easily testable. So far, the ESOPs are not as popular as their Sum of Products (SOP) counterparts. One of the main reasons it that the problem of the minimization of ESOP circuits was traditionally an extremely difficult one. Since exact solutions can be practically …

Thermal Post-Buckling And Vibration Analysis Of Thermally Buckled Antisymmetrically Laminated Beams Using A 20 Dof Finite Element, Misao Mizuno

Master's Theses - Daytona Beach

The purpose of this study is to use the finite element method to analyze thermal buckling, post-buckling, and vibrations of thermally buckled composite beams including shear deformation. The beam element used has ten degrees of freedom at each node: axial displacement, transverse displacement due to bending and shear, twisting angle, inplane shear rotation and their derivatives with respect to x. Hermitian polynomials and Lagrange's equation were used to derive the equations of motion. The equations of motion were divided into static and dynamic parts. For buckling analysis, the eigenvalue problem was solved for the critical temperature. The scaled first mode …

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 …

A Novel Technique For Deep Level Characterization Of High-Resistivity Semiconductor Materials, Sridhar Panigrahi

Electrical & Computer Engineering Theses & Dissertations

An improved photo induced current transient spectroscopy (PICTS) technique is developed for studying deep level parameters in high-resistivity semiconductor materials. A new digital data acquisition approach and improvement in the cryogenics of the system have enabled us, for the first time in our laboratory, to detect CuA level in a copper doped silicon compensated gallium arsenide (GaAs:Si:Cu) sample. The digital approach improves both the signal to noise ratio (S/N) and the efficiency of the system. Also, multiple PICTS spectra in a single thermal cycle can be obtained. In the present work, various doped and undoped gallium arsenide ( GaAs) and …

Experimental Investigation Of Crossflow Instability Waves In Rotating Disk Flow, Alan E. Blanchard

Mechanical & Aerospace Engineering Theses & Dissertations

For the past 40 years, the crossflow (or inflectional) instability associated with rotating disk flow has been generally assumed to be a pure vortex that is fixed with respect to the disk; however, the terms "wave" and "vortex" have also been used interchangeably throughout the computational and experimental literature to describe this instability. Through the use of both hot-wire surveys and smoke-wire flow visualizations in the present investigation, the existence of crossflow instability waves prior to vortex formation has been shown. The results of the hot-wire surveys and smoke-wire flow visualizations for both a "clean" disk case and a disk …

Analysis Of Impact Damage Of Composite Laminates Using Five-Point Bending, Mark Edward Robeson

Mechanical & Aerospace Engineering Theses & Dissertations

The low-velocity impact of composite laminates can induce high transverse shear strains, resulting in severe damage within the laminate. This type of damage may be studied in a quasi-static manner by use of a multi-span beam shear test in five-point bending configuration. A five-point bending arrangement induces high transverse shear strains in sections of the laminate, causing failures, such as intraply cracks and delaminations, that are similar to those caused by low-velocity impact. Stress distributions in the laminate can be calculated using a potential energy approach, and these stress distributions can be correlated with failure locations in the five-point bending …