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Air Force Institute of Technology

2006

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Development Of In-Plane Surface Deformation Sensing For Thin Film Pvdf Actuated Membrane Mirrors, John J. Cornelius Mar 2006

Development Of In-Plane Surface Deformation Sensing For Thin Film Pvdf Actuated Membrane Mirrors, John J. Cornelius

Theses and Dissertations

This study investigated the feasibility of surface deformation sensing of a membrane mirror using only embedded PVDF sensors. Results were compared to measured deformations using a scanning laser vibrometer. The frequency response function (FRF) was measured based on recorded voltages of a single-layer 7-sensor mirror actuated externally from the embedded PVDF actuators. Additionally, a two-layer, 7-sensor, 7-actuator membrane mirror was constructed for use, with one layer acting as the sensing layer and the other acting as the actuation layer. The measured FRF for this mirror was compared to previous results. Finally a single-layer 61-sensor PVDF mirror was constructed to experimentally …

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Exploiting Semi-Directional Transceivers For Localization In Communication Systems, Andrew S. Crockford Mar 2006

Exploiting Semi-Directional Transceivers For Localization In Communication Systems, Andrew S. Crockford

Theses and Dissertations

Localization is the process of determining relative, as well as absolute, positions of communicating devices. Traditionally, the process is conducted using range or directional estimates. In contrast, this research uses weak information to form relatively tight bounds on possible locations of communicating devices. Under certain conditions, achieved location estimation results are strong. However, these results are highly sensitive to the operating conditions of the proposed networks. More significant results were obtained from specialized cases and that the application yields somewhat limited information for a general randomized network topology. Feasible localization results were found to be attainable but not necessarily practical …

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Data Analysis And Its Impact On Predicting Schedule & Cost Risk, Steven M. Cross Mar 2006

Data Analysis And Its Impact On Predicting Schedule & Cost Risk, Steven M. Cross

Theses and Dissertations

Many databases rely on documents (research) of the past to input data to create a comprehensive database. The Selected Acquisition Report (SAR) is one such document. The SARs are pervasive documents that have undergone decades of scrutiny by Congress and watchdog organizations such as the Government Accountability Office. Since the SAR has undergone such massive evolutionary changes, creating an accurate acquisition database presents a daunting task for the analyst and researcher alike. This research concerns itself with one such database. From this prior research database, we look to fill in missing data. We first conduct a literature review to determine …

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Passive Ranging Using Atmospheric Oxygen Absorption Spectra, Michael R. Hawks Mar 2006

Passive Ranging Using Atmospheric Oxygen Absorption Spectra, Michael R. Hawks

Theses and Dissertations

The depth of absorption bands in observed spectra of distant, bright sources can be used to estimate range to the source. A novel approach is presented and demonstrated using observations of the oxygen absorption band near 762 nm. Range is estimated by comparing observed values of band-average absorption against curves derived from either historical data or model predictions. Curves are based on fitting a random band model to the data, which reduces average range error by 67% compared to the Beer's Law model used in previous work. A new modification to existing band models for long, inhomogeneous paths is presented …

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Spatially-Resolved Temperature Diagnostic For Supersonic Flow Using Cross-Beam Doppler-Limited Laser Saturation Spectroscopy, Grady T. Phillips Mar 2006

Spatially-Resolved Temperature Diagnostic For Supersonic Flow Using Cross-Beam Doppler-Limited Laser Saturation Spectroscopy, Grady T. Phillips

Theses and Dissertations

Optical techniques for measuring the temperature in three-dimensional supersonic reactive flows have typically depended on lineshape measurements using single-beam laser absorption spectroscopy. However, absorption over extended path lengths in flows with symmetric, turbulent eddies can lead to systematically high extracted temperatures due to Doppler shifts resulting from flow along the absorption path. To eliminate these problems, Cross-Beam Saturation Absorption Spectroscopy (CBSAS) and Cross-Beam Inter-Modulated Fluorescence (CBIMF) have been developed which utilize two crossed and nearly copropogating laser beams.to record the spectral signal of an I2 ro-vibrational line in a small three-dimensional volume using a tunable CW dye laser. Temperature …

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Characterization Of Detonation Phenomena Observed In High-Speed Visible Imagery, Trevor W. Warren Mar 2006

Characterization Of Detonation Phenomena Observed In High-Speed Visible Imagery, Trevor W. Warren

