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Utilizing Software Defined Radios For Increased Bandwidth In Satellite Communications, Brian M. Wright
Utilizing Software Defined Radios For Increased Bandwidth In Satellite Communications, Brian M. Wright
Theses and Dissertations
This research explores the background and future possibilities of using cooperative satellites equipped with Software Defined Radios (SDRs) to combine their bandwidth and increase their signal reliability. Software Defined Radios are a potential solution to realize various software applications that support a reconfigurable and adaptive communication system without altering any hardware devices or features. This benefit, along with others that are offered by SDRs and the ongoing improvements in commercial digital electronics have sparked an interest in developing small satellites for advanced communications. This research effort sets out to prove if a high bandwidth signal can be generated by using …
Accurate Covariance Estimation For Pose Data From Iterative Closest Point Algorithm, Rick H. Yuan
Accurate Covariance Estimation For Pose Data From Iterative Closest Point Algorithm, Rick H. Yuan
Theses and Dissertations
One of the fundamental problems of robotics and navigation is the estimation of relative pose of an external object with respect to the observer. A common method for computing the relative pose is the Iterative Closest Point (ICP) algorithm, where a reference point cloud of a known object is registered against a sensed point cloud to determine relative pose. To use this computed pose information in down-stream processing algorithms, it is necessary to estimate the uncertainty of the ICP output, typically represented as a covariance matrix. In this thesis a novel method for estimating uncertainty from sensed data is introduced. …
Identifying Four Year Average Cloud Field Regimes From World Wide Merged Cloud Analysis Dataset By Way Of K-Means Clustering, Stewart G. Almeida
Identifying Four Year Average Cloud Field Regimes From World Wide Merged Cloud Analysis Dataset By Way Of K-Means Clustering, Stewart G. Almeida
Theses and Dissertations
Joint histograms of cloud top height (CTH) and optical depth (OD) are created using the World-Wide Merged Cloud Analysis (WWMCA) dataset over a four year period (2014-2017) to identify average cloud field regimes and assess the application of utilizing the WWMCA dataset with the AFIT Sensor and Scene Emulation Tool (ASSET). Two selected regions encompassing the Florida peninsula and a portion of the Pacific Ocean off the west-central coast of South America are examined over the months of January and July. Cloud field regimes are identified by running generated hourly OD-CTH histograms through k-means clustering, with optimal cluster number ( …
Nonlinear Solution Of The Time Eigenvalue Of A Fast Burst Reactor Using The Finite Volume Method, Stephen H. Baxter
Nonlinear Solution Of The Time Eigenvalue Of A Fast Burst Reactor Using The Finite Volume Method, Stephen H. Baxter
Theses and Dissertations
This effort models fast burst reactors using the one dimensional, one group neutron diffusion equation to solve for the time eigenvalue, a method for which an analytical solution exists against which the numerical results can be verified. An existing solution method is enhanced by the addition of a second order accurate finite volume discretization, which is then used to model two separate fast burst reactors. The results of these models are then compared to the results of previous work, the analytical solution, and existing experimental burst width data for each of the two reactors.
A Comparative Evaluation Of The Fast Optical Pulse Response Of Event-Based Cameras, Tyler J. Brewer
A Comparative Evaluation Of The Fast Optical Pulse Response Of Event-Based Cameras, Tyler J. Brewer
Theses and Dissertations
Event cameras use biologically inspired readout circuit architecture to offer a faster and more efficient method of imaging than traditional frame-based detectors. The asynchronous event reporting circuit timestamps events to 1 microsecond resolution, but latency increases when many pixels are stimulated simultaneously. To characterize this variability, the DAVIS240, DAVIS346, DVXPlorer, and Prophesee Gen3M VGA-CD 1.1 cameras were exposed to single step-function flashes with amplitudes from 9.3-771cd/m2, stimulating from 0.0042-100 of pixels. The Median Absolute Deviation of pixel response times ranged between 0 and 6086µs, increasing with the percent of pixels stimulated (PSP). The number of events generated per …
Strategic Upgrade Scheduling And Portfolio Management To Fortify Contested Networks, Justin L. Anderson
Strategic Upgrade Scheduling And Portfolio Management To Fortify Contested Networks, Justin L. Anderson
Theses and Dissertations
The nuclear command, control, and communication (NC3) network provides an effective deterrent against adversaries by maintaining robust communication between assets, operators, and decision makers. NC3 must receive a series of upgrades to remain an effective deterrent against evolving threats around the globe. Given a contested network and a portfolio of network upgrades, this research seeks an optimal upgrade schedule to maximize network resilience in support of NC3 modernization. Our research contributes a model that solves a budget-constrained network upgrade scheduling problem (NUSP). The NUSP is a defender-attacker-defender tri-level optimization model that achieves fortification via selecting and scheduling network upgrades. The …
