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A Discrete X-Ray Transform For Chromotomographic Hyperspectral Imaging, David J. Cooke
A Discrete X-Ray Transform For Chromotomographic Hyperspectral Imaging, David J. Cooke
Theses and Dissertations
The United States Air Force has a pressing need for new methods of hyperspectral imaging. All current hyperspectral imaging technologies require long exposure times, since each involves filtering the available light, either spatially or according to color. We consider a recently proposed method for hypserspectral imaging that promises shorter exposure times. This new method applies the mathematical principles of tomography to the hyperspectral data cube. Known as chromotomography, this method uses a spinning prism to essentially capture the integrals of this cube over many rotations of a single line. This thesis addresses some of the mathematical issues that arise when …
Cost Growth Above Inflation (Cgai) In Operating And Support (O&S) Costs In Raw Materials For Air Force Aircraft, Gregory J. Ferry
Cost Growth Above Inflation (Cgai) In Operating And Support (O&S) Costs In Raw Materials For Air Force Aircraft, Gregory J. Ferry
Theses and Dissertations
Cost growth above inflation (CGAI) is the cost growth that exists after adjusting for the effects of currency inflation over time. The time value of money would suggest the increase in Operating and Support (O&S) costs over time would only be affected by inflation. In essence, every year aircraft need to be maintained at the same level and O&S costs should not change, assuming the same level of requirements. If CGAI exists in O&S there will be a large inaccuracy in the total life cycle cost (LCC) of weapon systems and an inaccurate budget put in place. An inaccurate estimate …
Distributional Monte Carlo Methods For The Boltzmann Equation, Christopher R. Schrock
Distributional Monte Carlo Methods For The Boltzmann Equation, Christopher R. Schrock
Theses and Dissertations
Stochastic particle methods (SPMs) for the Boltzmann equation, such as the Direct Simulation Monte Carlo (DSMC) technique, have gained popularity for the prediction of flows in which the assumptions behind the continuum equations of fluid mechanics break down; however, there are still a number of issues that make SPMs computationally challenging for practical use. In traditional SPMs, simulated particles may possess only a single velocity vector, even though they may represent an extremely large collection of actual particles. This limits the method to converge only in law to the Boltzmann solution. This document details the development of new SPMs that …
Multivariate And Naïve Bayes Text Classification Approach To Cost Growth Risk In Department Of Defense Acquisition Programs, Charlton E. Freeman
Multivariate And Naïve Bayes Text Classification Approach To Cost Growth Risk In Department Of Defense Acquisition Programs, Charlton E. Freeman
Theses and Dissertations
In these fiscally austere times, researchers have diligently sought methods to detect cost risk in the DOD acquisition programs. Our research effort reflects a culmination of three years of research seeking solutions to the problem of identifying programs with elevated levels of cost risk. Specifically, we applied multivariate classification and multinomial Naive Bayes text classification techniques to develop three cost risk identification models. We find our model considering a 6-month change in the estimate at complete (EAC) of greater than 5% in magnitude, identified 69.5% of the high-risk programs in our dataset with 76.21% accuracy. Next, our model considering a …
Collisional Broadening And Shift Of D1 And D2 Spectral Lines In Atomic Alkali Vapor - Noble Gas Systems, Robert D. Loper
Collisional Broadening And Shift Of D1 And D2 Spectral Lines In Atomic Alkali Vapor - Noble Gas Systems, Robert D. Loper
Theses and Dissertations
The Baranger model is used to compute collisional broadening and shift of the D1 and D2 spectral lines of M + Ng, where M = K, Rb, Cs and Ng = He, Ne, Ar, using scattering phase shift differences which are calculated from scattering matrix elements. Scattering matrix elements are calculated using the Channel Packet Method where the collisions are treated non-adiabatically and include spin-orbit and Coriolis couplings. Non-adiabatic wavepacket dynamics are determined using the split-operator method together with a unitary transformation between adiabatic and diabatic representations. Scattering phase shift differences are thermally weighted and integrated over energies ranging from …
