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A Minimum Effort Control Approach To Guided Munition Path Planning, Jeffrey M. Borkowski
A Minimum Effort Control Approach To Guided Munition Path Planning, Jeffrey M. Borkowski
Theses and Dissertations
An advance in the development of smart munitions entails autonomously modifying target selection during flight to maximize the value of the target being destroyed. Target identification and classification provides a basis for target value, which is used in conjunction with multi-target tracks to determine an optimal aim point for the munition. A unique guidance law can be constructed that exploits attribute and kinematic data from an onboard video sensor. This thesis develops an innovative path planning algorithm that provides an obstacle avoidance function while navigating the munition toward the highest value target. The foundation of this path planning method is …
Using Value-Focused Thinking To Evaluate The Practicality Of Porous Pavement Parking Areas On Air Force Installations, Christopher D. Bulson
Using Value-Focused Thinking To Evaluate The Practicality Of Porous Pavement Parking Areas On Air Force Installations, Christopher D. Bulson
Theses and Dissertations
Natural runoff processes have been altered by urban development; impervious surfaces (rooftops, highways, parking areas) and their associated storm water systems channel runoff from a vast area into one concentrated outflow. This storm water runoff can cause erosion, flooding, landslides, and significant damage to aquatic ecosystems. Runoff from highways and parking areas has also been known to contain high levels of suspended solids, heavy metals and hydrocarbons. Porous pavements allow infiltration of water through typically impervious surfaces, reducing storm water volumes and acting as a pollutant filtration system. Since there is currently no methodology for Air Force decision-makers to compare …
Building A Consensus Forecast For Crude Oil Prices, Kenneth W. Burke
Building A Consensus Forecast For Crude Oil Prices, Kenneth W. Burke
Theses and Dissertations
Skyrocketing fuel prices have stressed the Department of Defense's budget in recent years. In 2001 the DoD spent $4.7 Billion on fuel with the Air Force consuming $2.7 Billion. These figures have grown over due to these increases as well as the increased flying ours to support the Global War On Terror. In fact, the Fiscal Year 2007 budget has already been increased by $1.1 billion, or 1% of the total budget, to accommodate the increased price of fuel. Current forecasts of this resource have yielded poor results, impairing the DoD's ability to budget this critical expense. Further because the …
A Study Of Near Field Data Transformed To The Far Field For A Canonical Pec Scatterer, E. Matthew Cady
A Study Of Near Field Data Transformed To The Far Field For A Canonical Pec Scatterer, E. Matthew Cady
Theses and Dissertations
The purpose of this research was to analyze the error associated with the Image Based Near Field to Far Field Transformation (IB NFFFT) for a canonical perfectly electrically conductive (PEC) scatterer. This research compares two groups of data: far field RCS predicted by the IB NFFFT and far field RCS predicted by X-Patch. The IB NFFFT requires a complete set of calibrated monostatic near field scattering data of the object. A detailed description is given of the configuration of the measurement facilities and procedures that were required to obtain the calibrated near field scattering data, as well as the process …
Bda Enhancement Methodology Using Situational Parameter Adjustments, Michael V. Carras Jr.
Bda Enhancement Methodology Using Situational Parameter Adjustments, Michael V. Carras Jr.
