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Air Force Institute of Technology

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Performance Enhancements Of Ranging Radio Aided Navigation, Patric J. Ernsberger Mar 2009

Performance Enhancements Of Ranging Radio Aided Navigation, Patric J. Ernsberger

Theses and Dissertations

Determining the position of team members is always useful information, whether it is a team of firefighters fighting a blaze or combatants clearing a building in the field. This information becomes even more decisive for the people responsible for their safety. To accomplish this in areas denied Global Navigation Satellite System (GNSS), such as around buildings or in steep valleys, alternative methods must be used. Radio ranging systems have been a part of the navigation solution for years. They unfortunately have poor performance in certain areas, such as inside buildings, due to multipath and other errors. To improve the position …

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A Taxonomy For And Analysis Of Anonymous Communications Networks, Douglas J. Kelly Mar 2009

A Taxonomy For And Analysis Of Anonymous Communications Networks, Douglas J. Kelly

Theses and Dissertations

Any entity operating in cyberspace is susceptible to debilitating attacks. With cyber attacks intended to gather intelligence and disrupt communications rapidly replacing the threat of conventional and nuclear attacks, a new age of warfare is at hand. In 2003, the United States acknowledged that the speed and anonymity of cyber attacks makes distinguishing among the actions of terrorists, criminals, and nation states difficult. Even President Obama’s Cybersecurity Chief-elect recognizes the challenge of increasingly sophisticated cyber attacks. Now through April 2009, the White House is reviewing federal cyber initiatives to protect US citizen privacy rights. Indeed, the rising quantity and ubiquity …

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An Evaluation Of Solar Air Heating At United States Air Force Installations, David S. Brown Mar 2009

An Evaluation Of Solar Air Heating At United States Air Force Installations, David S. Brown

Theses and Dissertations

The purpose of this research was to evaluate the use of solar air heating at U.S. Air Force installations. Specifically, this thesis analyzed Unglazed Transpired Collector (UTC) technology, more commonly known as SolarWalls®. This thesis sought to determine if UTC systems are an economically and environmentally viable technology which Air Force energy managers should include in their portfolio of alternative energy options. This research question was answered through the use of case studies and life-cycle cost analysis. Case studies were performed at various U.S. military installations which have already utilized UTC systems to provide a consolidated source of lessons learned. …

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A 4-Step Process Evaluation Model To Assess The Success Of Performance Based Logistics Contracts, Ferit Buyukgural Mar 2009

A 4-Step Process Evaluation Model To Assess The Success Of Performance Based Logistics Contracts, Ferit Buyukgural

Theses and Dissertations

Performance-Based Logistics (PBL) is DoD' s preferred product support approach in order to satisfy vitally-important war fighter needs. The elasticity of these needs makes it impossible to build a one-fits-all template PBL contract with the contractors. Thus, both economic metrics such as Cost per Unit Usage and non-economic metrics such as Availability, Reliability, Logistics Foot Print and Logistics Response Time can be defined and tailored according to each individual program. However, evaluation of the success of a PBL contract gets harder proportional to the increased number of different types of metrics. This research suggests an integrated model approach for combining …

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An Engineering Trade Space Analysis For A Space-Based Hyperspectral Chromotomographic Scanner, Phillip Sheirich Mar 2009

An Engineering Trade Space Analysis For A Space-Based Hyperspectral Chromotomographic Scanner, Phillip Sheirich

Theses and Dissertations

Hyperspectroscopy for fast transient events such as battlefield explosions is an undeveloped area of spectral imaging. This thesis is a discussion of issues involved with taking a laboratory design for a rotating prism hyperspectral chromotomographic (CT) instrument and producing a first approximation satellite payload design, operating scheme and trade space analysis to support demonstration of this technology in low-earth orbit. This instrument promises the capability of adding a time dimension to the normal spatial and spectral data produced by most hyperspectral imagers. The ultimate goal is to conduct experiments demonstrating the ultimate viability of spectral definition of transient combustion events …

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Suite Of Standards For Electromagnetic Material Characterization Using Mode Matching Theory, Brian J. Witthoeft Mar 2009

