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An Integrated Gps-Ins-Baro And Radar Altimeter System For Aircraft Precision Approach Landings, Robert A. Gray Dec 1994

An Integrated Gps-Ins-Baro And Radar Altimeter System For Aircraft Precision Approach Landings, Robert A. Gray

Theses and Dissertations

Currently, the Department of Defense (DoD) and the commercial airline industry are utilizing the Instrument Landing System (ILS) during aircraft landings for precision approaches. The replacement system for the aging ILS was thought to he the Microwave Landing System (MLS). Instead, use of the Global Positioning System (GPS) is now thought to be a viable replacement for ILS precision approaches. The majority of current precision landing research has exploited 'stand-alone' GPS receiver techniques. This thesis instead explores the possibilities of using an extended Kalman filter (EKF) that integrates an Inertial Navigation System (INS), GPS, Barometric Altimeter, Pseudolite and Radar Altimeter …


Multiclassifier Fusion Of An Ultrasonic Lip Reader In Automatic Speech Recognition, David L. Jennnings Dec 1994

Multiclassifier Fusion Of An Ultrasonic Lip Reader In Automatic Speech Recognition, David L. Jennnings

Theses and Dissertations

This thesis investigates the use of two active ultrasonic devices in collecting lip information for performing and enhancing automatic speech recognition. The two devices explored are called the 'Ultrasonic Mike' and the 'Lip Lock Loop.' The devices are tested in a speaker dependent isolated word recognition task with a vocabulary consisting of the spoken digits from zero to nine. Two automatic lip readers are designed and tested based on the output of the ultrasonic devices. The automatic lip readers use template matching and dynamic time warping to determine the best candidate for a given test utterance. The automatic lip readers …


A Systems Engineering Approach To Environmental Risk Management: A Case Study Of Depleted Uranium At Test Area C-64, Eglin Air Force Base, Florida, Charles M. Carter, Kristina M. Fortmann, Stephen W. Hill, Robert M. Latin, Edward J. Masterson, Joseph A. Roh, Sujay R. Setlur Dec 1994

A Systems Engineering Approach To Environmental Risk Management: A Case Study Of Depleted Uranium At Test Area C-64, Eglin Air Force Base, Florida, Charles M. Carter, Kristina M. Fortmann, Stephen W. Hill, Robert M. Latin, Edward J. Masterson, Joseph A. Roh, Sujay R. Setlur

Theses and Dissertations

Environmental restoration is an area of concern in an environmentally conscious world. Much effort is required to clean up the environment and promote environmentally sound methods for managing current land use. In light of the public consciousness with the latter topic, the United States Air Force must also take an active role in addressing these environmental issues with respect to current and future USAF base land use. This thesis uses the systems engineering technique to assess human health risks and to evaluate risk management options with respect to depleted uranium contamination in the sampled region of Test Area (TA) C-64 …


A 3-D Finite Difference Time Domain Investigation Of Microwave Propagation Through Inhomogeneous Biological Materials, David B. Dunn Jr. Dec 1994

A 3-D Finite Difference Time Domain Investigation Of Microwave Propagation Through Inhomogeneous Biological Materials, David B. Dunn Jr.

Theses and Dissertations

This paper extends past analysis of an optimal source distribution around a homogeneous sphere of muscle tissue by using a 3-D finite difference time domain (FDTD) scenario in which an anatomically correct human head model is irradiated. It first duplicates the analytical solution within an FDTD space using an FDTD computer code developed at Penn State University. This duplication uses a 9.45 cm radius sphere represented in an FDTD space of 2.35 mm cubic cells. FDTD simulations are then performed on four, three, and two layer laminated spheres, designed to provide simple models of a head. Finally, four simulations were …


An Analysis Of The Kc-135 Three-Person Cockpit, Robert A. Deivert Dec 1994

An Analysis Of The Kc-135 Three-Person Cockpit, Robert A. Deivert

Theses and Dissertations

In an effort to quantitatively determine the utility of mission effectiveness of the KC-135, this research used value-focused thinking to measure the impact of replacing the KC-135 navigator with upgraded avionics. A Value Model was developed as a hierarchy with fundamental objectives at the highest level and attributes at the lowest level. Weights were assigned to show the contribution each level had to the one above it. The attributes were given a score and an additive model was used to determine utility with and without a navigator. Break-even analysis and net present value calculations were done to show the costs …