Horn's Curve Estimation Through Multi-Dimensional Interpolation, Andrew L. Bigley
Horn's Curve Estimation Through Multi-Dimensional Interpolation, Andrew L. Bigley
Theses and Dissertations
A well-known multivariate data reduction method is principal components analysis (PCA). PCA transforms the variables under study into a set of components that are used to summarize the variation among the variables. The benefit is the dimension of the data may be reduced by the descriptive power of the components, permitting tractable analysis on large and messy datasets. Integral to successful PCA is determining when to stop extracting components - the matter is not a trivial one. A component extraction stopping rule that consistently produces reliable estimates of principal components is Horn's test. The drawback of the test is it …
A Mixed Integer Programming Model For Improving Theater Distribution Force Flow Analysis, Micah J. Hafich
A Mixed Integer Programming Model For Improving Theater Distribution Force Flow Analysis, Micah J. Hafich
Theses and Dissertations
Obtaining insight into potential vehicle mixtures that will support theater distribution, the final leg of military distribution, can be a challenging and time consuming process for United States Transportation Command (USTRANSCOM) force flow analysts. The current process of testing numerous different vehicle mixtures until separate simulation tools demonstrate feasibility is iterative and overly burdensome. Improving on existing research, a mixed integer programming model was developed to allocate specific vehicle types to delivery items, or requirements, in a manner that would minimize both operational costs and late deliveries. This gives insight into the types and amounts of vehicles necessary for feasible …
Aerial Refueling Simulator Validation Using Operational Experimentation And Response Surface Methods With Time Series Responses, Alexander P. Hillman
Aerial Refueling Simulator Validation Using Operational Experimentation And Response Surface Methods With Time Series Responses, Alexander P. Hillman
Theses and Dissertations
An important program in the Department of Defense is the KC-46 Supertanker. Dubbed the future of the Air Force's aerial refueling inventory, the KC-46 will replace dozens of ailing previous generation tanker aircraft. The Aerial Refueling Airplane Simulator Qualification document governs the methods by which Air Mobility Command validates its simulators, some of which will be KC-46 simulators in the near future. The methodology set forward in this thesis utilizes historical data of aircraft performance from similar air frames to gain statistical insight into the performance design space of the KC-46. Leveraging this insight, the methodology provides through a framework …
Traumatic Brain Injury Recovery Care: Demand Forecasting, Staffing, And Treatment Planning, Mitchell R. Kieffer
Traumatic Brain Injury Recovery Care: Demand Forecasting, Staffing, And Treatment Planning, Mitchell R. Kieffer
Theses and Dissertations
Improvised Explosive Device attacks have skyrocketed since the start of the War on Terror. Many troops wounded by these tactics receive long-lasting unseen wounds including Traumatic Brain Injury (TBI). TBI sufferers are treated along with other casualties. This has created an increasing, and varying, demand for ongoing post operative recovery care for troops returning from deployments. Diagnosis and treatment for TBI wounded troops is costly. This thesis is motivated by the recognition that budgets are constrained yet quality of care should not be compromised. Additive Holtz-Winters smoothing is used to forecast overall patient care demand, a regression based on queueing …
Estimating The Probability Of Being The Best System: A Generalized Method And Nonparametric Hypothesis Test, Aaron M. Lessin
Estimating The Probability Of Being The Best System: A Generalized Method And Nonparametric Hypothesis Test, Aaron M. Lessin
Theses and Dissertations
This thesis provides two new approaches for comparing competing systems. Instead of making comparisons based on long run averages or mean performance, the first paper presents a generalized method for calculating the probability that a single system is the best among all systems in a single trial. Unlike current empirical methods, the generalized method calculates the exact multinomial probability that a single system is best among competing systems. The ability to avoid time consuming empirical estimate techniques could potentially result in significant savings in both time and money when comparing alternate systems. A Monte Carlo simulation is conducted comparing the …
