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The Relationship Between Personality And Alcohol Abuse Among College Students, Amanda L. Alexander Apr 2001

The Relationship Between Personality And Alcohol Abuse Among College Students, Amanda L. Alexander

Theses and Dissertations

Alcohol abuse is a widespread problem on college campuses. It can lead to social, academic and physical consequences. Motivating factors for alcohol abuse include stress reduction, social acceptance and personality. The purpose of the present study was to determine a link between alcohol abuse and personality. The study has 53 female participants ranging in age from 18 to 26. It was hypothesized that females classified as binge drinkers would score significantly higher or lower on certain personality facets compared to females classified as non-binge drinkers. The IPILP-NEO and an alcohol use questionnaire were used to assess each participant's ranking on …

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The Effects Of Household Substance Abuse On The Behavioral And Emotional Outcomes Of Child Witnesses To Domestic Violence, Katherine R. Destefano Apr 2001

The Effects Of Household Substance Abuse On The Behavioral And Emotional Outcomes Of Child Witnesses To Domestic Violence, Katherine R. Destefano

Theses and Dissertations

Both domestic violence and parental substance abuse are risk factors for childhood developmental delays and emotional problems. The purpose of this study is to determine if child witnesses of domestic violence exhibit greater levels of emotional problems when substance abuse is present in the household, and to determine how both groups of children respond to therapeutic intervention targeting these problems. The results indicate that child witnesses of domestic violence exhibit a greater level of behavioral and emotional problems when alcohol and drug abuse is also a factor. Following treatment both groups show a greater reduction in behavioral and emotional pathology …

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A Review Of The Benefits Of Flax Supplementation, Samuel P. Held Apr 2001

A Review Of The Benefits Of Flax Supplementation, Samuel P. Held

Theses and Dissertations

We have become a society of convenience. Healthy foods that were staples for thousands of years have become replaced by processed foods with long shelf lives. This has been done to the detriment of our nutrition and health. Flax is one such replaced food item. A staple food for hundreds of generations, flax had become scarce in our diet until recent interest spurred by research found flax to be one of the best sourc es on earth for alpha-linolenic acid an Omega- three fatty acid, plant lignans, and contains a large amount of dietary fiber. Potentially these constituents can have …

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Hidden Markov Models For Visual Speech Synthesis In Limited Data, Harold A. Arb Mar 2001

Hidden Markov Models For Visual Speech Synthesis In Limited Data, Harold A. Arb

Theses and Dissertations

This work presents a new approach for estimating control points (facial locations that control movement) to allow the artificial generation of video with apparent mouth movement (visual speech) time-synced with recorded audio. First, Hidden Markov Models (HMMs) are estimated for each visual speech category (viseme) present in stored video data, where a category is defined as the mouth movement corresponding to a given sound and where the visemes are further categorized as trisemes (a viseme in the context of previous and following visemes). Next, a decision tree is used to cluster and relate states in the HMMs that are similar …

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Sibling Effects In The Adjustment Of Children Exposed To Domestic Violence, Nicole L. Mccann Mar 2001

Sibling Effects In The Adjustment Of Children Exposed To Domestic Violence, Nicole L. Mccann

Theses and Dissertations

Many studies discuss how the emotional trauma experienced by children of divorcing parents is buffered by the presence of siblings. The present study examines whether there is a similar buffering sibling effect for child witnesses to domestic violence if there is an older sibling present in the household. This study examined the differences between first born children including only children and younger siblings who have witnessed domestic violence. The Trauma Symptom Checklist and the Child Behavior Checklist were administered to 102 children aged 3-11 whose parent received shelter or outreach counseling at a New Jersey battered women's shelter. Demographic information …

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Spectroscopic Constants, Lifetimes And Predissociation Rates For Bi2A(0+U), Michael W. Dolezal Mar 2001

Spectroscopic Constants, Lifetimes And Predissociation Rates For Bi2A(0+U), Michael W. Dolezal