Generic Satellite Monitoring Expert System, Loretta A. Kelemen Dec 1994

Generic Satellite Monitoring Expert System, Loretta A. Kelemen

Theses and Dissertations

Air Force Satellite Operations is undergoing major changes. Operators no longer receive detailed satellite training, instead they are taught basic fundamentals of satellite operations and expected to control multiple multimillion dollar satellites. The need is clear. An efficient and economical automated system is necessary to assist the satellite operator in his daily tasks of maintaining these DOD priority resources. Satellite intelligent controllers been under R&D since the early 1980s to this need. These systems, however, have focused on the control of one constellation of satellites. In a military striving for efficiency and lower costs, developing a unique intelligent controller for …


Life Cycle Costs Of Alternatives For F-16 Printed Circuit Board Diagnosis Equipment, Kent R. Montgomery, Clifford B. Thorstenson Dec 1994

Life Cycle Costs Of Alternatives For F-16 Printed Circuit Board Diagnosis Equipment, Kent R. Montgomery, Clifford B. Thorstenson

Theses and Dissertations

This study analyzes two alternatives for printed circuit board (PCB) diagnosis for the F-16 depot PCB repair shop from a life cycle cost (LCC) perspective. Alternative 1 assumes the use of the current F-16 automatic test equipment (ATE) while Alternative 2 augments the current ATE with infrared imaging test equipment. Infrared imaging is a developed technology that is currently available to the Air Force in a commercial-off-the-shelf (COTS) form. Using the Cost Analysis and Strategy Assessment (CASA) Life Cycle Cost (LCC) Model and data from the DL41 database on F-16 PCBs this study determined that over the current expected life …


Analysis Of Modal Behavior At Frequency Cross-Over, Robert N. Costa Jr. Nov 1994

Analysis Of Modal Behavior At Frequency Cross-Over, Robert N. Costa Jr.

Theses and Dissertations

The existence of the mode crossing condition is detected and analyzed in the Active Control of Space Structures Model 4 (ACOSS4). The condition is studied for its contribution to the inability of previous algorithms to successfully optimize the structure and converge to a feasible solution. A new algorithm is developed to detect and correct for mode crossings. The existence of the mode crossing condition is verified in ACOSS4 and found not to have appreciably affected the solution. The structure is then successfully optimized using new analytic methods based on modal expansion. An unrelated error in the optimization algorithm previously used …


Optimal Pulsed Pumping For Aquifer Remediation When Contaminant Transport Is Affected By Rate-Limited Sorption: A Calculus Of Variation Approach, Richard T. Hartman Sep 1994

Optimal Pulsed Pumping For Aquifer Remediation When Contaminant Transport Is Affected By Rate-Limited Sorption: A Calculus Of Variation Approach, Richard T. Hartman

Theses and Dissertations

The remediation of groundwater contamination continues to persist as a social and economic problem due to increased governmental regulations and public health concerns. Additionally, the geochemistry of the aquifer and the contaminant transport within the aquifer complicates the remediation process to restore contaminated aquifers to conditions compatible with health-based standards. Currently, the preferred method for aquifer cleanup pump-and-treat has several limitations including, the persistence of sorbed chemicals on soil matrix and the long term operation and maintenance expense. The impetus of this research was to demonstrate that a calculus of variations approach could be applied to a pulsed pumping aquifer …


Design And Analysis Of Constrained Layer Damping Treatments For Bending And Torsion, Kimberly J. Balkema Sep 1994

Design And Analysis Of Constrained Layer Damping Treatments For Bending And Torsion, Kimberly J. Balkema