Theses and Dissertations

Measurements for radius, angular velocity, initial time of observation, and final time of observation were made for turbulent vortices around detonation fireballs. A proxy for vortex power, determined through unit analysis, was found to correlate well to initial (and final) time of observation with R2 equal to 0.8572. The linear trend on a log10-log10 plot was indicative of a rapid decrease (over 10-1 s) in power associated with the decay of the fireball. Predictions, based on turbulent spectral theory were made for root-mean-square velocity fluctuations and Reynolds numbers, both as functions of time. In addition, …

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Quantitative Object Reconstruction Using Abel Transform Tomography And Mixed Variable Optimization, Kevin R. O'Reilly Mar 2006

Quantitative Object Reconstruction Using Abel Transform Tomography And Mixed Variable Optimization, Kevin R. O'Reilly

Theses and Dissertations

Researchers at the Los Alamos National Laboratory (LANL) are interested in quantitatively reconstructing an object using Abel transform x-ray tomography. Specifically, they obtain a radiograph by x-raying an object and attempt to quantitatively determine the number and types of materials and the thicknesses of each material layer. Their current methodologies either fail to provide a quantitative description of the object or are generally too slow to be useful in practice. As an alternative, the problem is modeled here as a mixed variable programming (MVP) problem, in which some variables are nonnumeric and for which no derivative information is available. The …

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Doppler-Only Multistatic Radar, Dustin G. Mixon Mar 2006

Doppler-Only Multistatic Radar, Dustin G. Mixon

Theses and Dissertations

In order to estimate the position and velocity of a target, most multistatic radar systems require multiple independent target measurements, such as angle-of-arrival, time-of-arrival, and Doppler information. Though inexpensive and reliable, Doppler-only systems have not been widely implemented due to the inherent nonlinear problem of determining a target’s position and velocity from their measurements. We solve this problem. In particular, we first establish the lack of observability in the Doppler-only bistatic system, thereby demonstrating the need for multiple transmitters and/or receivers. Next, for a multistatic system with a sufficient number of transmitter-receiver pairs, we invoke classical optimization techniques, such as …

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A Climatological Study Of Equatorial Gps Data And The Effects On Ionospheric Scintillation, Katharine A. Wicker Mar 2006

A Climatological Study Of Equatorial Gps Data And The Effects On Ionospheric Scintillation, Katharine A. Wicker

Theses and Dissertations

Ionospheric scintillation is detrimental to radio signals, especially those from the global positioning system. Such scintillation is caused when a signal permeates the ionosphere through plasma bubbles. The signal’s phase and amplitude can be altered, and a receiver on the ground can lose lock on the GPS signal. Measured using a zero to one index known as S4, scintillation severity is based upon season, solar cycle, time of day, location and frequency. The most severe scintillation occurs at the equatorial anomaly, or fifteen degrees north and south of the equator. Seven years of data from fifteen different locations around the …

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Selecting Energy Efficient Building Envelope Retrofits To Existing Department Of Defense Building Using Value Focused Thinking, David M. Pratt Mar 2006

Selecting Energy Efficient Building Envelope Retrofits To Existing Department Of Defense Building Using Value Focused Thinking, David M. Pratt

Theses and Dissertations

The Department of Defense (DoD) has hundreds of thousands of facilities in its inventory, which consume billions of BTUSs of energy per year. Much of that energy is used to heat and cool the facility, and a great deal of this energy is lost through the building envelope. While new military construction works towards energy efficiency, the majority of DoD facilities were built over forty years ago with little regard to energy efficiency, and it is these facilities that have the greatest potential for energy efficient building envelope retrofits. There are hundreds of various new building envelope technologies available to …

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In Vitro Toxicity Of Aluminum Nanoparticles In Rat Alveolar Macrophages, Andrew J. Wagner Mar 2006

In Vitro Toxicity Of Aluminum Nanoparticles In Rat Alveolar Macrophages, Andrew J. Wagner

Theses and Dissertations

Nanomaterials, which are by definition in the 1 - 100 nanometer range, have numerous possible benefits to society, but currently there is a lack of data that characterizes these materials effects on human health and environment. In general nanomaterials are of interest to the Air Force because of their applications in electronics, sensors, munitions and energetic/reactive systems. Nanoparticles such as aluminum have been considered for enhancing propulsion in solid rocket fuel. To date, only a few studies have looked at the toxicological effects of direct exposure to nanoparticles, none with aluminum. It is important to increase the understanding of the …