Theses and Dissertations

More than 100,000 spectral features from a Bi2(X1 Σ+g → A(0+u)) absorption spectrum, encompassing 0 ≤ v' ≤ 91, 0 ≤ v" ≤ 7 and J2(A). Ground state constants, reported by Barrow et al. [1], remain unchanged. The new constants are used to redefine the A-state potential using traditional RKR methods and to set the dissociation energy at De = 29,913 cm"1, which correlates A-state dissociation products to 4S + 2D atoms. A pulsed dye laser apparatus was used to obtain lifetime data for Bi2A(0+u) …

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Identification Of Preferred Operational Plan Force Mixes Using A Multiobjective Methodology To Optimize Resource Suitability And Lift Cost, David J. Wakefield Jr. Mar 2001

Identification Of Preferred Operational Plan Force Mixes Using A Multiobjective Methodology To Optimize Resource Suitability And Lift Cost, David J. Wakefield Jr.

Theses and Dissertations

AFIT research in support of the Advanced Logistics Project is directed at developing a Mission-Resource Value Assessment Tool for rationally assigning relative value to resources and identifying alternative force mixes to logistics and operational planners. Research of factors that affect force mix composition has been strictly limited to how the operating environment of USAF combat aircraft influences their performance in specified aerospace missions. In contrast, this research makes use of an aircraft's designed suitability to perform specified aerospace missions in order to examine the tradeoff between mission suitability and the amount of lift needed to deploy and operate the asset. …

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Jp-8+100lt: A Low Cost Replacement Of Jpts As The Primary Fuel For The U-2 Aircraft, Christian G. Simms Mar 2001

Jp-8+100lt: A Low Cost Replacement Of Jpts As The Primary Fuel For The U-2 Aircraft, Christian G. Simms

Theses and Dissertations

The Air Force currently spends approximately $ 10 million dollars annually on fuel support for the U-2 aircraft. The U-2 has used a jet fuel known as JPTS since the aircraft's development in the 1950's. JPTS is a specialty fuel used only by the U-2 and is produced by two oil refineries in the United States. As such, it has limited worldwide availability and costs over three times the per-gallon price of the Air Force's primary jet fuel, JP-8. Recent research performed at the Air Force Research Laboratory Propulsion Directorate suggests that additives could be added to JP-8, which would …

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Adaptive And Reconfigurable Flight Control, Yih Shiun Huang Mar 2001

Adaptive And Reconfigurable Flight Control, Yih Shiun Huang

Theses and Dissertations

An indirect adaptive and reconfigurable flight control system is developed. The three-module controller consists of: (1) a system identification module, (2) a parameter estimate smoother, and (3) a proportional and integral compensator for tracking control. Specifically: (1) The identification of a linear discrete-time control system's open-loop gain is addressed. The classical Kalman filter theory for linear control systems is extended and the control system's state and loop gain are jointly estimated on-line. Explicit formulae for the loop gain's estimate and estimation error covariance are derived. The estimate is unbiased and the predicted covariance is reliable. (2) An adaptive smoother is …

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Evolution Of Cloud-To-Ground Lightning Discharges In Tornadic Thunderstorms, Wendy L. Seaman Mar 2001

Evolution Of Cloud-To-Ground Lightning Discharges In Tornadic Thunderstorms, Wendy L. Seaman

Theses and Dissertations

Air Force operations are directly impacted by weather on a daily basis. Erroneous forecasts negatively impact mission readiness and consequently cost the government time, in terms of wasted man-hours, and money. Advanced forecast lead-time could make a difference to minimize loss to both USAF personnel and assets. This study examined lightning data from 64 storm events from 1995-2000 in search of unique lightning signatures indicative of tornadic activity. Overall flash rates, percentage of positive flashes, positive and negative peak currents and multiplicity for each case were separated into two categories based on tornado intensity and season of occurrence. Based on …

