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Attitude Model Of A Reaction Wheel/Fixed Thruster Based Satellite Using Telemetry Data, Jason E. Smith Mar 2005

Attitude Model Of A Reaction Wheel/Fixed Thruster Based Satellite Using Telemetry Data, Jason E. Smith

Theses and Dissertations

Attitude determination of satellites is normally the job of inertial instruments, such as gyroscopes, or through sensing instruments, such as star trackers or Global Positioning Satellites (GPS). Satellite health monitoring systems watch and determine if the satellite deviates from its normal operating attitude orientation. Knowing the orientation of a satellite is essential in being able to control it in order to complete the satellite's designated mission. While there are a multitude of ways to determine a satellite's orientation, very little research has been done on determining if the attitude of a satellite can be determined directly from telemetry data of …

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Feasibility Study Of Variance Reduction In The Thunder Campaign-Level Model, Earl M. Bednar Mar 2005

Feasibility Study Of Variance Reduction In The Thunder Campaign-Level Model, Earl M. Bednar

Theses and Dissertations

As an Air Force Chief of Staff endorsed topic, Air Force Studies and Analyses Agency (AFSAA) requested an effective and efficient way to reduce the variance in analysis results from THUNDER. THUNDER is a large-scale discrete event simulation of campaign-level military operations and is used to examine issues involving the utility and effectiveness of air and space power in a theater-level, joint warfare context. Given the large number of stochastic components within THUNDER, results are produced with highly variable measures of effectiveness (MOEs), causing difficulties in evaluating alternative force structures, weapon systems, etc. This work responds to AFSAA's request by …

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Project Portfolio Management: An Investigation Of One Air Force Product Center, Bryan D. Edmunds Mar 2005

Project Portfolio Management: An Investigation Of One Air Force Product Center, Bryan D. Edmunds

Theses and Dissertations

Over the last two decades, reducing product development times in the DoD has been the focus of many committees, commissions, and research efforts. Despite the implementation of numerous recommendations, the DoD still struggles with long acquisition cycle times. This research is part of the Air Force Cycle Time Reduction Research Program (CTRRP), which grew out of the Cycle Time Reduction Action Plan, developed in 1998. This research focuses on the portfolio management (project selection and resource allocation) part of the CTRRP. The purpose of this research effort was to investigate the use of portfolio management within the Air Force. Specifically, …

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Performance Based Service Acquisition: A Quantitative Evaluation Of Implementation Goals And Performance In The United States Air Force, Dylan D. Pope Mar 2005

Performance Based Service Acquisition: A Quantitative Evaluation Of Implementation Goals And Performance In The United States Air Force, Dylan D. Pope

Theses and Dissertations

In an attempt to maximize cost savings in the rapidly growing services sector, the DoD established a Performance Based Service Acquisition (PBSA) strategy that focuses on evaluating contractor performance based on their ability to meet desired outcomes rather than the means to which the outcomes are obtained. In April 2000, Dr. Gansler, then Under Secretary of Defense for Acquisition, Technology and Logistics, mandated that 50 percent of all eligible service acquisitions be awarded using PBSA methods by FY 2005. Since then very little research has been focused on USAF implementation of PBSA and the progress and attainment of the PBSA …

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Reconstruction Of Chromotomographic Imaging System Infrared Hyperspectral Scenes, Malcolm G. Gould Mar 2005

Reconstruction Of Chromotomographic Imaging System Infrared Hyperspectral Scenes, Malcolm G. Gould

Theses and Dissertations

Hyperspectral imagery providing both spatial and spectral information has diverse applications in remote sensing and scientific imaging scenarios. The development of the Chromotomographic Imaging System (CTIS) allows simultaneous collection of both spatial and spectral data by a two-dimensional (2D) focal plane detector array. Post-processing of the 2D detector data reconstructs the three-dimensional (3D) hyperspectral content of the imaged scene. This thesis develops Estimation Theory based algorithms for reconstructing the hyperspectral scene data. The initial algorithm developed reconstructs the 3D hyperspectral scene data cube. An additional algorithm reconstructs a matrix comprised of one spectral dimension and one compound spatial dimension. This …