Reducing Military Personnel Flight Wait Times Using A Simulation, Matthew D. Cornman
Reducing Military Personnel Flight Wait Times Using A Simulation, Matthew D. Cornman
Theses and Dissertations
A shortage of resources and system failures have put a strain on Military Personnel Flights (MPFs) being able to service their customers in a timely manner. Prolonged customer wait times are becoming a common problem in most MPFs creating problems between the relationship of the customers and leadership. This research uses historical data of an MPF to develop a simulation model of daily operations in an MPF. Subject matter expertise of current MPF operations and resource levels were used to provide a baseline model of the MPF queuing system. The analysis examines the effects of number of Defense Enrollment Eligibility …
Predicting F-16 Cause Code H Micap Hours Using Jmp Regression Analysis, Scott E. Carr
Predicting F-16 Cause Code H Micap Hours Using Jmp Regression Analysis, Scott E. Carr
Theses and Dissertations
Emergency demands for aircraft parts, MICAPs (Mission Impaired Capability Awaiting Parts) are one of the leading issues affecting mission capability supply rates for fighter aircraft. Cause code H MICAPS, those with a known demand level, but no supply available, are particularly troublesome and difficult to resolve. These MICAPS are due to failures by the supply chain to replenish stock levels within acceptable time limits. Numerous studies have identified a clear need for proactive measures to reduce MICAP hours. This would significantly improve aircraft availability. This study uses regression analysis implemented in JMP software to build models with a goal of …
Air Combat Maneuvering Via Operations Research And Artificial Intelligence Methods, James B. Crumpacker
Air Combat Maneuvering Via Operations Research And Artificial Intelligence Methods, James B. Crumpacker
Theses and Dissertations
Within visual range air combat requires rapid, sequential decision-making to survive and defeat the adversary. Fighter pilots spend years perfecting maneuvers for these types of engagements, yet the emergence of unmanned, autonomous vehicle technologies elicits a natural question - can an autonomous unmanned combat aerial vehicle (AUCAV) be imbued with the necessary artificial intelligence to perform air combat maneuvering tasks independently? We formulate and solve the air combat maneuvering problem to examine this question, developing a Markov decision process model to control an AUCAV seeking to destroy a maneuvering adversarial vehicle. An approximate dynamic programming (ADP) approach implementing neural network …
Exploring The Limits Of Strategic Thought: Evaluating How Different Communication Modalities Affect The Nature Of Strategic Decision-Making Using Cognitive Hierarchy, Stephen D. Donnel
Exploring The Limits Of Strategic Thought: Evaluating How Different Communication Modalities Affect The Nature Of Strategic Decision-Making Using Cognitive Hierarchy, Stephen D. Donnel
Theses and Dissertations
This research examines and quantifies the degree to which both information communication modality and the situational complexity affect individuals' ability to process the provided information and determine an effective strategy. Human subject testing herein consists of benign benevolent intervention involving the presentation of a series of strategic situations. For each situation, a participant attempts to identify their best response for a two-player, normal-form game with complete information. In each such game, players seek to maximize their own utility while considering their own actions, their opponent's actions, and each player's respective preferences over outcomes resulting from the possible combinations of actions. …
An Examination Of Potential Training Regression Recognition Algorithms For Pilot Training Next, Alex R. Gaines
An Examination Of Potential Training Regression Recognition Algorithms For Pilot Training Next, Alex R. Gaines
Theses and Dissertations
The initiative to reduce the Air Forces serious pilot shortage lead to the Pilot Training Next (PTN) program. Under PTN, student pilots progress at an individual rate while making increased use of simulator-based training resources. A previous thesis used data from the first PTN class to conceptualize and prototype a student training flight scheduler. This scheduler did not consider training events required to bring students back to achieved levels of performance if in fact that student performance had regressed. This thesis examines three classes of PTN student data to determine whether student regression in training progression can be detected. A …
The Autonomous Attack Aviation Problem, John C. Goodwill
The Autonomous Attack Aviation Problem, John C. Goodwill
Theses and Dissertations