Theses and Dissertations
In the context of close ground combat, the perception of Battle Damage Assessment (BDA) is closely linked with a soldier’s engagement decisions and has significant effects on the battlefield. Perceived BDA is also one of the most complex and uncertain processes facing the soldier in live combat. As a result, the modeling and simulation community has yet to adequately model the perceived BDA process in combat models. This research effort examines the BDA process from a perception standpoint and proposes a methodology to collect the pertinent data and model this perception in the Army’s current force-on-force model, CASTFOREM. A subject …
Image Processing Resource Allocation Methods For Multi-Target Tracking Of Dismounted Targets In Urban Environments, Jonathan P. Champion
Image Processing Resource Allocation Methods For Multi-Target Tracking Of Dismounted Targets In Urban Environments, Jonathan P. Champion
Theses and Dissertations
Dismounted targets can be tracked in urban environments with video sensors. Real-time systems are unable to process all of the imagery, demanding some method for prioritization of the processing resources. Furthermore, various segmentation algorithms exist within image processing, each algorithm possesses unique capabilities, and each algorithm has an associated computational cost. Additional complexity arises in the prioritization problem when targets become occluded (e.g., by a building) and when the targets are intermixed with other dismounted entities. This added complexity leads to the question "which portions of the scene warrant both low cost and high cost processing?" The approach presented in …
Characterization Of Functionally Graded Materials, Benjamin D. Chapman
Characterization Of Functionally Graded Materials, Benjamin D. Chapman
Theses and Dissertations
The purpose of this study was to characterize the behavior of a functionally graded material through experimentation and analytical modeling. Functionally graded materials are a ceramic metal composite which transitions from metal on one face to ceramic on the opposite face. Creating reliable models required verifying the material properties. This was accomplished through the use of a static modulus of elasticity test as well as a dynamic ping test. The natural frequencies from the dynamic test were compared with finite element models to determine which material properties most accurately represented the functionally graded material. It was found that the material …
Computational Modeling Of The Dielectric Barrier Discharge (Dbd) Device For Aeronautical Applications, Christopher S. Charles
Computational Modeling Of The Dielectric Barrier Discharge (Dbd) Device For Aeronautical Applications, Christopher S. Charles
Theses and Dissertations
Dielectric Barrier Discharge (DBD) type devices, when used as plasma actuators, have shown significant promise for use in many aeronautical applications. Experimentally, DBD actuator devices have been shown to induce motion in initially still air, and to cause re-attachment of air flow over a wing surface at a high angle of attack. This thesis explores the numerical simulation of the DBD device in both a lD and 2D environment. Using well established fluid equation techniques, along with the appropriate approximations for the regime under which these devices will be operating, computational results for various conditions and geometries are explored. In …
Characteristics Of Two-Dimensional Triangular And Three-Dimensional Face-Centered-Cubic Photonic Crystals, Jeffery D. Clark
Characteristics Of Two-Dimensional Triangular And Three-Dimensional Face-Centered-Cubic Photonic Crystals, Jeffery D. Clark
Theses and Dissertations
The fabrication of photonic crystals (PhC) with photonic band gaps (PBG) in the visible range is a difficult task due to the small structural feature sizes of the PhC. The particular type of PhC examined is a two-dimensional (2-D) triangular structure with a PBG designed for visible wavelengths with applications in visible integrated photonic systems. This work examines the processes involved and viability of fabricating 2-D triangular PhC's by a variety of techniques: focused ion beam, electron lithography and holographic photo-polymerization/lithography. The design of the PhC was based on a program created to display gap maps for triangular structures. The …
Estimating Required Contingency Funds For Construction Projects Using Multiple Linear Regression, Jason J. Cook
Estimating Required Contingency Funds For Construction Projects Using Multiple Linear Regression, Jason J. Cook
Theses and Dissertations
Cost overruns are a critical problem for construction projects. The common practice for dealing with cost overruns is the assignment of an arbitrary flat percentage of the construction budget as a contingency fund. This research seeks to identify significant factors that may influence, or serve as indicators of, potential cost overruns. The study uses data on 243 construction projects over a full range of project types and scopes gathered from an existing United States Air Force construction database. The author uses multiple linear regression to analyze the data and compares the proposed model to the common practice of assigning contingency …
Analysis Of Bacterial Population And Distribution In The Developing Strata Of A Constructed Wetland Used For Chlorinated Ethene Bioremediation, Milton J. Clausen Jr.
Analysis Of Bacterial Population And Distribution In The Developing Strata Of A Constructed Wetland Used For Chlorinated Ethene Bioremediation, Milton J. Clausen Jr.