Operational Planning Of Channel Airlift Missions Using Forecasted Demand, Taylor J. Leonard
Operational Planning Of Channel Airlift Missions Using Forecasted Demand, Taylor J. Leonard
Theses and Dissertations
Past research proposed that it is possible to forecast cargo demand using time series models and that there exists potential cost savings in the way that Civilian Reserve Air Fleet (CRAF) is used for cargo airlift. United States Transportation Command (USTRANSCOM) performs annual fixed-buys of CRAF to support airlift needs. Forecasted cargo demand would allow for reasonably accurate cargo projections vs. the current expected value estimation. Accurate forecasting allows for greater fixed-buys, further incentivizing CRAF airlines as well as reducing the number of additional aircraft purchases during the quarterly and monthly buys. Multiple forecasting models are constructed and the results …
Analysis Of Effects Of Organizational Behavior On Evolving System Of Systems Acquisition Programs Through Agent Based Modeling, Klayton S. Bobsein
Analysis Of Effects Of Organizational Behavior On Evolving System Of Systems Acquisition Programs Through Agent Based Modeling, Klayton S. Bobsein
Theses and Dissertations
Every weapon system operates in context with one or more system of systems (SoS). It is the SoS that provides warfighting capability. Each system is managed independently by a program office with program-centric priorities. These systems must be interconnected and interoperable, so the program office must collaborate across the SoS. The SoS are always changing and evolving, triggered by variety of stimuli. Acquisition program offices can be characterized with a set of organizational behaviors that respond to the environment, are influenced by SoS architecture, and can be described by their fitness and contribution to SoS. Using Geert Hofstede's cultural dimensions, …
Modeling The Impact Of The Payload Alert Communications System (Pacs) On The Accuracy Of Conjunction Analysis, Landon B. Bastow
Modeling The Impact Of The Payload Alert Communications System (Pacs) On The Accuracy Of Conjunction Analysis, Landon B. Bastow
Theses and Dissertations
The Air Force Institute of Technology (AFIT) and the Air Force Research Laboratory (AFRL) are jointly developing a system known as the Payload Alert Communications System (PACS) whose purpose is to decrease the statistical uncertainty in the location of resident space objects (RSOs). PACS is designed to augment the Joint Space Operations Center's (JSpOC) existing space object tracking capabilities which is expected to increase the accuracy of conjunction estimation. In the current PACS design, a small payload would be attached to certain RSOs prior their launch. It is envisioned that this payload would basically consist of a microcontroller, a Global …
Cognitive Mentorship: Mediating Protégé Performance, Brian R. Mauntel
Cognitive Mentorship: Mediating Protégé Performance, Brian R. Mauntel
Theses and Dissertations
The role of cognitive apprenticeship has been emphasized in facilitating individual performance in the classroom, but there is limited quantitative research directly linking cognitive behaviors to mentoring relationships and workplace performance. This study investigates the characteristics of mentoring behavior that influence group performance using archival data from 52 different organizations. A mediation model is developed and the results indicate that the group-level of mentors' cognitive behavior plays a central role in the mentor-protege relationship. The findings suggest that the mentors' collective articulation of problem solving processes fully mediate the unit's performance, while reflection and exploration partially mediate the relationship. The …
An Analysis Of Cost Premiums And Losses Associated With Usaf Military Construction (Milcon), Daniel L. Blomberg
An Analysis Of Cost Premiums And Losses Associated With Usaf Military Construction (Milcon), Daniel L. Blomberg
Theses and Dissertations
Military construction (MILCON) represents 40% of the federal government's $30 billion construction budget. The federal budget is fixed; therefore, any cost overages likely affect project scope or requirements. This study investigated if MILCON procurement costs more than private industry construction and if so, what causes the cost premiums. A combination of in-depth literature review, expert interviews, a unique case study, expert surveys, and geospatial statistical analysis answered the research question. The case study evaluated two nearly identical projects to determine how internal factors affect MILCON cost premiums. This study confirmed the existence of MILCON cost premiums. Additionally, 11 major cost …