An autonomous unmanned combat aerial vehicle (AUCAV) performing an air-to-ground attack mission must make sequential targeting and routing decisions under uncertainty. We formulate a Markov decision process model of this autonomous attack aviation problem (A3P) and solve it using an approximate dynamic programming (ADP) approach. We develop an approximate policy iteration algorithm that implements a least squares temporal difference learning mechanism to solve the A3P. Basis functions are developed and tested for application within the ADP algorithm. The ADP policy is compared to a benchmark policy, the DROP policy, which is determined by repeatedly solving a deterministic orienteering problem as …
The Impact Of Triage Classification Errors On Military Medical Evacuation System Performance, Emily S. Graves
The Impact Of Triage Classification Errors On Military Medical Evacuation System Performance, Emily S. Graves
Theses and Dissertations
In a deployed environment, evacuation requests of injured personnel are serviced by multiple forms of evacuation including medical evacuation (MEDEVAC) and casualty evacuation (CASEVAC). This thesis focuses on the optimal dispatching policy for MEDEVAC units when triage classification errors and blood transfusion kits are considered. A discounted, infinite-horizon Markov decision process (MDP) model is formulated to analyze the MEDEVAC dispatching problem and determine the optimal policy based on the status of the MEDEVAC units in the system, the priority level of incoming requests, and the locations from which requests originate. A notional, representational scenario based in Azerbaijan is utilized to …
Automated Sentiment Analysis For Personnel Survey Data In The Us Air Force Context, Julia M. Haines
Automated Sentiment Analysis For Personnel Survey Data In The Us Air Force Context, Julia M. Haines
Theses and Dissertations
When surveys are distributed across the Air Force (AF), whether it be an employee engagement survey, a climate survey, or similar, significant resources are put towards the development, distribution and analysis of the survey. However, when open ended questions are included on these surveys, respondent comments are generally underutilized, more often treated as a source for pull-quotes rather than a data source in and of themselves. This is due to a lack of transparency and confidence in the accuracy of machine-aided methods such as sentiment analysis and topic modeling. This confidence reduces further when the text has special context, such …
Allocation Of Scarce Healthcare Resources In A Military Treatment Facility During A Pandemic: A Comparison Of Goal Programming And Portfolio Decision Analysis Methods, Donald B. Hale
Theses and Dissertations
In a pandemic, healthcare decisionmakers face the challenge of allocating critical, but scarce healthcare resources in a dynamic, uncertain environment. Their decisions will not only affect the patients coming to the hospital for treatment, but also the Military Treatment Facility's personnel responsible. The decisionmaker must decide how to allocate these resources to achieve multiple, conflicting objectives under multiple constraints. In response, we propose a methodology for the implementation of both Portfolio Decision Analysis and Goal Programming. The steps of this methodology provide a framework with which the decisionmaker can develop optimal allocation of resources. This framework was then applied to …
Ccsfs/Ksc Total Lightning Warning Radii Optimization For Merlin Using Preexisting Lightning Areas, Kimberly G. Holland
Ccsfs/Ksc Total Lightning Warning Radii Optimization For Merlin Using Preexisting Lightning Areas, Kimberly G. Holland
Theses and Dissertations
The purpose of this research is to optimize lightning warning radii specifications for the 45th Space Wing (45 SW), thus reducing the number of unnecessary warnings that delay ground processing needed for space launch execution at Kennedy Space Center and Cape Canaveral Space Force Station. This thesis sought to answer two key research questions addressing: 1) What radius reduction effectively balances both safety and operations and do reduction recommendations from previous research align with results from the new detection system? 2) What insights can be gained from comparing measurement results for seasonal lightning events as well as lightning types? This …
Improving Air Battle Management Target Assignment Processes Via Approximate Dynamic Programming, Joseph M. Liles Iv
Improving Air Battle Management Target Assignment Processes Via Approximate Dynamic Programming, Joseph M. Liles Iv
Theses and Dissertations
Military air battle managers face many challenges when directing operations in quickly evolving combat scenarios. These scenarios require rapid decisions to engage moving and unpredictable targets. In defensive operations, the success of a sequence of air battle management decisions is reflected by the friendly force's ability to maintain air superiority by defending friendly assets. We develop a Markov decision process (MDP) model of the air battle management (ABM)problem, wherein a set of unmanned combat aerial vehicles (UCAV) is tasked to defend a central asset from cruise missiles that arrive stochastically over time.
