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Full-Text Articles in Entire DC Network
Development Of A Testbed For Foot Mounted Based Pedestrian Dead Reckoning (Pdr) Systems, Jordan E. Eldridge
Development Of A Testbed For Foot Mounted Based Pedestrian Dead Reckoning (Pdr) Systems, Jordan E. Eldridge
Theses and Dissertations
Over the last several years of research into the field of Pedestrian Dead Reckoning (PDR), there have been varying degrees of success in providing a viable individual navigation system. The PDR solutions developed utilize everything from a single Inertial Measurement Units (IMU) to several IMUs with additional sensors. One specific PDR solution identified that by utilizing a micro-mechanical Inertial Measurement Unit (IMU) on each foot (along with the application of Zero Velocity Updates (ZUPT) and foot-to-foot range measurements) a reliable method of PDR tracking could be accomplished. Their study concludes that further evaluation is required for this foot-mounted solution to …
Stereo Camera Calibrations With Optical Flow, Joshua D. Larson
Stereo Camera Calibrations With Optical Flow, Joshua D. Larson
Theses and Dissertations
Remotely Piloted Aircraft (RPA) are currently unable to refuel mid-air due to the large communication delays between their operators and the aircraft. AAR seeks to address this problem by reducing the communication delay to a fast line-of-sight signal between the tanker and the RPA. Current proposals for AAR utilize stereo cameras to estimate where the receiving aircraft is relative to the tanker, but require accurate calibrations for accurate location estimates of the receiver. This paper improves the accuracy of this calibration by improving three components of it: increasing the quantity of intrinsic calibration data with CNN preprocessing, improving the quality …
Low-Cost Terrestrial Demonstration Of Autonomous Satellite Proximity Operations, Zackary R. Hewitt
Low-Cost Terrestrial Demonstration Of Autonomous Satellite Proximity Operations, Zackary R. Hewitt
Theses and Dissertations
The lack of satellite servicing capabilities significantly impacts the development and operation of current orbital assets. With autonomous solutions under consideration for servicing, the purpose of this research is to build and validate a low-cost hardware platform to expedite the development of autonomous satellite proximity operations. This research aims to bridge the gap between simulation and existing higher fidelity hardware testing with an affordable alternative. An omnidirectional variant of the commercially available TurtleBot3 mobile robot is presented as a 3-DOF testbed that demonstrates a satellite servicing inspection scenario. Reference trajectories for the scenario are generated via optimal control using the …
Application Of The Monte-Carlo Tree Search To Multi-Action Turn-Based Games With Hidden Information, Connor M. Pipan
Application Of The Monte-Carlo Tree Search To Multi-Action Turn-Based Games With Hidden Information, Connor M. Pipan
Theses and Dissertations
Traditional search algorithms struggle when applied to complex multi-action turn-based games. The introduction of hidden information further increases domain complexity. The Monte-Carlo Tree Search (MCTS) algorithm has previously been applied to multi-action turn-based games, but not multi-action turn-based games with hidden information. This thesis compares several Monte Carlo Tree Search (MCTS) extensions (Determinized/Perfect Information Monte Carlo, Multi-Observer Information Set MCTS, and Belief State MCTS) in TUBSTAP, an open-source multi-action turn-based game, modified to include hidden information via fog-of-war.
Optimizing A Bank Of Kalman Filters For Navigation Integrity, Luis E. Sepulveda
Optimizing A Bank Of Kalman Filters For Navigation Integrity, Luis E. Sepulveda
Theses and Dissertations
Alternative navigation is an area of research which employs a variety of sensor technologies to provide a navigation solution in Global Navigation Satellite System degraded or denied environments. The Autonomy and Navigation Technology Center at the Air Force Institute of Technology has recently developed the Autonomous and Resilient Management of All-source Sensors (ARMAS) navigation framework which utilizes an array of Kalman Filters to provide a navigation solution resilient to sensor failures. The Kalman Filter array size increases exponentially as system sensors and detectable faults are scaled up, which in turn increases the computational power required to run ARMAS in areal-world …
Spatially Separable Blind Deconvolution Of Long Exposure Astronomical Imagery, Justin S. Lee
Spatially Separable Blind Deconvolution Of Long Exposure Astronomical Imagery, Justin S. Lee
Theses and Dissertations
In this thesis, a spatially separable blind deconvolution algorithm is demonstrated that achieves a significantly faster processing time and superior sensitivity when processing long-exposure image data of unresolvable objects from a ground-based telescope. The proposed approach takes advantage of the structure of the long exposure point spread functions radial symmetric characteristics to approximate it as a product of one dimensional horizontal and vertical intensity distributions. Objects at geosynchronous or geostationary orbit also can be well approximated as being spatially separable as they are, in general non-resolvable. The algorithms performance is measured by computing the mean-squared error compared with the true …
Anomaly Detection And Encrypted Programming Forensics For Automation Controllers, Robert W. Mellish
Anomaly Detection And Encrypted Programming Forensics For Automation Controllers, Robert W. Mellish
Theses and Dissertations