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Numerical Analysis And Optimization Of The Ultra Compact Combustors, Roger T. Greenwood Mar 2005

Numerical Analysis And Optimization Of The Ultra Compact Combustors, Roger T. Greenwood

Theses and Dissertations

In an effort to increase thrust per weight ratio and decrease pollutant emissions of aero-turbine jet engines, a circumferentially burning Ultra Compact Combustor (UCC) with a Cavity-in-a-Cavity design has been developed. A numerical analysis of this design has been conducted and compared with experimental results. The CFD model has been validated through a wide range of conditions and four alternative physical configurations of the UCC have been modeled. Emissions, combustor efficiencies, temperature and velocity profiles, and pressure drop values were used as comparison parameters. Numerical results indicate that increasing the outflow area will increase the pressure drop over the combustor …

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Comparing Management Approaches For Automatic Test Systems: A Strategic Missile Case Study, William C. Ford Mar 2005

Comparing Management Approaches For Automatic Test Systems: A Strategic Missile Case Study, William C. Ford

Theses and Dissertations

From 1980 to 1992, the DoD spent over $50 billion acquiring Automatic Test Systems (ATS) used to test weapon systems. At that time, procuring unique ATS to support single weapon systems was the norm. In 1994, the DoD made a dramatic change to their ATS acquisition policy; common ATS that supported multiple weapon systems was preferred over ATS tailored to support a single weapon system. Expected benefits of this new policy included: more reliable equipment, increased supportability, decreased cost, smaller logistics footprint, and decreased manning. To date, the common ATS initiative has garnered little support AF-wide due to lack of …

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Air Force Jp-8 Fuel Distribution System: A Statistical Analysis To Determine Where And When To Sample, Eric J. Heath Mar 2005

Air Force Jp-8 Fuel Distribution System: A Statistical Analysis To Determine Where And When To Sample, Eric J. Heath

Theses and Dissertations

The Air Force Petroleum Office at Wright-Patterson Air Force Base, Ohio collects JP-8 sampling data, but this data doesn't undergo analysis to determine the health of the base-level JP-8 fuel distribution system. Commanders possess no known confidence level when assessing base-level fuel health. Therefore, the objective of this research is to assess Air Force base-level fuel sampling data to determine the base-level sampling point that ensures a quality and healthy product at the aircraft. Also, this research seeks to identify how often correlation sampling should take place. Sample test pass rates are analyzed from three locations, receipt, storage, and vehicles/aircraft, …

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An Evaluation Of Wind Turbine Technology At Peterson Afb, Randy C. Combs Mar 2005

An Evaluation Of Wind Turbine Technology At Peterson Afb, Randy C. Combs

Theses and Dissertations

Wind energy technology is a viable source for attaining the emission reduction and renewable energy use goals set forth by the executive office. In accordance with Executive Orders, the Air Force must reduce greenhouse emissions and energy consumption, and expand the use of renewable energy sources within its facilities nation-wide by year 2010. This mandate requires that the Air Force look at alternative electrical production and rely more on such renewable energy resources as wind power. The specific problem addressed by this research is whether on-site wind energy generation can be more economically feasible than the conventional energy consumption at …

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An Analysis Of The Relationship Between Environmental Management And Environmental Compliance At Marine Corps Installations, Bevin J. Keen Mar 2005

An Analysis Of The Relationship Between Environmental Management And Environmental Compliance At Marine Corps Installations, Bevin J. Keen

Theses and Dissertations

Environmental compliance on military is challenging for a number of reasons, including the complexity of regulations, and the variety of operations which impact the environment. At times, public concerns and penalties stemming from environmental issues has infringed upon the United States Marine Corps' (USMC) ability to use all installation resources without restriction. This thesis examines which facets of environmental management are closely associated with high levels of compliance. Five variables of interest: Total Compliance, Total Management, Audit Management, Policy Management, and Training Management were isolated from 1998-2004 USMC environmental audit data, and subjected to statistical analysis. Through the examination of …