Successfully Implementing Net-Zero Engergy Policy Through The Air Force Military Construction Program, D. Gavin Brost
Successfully Implementing Net-Zero Engergy Policy Through The Air Force Military Construction Program, D. Gavin Brost
Theses and Dissertations
The U.S. Government has issued numerous policies aimed at reducing federal facility energy consumption; the most recent, Executive Order 13514, requires that new construction designed after 2020 can achieve net-zero energy by 2030. The policy defines a Zero-Energy Building as one that is designed, constructed, and operated to reduce energy demand to a level which can be offset from sources of renewable energy. This research develops and evaluates a feasibility assessment model based on life-cycle cost. It incorporates geospatial analysis to calculate and summarize input values for all Air Force installations in the Contiguous U.S. A comparative analysis is then …
Fist And The Analytical Hierarchy Process: Comparative Modeling, Trevor A . Gustafson
Fist And The Analytical Hierarchy Process: Comparative Modeling, Trevor A . Gustafson
Theses and Dissertations
FIST is an emerging and unproven rapid acquisition model that stands for Fast, Inexpensive, Simple, and Tiny. The purpose of this research is to develop an Analytical Hierarchy Process (AHP) model based on the FIST concepts, to be applied as a comparative tool against the FIST model. The results indicate that the FIST model is reproducible with the AHP theory and that there are certain program characteristics that denote if a program would benefit from being developed by FIST. However, there are distinct weaknesses to the model that signify not all programs would succeed if FIST was employed during development. …
Using Value-Focused Thinking As An Alternative Means Of Opportunity Assessment For Strategic Sourcing Applications, Andrew R. Myers
Using Value-Focused Thinking As An Alternative Means Of Opportunity Assessment For Strategic Sourcing Applications, Andrew R. Myers
Theses and Dissertations
In recent years, the Federal Government has attempted to utilize strategic sourcing to reduce acquisitions expenses. Currently accepted best practices for strategic sourcing developed in the private sector fail to account for the diverse and unique set of objectives present in public sector acquisitions. Value Focused Thinking was used to develop a hierarchy of values and objectives for the Air Force Civil Engineer Commodity Council (CECC) strategic sourcing program. This hierarchy represents the full range of program objectives, and was used to develop a value function useful for systematically evaluating service and commodity contract areas for strategic sourcing potential.
The Use Of Multi-Criteria Evaluation And Network Analysis In The Area Development Planning Process, Peeter E. Pleake-Tamm
The Use Of Multi-Criteria Evaluation And Network Analysis In The Area Development Planning Process, Peeter E. Pleake-Tamm
Theses and Dissertations
The purpose of this research was to develop improvements to the area development planning process. These plans are used to improve operations within an installation sub-section by altering the physical layout of facilities. One methodology was developed based on apply network analysis concepts to the generation of alternative facility layouts. A second methodology was developed using multi-criteria evaluation to the selection of evaluated alternative facility layouts. The results of this study are two methodological processes that can be executed at base level requiring minimal additional information. The functional network map, based in network analysis, increases the use of socio-economic data …
Development Of Autonomous Optimal Cooperative Control In Relay Rover Configured Small Unmanned Aerial Systems, Timothy J. Shuck
Development Of Autonomous Optimal Cooperative Control In Relay Rover Configured Small Unmanned Aerial Systems, Timothy J. Shuck
Theses and Dissertations