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A Multi-Objective Decision Support Model For The Turkish Armed Forces Personnel Assignment System, Zubeyir Cimen Mar 2001

A Multi-Objective Decision Support Model For The Turkish Armed Forces Personnel Assignment System, Zubeyir Cimen

Theses and Dissertations

The Turkish Armed Forces (TAF) assign more than 25,000 active duty personnel annually. TAF wants to obtain maximum utilization of its personnel by assigning the right person to the right job at the right time, To accomplish this task, decision-makers and personnel assignment staff should consider conflicting multiple objectives that create the widely known problem called "personnel assignment problem". To assist in this complicated task from a quantitative perspective, a preemptive goal programming approach was used to develop an integer programming (IP) model to capture the multiple objectives flexibly and interactively. A realistic size IP problem with random data was …

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Spectral And Temporal Characterization Of High Temperature Events, William F. Bagby Mar 2001

Spectral And Temporal Characterization Of High Temperature Events, William F. Bagby

Theses and Dissertations

The remote observations of the temporal and spectral characteristics of the infrared (IR) emissions from exploding ordnance have been correlated with explosion conditions. A Bomem MR-154 Fourier Transform Interferometer with two detectors, InSb and HgCdTe, was used to record spectra in the 1.3 - 20 micrometers range. Data was collected at spectral resolutions of 16/cm and 4/cm, and temporal resolutions of 0.045 sand 0.123 5, respectively. The data files range in size from 900 Kilobytes to several Megabytes. These are reduced to 2-dimensional representations of temporal features that are less than 100 Kilobytes. The data analysis indicates the possibility of …

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Aircraft Maintenance Performance: The Effects Of The Functional Decentralization Of On-Equipment Maintenance, Mark A. Commenator Mar 2001

Aircraft Maintenance Performance: The Effects Of The Functional Decentralization Of On-Equipment Maintenance, Mark A. Commenator

Theses and Dissertations

The Air Force has implemented various aircraft maintenance organizational structures. The implementation of the Objective Wing in the early 1990s was the latest occurrence of reorganization. This research looks at the effect of the type of aircraft maintenance organizational structure on aircraft maintenance performance. The type of organizational structure was defined by the functional centralization of the on-equipment maintenance. Aircraft maintenance performance was measured using TNMCM rates, fix rates, repeat/recur rates, man-hours per flying hour, and scheduling effectiveness rates. Three F-15 wings and three F-16 wings were selected to compare the changes in aircraft maintenance performance and to determine if …

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Characterization And Validation Of The Gp-3 Experimental Radar System, Benjamin L. Crossley Mar 2001

Characterization And Validation Of The Gp-3 Experimental Radar System, Benjamin L. Crossley

Theses and Dissertations

The experimental GP-3 radar system was originally designed and built under contract for the Air Force Research Laboratory (AFRL). AFRL sought AFIT's support in characterizing the as delivered' performance of the GP-3. This research effort focused exclusively on software modifications and hardware validations related to the GP-3 post-processing mode. As modified, tested, and validated, the GP-3's post-processing mode is now fully operational. The GP-3 is capable of transmitting and receiving bandlimited (3.5 MHz) waveforms at X-Band frequencies. System characterization tests included, noise performance and frequency response. System noise performance characterization permitted establishment of the receiver 'noise floor' and enabled determination …

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Comparative Analysis Of Traditional Versus Computer-Based Survey Instrument Response, Albert E. Franke Iv Mar 2001

Comparative Analysis Of Traditional Versus Computer-Based Survey Instrument Response, Albert E. Franke Iv

Theses and Dissertations

The purpose of this study was to determine if survey medium (paper versus computer) affected responses and response rates in Air Force personnel. The study compared responses and response rates from 900 randomly selected Air Force active-duty members using a paper-based survey, a computer-based survey, and a more complex computer-based survey. The first computer-based survey minimized the differences between itself and the paper-based survey to more accurately quantify any bias due solely to the computer medium. The more complex survey served to maximize differences between itself and the other computer-based survey to more accurately quantify any bias due to programmatic …