Suite Of Standards For Electromagnetic Material Characterization Using Mode Matching Theory, Brian J. Witthoeft

Theses and Dissertations

The objective of this research is to determine if an acceptable standard can be developed to access the accuracy and precision of measurements taken using waveguide systems. Tiny changes in material fabrication, processing, and environment can cause problems with accuracy and precision in measurement. There is a great deal of research on uncertainty analysis in the literature. A large portion of the effort will be to determine the levels of uncertainty caused by each of the dimensions of the waveguide insert and to develop a suitable standard capable of verifying system performance. The Mode-Matching Technique will be used to extract …

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Blind Deconvolution Through Polarization Diversity Of Long Exposure Imagery, Steven P. James Mar 2009

Blind Deconvolution Through Polarization Diversity Of Long Exposure Imagery, Steven P. James

Theses and Dissertations

The purpose of the algorithm developed in this thesis was to create a post processing method that could resolve objects at low signal levels using polarization diversity and no knowledge of the atmospheric seeing conditions. The process uses a two-channel system, one unpolarized image and one linearly polarized image, in a GEM algorithm to reconstruct the object. Previous work done by Strong showed that a two-channel system using polarization diversity on short exposure imagery could produce images up to twice the diffraction limit. In this research, long exposure images were simulated and a simple Kolmogorov model used. This allowed for …

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Range Estimation Algorithm Comparison In 3-D Flash Ladar Data, Steven P. Jordan Mar 2009

Range Estimation Algorithm Comparison In 3-D Flash Ladar Data, Steven P. Jordan

Theses and Dissertations

Range estimation algorithms have been applied to Laser Detection and Ranging (LADAR) data to test for accuracy and precision. Data was acquired from Matlab® simulations and an experiment using the Advanced Scientific Concepts 3-D flash LADAR camera. Simulated LADAR data was based on a Gaussian pulse shape model with Poisson noise added. Simulations were performed to test range estimation algorithm performance with respect to waveform position within the range gate. The effectiveness of each algorithm is presented in terms of its average root mean square error and standard deviation in 1000 trials. The measured data experiment examined the effectiveness of …

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Modeling Of Aircraft Deicing Fluid Induced Biochemical Oxygen Demand In Subsurface-Flow Constructed Treatment Wetlands, William J. Mclaughlin Mar 2009

Modeling Of Aircraft Deicing Fluid Induced Biochemical Oxygen Demand In Subsurface-Flow Constructed Treatment Wetlands, William J. Mclaughlin

Theses and Dissertations

Aircraft deicing is vital to safe operation in cold weather environments. Unfortunately, release of glycol-based aircraft deicing fluids (ADF) to waterways adjacent to airfields poses a significant environmental threat. The deicing fluids used at DoD airfields impart a high biochemical oxygen demand (BOD) when they enter waterways. The currently accepted conventional treatment is collection and transport of ADF-laden storm water to a publicly owned treatment works. The volume and BOD concentrations in the storm water often make this type of treatment impractical. Subsurface flow constructed treatment wetlands have been demonstrated to be effective in attenuating ADF-induced BOD. The models currently …

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Classification Of Schedule Management Barriers Through Concept Mapping, Gregory W. Voth Mar 2009

Classification Of Schedule Management Barriers Through Concept Mapping, Gregory W. Voth

Theses and Dissertations

Barriers to adoption of schedule management processes are a matter of serious concern to the acquisition community. Schedule management has been widely accepted to contribute to the successful execution of complicated system development processes since the 1950s. However, studies of recent acquisition failures illustrate that over the last 15 years, there has been significant internal resistance to the adoption of schedule management processes. This exploratory effort used concept mapping to identify and classify the types of barriers existing in the Aeronautical Systems Center (ASC). A series of open-ended questions were posed to four experienced program managers in ASC. Units of …

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Near Real-Time Closed-Loop Optimal Control Feedback For Spacecraft Attitude Maneuvers, C. Douglas Mcfarland Mar 2009

Near Real-Time Closed-Loop Optimal Control Feedback For Spacecraft Attitude Maneuvers, C. Douglas Mcfarland

