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Theses and Dissertations

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Articles 10591 - 10620 of 11497

Full-Text Articles in Engineering

An Analysis Of Alternative Methods Of Measuring Hazardous Waste Reduction Progress At The Air Force Materiel Command's Air Logistic Centers, Edward C. Finke Sep 1994

An Analysis Of Alternative Methods Of Measuring Hazardous Waste Reduction Progress At The Air Force Materiel Command's Air Logistic Centers, Edward C. Finke

Theses and Dissertations

his study investigated the relationship between aircraft related maintenance activity and the amount of hazardous waste (HW) disposed of by Air Force Materiel Command's (AFMC) Air Logistic Centers (ALC). These ALCS, along with the Aircraft Guidance and Meteorology Center, generate approximately 76 percent of the HW generated by the Air Force. The activity indexing and least squares curve fitting methods were used to predict the amount of HW that would have been disposed of based on the relative level of aircraft related maintenance activity had no pollution prevention efforts been implemented. These predictions were then compared to what historically occurred …

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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 …

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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 …

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Analysis Of The Jplan Exercise As An Experimental Learning Tool, Mark J. Lynch, Michael E. Washington Sep 1994

Analysis Of The Jplan Exercise As An Experimental Learning Tool, Mark J. Lynch, Michael E. Washington

Theses and Dissertations

The purpose of this study is to develop an effective educational tool for the Combat Logistics course offered at the Air Force Institute of Technology. The current tool being used, the JPLAN Exercise, was identified as outdated in several areas. The research focused upon four investigative questions what makes an effective educational tool, should the existing exercise be revised or replaced, which logistics principles are essential for incorporation into the educational tool, and is the updated tool significantly different from the original. To answer these questions, we conducted an extensive literature review that focused on two areas. The first area …

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Organic Maintenance Performance Measurement: A New Approach, John S. Nehr, William G. Queener Sep 1994

Organic Maintenance Performance Measurement: A New Approach, John S. Nehr, William G. Queener

Theses and Dissertations

The growing role of Air Force Air Logistics Centers ALC in complex, multiyear developmental programs increases the need for effective cost and schedule performance measurement. In order to effectively manage these activities, timely and accurate cost and schedule information must be collected and compared with an established baseline. The ALCs need a new management technique which facilitates this type of performance measurement. A proven approach to cost and schedule performance measurement in weapon system acquisitions is Earned Value EV. This approach, required of contractors who are subjected to the CostSchedule Control Systems Criteria CSCSC, allows the program manager to obtain …

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A Maintenance Manpower Study Of The Composite Wing At Mountain Home Afb, Stella T. Smith, Cristina C. Vilella Sep 1994

A Maintenance Manpower Study Of The Composite Wing At Mountain Home Afb, Stella T. Smith, Cristina C. Vilella

Theses and Dissertations

In response to changes in threats, the Air Force has reorganized several flying units into composite wings. They are intended to provide a flexible, rapid deployment force. This study focused on the impact of the composite wing organizational structure on the determination of maintenance manpower authorizations at Mountain Home AFB, the Air Forces first air intervention wing. An opinion survey of maintenance and manpower experts was used to identify factors that are important in the determination of maintenance manpower authorization levels. Statistical analysis identified important-factors and indicated differences in opinion between maintenance and manpower specialists. Factors specific to the composite …

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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 …

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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 …

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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 …

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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 …

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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 …

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Evaluation Of Alternative Methods For Wastewater Disinfection, David C. Piech Sep 1994

Evaluation Of Alternative Methods For Wastewater Disinfection, David C. Piech

Theses and Dissertations

This study investigated the alternative methods of wastewater disinfection. Areas of interest included methods of operation, ease of maintenance, and effectiveness for various types of wastewater. A literature search revealed three major disinfection options, which include chlorination dechlorination, ultraviolet light, and ozone. A questionnaire was sent to the active duty Air Force installations that operate wastewater treatment plants, requesting permit limitations and monthly averages for a variety of wastewater parameters. The majority of Air Force wastewater treatment plants use chlorine for disinfection. Using the data obtained from the questionnaire responses and established wastewater parameters from other research, the basic design …

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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 …

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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 …

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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 …

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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.

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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. …

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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 …

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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, …

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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 …

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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 …

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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 …

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How Effective Has The Air Force Been In Eliminating Its Dependence On Ozone Depleting Chemicals?, L. Susan Willard Sep 1994

How Effective Has The Air Force Been In Eliminating Its Dependence On Ozone Depleting Chemicals?, L. Susan Willard

Theses and Dissertations

This research was undertaken to determine how effectively the Air Force had eliminated its dependence on Ozone Depleting Chemicals. The research was limited to analyzing the impact of ODCs on major acquisition programs. Results indicated existing variables which may be impeding full implementation. Also identified were lessons learned which could be applied to future environmental legislation with potential impact on acquisition programs. In- depth telephonic interviews were conducted with Program Directors responsible for the development and fielding of major Air Force acquisition programs. Analysis revealed that ODCs substantially impacted the acquisition programs to the extent that many programs had classified …

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Polynomial Real Root Finding In Bernstein Form, Melvin R. Spencer Aug 1994

Polynomial Real Root Finding In Bernstein Form, Melvin R. Spencer

Theses and Dissertations

This dissertation addresses the problem of approximating, in floating-point arithmetic, all real roots (simple, clustered, and multiple) over the unit interval of polynomials in Bernstein form with real coefficients.