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Analysis Of The Application Of A Triggered Isomer Heat Exchanger As A Replacement For The Combustion Chamber In An Off-The-Shelf Turbojet, Carl R. Hartsfield Mar 2001

Analysis Of The Application Of A Triggered Isomer Heat Exchanger As A Replacement For The Combustion Chamber In An Off-The-Shelf Turbojet, Carl R. Hartsfield

Theses and Dissertations

The objective of this research was to evaluate the feasibility of using the triggered decay of a radioactive isomer in a solid-state heat exchanger to power a gas turbine engine. Primary performance measures were stagnation temperature increase and stagnation pressure drop across the heat exchanger. Analysis was performed using commercial software, and explored three types of heat exchanger: concentric tubes, radial fins with constant spacing, and radial fins with constant thickness. All met or exceeded performance of the baseline J-57 turbojet engine at static sea level conditions. A single configuration of heat exchanger, using concentric tubes, was evaluated at typical …

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Analysis Of The Effect Of Centralizing Management Of Mobility Readiness Spares Package Assets, Ian R. Hester Mar 2001

Analysis Of The Effect Of Centralizing Management Of Mobility Readiness Spares Package Assets, Ian R. Hester

Theses and Dissertations

Air Force supply doctrine requires the management of large numbers of spare parts in Mobility Readiness Spares Packages (MRSPs). The MRSPs are designed to support deployed aircraft for the first 30 days of a conflict, and can be quite large. When units from several bases deploy to the same operating location, they each bring their full MRSP. This results in a large logistics footprint that may be reduced by taking a system-level approach. This thesis examined the impact of centralized MRSP management on kit size and cost. The Aircraft Sustainability Model (ASM) computer program was used to evaluate MRSPs for …

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Utility Of Experimental Design In Automatic Target Recognition Performance Evaluation, James M. Higdon Mar 2001

Utility Of Experimental Design In Automatic Target Recognition Performance Evaluation, James M. Higdon

Theses and Dissertations

This research investigates current practices in test and evaluation of classification algorithms, and recommends improvements. We scrutinize the evaluation of automatic target recognition algorithms and rationalize the potential for improvements in the accepted methodology. We propose improvements through the use of an experimental design approach to testing. We demonstrate the benefits of improvements by simulating algorithm performance data and using both methodologies to generate evaluation results. The simulated data is varied to test the sensitivity of the benefits to a broad set of outcomes. The opportunities for improvement are threefold. First, the current practice of 'one-at-a-time factor variation (only one …

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Evaluation Of The Air Force's Alternative Fuel Vehicle Program In Complying With Executive Order 13149, Janette D. Ketchum Mar 2001

Evaluation Of The Air Force's Alternative Fuel Vehicle Program In Complying With Executive Order 13149, Janette D. Ketchum

Theses and Dissertations

The Air Force must comply with Executive Order (E.O.) 13149, which includes cutting its vehicle fleet's petroleum fuel usage 20 percent by 2005. This thesis examines the Air Force's current alternative fuel vehicle (AFV) program, which is centered around the acquisition and use of compressed natural gas (CNG) vehicles, to determine whether it has been effective, and how the AFV program should be tailored to contribute to the Air Force's efforts to comply with E.O. 13149. The results of the study discussed here suggest ways in which the Air Force's AFV program can be modified to increase the program's impact …

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Vibration Suppression Of A Rotationally Periodic Structure Using An Adaptive/Ppf Control Law, Mark J. Keller Mar 2001

Vibration Suppression Of A Rotationally Periodic Structure Using An Adaptive/Ppf Control Law, Mark J. Keller