Theses and Dissertations

Optimization of spacecraft attitude maneuvers can significantly reduce attitude control system size and mass, and extend satellite end-of-life. Optimal control theory has been applied to solve a variety of open-loop optimal control problems for terrestrial, air, and space applications. However, general application of real-time optimal controllers on spacecraft for large slew maneuvers has been limited because open-loop control systems are inherently vulnerable to error and the computation necessary to solve for an optimized control solution is resource intensive. This research effort is focused on developing a near real-time optimal control (RTOC) system for spacecraft attitude maneuvers on the Air Force …

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Vision-Aided Cooperative Navigation For Multiple Unmanned Vehicles, Jason K. Bingham Mar 2009

Vision-Aided Cooperative Navigation For Multiple Unmanned Vehicles, Jason K. Bingham

Theses and Dissertations

In the recent past, a shift has taken place from manned to unmanned Intelligence, Surveillance, and Reconnaissance (ISR) missions. This shift has lead to an increase in the number of unmanned vehicles (UV) operating in a theater. Additionally, removal of the crew allows for a reduction in vehicle scale, which leads to an increased ability to operate in GPS degraded environments. With the loss of GPS signals the vehicles must rely on Inertial Navigation Systems (INS) which when reduced to an appropriate size are inherently inaccurate. This research endeavors to exploit three attributes of increased UV use for ISR missions. …

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Developing A Tool For The Location Optimization Of The Alert Aircraft With Changing Threat Anticipation, Okan Arslan Mar 2009

Developing A Tool For The Location Optimization Of The Alert Aircraft With Changing Threat Anticipation, Okan Arslan

Theses and Dissertations

The threat to the airspace is posed by the outside world in conventional terms as well as hostilities from within the airspace such as hijacked aircraft. Alert aircraft are located with the sole responsibility of responding to any incident. Different regions of the airspace may have different alert states depending on current intelligence input. Due to non-constant states of threat level, the Turkish Air Force must deploy aircraft to cover the more sensitive regions with a greater number of aircraft with a relatively short response time. This research deals with the problem by developing a tool for the location optimization …

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Mitigating Insider Sabotage And Espionage: A Review Of The United States Air Force's Current Posture, Erika C. Leach Mar 2009

Mitigating Insider Sabotage And Espionage: A Review Of The United States Air Force's Current Posture, Erika C. Leach

Theses and Dissertations

The security threat from malicious insiders affects all organizations. Mitigating this problem is quite difficult due to the fact that (1) there is no definitive profile for malicious insiders, (2) organizations have placed trust in these individuals, and (3) insiders have a vast knowledge of their organization’s personnel, security policies, and information systems. The purpose of this research is to analyze to what extent the United States Air Force (USAF) security policies address the insider threat problem. The policies are reviewed in terms of how well they align with best practices published by the Carnegie Mellon University Computer Emergency Readiness …

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Detecting Near-Earth Objects Using Cross-Correlation With A Point Spread Function, Anthony P. O'Dell Mar 2009

Detecting Near-Earth Objects Using Cross-Correlation With A Point Spread Function, Anthony P. O'Dell

Theses and Dissertations

This thesis describes a process to help discover Near-Earth Objects (NEOs) of larger than 140 meters in diameter from ground based telescopes. The process involves using Nyquist sampling rate to take data from a ground-based telescope and measuring the atmospheric seeing parameter, r0, at the time of data collection. r0 is then used to create a point spread function (PSF) for a NEO at the visual magnitude limit of the telescope and exposure time. This PSF is cross-correlated with the Nyquist sampling rate image from the telescope to reduce the noise and therefore increase the detection probability of …

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Centralized Cooperative Control For Route Surveillance With Constant Communication, Joseph D. Rosal Mar 2009

Centralized Cooperative Control For Route Surveillance With Constant Communication, Joseph D. Rosal