This thesis documents the research effort to develop, integrate and implement the system hardware and the software necessary to validate the Air Force Institute of Technology's theoretical advances in small unmanned aerial systems (SUAS) cooperative control. The end state objective of the research effort was to flight test an autonomous control algorithm on a communication relay unmanned aerial vehicle (UAV) that was actively relaying data to and from a rover UAV. The relay UAV is one part of a SUAS designed to utilize cooperative control to extend the effective line-of-sight operating range for a rover UAV. An algorithm is integrated …
Evaluating The Effect Of Integrated System Health Management On Mission Effectiveness, Sarah E. Storm
Evaluating The Effect Of Integrated System Health Management On Mission Effectiveness, Sarah E. Storm
Theses and Dissertations
This research used systems architecture to develop a model that determined the effect of Integrated System Health Management (ISHM) on mission success rates for unmanned aerial systems (UAS). To evaluate this effect, a simulation model was developed and used to analyze the difference between mission success rates for a theoretical UAS with and without ISHM. Design of Experiments analysis techniques were used to map a response surface that modeled the difference between mission success rates calculated for current health management technology and ISHM. Using representative data for a UAS, the analysis determined that the failure distribution parameters, sensor quality (which …
High Frequency Magnetic Field Direction Finding Using Mgl-S8a B-Dot Sensors, Michael D. Archer
High Frequency Magnetic Field Direction Finding Using Mgl-S8a B-Dot Sensors, Michael D. Archer
Theses and Dissertations
Aircraft based direction finding (DF) in the high frequency (HF) band is difficult due to the aircraft's size with respect to wavelength and limited azimuthal resolution. A B-dot sensor is useful for detection of the time varying magnetic field and offers improved integration into an aircraft. What the B-dot sensor gains in integration it gives up in sensitivity because it is designed for frequencies above 5 GHz. Design of an airborne HFDF array using Bdot sensors is based in maximizing the physical extent of the array and eliminating multiple main beams. The goals of this research are to complete a …
A Comparison Of Ionospheric Model Performance For International Space Station Orbits, David J. Broadwater
A Comparison Of Ionospheric Model Performance For International Space Station Orbits, David J. Broadwater
Theses and Dissertations
The Floating Potential Measurement Unit (FPMU) aboard the International Space Station (ISS) monitors the ISS charging environment and provides a unique electron density and electron temperature in-situ data source for the purpose of ionospheric model validation. An ionospheric model that accurately predicts the ISS plasma environment is desirable for ISS mission planning and situational awareness when FPMU data is unavailable. Electron densities and temperatures from four ionospheric models (International Reference Ionosphere [IRI], Coupled Thermosphere Ionosphere Plasmasphere Electrodynamics model [CTIPe], Ionospheric Forecast Model [IFM], and Global Assimilation of Ionospheric Measurements model [GAIM]) were compared to in-situ FPMU values across a range …
A Comparison Of Earned Value Management And Earned Schedule As Schedule Predictors On Dod Acat I Programs, Kevin T. Crumrine
A Comparison Of Earned Value Management And Earned Schedule As Schedule Predictors On Dod Acat I Programs, Kevin T. Crumrine
Theses and Dissertations
Earned Schedule, since it was introduced by Walt Lipke in 2003, has been studied extensively in a variety of different fields and on programs of all sizes. However, Earned Schedule's viability as an extension of Earned Value Management (EVM) in Major Defense Acquisition Programs (MDAP) has yet to be effectively answered. The first aspect of this research explores the breadth of Earned Schedule's adoption by the System Program Offices (SPO) of the United States Air Force. The second phase of this research explores whether Earned Schedule is a more accurate and timely schedule predictor than the EVM technique currently employed …
Opto-Mechanical Design Of A Chromotomographic Imager Direct-Vision Prism Element, Timothy E. Coon
Opto-Mechanical Design Of A Chromotomographic Imager Direct-Vision Prism Element, Timothy E. Coon
Theses and Dissertations