Theses and Dissertations

In this dissertation, different aspects of constrained layer damping treatments on beams of various geometries are studied. First, the optimal length of a constrained layer damping treatment mounted on a surface in linear strain is identified as a function of the relative stiffnesses of the damping layers and the non-uniformity of the surface stain. The analysis extends previous work that considered the case of uniform surface strain. Sixth order sandwich beam theory is then modified for use with a rectangular beam covered with a segmented constrained layer damping treatment. Non-dimensional variables are used to simplify the form of the problem. …


A Numerical Analysis Of Smoothed Particle Hydrodynamics, David A. Fulk Sep 1994

A Numerical Analysis Of Smoothed Particle Hydrodynamics, David A. Fulk

Theses and Dissertations

This dissertation studies the numerical method of Smoothed Particle Hydrodynamics SPH as a technique for solving systems of conservation equations. The research starts with a detailed consistency analysis of the method. Higher dimensions and non-smooth functions are considered in addition to the smooth one dimensional case. A stability analysis is then performed. Using a linear technique, an instability is found. Solutions are proposed to resolve the instability. Also a total variation stability analysis is performed leading to a monotone form of SPH. The concepts of consistency and stability are then used in a convergence proof. This proof uses lemmas derived …


Application Of A Risk Model To Quantify Relative Risk Of Remedial Actions, Timothy L. Fuller Sep 1994

Application Of A Risk Model To Quantify Relative Risk Of Remedial Actions, Timothy L. Fuller

Theses and Dissertations

To properly manage the Installation Restoration Program (IRP) in the future, Air Force remedial project managers (RPMs) need a metric to assist in the selection of remedial alternatives for the safe and effective clean up of waste contamination sites. If the baseline site risk assessment indicates that it is necessary to remediate a waste contamination site, it is important to the RPM that the selection process for remediation alternatives considers the potential human health and ecological risks associated with the proposed remediation process. In some instances, the risks may be significant when compared to the baseline conditions. The Air Force …


Modeling Trihalomethane Formation Potential From Wastewater Chlorination, Carol A. Mccormick Sep 1994

Modeling Trihalomethane Formation Potential From Wastewater Chlorination, Carol A. Mccormick

Theses and Dissertations

The deletion of federally mandated fecal coliform limits has led many states to review and modify their wastewater disinfection requirements. One issue in analyzing wastewater disinfection is the discharge of potentially carcinogenic halogenated organics formed during the chlorination process. This research investigates the formation of one class of the halogenated organics, the trihalomethanes. The applicability of using drinking water trihalomethane formation models for use with wastewater effluent is examined. Three models are compared for predictive capability by using measured trihalomethane values from previous research data. The results show that a previously developed model is applicable for use based on assumptions …


A Requirements Analysis For An Integrated Maintenance Information System Application Into Theater Air Control System Maintenance, Morris C. Blumenthal Iii, Stephen W. Starks Sep 1994

A Requirements Analysis For An Integrated Maintenance Information System Application Into Theater Air Control System Maintenance, Morris C. Blumenthal Iii, Stephen W. Starks

Theses and Dissertations

This research was to determine to what extent Integrated Maintenance Information System IMIS functional requirements could satisfy the maintenance information requirements of the ground-based Theater Air Control System. IMIS is a program sponsored by Armstrong Laboratory at Wright-Patterson Air Force Base, Ohio to automate maintenance information. To date, Armstrong Laboratory has only targeted aircraft maintenance for this automated program. The Theater Air Control System contains powerful military radars connected to a mobile communications and computer network. Theater Air Control System maintenance information requirements were identified through a study of the 728th Air Control Squadron at Eglin Air Force Base, Florida, …


3d Stereo Data Visualization And Representation, Kai-Heng (Felix) Wang Sep 1994

3d Stereo Data Visualization And Representation, Kai-Heng (Felix) Wang

Theses and Dissertations

This thesis investigates a technique for improving the perception and visualization of three dimensional information. This improvement will eventually give physicians the ability to both visualize and understand biomedical image data. Raw data is used to generate a stereo image pair. The raw data must be put in run length encoding RLE format and then converted to a stereo pair. Once the stereo pair is generated, they must be displayed on the Silicon Graphics ONYX workstation in stereo mode. This research uses 3D images of planets and satellites. The display information is transmitted across cable and is projected onto a …


