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Combined Stereo Vision And Inertial Navigation For Automated Aerial Refueling, Daniel T. Johnson
Combined Stereo Vision And Inertial Navigation For Automated Aerial Refueling, Daniel T. Johnson
Theses and Dissertations
This paper describes the design of an EKF to obtain the precise relative position of two aircraft in a refueling maneuver while operating in GPS denied environments. The EKF uses the INS already present in both aircraft as well as the stereo camera system organic to new tanker systems. The aircraft trajectories are generated according to authentic refueling profiles with flight dynamics software and executed in a 3D virtual environment to enable deterministic simulation of the stereo camera system and to demonstrate the effectiveness of the combined system in a refueling scenario. Results show the system can achieve sufficient accuracy …
A Framework For Understanding, Prioritizing, And Applying Systems Security Engineering Processes, Activities, And Tasks, Stephen Khou
A Framework For Understanding, Prioritizing, And Applying Systems Security Engineering Processes, Activities, And Tasks, Stephen Khou
Theses and Dissertations
Current systems security practices lack an effective approach to prioritize and tailor systems security efforts to develop and field secure systems in challenging operational environments, which results in business and mission stakeholders becoming more susceptible to an array of disruptive events. This work informs Systems Engineers on recent developments in the field of system security engineering and provides a framework for more fully understanding the application of Systems Security Engineering (SSE) processes, activities, and tasks as described in the recently released National Institute of Standards and Technology (NIST) Special Publication 800-160. This SSE framework uniquely offers a repeatable and tailorable …
Survival Analysis Of Us Air Force Officer Retention Rate, Courtney N. Franzen
Survival Analysis Of Us Air Force Officer Retention Rate, Courtney N. Franzen
Theses and Dissertations
Personnel retention is a matter of great interest in the private and public sectors. In the public sector--specifically the US Air Force--maintaining appropriate retention levels of rated officers is paramount as these officers are the backbone of the Air Force’s mission. As part of the effort to ensure proper retention rates for rated officers, retention models are created by the Air Force Personnel division that assist in predicting future retention patterns and accession needs. The techniques for creating these models, known as the "sustainment line," involve utilizing average retention percentages obtained from historical data. In this study, more statistical-based methods …
Analyzing The Critical Supply Chain For Unmanned Aircraft Systems, Megan L. Muniz
Analyzing The Critical Supply Chain For Unmanned Aircraft Systems, Megan L. Muniz
Theses and Dissertations
Unmanned aerial systems (UAS) play a vital role in present day operations due their asset capability and ability to reduce risk to pilots’ lives. A complex supply chain network capable of producing and integrating all raw materials, components, sub- systems, and systems supports the successful acquisition of a UAS. Such a complex network is supported by vital supply chain decisions. Two important decisions regarding supply chain design include supplier selection and optimal flow of material and product Whether a decision maker wishes to design or interdict a supply chain, the methodology developed in this thesis provides a suite of tailorable …
Optimal Design Of A Hexakis Icosahedron Vacuum Based Lighter Than Air Vehicle, Joseph R. Schwemmer
Optimal Design Of A Hexakis Icosahedron Vacuum Based Lighter Than Air Vehicle, Joseph R. Schwemmer
Theses and Dissertations
Due to the rising cost and scarcity of helium, new methods to ensure buoyancy for lighter-than-air vehicles (LTAVs) are being sought. One alternative under study uses an internal vacuum to reduce the weight to buoyancy ratio. It's a novel approach; however, the vacuum presents challenges for the vehicle's structure. The structure must have minimum mass while preventing buckling and excess stress throughout the frame and membrane. The structure under analysis is a hexakis icosahedron with a membrane covering. Achieving minimum mass involves optimizing the structure under the loading conditions. Finite-element analysis (FEA) and direct-search methods are employed, providing an optimal …