Theses and Dissertations

The route surveillance mission is a new application of unmanned aircraft systems (UASs) to meet the reconnaissance and surveillance requirements of combatant commanders. The new mission intends to field a UAS consisting of unmanned aerial vehicles (UAVs) that can provide day and night surveillance of convoy routes. This research focuses on developing a solution strategy for the mission based on the application of optimal control and cooperative control theory. The route surveillance controller uses the UAS team size to divide the route into individual sectors for each entity. A specifically designed cost function and path constraints are used to formulate …

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Operations-Focused Optimized Theater Weather Sensing Strategies Using Preemptive Binary Integer Programming, Andrew J. Geyer Mar 2009

Operations-Focused Optimized Theater Weather Sensing Strategies Using Preemptive Binary Integer Programming, Andrew J. Geyer

Theses and Dissertations

This thesis describes a method that optimally deploys weather sensors of all types in a battlefield environment. Gridded climatology models are used to determine an estimate for the weighted frequency of occurrence of operationally significant inclement weather events. That data is used to formulate a series of preemptive Binary Integer Linear Programs that maximize detection of expected operationally significant inclement weather occurrences within the constraints of feasibility of sensor deployment, sensor operational lifespan and the sensor’s ability to detect the operationally significant inclement weather elements. The preemptive Binary Integer Linear Programs are combined into a single objective function that maintains …

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Application Of Reliability And Linear Regression To Enterprise Architecture In Support Of The Us Air Force's Capability Review And Risk Assessment, Peter C. Mastro, Richard L. Orcutt Mar 2009

Application Of Reliability And Linear Regression To Enterprise Architecture In Support Of The Us Air Force's Capability Review And Risk Assessment, Peter C. Mastro, Richard L. Orcutt

Theses and Dissertations

This research explored the use of modeling and enterprise architecture in the analysis of Air Force Capabilities. The Air Force accomplishes this through the Capability Review and Risk Assessment (CRRA). The CRRA is currently performed by building architectures which contain Process Sequence Models (PSMs). PSMs are scored by Subject Matter Experts to determine the probability of successfully completing the mission they model and ultimately to determine the risk associated to Air Force capabilities. Two findings were identified. The first is that creating additional architectural viewpoints, some of which are currently being proposed for version 2.0 of the DoD Architecture Framework, …

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Evaluation Of An Innovative Technology For Treatment Of Water Contaminated With Perchlorate And Organic Compunds, Maureen A. Downen Mar 2009

Evaluation Of An Innovative Technology For Treatment Of Water Contaminated With Perchlorate And Organic Compunds, Maureen A. Downen

Theses and Dissertations

Drinking water sources contaminated with both perchlorate and organic compounds have frequently been found in the U.S. Tailored granular activated carbon (T-GAC) is an innovative technology that is being evaluated to determine if it can more cost effectively remove perchlorate than conventional technologies. A question that has been raised is whether T-GAC can economically treat perchlorate-contaminated water that also has organic co-contaminants present. During a field study, trichloroethylene, an organic compound, and perchlorate were successfully removed by adsorption using a T-GAC/GAC system. These results motivated development of a model that could be applied to predict the cost and performance of …

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An Investigation Of Shock Wave Physics Via Hybrid Cfd-Bgk Solution Methods For Nonequilibrium Flows, Brook I. Bentley Mar 2009

An Investigation Of Shock Wave Physics Via Hybrid Cfd-Bgk Solution Methods For Nonequilibrium Flows, Brook I. Bentley

Theses and Dissertations

The Unified Flow Solver, a hybrid continuum-rarefied code, is used to investigate the internal structure of a normal shock wave for a Mach range of 1.55 to 9.0 for Argon, and 1.53 to 3.8 for diatomic Nitrogen. Reciprocal shock thickness, density, temperature, heat flux, and the velocity distribution function are calculated for a one-dimensional shock wave and compared with experimental data from Alsmeyer and DSMC results from Bird. Using the Euler, Navier-Stokes, BGK model, and Three-Temperature BGK model schemes, results from UFS compare well with experiment and DSMC. The Euler scheme shows atypical results, possibly resulting from modifications made to …

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Development Of Non-Uniform Radiation Solution Methods For Atmospheric Re-Entry Using Detailed Thermal Modeling, Jeffrey R. Komives Mar 2009