Simulation Of Hydrologic Influences On Wetland Ecosystem Succession, Robert A. Pompilio Sep 1994

Simulation Of Hydrologic Influences On Wetland Ecosystem Succession, Robert A. Pompilio

Theses and Dissertations

This research focuses on the development of a simulation model to determine the effects of hydrological influences on a wetland ecosystem. The model allows perturbations to the inputs of various wetland data which in turn, influences the successional development of the ecosystem. This research consisted of converting a grassland ecosystem model to one which simulates wetland conditions. The critical factor in determining the success of wetland creation is the hydrology of the system. There are four of the areas of the original model which are affected by the hydrology. The model measures the health or success of the ecosystem through …


Status Of Storm Water Pollution In The United States, Lynne A. Urquhart Sep 1994

Status Of Storm Water Pollution In The United States, Lynne A. Urquhart

Theses and Dissertations

The purpose of this study was to determine the status of storm water pollution in the United States Air Force. This is important since most AF bases are now required to have applied for a NPDES storm water permit. The objectives of the study were to: evaluate the sampling rates used at AF bases; determine the pollutants tested for by the AF bases; compare the pollutant concentrations of the AF bases to an EPA water quality standard; and determine if there were any trends in sampling or pollutant concentrations due to seasonal changes or across AF Commands or EPA Regions. …


Decision Support Model To Compare Hazardous Waste Site Remediation Process Alternatives, Christopher E. Findall Sep 1994

Decision Support Model To Compare Hazardous Waste Site Remediation Process Alternatives, Christopher E. Findall

Theses and Dissertations

This research focuses on the development of a decision support model to identify the preferred methods of site characterization and treatment technology identification using the principles of decision analysis theory. The model provides an effective decision making tool to evaluate and compare the feasibility of using alternative methods of completing the RIFS process. Given a specific site remediation project, the users of this model can enter site- specific cost, duration and likelihood values to determine the expected value for various alternative processes. This thesis postulates that the alternative having the highest expected value is considered the preferred alternative. In calculating …


Standardization Of Protocol For The Sampling, Testing And Abatement Of Asbestos Containing Joint Compound, Gary J. Schneider Sep 1994

Standardization Of Protocol For The Sampling, Testing And Abatement Of Asbestos Containing Joint Compound, Gary J. Schneider

Theses and Dissertations

This study investigated the differing regulatory guidelines from the Occupational Safety and Health Administration and the Environmental Protection Agency concerning the abatement of Asbestos Containing Joint Compound (ACJC). The specific interest was whether or not adequate protection was being afforded demolition workers when exposed to working with ACJC materials that contain less than 1.0 percent asbestos. A spreadsheet was written to estimate the exposure scenario which might be experienced within a given room size on a demolition or renovation jobsite. Spreadsheets were calculated for ACJC with an asbestos content of 0.1 to 0.9 percent in 0.1 increments for rooms ranging …


Solvent Substitution Methodology Using Multiattribute Utility Theory And The Analytical Hierarchical Process, Jaimie S. Tiley Sep 1994

Solvent Substitution Methodology Using Multiattribute Utility Theory And The Analytical Hierarchical Process, Jaimie S. Tiley

Theses and Dissertations

This study developed a multicriteria decision making methodology for the ranking of solvent cleaning process alternatives. This includes development of univariate value functions and criteria and the incorporation or required alternative attributes. It also compares the Analytical Hierarchical Process and Multiattribute Utility Theory in reference to a cleaning substitution process. An actual Air Force cleaning process evaluation problem is considered to verify the research. The test problem ranks several cleaning alternatives for the replacement of a hazardous solvent used in the general cleaning of aircraft engine components.