Application Of Enlisted Force Retention Levels And Career Field Stability, Jamie T. Zimmermann
Application Of Enlisted Force Retention Levels And Career Field Stability, Jamie T. Zimmermann
Theses and Dissertations
The Air Force’s success is influenced by the manpower it has. The end-strength is Congressionally mandated. Predicting personnel retention is critical to the operations of the military. Over 10 years ago, the Air Force produced enlisted career field sustainment lines based on manning. If a career field was over manned the authorizations were decreased, likewise if a career field was under manned the authorizations were increased. The constant fluctuation of manning caused bathtubs to be created and requirements to go unfilled. Currently, the Air Force produces enlisted career field sustainment lines based on the 5-year historical retention rates. This method …
A Cost Benefit Analysis Of Emerging Led Water Purification Systems In Expeditionary Environments, Alicia D. Binggeli
A Cost Benefit Analysis Of Emerging Led Water Purification Systems In Expeditionary Environments, Alicia D. Binggeli
Theses and Dissertations
The Air Force is a rapid mobile force responsible for national defense and reaction to calls for humanitarian aid across the globe. Rapid Global Mobility is a major tenant of the Air Force strategy. It provides the nation its global reach, underpins its role as a global power, and ensures that tomorrow, just as today, the United States can respond quickly and decisively to unexpected challenges to its interests. The ability to produce or acquire potable water is an essential piece of this tenant. Reverse Osmosis Water Purifications Units (ROWPUs), the workhorse for all military units, provide all the necessary …
Forecasting Traditional Vs Blended Retirement System For Individual Service Members, Kevin M. Dwyer
Forecasting Traditional Vs Blended Retirement System For Individual Service Members, Kevin M. Dwyer
Theses and Dissertations
Starting January 1, 2018, the Department of Defense new Blended Retirement System (BRS) will go into effect. Military members with less than twelve years of service will have the option to either remain in the current High 3 Retirement System or opt into the BRS. This decision will have a lasting impact on their lives well beyond their military careers. With this in mind, we have developed a Decision Support System that will enable service members to compare the two retirement choices in terms of annual and total lifetime expected value. There were three phases to the development of the …
The Impacts Of Climate Change And Anthropogenic Processes On Permafrost Soils And Usaf Infrastructure Within Northern Tier Bases, Alexander J. Graboski
The Impacts Of Climate Change And Anthropogenic Processes On Permafrost Soils And Usaf Infrastructure Within Northern Tier Bases, Alexander J. Graboski
Theses and Dissertations
The Department of Defense is planning over $552M in military construction on Eielson Air Force Base within the next three fiscal years. Although many studies have been conducted on permafrost and climate change, the future of our climate as well as any impacts on permafrost soils, remains unclear. This research focused on future climate predictions to determine likely scenarios for the United States Air Force’s Strategic Planners to consider. The most recent 2013 International Panel on Climate Change report predicts a 2.2ºC to 7.8ºC temperature rise in Arctic regions by the end of the 21st Century in the Representative Concentration …
Increasing Cyber Resiliency Of Industrial Control Systems, Andrew J. Chaves
Increasing Cyber Resiliency Of Industrial Control Systems, Andrew J. Chaves
Theses and Dissertations
Industrial control systems (ICS) are designed to be resilient, capable of recovering from process faults and failures with limited impact to operations. Current ICS resiliency strategies use redundant PLCs. However, these redundant PLCs, being of similar make and model, can be exploited by the same cyber attack, defeating the ICS's resiliency strategy. This research proposes a resiliency strategy for ICS that employs an active defense technique to remove the cyber common cause failure. The resiliency of the active defense strategy is compared to traditional ICS resiliency by implementing both strategies in a semi-simulated wastewater treatment plant aeration basin that experiences …