Theses and Dissertations

For a compressor disk, effective vibration suppression requires broadband control, and the elimination of inter-blade coupling forces. Previous researchers achieved this using an active/passive piezoelectric shunt network. Unfortunately, optimal tuning of the shunt requires prior knowledge of the coupling strength, which is not well defined. This thesis uses an adaptive parameter estimator to eliminate the inter-blade coupling forces. In addition, the passive shunt is replaced with an analogous positive position feedback method. The resulting control law was used on a simulated four and eight bladed system. While substantial reductions in system response were achieved for the Adaptive/PPF control technique, the …

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Pitfalls Of The A-76 Process, Justin W. Lavadour Mar 2001

Pitfalls Of The A-76 Process, Justin W. Lavadour

Theses and Dissertations

The DoD and the Air Force have turned to outsourcing support functions as a way to reduce both costs and the number of soldiers required to provide Support for combat forces. The process used to determine whether it is economically feasible to outsource a function is called A-76, after the circular that describes the process. Outsourcing, like any other tool, must be used in the right way, in the correct environment if the desired goal to be reached. To understand what these goals are, it is necessary to examine past case studies where outsourcing has worked, to determine why outsourcing …

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Chromate Content Bias As A Function Of Particle Size In Aircraft Primer Paint Overspray, David B. Novy Mar 2001

Chromate Content Bias As A Function Of Particle Size In Aircraft Primer Paint Overspray, David B. Novy

Theses and Dissertations

Spray painting operations using chromate-containing primer paints produce particles which may expose workers to strontium chromate. Chromate contains hexavalent chromium (Cr(VI)) which is a confirmed human carcinogen. It is suspected that the smaller particles contain disproportionately less Cr(VI) than larger particles. In order to determine if a bias in chromate content exists, paint particles were collected and separated based on particle size and the Cr(VI) concentration was determined. Aviation primer paint from the DeSoto and Deft companies was sprayed in a booth and seven-stage cascade impactors were used to separate particles.

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Software Domain Model Integration Methodology For Formal Specifications, Joel C. Nonnweiler Mar 2001

Software Domain Model Integration Methodology For Formal Specifications, Joel C. Nonnweiler

Theses and Dissertations

Using formal methods to create automatic code generation systems is one of the goals of Knowledge Based Software Engineering (KBSE) groups. The research of the Air Force Institute of Technology KBSE group has focused on the utilization of formal languages to represent domain model knowledge within this process. The code generation process centers around correctness preserving transformations that convert domain models from their analysis representations through design to the resulting implementation code. The diversity of the software systems that can be developed in this manner is limited only by the availability of suitable domain models. Therefore it should be possible …

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Effects On The Red-Cockaded Woodpecker From Various Spatial And Temporal Applications Of Management Practices, Chad F. Schroeder Mar 2001

Effects On The Red-Cockaded Woodpecker From Various Spatial And Temporal Applications Of Management Practices, Chad F. Schroeder

Theses and Dissertations

The Red-Cockaded Woodpecker (RCW) is an endangered species endemic to southeastern pine forests in the United States. RCWs are cooperative breeding birds that live together in clusters of old-growth pine trees in which they construct their nesting cavities. The cavities are constructed in living pines, which are predominantly longleaf pines. RCWs also forage upon older pines, preferably longleaf pine. The Endangered Species Act, along with other DoD regulations, requires DoD installations to protect the RCWs and restore their habitat. A popular management practice converts off-site (non-native) pines back to a region's indigenous pines. Conversion provides the best long term RCW …

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A Case Study Analysis Of The Overhead Rate Impact Model Used During The C-5 Maintenance Source Selection, William N. Ward Mar 2001

A Case Study Analysis Of The Overhead Rate Impact Model Used During The C-5 Maintenance Source Selection, William N. Ward

Theses and Dissertations

The Overhead Rate Impact (ORI) model was used during the C-5 Maintenance source selection to evaluate the impact the new workload would have on the existing overhead rates. The objectives of this research study were to evaluate the ORI model and to identify the lessons learned from this source selection. To accomplish these objectives, interviews were conducted with members of the source selection team who were on the Cost Integrated Product Team (IPT). The experts were asked to identify the strengths and weaknesses of the ORI model and to make recommendation on how to improve the model. This study identified …