Chromotomographic Imaging (CTI) offers advantages in remote sensing by resolving intensity distribution spatially, spectrally, and temporally. The Chromotomography Experiment (CTEx) at the Air Force Institute of Technology (AFIT) explores the application of CTI as a space-based observer. Previous work in instrument development has revealed many of the intricacies of component fabrication and how they impact the resolving of image data. The proposed CTEx instrument has as its chromatic dispersion element a direct-vision prism (DVP) that is made to rotate in order to achieve multiple projection angles. Analysis of previous research established the need for a more accurate characterization of the …
Constitutive Parameter Measurement Using Double Ridge Waveguide, Nathan J. Lehman
Constitutive Parameter Measurement Using Double Ridge Waveguide, Nathan J. Lehman
Theses and Dissertations
Electromagnetic materials characterization is important in the design of systems that interact with electromagnetic waves. Determining the constitutive parameters of a material is a vast area of research and practice. For this paper, discussion will focus on a destructive method using waveguides in the frequency range of 6-18 GHz. Traditional methods to perform similar measurements include using coaxial cable, stripline, focus beam and rectangular waveguides. This work will use Double Ridged Waveguide (DRWG) to compare to these other methods and will discuss the attributes and drawbacks of this new approach. The most similar method utilizes rectangular waveguide, so the primary …
Rf Emitter Tracking And Intent Assessment, Benjamin J. Kuhar
Rf Emitter Tracking And Intent Assessment, Benjamin J. Kuhar
Theses and Dissertations
Current research in employing pattern recognition techniques in a wireless sensor network (WSN) to detect anomalous or suspicious behavior is limited. The purpose of this research was to determine the feasibility of an accurate tracking and intent assessment system of unknown or foreign radio frequency (RF) emitters in close proximity to and within military installations as a method for physical security. 22 position tracks were collected using a hand-held Global Positioning System (GPS) unit and a training data set from five different features was generated for each position track. Each collected position track was individually classified as suspicious or non-suspicious …
Sensitivity Analysis Of An Automated Calibration Routine For Airborne Cameras, Philip E. Lorenzini
Sensitivity Analysis Of An Automated Calibration Routine For Airborne Cameras, Philip E. Lorenzini
Theses and Dissertations
Given a known aircraft location, a set of camera calibration parameters can be used to correlate features in an image with ground locations. Previously, these calibration parameters were obtained during preflight with a lengthy calibration process. A method to automate this calibration using images taken with an aircraft mounted camera and position and attitude data is developed. This thesis seeks to determine a partial set of circumstances that affect the accuracy of the calibration results through simulation and experimental flight test. A software simulator is developed in which to test an array of aircraft maneuvers, camera orientations, and noise injection. …
Error Characterization Of Vision-Aided Navigation Systems, Daniel A . Marietta
Error Characterization Of Vision-Aided Navigation Systems, Daniel A . Marietta
Theses and Dissertations
The goal of this work is to characterize the errors committed by an Image Aided Navigation (IAN) algorithm that has been developed for use as a navigation tool in GPS denied areas. The filter under study was developed by the Air Force Institute of Technology's Advanced Navigation Technology center, and has been the focus of numerous research efforts. Unfortunately, these studies have all been based on single runs or simulations, and such results may not be indicative of the true filter performance. This problem extends to IAN publications in general; no analysis of IAN based upon a sizable real world …
The Miniaturization Of The Afit Random Noise Radar, Aaron T. Myers
The Miniaturization Of The Afit Random Noise Radar, Aaron T. Myers
Theses and Dissertations
Advances in technology and signal processing techniques have opened the door to using an UWB random noise waveform for radar imaging. This unique, low probability of intercept waveform has piqued the interest of the U.S. DoD as well as law enforcement and intelligence agencies alike. While AFIT's noise radar has made significant progress, the current architecture needs to be redesigned to meet the space constraints and power limitations of an aerial platform. This research effort is AFIT's first attempt at RNR miniaturization and centers on two primary objectives: 1) identifying a signal processor that is compact, energy efficient, and capable …