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Modeling Of Ground Water Aquifer Remediation By Pulsed Pumping When Contaminant Transport Is Affected By Physical, Non-Equilibrium Sorption And Desorption, Jeffrey L. Caspers Aug 1994

Modeling Of Ground Water Aquifer Remediation By Pulsed Pumping When Contaminant Transport Is Affected By Physical, Non-Equilibrium Sorption And Desorption, Jeffrey L. Caspers

Theses and Dissertations

This research postulates and demonstrates a modification incorporating rate-limited sorption effects in the USGS SUTRA code for cleanup of a hypothetical sandy aquifer by pump-and-treat remediation methods. Contaminant transport is assumed to be affected by advection, dispersion, and rate-limited sorption/desorption. Sorption is assumed to be either equilibrium or rate-limited, with the rate-limitation described by either a first-order law, or by Fickian diffusion of contaminant through a spherical immobile pore region. Solutions are arrived at by split operator methods for the transport and one-dimensional Galerkin solutions for the solute concentration equations. The resulting model is tested against an analytical Laplace transform …

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Use Of Infrared Spectrometry To Determine The Effect Of Trichloroethylene Resident Time On Desorption Rates From Flint Clay, Peter T. Lapuma Aug 1994

Use Of Infrared Spectrometry To Determine The Effect Of Trichloroethylene Resident Time On Desorption Rates From Flint Clay, Peter T. Lapuma

Theses and Dissertations

This laboratory based thesis investigated the desorption rate of trichloroethylene (TCE) from flint clay while varying the resident time of TCE exposed to the clay. It is thought that in long contaminated soil, a majority of contaminant mass will become entrained within the interior of the soil particles to slowly desorb out of the soil over long periods of time. Recent studies suggest that the longer a contaminant is resident in soil, the longer the contaminant will take to desorb from the soil. To understand more about soil desorption, this experiment was developed using infrared spectroscopy to detect TCE vapor …

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Numerical Simulation Of Dynamic-Stall Suppression By Tangential Blowing, Matthew C. Towne Jul 1994

Numerical Simulation Of Dynamic-Stall Suppression By Tangential Blowing, Matthew C. Towne

Theses and Dissertations

The use of tangential blowing to suppress the dynamic stall of a pitching airfoil is investigated numerically. The laminar two-dimensional, compressible Navier-Stokes equations are solved time-accurately using a Beam- Warming algorithm. A slot is located at four different positions along the surface of a NACA 0015 airfoil and air is injected in a nearly tangential sense along the upper surface. Suction control is also employed at one of these slot locations to directly compare with tangential-blowing control. Solution sensitivity to grid refinement, time-step size, numerical smoothing, and initial conditions is investigated at a Reynolds number of 2.4 x 10exp 4. …

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A Diffraction-Based Model Of Anisoplanatism Effects In Adaptive Optic Systems, Steven E. Troxel Jun 1994

A Diffraction-Based Model Of Anisoplanatism Effects In Adaptive Optic Systems, Steven E. Troxel

Theses and Dissertations

This dissertation presents a new model for computing the angle dependent performance measures of an adaptive-optics system. By incorporating diffraction caused by the index-of-refraction variations of the atmosphere, the phase and amplitude fluctuations of the propagating wave are computed. New theory is presented, that uses the diffraction-based propagation model to yield optical transfer function (OTF) expressions that are more accurate as compared to current theory that neglects diffraction. An evaluation method for calculating the OTF is presented that utilizes a layered atmospheric model and normalized OTF expressions. The diffraction model is also used to present the first OTF signal-to-noise ratio …

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The Excitation Mechanism Of Praseodymium-Doped Semiconductors, Paul L. Thee Jun 1994

The Excitation Mechanism Of Praseodymium-Doped Semiconductors, Paul L. Thee

Theses and Dissertations

This study on praseodymium Pr luminescence in AlxGa1-xAs was conducted to enhance the understanding of the excitation mechanism. Pr was implanted at 390 keV with doses from 5 x 1012 to 5 x 1013 sq cm into AlxGa1-xAs x0.0 to 0.50 wafers which were annealed using the rapid thermal annealing RTA method. Low temperature photoluminescence PL was conducted using an Ar-ion laser and Ge detector. PL emissions of Pr from all hosts include peaks near 1.3 and 1.6 µm which are assigned to the intra-4f transitions of 1G4 yielding 3H5 …

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Calibration And Initial Testing Of A New Hydraulic Simulator, Cristian A. Puebla Jun 1994

Calibration And Initial Testing Of A New Hydraulic Simulator, Cristian A. Puebla

Theses and Dissertations

In the present research, the flow field associated with the ejection of a crew capsule from the fuselage of a high speed generic aircraft was experimentally investigated by means of the modified gas hydraulic analogy. For this, an existing hydraulic simulator was calibrated and modified to adapt it to the needs of the experiment. The analogy was evaluated for a five-sided capsule alone, and good quantitative agreement with the 2-D shock-expansion theory was obtained. It was found that the size of the model played a key role in the determination of good quantitative data. The analysis of the capsule interacting …

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