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Corporate Entrepreneurship Assessment Instrument (Ceai): Systematic Validation Of A Measure, Tassika M. Davis Mar 2006

Corporate Entrepreneurship Assessment Instrument (Ceai): Systematic Validation Of A Measure, Tassika M. Davis

Theses and Dissertations

The implementation of corporate entrepreneurship is becoming an important activity for private- and public-sector organizations. Organizational factors have been linked to successful corporate entrepreneurship. The Corporate Entrepreneurship Assessment Instrument (CEAI) is an instrument that attempts to measure the effectiveness of the key internal organizational factors, or climate, that influence innovative activities and behaviors. This study attempted to assess the content validity and factor structure of the CEAI and thus add weight to the psychometric soundness of the instrument. In sum, the effectiveness of the instrument was tested using the framework for scale development presented by Hinkin (1998). Overall, the CEAI …

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An Asymmetrical Look At Air Force Human Capital Management: More Emphasis On Qualifications And Less On Rank, Daniel M. Romano Mar 2006

An Asymmetrical Look At Air Force Human Capital Management: More Emphasis On Qualifications And Less On Rank, Daniel M. Romano

Theses and Dissertations

This research explored an asymmetrical concept of personnel management, specifically whether status, rank, is an artificial barrier to employing qualified enlisted personnel in some company grade officer duties. It takes the approach under the Human Capital Theory and questions whether rank plays a roll in effective performance and whether eliminating rank as a criterion to employment, in some duties, can support Air Force transformation efforts, without negatively affecting culture (i.e. chain-of-command, customs and courtesies). It describes a concept where more emphasis is put on meeting the knowledge, education, experience, and training qualifications and the required rank be interchangeable between enlisted …

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Challenges Facing Military Organizational Cultural Reform: A Study Of The 2004 Air Force Materiel Command Reorganization, Joy D. Mikulcik Mar 2006

Challenges Facing Military Organizational Cultural Reform: A Study Of The 2004 Air Force Materiel Command Reorganization, Joy D. Mikulcik

Theses and Dissertations

The purpose of this research was to measure the success of the Product Center (PC) portion of the Air Force Materiel Command (AFMC) reorganization initiated in 2004. The purpose of this study is threefold, 1) to determine if the 2004 AFMC Product Center reorganization has met General Martin's four intended objectives, (2) the reorganizations effects on AFMC employee job satisfaction and organizational commitment and (3) to gather some general opinions about the reorganization overall. The literature review consisted of a detailed look at the history of AFMC, areas of organizational culture, and gathering detailed information regarding the 2004 reorganization itself. …

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Acquisition Program Re-Baselines: Theory And Practice, Troy A. Suarez Mar 2006

Acquisition Program Re-Baselines: Theory And Practice, Troy A. Suarez

Theses and Dissertations

The United States Government requires every program manager in the Department of Defense to document program goals prior to the initiation of an acquisition program. According to the Defense Acquisition Guidebook (2005), an Acquisition Program Baseline (APB) satisfies this requirement. Updating the APB, also referred to as re-baselining, may also be required during the execution of an acquisition program. Although guidance is available for the initial production of a program baseline, scarce information on the guidance and theoretical purpose of a program re-baseline exists. The research presented in this thesis investigated the purpose and effectiveness of program re-baselines through interviews …

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Understanding Innovation Adoption In The Air Force, Morgan J. Evans Mar 2006

Understanding Innovation Adoption In The Air Force, Morgan J. Evans

Theses and Dissertations

Innovation adoption has become a critical issue for organizations in both the public and private sectors. The search for competitive advantage has led to the recognition that innovation is a vital ingredient for an organization's survival and profitability in this information age. The United States Air Force is seeking to adapt to this new information age by transforming its business processes in order to sustain its competitive advantage as the world's most respected air force. Adopting innovations and integrating new or improved technologies, capabilities, concepts, and processes into Air Force planning and acquisition activities, organizations, and operations are goals of …

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An Exploratory Case Study Of Information-Sharing And Collaboration Within Air Force Supply Chain Management, Wendy S. Kierpiec Mar 2006

An Exploratory Case Study Of Information-Sharing And Collaboration Within Air Force Supply Chain Management, Wendy S. Kierpiec