An Analysis Of The Effect Of Personnel Drawdown Initiatives On Aircrew Experience, Keith L. Hedgepeth, Lennie J. Simpson Sep 1994

An Analysis Of The Effect Of Personnel Drawdown Initiatives On Aircrew Experience, Keith L. Hedgepeth, Lennie J. Simpson

Theses and Dissertations

This study analyzes the effects of personnel reduction initiatives on aircrew experience levels of Air Force pilots and navigators. Four key measures of experience were defined, including total flight hours, flying hours in Primary Assigned Aircraft PAA, total hours at time of upgrade to instructor, and total PAA hours at time of upgrade to instructor. Three objectives were established for this study. These objectives measured the degree of change in overall aircrew experience for pilots and navigators in six major weapon systems, to determine if changes in aircrew experience varied by weapon system, and if changes in aircrew experience varied …


Volatile Organic Compound Emissions From Usaf Wastewater Treatment Plants In Ozone Nonattainment Areas, Brian A. Ouellette Sep 1994

Volatile Organic Compound Emissions From Usaf Wastewater Treatment Plants In Ozone Nonattainment Areas, Brian A. Ouellette

Theses and Dissertations

In accordance with the 1990 Clean Air Act Amendments CAAA, this research conducts an evaluation of the potential emission of volatile organic compounds VOCs from selected Air Force wastewater treatment plants. Using a conservative mass balance analysis and process specific simulation models, volatile organic emission estimates are calculated for four individual facilities--Edwards AFB, Luke AFB, McGuire AFB, and McClellan AFB--which represent a cross section of the current inventory of USAF wastewater plants in ozone nonattainment areas. From these calculations, maximum facility emissions are determined which represent the upper limit for the potential VOC emissions from these wastewater plants. Based on …


Developing An Emission Factor For Hazardous Air Pollutants For An F-16 Using Jp-8 Fuel, Donald J. Van Schaack Sep 1994

Developing An Emission Factor For Hazardous Air Pollutants For An F-16 Using Jp-8 Fuel, Donald J. Van Schaack

Theses and Dissertations

The 1990 Clean Air Act amendments drastically changed the legislation of hazardous air pollutants HAPs or air toxics. Title 3 of the act which specifically addresses HAPs now lists 189 substances which may require regulation as air toxics. Consequently, the reporting of HAP emissions from all Air Force operations will be required in the future. However, the Department of Defense DoD does not have methods available to report this information. This thesis develops emission factors for selected HAPs from an F-16 CD aircraft F110 engine operating on JP-8 fuel. The methodology included determining which HAPs should be selected, using past …


A Quantitative Method For Screening Pollution Prevention Program Options At United States Air Force Installations, Wayne M. Williams Sep 1994

A Quantitative Method For Screening Pollution Prevention Program Options At United States Air Force Installations, Wayne M. Williams

Theses and Dissertations

US Air Force installations worldwide are required to implement pollution prevention (PP) programs designed to reduce the release of pollutants to the environment, and the Air Force uses opportunity assessments (OAs) to identify and evaluate waste producing processes that could benefit from a PP project. The OA process guidance provides extensive details on how to identify potential projects and on how to economically evaluate a project selected for implementation. However, it provides only cursory information about how to decide which projects should be selected for this evaluation. This thesis bridges that gap by providing a quantitative model to be used …


A Preliminary System Dynamics Model Of A Constructed Wetland For The Mitigation Of Metals In Usaf Storm Water, Mark P. Smekrud Sep 1994

A Preliminary System Dynamics Model Of A Constructed Wetland For The Mitigation Of Metals In Usaf Storm Water, Mark P. Smekrud

Theses and Dissertations

This thesis determines the potential removal and corresponding accumulation of trace metals from Air Force storm water in a constructed wetland through the use of a System Dynamics model. The goal is to determine whether constructed wetlands used as storm water best management practices provide efficient metal removal while creating only benign accumulations of such pollutants. Its purpose is to allow Base Civil Engineers and Environmental Managers a better tool to assess the long-term effects of a constructed wetland used as a storm water mitigation technique. The research is limited to the assessment of typical metal concentrations found in Air …


Quality Improvement Analysis Of The Air Force Aircraft Maintenance And Munitions Officers Course, Jeffrey T. Acred, James R. Witter Sep 1994