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The Effect Of Contextual-Based Training On Artifact-Based Deception Detection, Elizabeth A. Autrey Mar 2001

The Effect Of Contextual-Based Training On Artifact-Based Deception Detection, Elizabeth A. Autrey

Theses and Dissertations

Air Force dependence on information technology (IT) creates vulnerabilities that it cannot ignore. With global availability of commercial IT and the Internet, the Air Force does not necessarily have the high technological advantage over potential adversaries that it once had. Furthermore, it is possible to directly and covertly manipulate information within information systems, or artifacts, without notice. This directly affects decision makers since the availability and integrity of information is critical. Air Force physical and network security measures taken to protect its information do not guarantee detection of direct information manipulation. This leaves it to information artifact users to detect …

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The Distributer's Three-Dimensional Pallet-Packing Problem: A Human Intelligence-Based Heuristic Approach, Erhan Baltacioglu Mar 2001

The Distributer's Three-Dimensional Pallet-Packing Problem: A Human Intelligence-Based Heuristic Approach, Erhan Baltacioglu

Theses and Dissertations

The Distributor's Pallet Packing Problem is to load a set of distinct boxes with given dimensions on pallets or in containers to maximize volume utilization. This problem is still in its early stages of research, but there is a high level of interest in developing effective models to solve this NP-hard problem to reduce the time, energy and other resources spent in packing pallets. In its search to improve operations, the Air Force is also making an effort to solve this problem. Building an analytical model and developing a genetic algorithm approach have been tried, but the problem needs more …

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An Evaluation Of Information Technology (It) Outsourcing Determinants Within The Department Of Defense (Dod), Alexander J. Barelka Mar 2001

An Evaluation Of Information Technology (It) Outsourcing Determinants Within The Department Of Defense (Dod), Alexander J. Barelka

Theses and Dissertations

Each year the Department of Defense (DoD) spends billions of dollars on information technology (IT) outsourcing. However, little formal or academic guidance has appeared that explains how, why, or even when this occurs. This study presents and evaluates several determinants that may impact a decision to outsource information technology systems in the Department of Defense. It begins with the development of a conceptual model, which was created using semi-structured interviews and an extensive literature search. This model was then matured into an analytic version by using the Delphi method, which is an accepted methodology to use when insufficient or no …

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Modeling Information Assurance, Joseph E. Beauregard Mar 2001

Modeling Information Assurance, Joseph E. Beauregard

Theses and Dissertations

The ever-increasing speed of information systems allows decision-makers around the world to gather, process, and disseminate information almost instantaneously. However, with this benefit there comes a price. Information is valuable and therefore a target to those who do not have it or wish to destroy it. The Internet has allowed information to flow freely, but it has also made information vulnerable to many forms of corruption. The U. S. military controls much of the world's most sensitive information, and since it cannot sacrifice losing the speed at which this information is currently processed and disseminated, it must find a way …

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Photoluminescence Of Single Quantum Well Structures In Gallium Arsenide, Christian A. Bartholomew Mar 2001

Photoluminescence Of Single Quantum Well Structures In Gallium Arsenide, Christian A. Bartholomew

Theses and Dissertations

The continued development of state-of the-art semiconductor technologies and devices by the United States Air Force and the Department of Defense requires accurate and efficient techniques to evaluate and model these new materials. Of particular interest to the Air Force are quantum well structures which can be used for small-scale laser sources in fly-by-light applications, as efficient infrared countermeasures to heat-seeking missiles, or as advanced seekers in optically guided missiles. This thesis provides the initial experimental procedures and data necessary to begin producing accurate yet robust models. Although carrier effective masses could not be evaluated using hot-electron photoluminescence, photoluminescence excitation …

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