A Longitudinal Study And Color Rating System Of Acquisition Cost Growth, Cory N. D'Amico
A Longitudinal Study And Color Rating System Of Acquisition Cost Growth, Cory N. D'Amico
Theses and Dissertations
different angles have been looked at to try and discover how to better estimate cost, what causes cost growth, and how to mitigate it. This research addresses this through examining cost growth from a longitudinal perspective, evaluating cost growth factors at major program reviews, and assessing the cost growth by applying color rating metrics. The results of this analysis show that breaking cost growth into longitudinal segments of a programs lifecycle allows the true behavior of cost growth to be seen, when it can often be masked in the traditional approach of evaluating lifecycle cost growth. Additionally, when applying the …
Engineering Change Orders And Their Impact On Dod Acquisition Contracts, Ian S. Cordell
Engineering Change Orders And Their Impact On Dod Acquisition Contracts, Ian S. Cordell
Theses and Dissertations
Cost growth is a problem DoD wide. Cost Estimators attempt to remedy this problem by accounting for uncertainty in the estimates they complete. They use tools such as Engineering Change Orders (ECO’s) to account for the uncertainty, by applying a percentage to the final amount estimated. The following research gives the acquisition community a more precise tool to predict whether a DoD Acquisition Contract will have an Engineering Change Order, which can then be used also during programmatic cost estimating, and also a method for predicting the proper amount of ECO to apply when certain variables are present. The study …
Perception Vs. Reality: Improving Mission Commander Decision-Making Capabilities By Use Of Heart Rate Zone Feedback In Training Environments, Caitlin M. Oviatt
Perception Vs. Reality: Improving Mission Commander Decision-Making Capabilities By Use Of Heart Rate Zone Feedback In Training Environments, Caitlin M. Oviatt
Theses and Dissertations
In the military environment, it is common for commanders to rely exclusively on perceptional information (e.g., visual observations) to make decisions on their personnel’s physical capabilities. There is little evidence to support the idea that the information provided by physiological feedback technology, typically made available to the individual visually, could improve assessments and decision-making capabilities of outside observers (e.g., mission commander in a remote location). Through experimental examination this research shows that commanders who have Heart Rate Zone (HRZ) biofeedback information about their Airmen by use of physiological technology were able to more accurately predict the level of effort and …
Using Multiple And Logistic Regression To Estimate The Median Will-Cost And Probability Of Cost And Schedule Overrun For Program Managers, Ryan C. Trudelle
Using Multiple And Logistic Regression To Estimate The Median Will-Cost And Probability Of Cost And Schedule Overrun For Program Managers, Ryan C. Trudelle
Theses and Dissertations
The main concern of a program manager is to manage the cost, schedule, and performance triad of a program. Historically, programs tend to meet the performance aspect at the expense of cost or schedule, or both. This research gives the acquisition community a set of tools that enables them to impartially analyze the cost and schedule of their programs, helping to mitigate these issues. Five regression models encompass this toolset; one to estimate the median program cost and four to identify the probability of realizing a given overrun. The cost model explains 81% of the variation in program acquisition using …
The Air Force Fitness Test: Creating New Fitness Assessment Charts Using Waist To Height Ratios, John R. Griffith
The Air Force Fitness Test: Creating New Fitness Assessment Charts Using Waist To Height Ratios, John R. Griffith
Theses and Dissertations