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Decision Analysis Using Value-Focused Thinking To Select Renewable Alternative Fuels, Eric A. Queddeng Mar 2005

Decision Analysis Using Value-Focused Thinking To Select Renewable Alternative Fuels, Eric A. Queddeng

Theses and Dissertations

The United States relies on imported oil as a result of domestic petroleum consumption rates greatly exceeding production rates. Alternative fuels are a major force in the effort to reduce petroleum consumption in the transportation industry. The transportation industry also accounts for 1/3 of all greenhouse gas emissions and nearly half of all cancers attributed to outdoor sources of pollutants. The purpose of this research was to evaluate the economic and environmental feasibility of renewable alternative fuels and associated blends (ethanol, methanol, 100% biodiesel (B100), 20% biodiesel (B20) and e-diesel) compared to non-renewable alternative fuels (compressed natural gas and propane) …

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An Investigation Into Palladium-Catalyzed Reduction Of Perchlorate In Water, Eric G. Barney Mar 2005

An Investigation Into Palladium-Catalyzed Reduction Of Perchlorate In Water, Eric G. Barney

Theses and Dissertations

In this study, application of a catalytic reactor to facilitate chemical reduction of perchlorate was investigated. Palladium-coated pellets were used as the catalyst, and formic acid was used as the reductant. Reactor performance was evaluated under a variety of operating conditions (influent pH, reductant concentration, residence time). Very little perchlorate reduction was observed under any operating condition. At best, approximately 8% perchlorate reduction was observed. This small reduction efficiency is clearly not sufficient for environmental treatment applications. Perchlorate strongly adsorbed to the catalyst at low pH (3 - 3.3). At higher pH (4 - 10), little adsorption was observed. This …

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Validation Of An Innovative Groundwater Contaminant Flux Measurement Method, Seh J. Kim Mar 2005

Validation Of An Innovative Groundwater Contaminant Flux Measurement Method, Seh J. Kim

Theses and Dissertations

The ability to measure groundwater contaminant flux is increasingly being recognized as crucial in order to prioritize contaminated site cleanups, estimate the efficiency of remediation technologies, measure rates of natural attenuation, and apply proper source terms to model groundwater contaminant transport. An innovative mass flux measurement method using horizontal flow treatment wells (HFTWs) was developed recently to compensate for the disadvantages of other flux measurement methods that are being used. Flux measurement methods can be categorized as either point methods or integral methods. As the name suggests, point methods measure flux at a specific point or points in the subsurface. …

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Removal Of Cyclohexane From A Contaminated Air Stream Using A Dense Phase Membrane Bioreactor, Michael G. Roberts Mar 2005

Removal Of Cyclohexane From A Contaminated Air Stream Using A Dense Phase Membrane Bioreactor, Michael G. Roberts

Theses and Dissertations

The purpose of this research was to determine the ability of a dense phase membrane bioreactor to remove cyclohexane, a volatile organic compound in JP-8 jet fuel, from a contaminated air stream using a biologically active film for degradation. The research answered questions regarding applications of membrane bioreactors, the ability of cyclohexane to diffuse through a dense phase membrane, growth of a viable microbial culture, and determination of the performance capabilities of the reactor. To answer these questions, a literature review was conducted and laboratory experiments were performed. Through the design, construction, and testing of the dense phase membrane bioreactor …

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Evaluation Of Fuel Oxygenate Degradation In The Vadose Zone, David A. Torres Mar 2005