Development Of Non-Uniform Radiation Solution Methods For Atmospheric Re-Entry Using Detailed Thermal Modeling, Jeffrey R. Komives

Theses and Dissertations

The line-by-line accurate spectral radiation solver SPRADIAN was integrated with the multi-temperature hypersonic flow-solver NH7Air for the purpose of predicting the radiation incident on the surface of a hypersonic re-entry vehicle. Atomic and molecular radiation mechanisms are considered for chemical species present in an Earth atmosphere re-entry. A new numerical method of radiation propagation is presented that is capable of accurately predicting the radiation propagation through a non-uniform radiation field. This method also introduces a unique treatment of the internal energy of each chemical species, independently tracking the vibrational temperatures of all molecular species. The new radiation propagation method is …

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Using Covert Means To Establish Cybercraft Command And Control, Bradley D. Sevy Mar 2009

Using Covert Means To Establish Cybercraft Command And Control, Bradley D. Sevy

Theses and Dissertations

With the increase in speed and availability of computers, our nation's computer and information systems are being attacked with increased sophistication. The Air Force Research Laboratory (AFRL) Information Directorate (RI) is researching a next generation network defense architecture, called Cybercraft, that provides automated and trusted cyber defense capabilities for AF network assets. This research we consider the issues to protect or obfuscate command and control aspects of Cybercraft. In particular, we present a methodology to hide aspects of Cybercraft platform initialization in context to formation of hierarchical, peer-to-peer groups that collectively form the Cybercraft network. Because malicious code networks (known …

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Least-Squares Finite Element Formulation For Fluid-Structure Interaction, Cody C. Rasmussen Mar 2009

Least-Squares Finite Element Formulation For Fluid-Structure Interaction, Cody C. Rasmussen

Theses and Dissertations

Fluid-structure interaction problems prove difficult due to the coupling between fluid and solid behavior. Typically, different theoretical formulations and numerical methods are used to solve fluid and structural problems separately. The least-squares finite element method is capable of accurately solving both fluid and structural problems. This capability allows for a simultaneously coupled fluid structure interaction formulation using a single variational approach to solve complex and nonlinear aeroelasticity problems. The least-squares finite element method was compared to commonly used methods for both structures and fluids individually. The fluid analysis was compared to finite differencing methods and the structural analysis type compared …

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Cooperative Unmanned Aerial Surveillance Control System Architecture, Theodore T. Diamond, Adam L. Rutherford, Jonathan B. Taylor Mar 2009

Cooperative Unmanned Aerial Surveillance Control System Architecture, Theodore T. Diamond, Adam L. Rutherford, Jonathan B. Taylor

Theses and Dissertations

Intelligence, surveillance and reconnaissance (ISR) is a high-demand Department of Defense mission performed by unmanned aircraft systems (UASs) at the tactical and theater levels. Coordinating UASs through cooperative control offers the advantages of persistence, distributed and adaptable sensor coverage, and reduced revisit time on points of interest. The purpose of this thesis is to apply systems engineering principles to the problem of developing a flexible, common control system for cooperative UAS surveillance at the tactical level. The AFIT team developed a concept of operations (CONOPS) encompassing various users and surveillance tasks. The team then used the scenarios in the CONOPS …

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Jet Fuel Hedging Strategies For The Department Of Defense Through Use Of Financial Derivatives, William T. Gibson Mar 2009

Jet Fuel Hedging Strategies For The Department Of Defense Through Use Of Financial Derivatives, William T. Gibson

Theses and Dissertations

The primary purpose of this research is to assess the practicality of utilizing some of the financial derivative products available on the market today in an effort to mitigate monetary losses due to the increasing price of jet fuel, thereby increasing stability in the DOD budget. The scope of this research will focus on the use of futures and call option contracts. Domestic jet fuel expenditure data was collected for Fiscal Years 1996 to 2007 and cross-referenced with the contract process of the previously mentioned financial hedging instruments during the same period of time. Results from the ex post facto …

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Deeply-Integrated Feature Tracking For Embedded Navigation, Jeffery R. Gray Mar 2009