Examining Crucial Demographic Trends In General Aviation, Joshua D. Meyer
Examining Crucial Demographic Trends In General Aviation, Joshua D. Meyer
Theses and Dissertations
America's General Aviation sector has witnessed significant demographic shifts since the turn of the century. The number of certified, private pilots, non-fatal aircraft accidents, fatal aircraft accidents, and number of general aviation hours flown are all in decline. Meanwhile, the average age of an American private pilot has increased by several years. All of these factors indicate that the industry is in decline. This study determined via mathematical, linear regression that times relationship to the number of annual, fatal General Aviation accidents and the number of certified private pilots is negative. It also proved that the average age of the …
Analysis Of Functional Responses In Experimental Design, Matthew E. Scherer
Analysis Of Functional Responses In Experimental Design, Matthew E. Scherer
Theses and Dissertations
The growth of sensor streamed data in recent years increases the demand for an analytical technique to properly address data measured continuously. The design and analysis of experiments (DOE) of U.S. Air Force assets are based off of sensor streamed data. Functional data analysis (FDA) is an approach of analyzing data existing over a continuum. This research aids in filling the intersection of FDA and DOE by examining a case study of an experimental design with a functional response in addition to insight on software capabilities in FDA. The case study considers a functional linear model of a whole-plot from …
Bayesian Augmentation Of Cnn-Lstm For Video Classification With Uncertainty Measures, Emmie K. Swize
Bayesian Augmentation Of Cnn-Lstm For Video Classification With Uncertainty Measures, Emmie K. Swize
Theses and Dissertations
The success of Department of Defense (DoD) missions rely heavily on intelligence, surveillance, and reconnaissance (ISR) capabilities, which supply information about the activities and resources of an enemy or adversary. To secure this information, satellites and unmanned aircraft systems collect video data to be classified by either humans or machine learning networks. Traditional automated video classification methods lack measures of uncertainty, meaning the network is unable to identify those cases in which it predictions are made with significant uncertainty. This leads to misclassification, as the traditional network classifies each observation with same amount of certainty, no matter what the observation …
Behavior Of Lightning In Developing Storms, Erick A. Tello
Behavior Of Lightning In Developing Storms, Erick A. Tello
Theses and Dissertations
Air Force weather squadrons issue a warning when lightning activity is observed within 5 nautical miles (NM) of protected areas. Upon receiving this warning, personnel outdoors are expected to pause work and move inside. Studies sponsored by the 45th Weather Squadron (45 WS) have concluded that the 5 NM warning radius can be safely reduced for well-developed storms. This thesis investigates whether radii for storms in early development can also be reduced. Our research develops algorithms to partition lightning sensor data into storms. Next, storms are filtered to their earliest lightning events, and the study calculates distances between successive early …
An Examination Of Civilian Retention In The United States Air Force, William F. Wilson
An Examination Of Civilian Retention In The United States Air Force, William F. Wilson
Theses and Dissertations
The backbone of the United States Air Force is undoubtedly the large civilian workforce that supplements the great work that is accomplished. Many research studies have been conducted on officer and enlisted personnel to ensure that the career fields are properly developed and managed to meet the ever growing demands of the military's varied missions, but no recent studies have focused on the civilian workforce. Striking a balance between new and experienced employees is paramount to success given the ever-changing economic and political landscapes where we find ourselves. The first part of the research uses logistic regression to determine the …
Hazard Mapping For Infrastructure Planning In The Arctic, Christopher I. Amaddio
Hazard Mapping For Infrastructure Planning In The Arctic, Christopher I. Amaddio
Theses and Dissertations
Using modern high-resolution aerial photographs, LiDAR, historical aerial photographs, and facility data, a hazard mapping effort identified risks to infrastructure at Thule Air Base, Greenland, based on visible terrain features, surface hydrology, and slope; the distribution of these risks were then compared to existing foundation damage. The analysis indicated abundant and widespread geotechnical hazards at Thule Air Base and a weak relationship to existing foundation damage that requires more research to understand. The resulting hazard maps provide a critical tool for risk assessment and planning as well as a model for other locations to follow.
Model Based Systems Engineering Demonstrator For Air Worthiness With Performance Data Of Department Of Defense Rotorcraft, Bretton M. Bethel
Model Based Systems Engineering Demonstrator For Air Worthiness With Performance Data Of Department Of Defense Rotorcraft, Bretton M. Bethel
Theses and Dissertations
Airworthiness is a process of certifying that an aircraft can be safety operated within specified bounds. This process is essential to ensuring the safety of the aircraft, its personnel, and the surrounding assets. A Model-Based Systems Engineering (MBSE) approach can be utilized as a method to improve the airworthiness process. MBSE is the methodology of creating and utilizing domain models as a means of exchanging and presenting information for a wide variety of disciplines to understand and replacing previous document-based exchange. The objective of this research is to develop a reference architecture with a MBSE approach to perform the airworthiness …
Re-Aerosolization Of Dense Metal Oxide Simulating Radiological Contamination From Military Clothing, Joseph M. Chapman
Re-Aerosolization Of Dense Metal Oxide Simulating Radiological Contamination From Military Clothing, Joseph M. Chapman
Theses and Dissertations
Radiological contamination from nuclear accidents or the terrorist use of a Radiological Dispersal Device (RDD) are events that first responders must be prepared for. It is currently assumed that removal of the victims clothing will remove 80-90 of contamination. Many RDD radioisotopes produce dense aerosols that would then contaminate victim clothing and re-aerosolize during clothing removal. A series of experiments were conducted during which clothing was contaminated with a dense aerosol simulating the radioisotope of Strontium 90. Compared to background, there was statistically significant re-aerosolization from the clothing. This demonstrates inhalation hazards from re-aerosolization of RDD contamination.