Quality Improvement Analysis Of The Air Force Aircraft Maintenance And Munitions Officers Course, Jeffrey T. Acred, James R. Witter

Theses and Dissertations

Previous research concerning aircraft maintenance officer training focused on the content of the training curriculum of the Aircraft Maintenance and Munitions Officers Course AMMOC. Conversely, this study sought improvement in aircraft maintenance officer training by evaluating the guidance and support provided to AMMOC. Two methods were employed for identifying such opportunities. First, a descriptive model of the training system supporting AMMOC was developed and analyzed. Second, feedback was solicited from AMMOC instructors through the use of a two-round Delphi. The Delphi was employed to develop a consensus among the instructors regarding what improvement opportunities existed and potential means for taking …


Review Of Factors Impacting Cost Benefit Analysis (Cba) For Implementing Improvements To The Air Force Technical Order System, Susan J. Bergin, Terry A. Parsons Sep 1994

Review Of Factors Impacting Cost Benefit Analysis (Cba) For Implementing Improvements To The Air Force Technical Order System, Susan J. Bergin, Terry A. Parsons

Theses and Dissertations

This research focused on developing a Cost Benefit Analysis process for Program Managers to implement when deciding what technical order format-- paper, computerized or automated--to purchase. Factors which determined the outcome are costs life cycle cost considering technical order format qualitative issues characteristics which are benefits of a technical order format and system responsiveness time required to develop or modify a technical order in each format. A literature review revealed problems with the paper technical order format, management infrastructure, quantitative cost estimates for different formats, and different techniques which could be used for a cost benefit analysis. Structured interviews were …


Developing A Template For Logistics Test And Evaluation, Timothy J. Fennell, Jason S. Mogle Sep 1994

Developing A Template For Logistics Test And Evaluation, Timothy J. Fennell, Jason S. Mogle

Theses and Dissertations

Logistics test and evaluation, performed during the developmental test and evaluation effort, is an integral part of the aircraft acquisition process. However, there has been no standard approach to conducting logistics test and evaluation. This study researched past and present approaches to aircraft logistics test and evaluation to determine the most effective method for future programs. We conducted this study using the Delphi method. We solicited the expert opinions of 32 individuals from the logistics test and evaluation field using two rounds of questions. We then statistically analyzed the data to ultimately develop a logistics test and evaluation template. We …


Benchmarking Customer Service Practices Of Air Cargo Carriers: A Case Study Approach, Patrick D. Lozon, Michael B. Mcdaniel Sep 1994

Benchmarking Customer Service Practices Of Air Cargo Carriers: A Case Study Approach, Patrick D. Lozon, Michael B. Mcdaniel

Theses and Dissertations

This study used the benchmarking process incorporated in a case study approach to determine what the Air Force could learn from the commercial air cargo carriers in regard to customer service practices. The air cargo industry leaders were determined through a previous study to be United Parcel Service, Federal Express, Emery Air Freight, Airborne Freight, DHL Airways, and Burlington Air Express. In addition, the 437th Aerial Port Squadron APS at Charleston AFB South Carolina was the Air Force representative in the benchmarking study. Interviews with air cargo managers were conducted at each carrier’s main hub and at Charleston AFB. The …


Logistics Control Facility: A Normative Model For Total Asset Visibility In The Air Force Logistics System, Eric C. Lorraine, Michael E. Michno Sep 1994

Logistics Control Facility: A Normative Model For Total Asset Visibility In The Air Force Logistics System, Eric C. Lorraine, Michael E. Michno

Theses and Dissertations

Computer simulation was used to evaluate the impact of a Logistics Control Facility LCF with a Total Asset Visibility TAV system on the AF logistics systems ability to support a weapon system. For this study, the B-1B was chosen as the weapon system of interest. Two performance measures, expected fully mission capable rates and expected pipeline quantities, were used to evaluate the simulation results. Two-sample tests were used to compare the current logistics configuration of the B-1B with the same configuration, but with an LCF controlling the movement of assets. The expected FMC rate performance measure showed significant results while …