Deeply-Integrated Feature Tracking For Embedded Navigation, Jeffery R. Gray

Theses and Dissertations

The Air Force Institute of Technology (AFIT) is investigating techniques to improve aircraft navigation using low-cost imaging and inertial sensors. Stationary features tracked within the image are used to improve the inertial navigation estimate. These features are tracked using a correspondence search between frames. Previous research investigated aiding these correspondence searches using inertial measurements (i.e., stochastic projection). While this research demonstrated the benefits of further sensor integration, it still relied on robust feature descriptors (e.g., SIFT or SURF) to obtain a reliable correspondence match in the presence of rotation and scale changes. Unfortunately, these robust feature extraction algorithms are computationally …

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Waypoint Generation Based On Sensor Aimpoint, Shannon M. Farrell Mar 2009

Waypoint Generation Based On Sensor Aimpoint, Shannon M. Farrell

Theses and Dissertations

Secretary of Defense Robert M. Gates has emphasized a need for a greater number of intelligence, surveillance, and reconnaissance (ISR) assets to support combatant commanders and military operations globally. Unmanned systems, especially MAVs, used as ISR platforms provide the ability to maintain covertness during missions and help reduce the risk to human life. This research develops waypoint generation algorithms required to keep a point of interest (POI) in the field of view (FOV) of a fixed sensor on a micro air vehicle (MAV) in the presence of a constant wind.
Fixed sensors, while cheaper and less prone to mechanical failure …

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Fusion Of Inertial Sensors And Orthogonal Frequency Division Multiplexed (Ofdm) Signals Of Opportunity For Unassisted Navigation, Jason G. Crosby Mar 2009

Fusion Of Inertial Sensors And Orthogonal Frequency Division Multiplexed (Ofdm) Signals Of Opportunity For Unassisted Navigation, Jason G. Crosby

Theses and Dissertations

The advent of the global positioning system (GPS) has provided worldwide high-accuracy position measurements. However, GPS may be rendered unavailable by jamming, disruption of satellites, or simply by signal shadowing in urban environments. Thus, this thesis considers fusion of Inertial Navigation Systems (INS) and Orthogonal Frequency Division Multiplexed (OFDM) signals of opportunity (SOOP) for navigation. Typical signal of opportunity navigation involves the use of a reference receiver and uses time difference of arrival (TDOA) measurements. However, by exploiting the block structure of OFDM communication signals, the need for the reference receiver is reduced or possibly removed entirely. This research uses …

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Evaluation Of An Opnet Model For Unmanned Aerial Vehicle Networks, Clifton M. Durham Mar 2009

Evaluation Of An Opnet Model For Unmanned Aerial Vehicle Networks, Clifton M. Durham

Theses and Dissertations

The concept of Unmanned Aerial Vehicles (UAVs) was first used as early as the American Civil War, when the North and the South unsuccessfully attempted to launch balloons with explosive devices. Since the American Civil War, the UAV concept has been used in all subsequent military operations. Over the last few years, there has been an explosion in the use of UAVs in military operations, as well as civilian and commercial applications. UAV Mobile Ad Hoc Networks (MANETs) are fast becoming essential to conducting Network-Centric Warfare (NCW). As of October 2006, coalition UAVs, exclusive of hand-launched systems, had flown almost …

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An Assessment Of The Air Force Weather Agency's Readiness For Knowledge Management Initiatives, Daniel Tucker Mar 2009

An Assessment Of The Air Force Weather Agency's Readiness For Knowledge Management Initiatives, Daniel Tucker

Theses and Dissertations

The successful implementation of knowledge management (KM) initiatives requires a level of commitment and preparedness by the organization that is commensurate with the expected results. An organization must be willing to allocate the necessary resources to ensure their readiness to undertake new KM projects. The purpose of this study is to review AFWA’s organizational culture and measure its propensity for accepting KM initiatives. The study uses empirically validated constructs to evaluate and assess the organization’s people, culture, climate, processes and attitudes as they relate to KM. This research was conducted using semi-structured interviews to elicit respondents’ views about KM practices. …

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