An Analysis Of Various Hydrogen Production Methods For Fleet Vehicle Fuel, Eugene J. Denezza Ii
An Analysis Of Various Hydrogen Production Methods For Fleet Vehicle Fuel, Eugene J. Denezza Ii
Theses and Dissertations
As conflict, the environment, and politics cause changes around the world, the United States Air Force is pursuing a diversification of drop-in and alternative fuel sources. Hydrogen fuel cells for vehicles are gaining popularity worldwide. Yet, how to best produce hydrogen gas still remains a question. This thesis will provide an overview of various hydrogen production methods and their respective environmental impacts, costs, efficiencies, and viability; and will perform sensitivity analysis to determine an optimal solution. The optimal production method is Thermolysis followed by Steam Reformation of Landfill or Natural Gas, Coal Gasification, and PEM Electrolysis. Based on varying requirements …
A Fuzzy Framework For The Air Force Mission Dependency Index, Devin M. Depalmer
A Fuzzy Framework For The Air Force Mission Dependency Index, Devin M. Depalmer
Theses and Dissertations
AFIMSC completed an MDI modernization to support better risk-based decision-making by utilizing tactical mission-owner knowledge to quantify the relationship between facilities and the missions they enable. The resulting facility-mission risk scores leave room for improvement for better use of their intended purposes due to (1) the vulnerability of cognitive biases affecting survey responses due to the use of a traditional risk matrix (2) the lack of resolution between scores from risk ties and (3) the failure to include information from the operational and strategic organizational hierarchy level. This research addresses these concerns through the novel implementation of a fuzzy logic …
Application Of Game Theory Based Design To U.S. Space Systems, Benjamin C. Donohoo
Application Of Game Theory Based Design To U.S. Space Systems, Benjamin C. Donohoo
Theses and Dissertations
Modern defense systems are designed to static sets of requirements and specifications. This process has worked well in the past but fails to account for the strategic interdependence of design choices made prior to operating systems. However, as the world becomes increasingly competitive, and as the space domain becomes increasingly congested and contested, such interdependence of design can be described using Game Theory. Game Theory is the mathematical study of strategy, actions and payoffs between rational, self-interested actors. Limited extant research has applied Game Theory to system design but focused on a single system being designed cooperatively within a single …
Costs And Benefits Of Physical Therapy Program Implementation For Air Force Fighter Pilots, Christian G. Erneston
Costs And Benefits Of Physical Therapy Program Implementation For Air Force Fighter Pilots, Christian G. Erneston
Theses and Dissertations
Air Force fighter pilots face risks associated with neck and spine injuries sustained while operating fighter aircraft. Studies from the flying and medical communities indicate that muscle-strengthening prehabilitative care may decrease the risk of flying related injuries in high performance aircraft pilots. For this reason, the U.S. Air Force provided $24.9M to implement the Optimizing the Human Weapon System (OHWS) program. The program provides physical therapy and strength training to fighter pilots in participating units at twenty-one Air Force bases with the intent of reducing injury rates and time out of the cockpit. From a healthcare perspective there is interest …
Usaf Fms Manpower Analysis: Manpower Ratios And Linear Regression, Carlos A. Esguerra
Usaf Fms Manpower Analysis: Manpower Ratios And Linear Regression, Carlos A. Esguerra
Theses and Dissertations
This research studies the relationships between Air Force Foreign Military Sales (FMS) case factors and manpower authorizations. The Air Force FMS program has seen consistent annual increases in sales since 2017 and average annual growth of 7 percent since 2006. Manpower is a key factor in the continued success of the FMS program. The need to predict future manpower requirements and the lack of prior research in this area motivates this exploratory analysis to determine which FMS case factors are potential candidates to predict manpower needs. An initial comparison analysis of the available FMS case data was conducted, followed by …