Evaluation Of Fuel Oxygenate Degradation In The Vadose Zone, David A. Torres

Theses and Dissertations

Groundwater contamination by petroleum products poses a potential human health and safety risk. Methyl tert-butyl ether (MTBE) was a commonly used fuel oxygenate that was added to gasoline to meet environmental regulations. The widespread use of MTBE resulted in significant contamination of drinking water supplies across the United States. This research evaluated the degradation characteristics of potential alternative fuel oxygenates in the vadose zone. One fuel oxygenate being considered as an alternative to MTBE is diisopropyl ether (DIPE). Specifically, this thesis sought to answer three research questions: what is the potential for DIPE degradation in soil without prior microbial augmentation, …

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An Analysis Of Biometric Technology As An Enabler To Information Assurance, Darren A. Deschaine Mar 2005

An Analysis Of Biometric Technology As An Enabler To Information Assurance, Darren A. Deschaine

Theses and Dissertations

The use of and dependence on, Information technology (IT) has grown tremendously in the last two decades. Still, some believe the United States is only in the infancy of this growth. This explosive growth has opened the door to capabilities that were only dreamed of in the past. As easy as it is to see how advantageous this technology is, it also is clear that with its advantages come distinct responsibilities and new problems that must be addressed. For instance, the minute one begins using information processing systems, the world of information assurance (IA) becomes far more complex. As a …

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A Historical Context Analysis Of Changes In Content Management Ideology, William Lee Jr. Mar 2005

A Historical Context Analysis Of Changes In Content Management Ideology, William Lee Jr.

Theses and Dissertations

Digital content has grown continually over the past years, yet acceptance of a common definition of what is "content management" still generates debates in IS communities. This research will be a qualitative study using a combined approach of historical and context analysis of literary artifacts for drawing inferences to explore the evolutionary changes in content management ideology. Using a seven-step process, a specific structure is designed with a systematic approach to encounter the phenomena being researched and present the evidence of the results. Performing an analysis on the evolution of content management from a historical perspective will benefit researchers and …

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A Study To Determine Damage Assessment Methods Or Models On Air Force Networks, Lisa S. Thiem Mar 2005

A Study To Determine Damage Assessment Methods Or Models On Air Force Networks, Lisa S. Thiem

Theses and Dissertations

Damage assessment for computer networks is a new area of interest for the Air Force. Previously, there has not been a concerted effort to codify damage assessment or develop a model that can be applied in assessing damage done by criminals, natural disasters, or other methods of damaging a computer network. The research undertaken attempts to identify if the Air Force MAJCOM Network Operations Support Centers (NOSC) use damage assessment models or methods. If the Air Force does use a model or method, an additional question of how the model was attained or decided upon is asked. All information comes …

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Assessing The Usefulness Of Visualization Tools To Investigate Hidden Patterns With Insider Attack Cases, Amy M. Rammel Mar 2005

Assessing The Usefulness Of Visualization Tools To Investigate Hidden Patterns With Insider Attack Cases, Amy M. Rammel

Theses and Dissertations

The insider threat is a major concern for organizations. Open markets, technological advances, and the evolving definition of employee have exacerbated the insider threat. Insider threat research efforts are focusing on both prevention and detection techniques. However, recent security violation trends highlight the damage insider attacks cause organizations and illuminate why organizations and researchers must develop new approaches to this challenge. Although fruitful research is being conducted and new technologies are being applied to the insider threat problem, companies remain susceptible to the costly damage generated by insider threat actions. This research explored how visualization tools may be useful in …

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An Eleven Year Retrospective Of The Acquisition Review Journal, Mitchell J. Elder Mar 2005

An Eleven Year Retrospective Of The Acquisition Review Journal, Mitchell J. Elder

Theses and Dissertations

The purpose of this research was to examine the evolution of the Acquisition Review Journal (ARJ) through its first 11 years of publication. Researchers assessed the Defense Acquisition community through a review of ARJ articles. They considered what areas academics and practitioners have explored, and how they have explored them. This review documents such characteristics as areas of study, methods of study, and contributors. Trends are identified and conclusions are drawn as to the contribution of the ARJ to the Defense Acquisition community of practice.