The Air Force currently uses AFI 36-2905 for fitness standards and evaluation, but no study to our knowledge has evaluated these standards using large databases. Using a 5.38 million record database from the Air Force Fitness Management System, we evaluated how the abdominal circumference, body mass index (BMI), waist to height ratio (WtHR), and height to weight ratio correlated to fitness as assessed by the 1.5 mile aerobic run in the Air Force Fitness Test. Whether individually or adjusting for age group and gender, WtHR performed better that the rest with an average rank score of 1.1 with a relative …
Total Electron Count Variability And Stratospheric Ozone Effects On Solar Backscatter And Lwir Emissions, John S. Ross
Total Electron Count Variability And Stratospheric Ozone Effects On Solar Backscatter And Lwir Emissions, John S. Ross
Theses and Dissertations
The development of an accurate ionospheric Total Electron Content (TEC) model is of critical importance to High Frequency (HF) radio wave propagation. However, the TEC is highly variable and is continuously influenced by geomagnetic storms, extreme Ultraviolet (UV) radiation, diurnal variation, and planetary waves. The ability to capture this variability is essential to improve current TEC models. Analysis of the growing body of data involving ionospheric fluctuations and thermal tides has revealed persistent correlation between increases in stratospheric ozone and variability of the TEC. The spectral properties of ozone show that it is a greenhouse gas that alters longwave emissions …
On Proportionate And Truthful International Alliance Contributions: An Analysis Of Incentive Compatible Cost Sharing Mechanisms To Burden Sharing, William N. Caballero
On Proportionate And Truthful International Alliance Contributions: An Analysis Of Incentive Compatible Cost Sharing Mechanisms To Burden Sharing, William N. Caballero
Theses and Dissertations
Burden sharing within an international alliance is a contentious topic, especially in the current geopolitical environment, that in practice is generally imposed by a central authority's perception of its members' abilities to contribute. Instead, we propose a cost sharing mechanism such that burden shares are allocated to nations based on their honest declarations of the alliance's worth. Specifically, we develop a set of multiobjective nonlinear optimization problem formulations that respectively impose Bayesian Incentive Compatible (BIC), Strategyproof (SP), and Group Strategyproof (GSP) mechanisms based on probabilistic inspection efforts and deception penalties that are budget balanced and in the core. Any feasible …
A Scenario-Based Parametric Analysis Of Stable Marriage Approaches To The Army Officer Assignment Problem, Matthew D. Ferguson
A Scenario-Based Parametric Analysis Of Stable Marriage Approaches To The Army Officer Assignment Problem, Matthew D. Ferguson
Theses and Dissertations
This paper compares linear programming and stable marriage approaches to the assignment problem under conditions of uncertainty. Robust solutions should exhibit reduced variability in the presence of one or more additional constraints. Several variations of each approach are compared with respect to solution quality, as measured by the overall social welfare among Officers and Assignments, and robustness as measured by the number of changes after a number of randomized perturbations. We examine the contrasts between these methods in the context of assigning Army Officers among a set of identified assignments. Additional constraints are modeled after realistic scenarios faced by Army …
Time-Dependent Validation Of Finite Element Strain Distribution Of A Plastically-Deformed Plate Via Digital Image Correlation, Kevin R. Knapp
Time-Dependent Validation Of Finite Element Strain Distribution Of A Plastically-Deformed Plate Via Digital Image Correlation, Kevin R. Knapp
Theses and Dissertations
Generation of residual stress is an essential step in the generation of Goodman data via Air Force Research Laboratory's vibration-based fatigue test. Conventional Goodman data is constructed through uniaxial fatigue testing at a rate of 40 Hz, while the vibration-based testing excites stresses at 1,600 Hz in a stress state that is similar to those seen in gas turbine engine airfoils. A pre-strain procedure is conducted to form residual tensile stress, which serves as a steady stress when the specimen is subjected to fully-reversed vibration-based fatigue loads. This steady tensile stress is desired at the fatigue zone of the test …
Resource Evaluation Of Quantum Linear Systems Algorithm For Application To Electromagnetic Scattering Problems, Casey J.R. Riggs