Theses and Dissertations
Chlorinated hydrocarbons and their degradation products are among of the most common organic groundwater contaminates in the United States. These compounds attack the central nervous system in animals and can affect the photosynthesis of plants. These compounds are also resistant to degradation in the environment and, because of this, pose a risk to any ecosystem in which they are present. This study identified the dominant microbial species in a constructed treatment wetland at Wright-Patterson AFB, Dayton, Ohio using 16S rRNA gene sequence analysis. Samples were taken from three different depths and during each of the four seasons. These samples were …
Spatially-Resolved Temperature Diagnostic For Supersonic Flow Using Cross-Beam Doppler-Limited Laser Saturation Spectroscopy, Grady T. Phillips
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 …
Characterization Of Detonation Phenomena Observed In High-Speed Visible Imagery, Trevor W. Warren
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, …
Doppler-Only Multistatic Radar, Dustin G. Mixon
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 …
Selecting Energy Efficient Building Envelope Retrofits To Existing Department Of Defense Building Using Value Focused Thinking, David M. Pratt
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 …
Factors Affecting The Transfer Of Basic Combat Skills Training In The Air Force, Rodney E. Mccraine
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 …
Formation Flight Control For Aerial Refueling, Steven M. Ross
Formation Flight Control For Aerial Refueling, Steven M. Ross
Theses and Dissertations
A controller is designed for an aircraft to autonomously fly formation during aerial refueling. Requirements for a refueling autopilot are stated. A six-degree-of-freedom model is developed for an F-16 lead aircraft and a Learjet LJ-25 wing aircraft. Bare airframe stability of both aircraft is investigated, and stability augmentation is performed. A Matlab Simulink® simulation is built to reproduce the sensor inputs that will be available to the wing aircraft in flight, including disturbances. Control frames are investigated to determine the optimum presentation of the error vector for control during the task of air refueling. Control laws are developed from the …
Multiframe Shift Estimation, Stephen A. Bruckart
Multiframe Shift Estimation, Stephen A. Bruckart
Theses and Dissertations
The purpose of this research was to develop a fundamental framework for a new approach to multiframe translational shift estimation in image processing. This thesis sought to create a new multiframe shift estimator, to theoretically prove and experimentally test key properties of it, and to quantify its performance according to several metrics. The new estimator was modeled successfully and was proven to be an unbiased estimator under certain common image noise conditions. Furthermore its performance was shown to be superior to the cross correlation shift estimator, a robust estimator widely used in similar image processing cases, according to several criteria. …
An Estimation Theory Approach To Detection And Ranging Of Obscured Targets In 3-D Ladar Data, Charles R. Burris
An Estimation Theory Approach To Detection And Ranging Of Obscured Targets In 3-D Ladar Data, Charles R. Burris
Theses and Dissertations
The purpose of this research is to develop an algorithm to detect obscured images in 3-D LADAR data. The real data used for this research was gathered using a FLASH LADAR system under development at AFRL/SNJM. The system transmits light with a wavelength of 1.55 micrometers and produces 20 128 X 128 temporally resolved images from the return pulse separated by less than 2 nanoseconds in time. New algorithms for estimating the range to a target in 3-D FLASH LADAR data were developed. Results from processing real data are presented and compared to the traditional correlation receiver for extracting ranges …
Data Analysis And Its Impact On Predicting Schedule & Cost Risk, Steven M. Cross
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 …
Quantitative Object Reconstruction Using Abel Transform Tomography And Mixed Variable Optimization, Kevin R. O'Reilly
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 …
A Risk Assessment Methodology For Divesting Military Capabilities To Allied Nations, Jason A. Gastelum
A Risk Assessment Methodology For Divesting Military Capabilities To Allied Nations, Jason A. Gastelum
Theses and Dissertations
The United States spent over $400 billion dollars on national defense in 2005. Even with support for the war on terrorism still strong, it is doubtful that the U.S. can sustain such a level of defense investment. One strategy to offset the increasing burden of defense spending is to divest the procurement and/or sustainment of individual defense capabilities to allied nations. The decision to divest any capability, however, introduces risk. This thesis presents a methodology to quantify the risk of the decision to divest a military capability to an allied nation, where risk is defined as the set of risk …
Development Of A Comprehensive Digital Avionics Curriculum For The Aeronautical Engineer, Thomas W. Hofer
Development Of A Comprehensive Digital Avionics Curriculum For The Aeronautical Engineer, Thomas W. Hofer
Theses and Dissertations
The purpose of this research was to develop a comprehensive digital avionics curriculum for aeronautical engineering students at AFIT. Due to the closing of the aeronautical engineering program at the Naval Postgraduate School, and the subsequent requirement to establish a digital avionics specialty course sequence at AFIT, a mature avionics curriculum does not yet exist that satisfies the needs of graduates who will serve as aeronautical engineers involved with the development, integration, testing, fielding, and supporting of military avionics systems as part of the overall aircraft system. Research was conducted through a comprehensive literature review and the use of a …
Detecting Potential Insider Threats Through Email Datamining, James S. Okolica
Detecting Potential Insider Threats Through Email Datamining, James S. Okolica
Theses and Dissertations
No abstract provided.