Theses and Dissertations

This research sought to identify key elements of the Air Force supply chain as it relates to industry, determine how techniques of information-sharing and collaboration are used to make Air Force Supply Chain decisions, and examine how the resulting impacts on operational readiness may be measured. A multiple case study research design was used to investigate the application of information-sharing and collaboration in two distinct Air Force supply chains. Cross-case comparative analysis of the supply chains supporting the PTO shafts on the F-15 engine and the T-38 engine evaluated each supply chain's characteristics and levels of information-sharing and collaboration. The …

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Factors Affecting The Transfer Of Basic Combat Skills Training In The Air Force, Rodney E. Mccraine Mar 2006

Factors Affecting The Transfer Of Basic Combat Skills Training In The Air Force, Rodney E. Mccraine

Theses and Dissertations

During Operations ENDURING FREEDOM (OEF) and IRAQI FREEDOM (OIF), many Airmen in support career fields were deployed to hostile environments like Afghanistan and Iraq. Deployments of this nature are a departure from normal Air Force operations where support personnel are normally far from the front lines of battle. The purpose of this research was to understand the factors that affect the transfer of basic combat skills training from the classroom to the battlefield. Specifically, this thesis sought to answer five research questions addressing the current combat skills training requirements, the perceived training transfer of basic combat skills, the factors that …

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Improving Intercontinental Ballistic Missile Maintenance Scheduling Through The Use Of Location Analysis Methodologies, Dale L. Overholts Ii Mar 2006

Improving Intercontinental Ballistic Missile Maintenance Scheduling Through The Use Of Location Analysis Methodologies, Dale L. Overholts Ii

Theses and Dissertations

The events of September 11, 2001 have led to increased security requirements for all ICBM-related activities. Missile maintenance managers must explore new scheduling techniques to sustain weapon system readiness levels in light of published security enhancements. The problem of improving missile maintenance scheduling is modeled as a two-stage heuristic that utilizes the maximal covering location problem methodology. Maintenance activities are categorized and weighted according to published priority designation and mission impact. The model’s first stage seeks to select two security umbrellas that maximize the weighted sum of maintenance activities. Stage two seeks to determine a maintenance schedule comprised of launch …

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Algebra Of Tankers, Margaret M. Romero Mar 2006

Algebra Of Tankers, Margaret M. Romero

Theses and Dissertations

The Air Force's aerial refueling tanker aircraft provide essential support for deployment and employment of combat and combat support aircraft, by extending their endurance and enhancing fighting efficiency. As the lead command for air refuelers, Air Mobility Command (AMC) must frequently examine the capability of current and proposed tanker fleets to meet mission requirements due to limited tanker resources. Analysts in AMC primarily use the Combined Mating and Ranging Plans System to provide actual tanker/receiver aircraft schedules and flight plans that take into account numerous system constraints. However, this tool can take weeks to run. Even recently developed quick look …

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Discrete Event Simulation Model Of The Ground Maintenance Operations Cycle Of A Reusable Launch Vehicle, John T. Pope Iii Mar 2006

Discrete Event Simulation Model Of The Ground Maintenance Operations Cycle Of A Reusable Launch Vehicle, John T. Pope Iii

Theses and Dissertations

The Air Force uses a family of expendable launch vehicles to meet its spacelift needs. Unfortunately, this method is not responsive: months of preparation are typically required and launch costs are high. Consequently, the Air Force seeks a reusable military launch vehicle that can be launched inexpensively and quickly regenerated between flights. Air Force Research Laboratory personnel desire a tool to help evaluate candidate designs and perform tradeoff studies necessary to acquire a launch vehicle that will achieve Air Force goals. The objective of this research was first to develop a conceptual model of maintenance operations needed to regenerate a …

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Headquarters Air Force Material Command Customer Relationship Study, Damelsa D. White Mar 2006

Headquarters Air Force Material Command Customer Relationship Study, Damelsa D. White

Theses and Dissertations

Because of the lack of product and price differentiation, many organizations consider Customer Relationship Management (CRM) their primary focus. CRM uses information about each customer to make each customer more valuable to the organization, and the organization more valuable to the customer, while decreasing the cost of servicing the customer. However, an organization cannot conform to customer specifications if the needs of the customers as well as what the customer values is not known. As a result, Headquarters (HQ) Air Force Materiel Command (AFMC) is taking the initiative to gain an understanding of their customers. The purpose of this study …

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Access Based Cost Estimation For Beddown Analysis, Jasper E. Pennington Mar 2006