Resource Evaluation Of Quantum Linear Systems Algorithm For Application To Electromagnetic Scattering Problems, Casey J.R. Riggs
Theses and Dissertations
Current limitations in quantum computing technology does not allow for very large applications of quantum algorithms, and it is the nature of quantum algorithms not only to be able to solve problems of interest much more quickly than classical means but also to do so with less resources which makes them so promising! One such problem of interest is the application of the Quantum Linear Systems Algorithm, along with a few other subroutines, to the calculation of an electromagnetic scattering cross-section via finite element methods. This work composes a resource analysis of the algorithm as well as required subroutines and …
Predicting Solar Performance In A Contingency Environment To Meet Net-Zero Facility Power, Anthony D. Williams
Predicting Solar Performance In A Contingency Environment To Meet Net-Zero Facility Power, Anthony D. Williams
Theses and Dissertations
The U.S. government is involved in contingency operations all over the world and these operations require operational support and sustainment in these locations; this includes the reliable delivery of power to base infrastructure. The traditional means of delivering this support requirement in austere environments has been the use of diesel-power generation that has an extensive logistical and economic tail. The research sought out contingency solar applications that may be implemented and operated to offset the facility demand loads in the location to achieve net-zero power. This research explores the technical feasibility of a deployable photovoltaic microgrid to deliver power to …
Implication Of Additive Manufacturing On United States Air Force Expeditionary Civil Engineer Squadron Supply Chain, Shane R. Veitenheimer
Implication Of Additive Manufacturing On United States Air Force Expeditionary Civil Engineer Squadron Supply Chain, Shane R. Veitenheimer
Theses and Dissertations
Additive manufacturing is mandated as a technology for the Department of Defense to consider to implement. Previous efforts have shown positive potential for additive manufacturing (AM) for United States Air Force Civil Engineering but do not explore the economic impact. This research examines implementation by investigating a specific Explosive Ordnance Disposal repair part supply chain in the current combat theater of operations. A framework to capture the basic financial savings AM could realize was developed to aid AM decision making. This research established a Scenario Planning and Monte Carlo simulation based framework to produce an estimated annual cost for a …
The Impact Of Atmospheric Fluctuations On Optimal Boost Glide Hypersonic Vehicle Dynamics, Melissa A. Dunkel
The Impact Of Atmospheric Fluctuations On Optimal Boost Glide Hypersonic Vehicle Dynamics, Melissa A. Dunkel
Theses and Dissertations
A project under the management of Air Force Research Laboratory has begun development of a six degree of freedom model for use in hypersonic vehicle development and application. One area of interest is the perturbation of vehicle behavior based on atmospheric fluctuations – how the performance of the vehicle changes with respect to “hot”, “cold” and standard day conditions. The method developed to fill this need uses real-world data from the Global Forecast System to create a “hot” and “cold” day dataset to compare with the standard day model. The key parameter is atmospheric density, a value calculated over a …
Experimental Validation Of A Heterogeneous Radar Clutter Statistical Estimation Method, Elliot R. Erstein
Experimental Validation Of A Heterogeneous Radar Clutter Statistical Estimation Method, Elliot R. Erstein
Theses and Dissertations
Radar clutter models are important for radar target detection when clutter is present. A new method for estimating single clutter type, homogeneous, radar clutter statistics through measurement of a multiple type, heterogeneous clutter was developed in 2015 by researchers at the Air Force Institute of Technology. The estimation method is greatly valued in the clutter research and modeling world for reducing clutter campaign measurement time and cost. This thesis looks at validation steps for the estimation method through the use of simulations and experimental radar clutter measurements.