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The Feasibility Of The U.S. Air Force Mandating The Exclusive Use And Purchase Of Forest Stewardship Council Certified Wood And Paper Containing 100% Post Consumer Content, Silinda Johnson Mar 2005

The Feasibility Of The U.S. Air Force Mandating The Exclusive Use And Purchase Of Forest Stewardship Council Certified Wood And Paper Containing 100% Post Consumer Content, Silinda Johnson

Theses and Dissertations

The Resource Conservation and Recovery Act required federal agencies to purchase products with the highest recovered content (or post-consumer content in the case of paper) as practicable. The Office of Federal Procurement Policy required all executive agencies to give preference in their procurement programs to products that conserve natural resources and protect the environment. These requirements necessitate that the Air Force consider purchasing 100% post-consumer content (PCC) paper and Forest Stewardship Council (FSC) certified wood because of their environmentally preferable attributes. This study compared the availability, performance standards, and prices of 100% PCC paper to 30% PCC paper and FSC-certified …

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The Use Of X-Ray Pulsars For Aiding Gps Satellite Orbit Determination, Dennis W. Woodfork Ii Mar 2005

The Use Of X-Ray Pulsars For Aiding Gps Satellite Orbit Determination, Dennis W. Woodfork Ii

Theses and Dissertations

This research proposes the use of an existing "signal of opportunity" - namely x-ray pulsars - to improve the accuracy and robustness of the GPS satellite and clock estimation algorithm. Improvement in satellite and clock accuracy results in a direct benefit to the user. A simulation has been developed to determine the effects of using x-ray pulsar measurements on the GPS Operational Control Segment. The epoch-specific position, velocity, and clock errors of all GPS satellites in the constellation were estimated using both pseudoranges and time-difference-of-arrival (TDOA) measurements from pulsars. The primary measure of accuracy is a constellation Signal-In-Space Range Error …

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Detection Of Bacillus Spores By Aptamer Selectivity Using Atomic Force Microscopy, Nina M. Houtkooper Mar 2005

Detection Of Bacillus Spores By Aptamer Selectivity Using Atomic Force Microscopy, Nina M. Houtkooper

Theses and Dissertations

The anthrax attack of Oct 2001 demonstrates the need for a rapid detector for spores of Bacillus anthracis (BA). Current technology requires cultures of BA to be grown for 24 hours. Using aptamers, a type of nucleic acid ligand selective for a target molecule, to select BA spores for measurement without culturing is a possible solution for quicker detection. An aptamer having a specially selected structure is expected to selectively bind to the surface of its target spore, separating it from other material. An atomic force microscopy (AFM) method was developed to test this selectivity. Aptamers having structure selected to …

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Examining The Impact Of Quality Assurance Manning Practices In Usaf Aircraft Maintenance Units, Terry D. Moore Mar 2005

Examining The Impact Of Quality Assurance Manning Practices In Usaf Aircraft Maintenance Units, Terry D. Moore

Theses and Dissertations

The purpose of this research was to examine the impact that current USAF Quality Assurance (QA) manning practices has on key aircraft wing- and unit-level metrics. Interviews and surveys culminated in development of a QA Manning Effectiveness Matrix. We then used the matrix to calculate historical QA manning effectiveness at 16 ACC bases. Effectiveness scores were regressed with associated historical data for 26 metrics derived from a Delphi survey. Nine metrics were deemed statistically significant, including break rates, cannibalization rates, flying schedule effectiveness rates, key task list pass rates, maintenance scheduling effectiveness rates, quality verification inspection pass rates, repeat rates, …

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Using Depot Inventory Position To Determine Transportation Mode Of Retrograde Reparable Assets, Edward C. Snow Jr. Mar 2005

Using Depot Inventory Position To Determine Transportation Mode Of Retrograde Reparable Assets, Edward C. Snow Jr.