Access Based Cost Estimation For Beddown Analysis, Jasper E. Pennington

Theses and Dissertations

The purpose of this research is to develop an automated web-enabled beddown estimation application for Air Mobility Command in order to increase the effectiveness and enhance the robustness of beddown estimates. This includes generating rough order of magnitude cost estimates for the potential beddown of air mobility assets as well as serving as a centralized data warehouse for current and future scenarios. The application developed is intended to provide the analyst with the maximum amount of both quantitative and qualitative input for any potential decision to quickly identify infrastructure requirement shortfalls and associated costs to satisfy those shortfalls. The application …

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Gauging The Commitment Of Clandestine Group Members, Doneda D. Downs Mar 2006

Gauging The Commitment Of Clandestine Group Members, Doneda D. Downs

Theses and Dissertations

Since the attacks of September 11th, 2001, there has been a great deal of attention given to understanding the inner workings of terrorist organizations in order for the United States to be successful in the Global War on Terrorism. Group dynamics has been one area of interest pursued to gain more insight into a terrorist's cognitive battlespace. Until a few years ago, most research on individual commitment and organizational cohesion has been based primarily on questionnaires and open observations on groups that desire to be understood. However, terrorist organizations are clandestine; they constantly employ operations security (OPSEC) to ensure protection …

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Optimizing Mean Mission Duration For Multiple-Payload Satellites, John A. Flory Mar 2006

Optimizing Mean Mission Duration For Multiple-Payload Satellites, John A. Flory

Theses and Dissertations

This thesis addresses the problem of optimally selecting and specifying satellite payloads for inclusion on a satellite bus to be launched into a constellation. The objective is to select and specify payloads so that the total lifetime utility of the constellation is maximized. The satellite bus is limited by finite power, weight, volume, and cost constraints. This problem is modeled as a classical knapsack problem in one and multiple dimensions, and dynamic programming and binary integer programming formulations are provided to solve the problem. Due to the computational complexity of the problem, the solution techniques include exact methods as well …

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Carrier Lifetime Dynamics Of Epitaxial Layer Hvpe Gallium Arsenide Using Time-Resolved Experiments, Wayne E. Eikenberry Mar 2006

Carrier Lifetime Dynamics Of Epitaxial Layer Hvpe Gallium Arsenide Using Time-Resolved Experiments, Wayne E. Eikenberry

Theses and Dissertations

GaAs is a potential semiconductor material for producing both mid-infrared and terahertz radiation using the new technique of quasi-phase matching in an orientationally patterned GaAs (OP-GaAs) crystal. OP-GaAs is grown using a fast growth process called hydride vapor phase epitaxy (HVPE). Unfortunately, HVPE produces a high number of defects. These defects cause Shockley-Read-Hall recombination rates to dominate over Auger and radiative recombination rates. The carrier lifetime from four OP-GaAs samples are reported here using two different experimental techniques. The first experiment used a streak camera to measure the carrier lifetime via time-resolved photoluminescence. The temporal resolution of the streak camera …

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Macroscopic Computational Model Of Dielectric Barrier Discharge Plasma Actuators, Timothy R. Klein Feb 2006

Macroscopic Computational Model Of Dielectric Barrier Discharge Plasma Actuators, Timothy R. Klein

Theses and Dissertations

Recent progress in the generation and sustainment of gas discharges at atmospheric pressure has energized research in the field of plasma-aerodynamics. Plasma actuators are promising devices that achieve flow control with no moving parts, do not alter the airfoil shape and place no parts in the flow. The operation of a plasma actuator is examined using a macroscopic (force and power addition) computational fluid dynamic model of a dielectric barrier discharge, DBD, in Fluent. A parametric approach is adopted to survey the range of requisite magnitudes of momentum and energy delivered to the flow field and to identify the effects …

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Active Noise Control Of Stageloader Noise In Longwall Mining, Jeremy M. Slagley, Steven Guffey Jan 2006

Active Noise Control Of Stageloader Noise In Longwall Mining, Jeremy M. Slagley, Steven Guffey

Faculty Publications

With the large-scale mechanization inherent to the mining industry, noise-induced hearing loss remains a major concern. As part of on-going efforts to develop engineering controls to reduce noise levels in longwall mining, active noise control experiments were conducted above ground on a modified non-working stageloader. Recorded underground stageloader noise was broadcast into the above ground stageloader. The result was an average 7 dBA reduction when the active noise control was applied. These results suggest the possibility that active noise reduction can be a useful means to reduce stageloader noise if the control system can be made sufficiently rugged. The study …

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