Applying Cyber Threat Intelligence To Industrial Control Systems, Matthew P. Sibiga
Applying Cyber Threat Intelligence To Industrial Control Systems, Matthew P. Sibiga
Theses and Dissertations
A cybersecurity initiative known as cyber threat intelligence (CTI) has recently been developed and deployed. The overall goal of this new technology is to help protect network infrastructures. Threat intelligence platforms (TIPs) have also been created to help facilitate CTI effectiveness within organizations. There are many benefits that both can achieve within the information technology (IT) sector. The industrial control system (ICS) sector can also benefit from these technologies as most ICS networks are connected to IT networks. CTI and TIPs become resourceful when using indicators of compromise (IOCs) from known ICS malware attacks and an open source intrusion detection …
A Sandbox In Which To Learn And Develop Soar Agents, Daniel Lugo
A Sandbox In Which To Learn And Develop Soar Agents, Daniel Lugo
Theses and Dissertations
It is common for military personnel to leverage simulations (and simulators) as cost-effective tools to train and become proficient at various tasks (e.g., flying an aircraft and/or performing a mission, among others). These training simulations often need to represent humans within the simulated world in a realistic manner. Realistic implies creating simulated humans that exhibit behaviors that mimic real-world decision making and actions. Typically, to create the decision-making logic, techniques developed from the domain of artificial intelligence are used. Although there are several approaches to developing intelligent agents; we focus on leveraging and open source project called Soar, to define …
Formation Flight Of Earth Satellites On Kam Torus Using Classical Orbital Elements, Marissa C. Reabe
Formation Flight Of Earth Satellites On Kam Torus Using Classical Orbital Elements, Marissa C. Reabe
Theses and Dissertations
This research uses the KAM theory that has been refined by Wiesel to show that Earth-satellites dynamics can be represented by an integrable Hamiltonian system with a small perturbation, like Earths geopotential. The satellite will follow a torus in phase space and remain on that KAM torus for all time unless acted on by a non-conservative force. A torus frequency was calculated, in this research, using a truth model in System Tool Kit (STK) and the High Precision Orbit Propagator (HPOP) to develop an accurate ephemeris file listing the Classical Orbital Elements (COEs). The frequencies found from the truth model …
Evaluating The Autonomous Flying Qualities Of A Simulated Variable Stability Aircraft, Ali M. Hamidani
Evaluating The Autonomous Flying Qualities Of A Simulated Variable Stability Aircraft, Ali M. Hamidani
Theses and Dissertations
Delivering communications from high altitudes, at airspeeds of just 30 knots, gathering data from active volcanoes and forming hurricanes, and collecting ISR over hostile territories, UAVs are at the ready to perform those missions that are too dull, dirty, or dangerous for manned aircraft. However, the proliferation of this new technology has its fair share of challenges. Over 460 DoD UAV mishaps have occurred since 2001, with almost half resulting in damages of $2M or more. One incident almost ended in fatalities, when a UAV, suffering from loss of control, collided with a C-130. That loss of control is what …
Relating Film Cooling Performance Between Ambient And Near Engine Temperatures, Christopher J. Vorgert
Relating Film Cooling Performance Between Ambient And Near Engine Temperatures, Christopher J. Vorgert
Theses and Dissertations
This thesis explores multiple topics, including the relative importance of nondimensional parameters that relate film cooling performance within different temperature regimes and the effects of internal coolant flow and coolant temperature on overall film cooling effectiveness. A Hastelloy model representative of a turbine blade was utilized for IR tests. Near engine temperatures were produced via premixed propane and air combustion in a Well-Stirred Reactor (WSR) with air supplied as the film coolant gas. Near ambient conditions used heated air for freestream flow and carbon dioxide, argon, or air as film coolant gases. It was found that even with multiple matched …
Cavity Perturbation Technique Of 10 Ghz Cylindrical Resonator For Modeling Rf/Ir Sensor Radomes/Windows, Marvin-Ray Arida
Cavity Perturbation Technique Of 10 Ghz Cylindrical Resonator For Modeling Rf/Ir Sensor Radomes/Windows, Marvin-Ray Arida
Theses and Dissertations
The dielectric properties of candidate materials for radomes or sensor windows on hypersonic vehicles, which can reach temperatures above 1,500° Celsius when traveling greater than Mach 5, are required. Although there has been recent scientific interest in the temperature dependence of the dielectric constant, little is known for temperatures near 1,500° Celsius and above. Current research utilizes large laboratory-sized furnaces to achieve these temperatures. This also requires large sample sizes, which are expensive; such expense is greatly multiplied when sweeping through hundreds of materials for research and development. In an effort to reduce these costs, this thesis modeled a 7.0 …