Theses and Dissertations

Air Force logistics policies direct the "expedited evacuation of repairables to the source of repair", in an effort to allow smaller inventories. Transportation Mode selection is based only on the asset itself. This focus works well when shipping assets out from the depot to a base. When a base ships an asset back to the depot however, the priority of the asset may not be the best way to select the transportation mode. The quantity of the assets at the depot may indicate that fast transportation is unnecessary. The depot may already have enough serviceable assets to meet demand or …

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Advanced Academic Degree Inventory Management (Aadim) Model, Andrew D. Jastrzembski Mar 2005

Advanced Academic Degree Inventory Management (Aadim) Model, Andrew D. Jastrzembski

Theses and Dissertations

This research develops the Advanced Academic Degree (AAD) Inventory Model (AADIM) to employ an inventory management approach to select, educate, and assign officers to duties that require incumbents possessing advanced education in specialized technical disciplines. The AADIM offers an alternative approach to the US Air Force's current billet-based Graduate Education Management System (GEMS). The entry model (AADIM-E) generates, via user inputs, a career field specific advanced education profile and then employs a Markov model to forecast the educational quotas necessary to achieve the desired profile within a prescribed period of time. The utilization model (AADIMU) uses an additive multi-attribute value …

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Selection And Application Of Distorted Risk Measures, Edwin J. Offutt Mar 2005

Selection And Application Of Distorted Risk Measures, Edwin J. Offutt

Theses and Dissertations

This thesis develops and illustrates a methodology for the selection of probability distributions and distortion functions associated with risk scenarios resulting from military capability shortfalls. Distorted (or transformed) risk measures are analyzed and applied to account for loss scenarios that may occur with low frequency but result in catastrophic outcomes. After reviewing the rudimentary concepts of distortion, four well-known continuous distributions, suitable for modeling risk scenarios, are chosen using defined criteria. Based on subject matter expert inputs, a simple method for assigning exactly one of the four distributions to any risk scenario is proposed. Four parametric distortion functions from the …

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Optimal Sampling Of A Chemical Hazard Area, Jennifer R. Plourde Mar 2005

Optimal Sampling Of A Chemical Hazard Area, Jennifer R. Plourde

Theses and Dissertations

This thesis proposes a methodology for optimally sampling a chemical hazard area subsequent to a chemical weapons attack. The objective is to identify the maximum number of areas that no longer require protective gear for safe operations. We model the area as an undirected graph and employ network analysis techniques to provide a methodological framework for identifying an optimal sampling sequence within a fixed time limit. We propose four models that characterize the secondary vapor concentrations: i) static and deterministic, ii) static and stochastic, iii) dynamic and deterministic, and iv) dynamic and stochastic. Comparisons of the static cases and their …

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Investigating The Complexities Of Nation-Building: A Sub-National Regional Perspective, Matthew J. Robbins Mar 2005

Investigating The Complexities Of Nation-Building: A Sub-National Regional Perspective, Matthew J. Robbins

Theses and Dissertations

Stabilization and reconstruction operations are necessary to secure and maintain the peace in the aftermath of conflict. The complexities of nation-building involve many different but interrelated systems and institutions. The basic structure of a country may or may not remain; its political, economic, and judicial systems, cultural, educational, medical, and military institutions, and critical infrastructure all vitally contribute to the overall progression of stability and prosperity. Understanding the significance of the dynamic relationships between the forces in play during stability and reconstruction operations is paramount to the successful conclusion of such missions. The system dynamics model proposed in this research …

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A Qualitative Study Of Industry And Air Force Commodity Council Processes, Robert J. Irvine Mar 2005

A Qualitative Study Of Industry And Air Force Commodity Council Processes, Robert J. Irvine

Theses and Dissertations

The purpose of this research was to compare industry and Air Force commodity council processes. More specifically, this research used a survey to gather strategic sourcing philosophies and procedures (with respect to small business participation in procurement strategies) from successful industry firms. Industry source selection documentation, applicable government contracting guidelines, and a literature review of strategic sourcing materials were also reviewed. The current Air Force commodity council process and associated historical documents were then studied using a business process modeling tool. It was determined that the Air Force process differs from industry in how small business participation is addressed, the …

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