Doppler Aliasing Reduction In Wide-Angle Synthetic Aperture Radar Using Phase Modulated Random Stepped-Frequency Waveforms, Andrew W. Hyatt
Doppler Aliasing Reduction In Wide-Angle Synthetic Aperture Radar Using Phase Modulated Random Stepped-Frequency Waveforms, Andrew W. Hyatt
Theses and Dissertations
This research effort examines the theory, application and results of side-looking airborne radar operation in hot clutter. Hot clutter is an electronic counter-measure used to degrade the performance of airborne radar. Hot clutter occurs by illuminating the ground with an airborne jammer at some velocity, azimuth, elevation, and range from the airborne radar. When the received RCS scattered hot clutter waveform is perfectly coherent with the radar waveform, the radar believes the returns created by the hot clutter jammer resulted from the transmitting radar. Hot clutter degrades radar performance at locations in azimuth and Doppler. The effect of hot clutter …
Biological System Impedance Identification Using Stochastic Estimation And Control, Enrique Mendezaceves
Biological System Impedance Identification Using Stochastic Estimation And Control, Enrique Mendezaceves
Theses and Dissertations
In an effort to find a less invasive way of testing for different cell abnormalities and finding more practical tests for different cellular mutations, this project makes use of a well-known technique called cellular impedance spectroscopy coupled with stochastic estimation. Impedance spectroscopy, the measurement of the complex resistance of a biological body, is not a new technology; it has been around for many years and has been used to make electrical representations of different biological systems. The problem with this procedure is that models cannot be used for system identification. Stochastic estimation can complement a model produced by analyzing the …
Multi-Dimensional Wave Front Sensing Algorithms For Embedded Tracking And Adaptive Optics Applications, Christopher C. Wood
Multi-Dimensional Wave Front Sensing Algorithms For Embedded Tracking And Adaptive Optics Applications, Christopher C. Wood
Theses and Dissertations
Current tracking and adaptive optics techniques cannot compensate for fast-moving extended objects, which is important for ground-based telescopes providing space situational awareness. To fill this need, a vector-projection maximum-likelihood wave-front sensing algorithm development and testing follows for this application. A derivation and simplification of the Cramer-Rao Lower Bound for wavefront sensing using a laser guide star bounds the performance of these systems and guides implementation of a vastly optimized maximum-likelihood search algorithm. A complete analysis of the bias, mean square error, and variance of the algorithm demonstrates exceptional performance of the new sensor. A proof of concept implementation shows feasibility …
Simulation Of A Moving Elastic Beam Using Hamilton's Weak Principle, Elliott J. Leigh
Simulation Of A Moving Elastic Beam Using Hamilton's Weak Principle, Elliott J. Leigh
Theses and Dissertations
Hamilton's Law is derived in weak form for slender beams with closed cross sections. The result is discretized with mixed space-time finite elements to yield a system of nonlinear, algebraic equations. An algorithm is proposed for solving these equations using unconstrained optimization techniques, obtaining steady-state and time accurate solutions for problems of structural dynamics. This technique provides accurate solutions for nonlinear static and steady-state problems including the cantilevered elastica and flatwise rotation of beams. Modal analysis of beams and rods is investigated to accurately determine fundamental frequencies of vibration, and the simulation of simple maneuvers is demonstrated.
Cfd Investigation Of The Flow Dynamics Inside A Spherical Surface Indentation, Robert C. Vincent
Cfd Investigation Of The Flow Dynamics Inside A Spherical Surface Indentation, Robert C. Vincent
Theses and Dissertations
This study aims to identify the flow structure inside and around a dimple surface indentation that passively reduces flow separation, and to generate characterization parameters for the effectiveness of the aforementioned flow structure in boundary layer separation control. In this study the surface indentation is cut into a flat plate in a diverging channel that creates an adverse pressure gradient. In the baseline flat plate conditions, the shedding vortices formed by the pressure gradient create an oscillating pressure field in the dimple. This geometry has been chosen to simulate the adverse pressure gradient present in the flow regime found on …
Space-Time Adaptive Processing For Side-Looking Arrays With Platform Maneuver, John T. Buckreis
Space-Time Adaptive Processing For Side-Looking Arrays With Platform Maneuver, John T. Buckreis
Theses and Dissertations
This research effort develops a space-time adaptive processing (STAP) radar data model for the side-looking (SL) array with platform maneuver. A primary assumption of most STAP models is the absence of platform maneuver during the coherent processing interval (CPI). This research abandons the platform stationarity assumption, allowing platform pitch, roll, and yaw during the CPI. The model developed characterizes platform maneuver effects on the clutter spectrum, examines Matched Filter (MF) output Signal-to-Interference-plus-Noise-Ratio (SINR), and investigates maneuver impact on sample support homogeneity. The introduction of pitch marginally impacts MF SINR due to the lack of achieved azimuth resolution in this research, …