Securing the critical infrastructure of the United States is of utmost importance in ensuring the security of the nation. To secure this complex system a structured approach such as the NIST Cybersecurity framework is used, but systems are only as secure as the sum of their parts. Understanding the capabilities of the individual devices, developing tools to help detect misoperations, and providing forensic evidence for incidence response are all essential to mitigating risk. This thesis examines the SEL-3505 RTAC to demonstrate the importance of existing security capabilities as well as creating new processes and tools to support the NIST Framework. …
Automated Network Exploitation Utilizing Bayesian Decision Networks, Graeme M. Roberts
Automated Network Exploitation Utilizing Bayesian Decision Networks, Graeme M. Roberts
Theses and Dissertations
Computer Network Exploitation (CNE) is the process of using tactics and techniques to penetrate computer systems and networks in order to achieve desired effects. It is currently a manual process requiring significant experience and time that are in limited supply. This thesis presents the Automated Network Discovery and Exploitation System (ANDES) which demonstrates that it is feasible to automate the CNE process. The uniqueness of ANDES is the use of Bayesian decision networks to represent the CNE domain and subject matter expert knowledge. ANDES conducts multiple execution cycles, which build upon previous action results. Cycles begin by modeling the current …
Improving Text Classification With Semantic Information, Joshua H. White
Improving Text Classification With Semantic Information, Joshua H. White
Theses and Dissertations
The Air Force contracts a variety of positions, from Information Technology to maintenance services. There is currently no automated way to verify that quotes for services are reasonably priced. Small training data sets and word sense ambiguity are challenges that such a tool would encounter, and additional semantic information could help. This thesis hypothesizes that leveraging a semantic network could improve text-based classification. This thesis uses information from ConceptNet to augment a Naive Bayes Classifier. The leveraged semantic information would add relevant words from the category domain to the model that did not appear in the training data. The experiment …
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 …
A Comparison Of Sporadic-E Occurrence Rates Using Ionosondes And Gps Radio Occultation Measurements, Rodney A. Carmona Jr.
A Comparison Of Sporadic-E Occurrence Rates Using Ionosondes And Gps Radio Occultation Measurements, Rodney A. Carmona Jr.
Theses and Dissertations
Sporadic-E (Es) occurrence rates from Global Position Satellite radio occultation (GPS-RO) measurements have shown to vary by nearly an order of magnitude between studies, motivating a comparison with ground-based measurements. In an attempt to find an accurate GPS-RO technique for detecting Es formation, occurrence rates derived using five previously developed GPS-RO techniques are compared to ionosonde measurements over an eight-year period from 2010-2017. GPS-RO measurements within 170 km of a ionosonde site are used to calculate Es occurrence rates and compared to the ground-truth ionosonde measurements. Each technique is compared individually for each ionosonde site and then combined to determine …
Meta-Heuristic Optimization Methods For Quaternion-Valued Neural Networks, Jeremiah P. Bill
Meta-Heuristic Optimization Methods For Quaternion-Valued Neural Networks, Jeremiah P. Bill
Theses and Dissertations
In recent years, real-valued neural networks have demonstrated promising, and often striking, results across a broad range of domains. This has driven a surge of applications utilizing high-dimensional datasets. While many techniques exist to alleviate issues of high-dimensionality, they all induce a cost in terms of network size or computational runtime. This work examines the use of quaternions, a form of hypercomplex numbers, in neural networks. The constructed networks demonstrate the ability of quaternions to encode high-dimensional data in an efficient neural network structure, showing that hypercomplex neural networks reduce the number of total trainable parameters compared to their real-valued …
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 …
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 …
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. …
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 …
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 …
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 …
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 …
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 …
Utilizing Model Based Systems Engineering To Identify Safety Critical Functions In Airworthiness Certification, Jeffrey C. King
Utilizing Model Based Systems Engineering To Identify Safety Critical Functions In Airworthiness Certification, Jeffrey C. King
Theses and Dissertations
Modern aircraft are complex systems with numerous interacting hardware and software components. To minimize any safety mishaps during operations, new aircraft designs and modifications must go through an airworthiness certification. The current United States Air Force (USAF) airworthiness certification process, captured in MIL-HDBK-516C, is time-consuming and manpower intensive due to extensive documentation. To minimize inefficiencies of this document-based approach, this thesis examined model-based systems engineering (MBSE) to support Safety Critical Function (SCF) thread analysis against criteria found in Section 15 of MIL-HDBK-516C. Within this scope, the research identified an SCF domain-specific profile and style guide using the Systems Modeling Language …
Evaluating The Impact Of Culture On Customer Satisfaction For Fms Projects, Yaquari A. Adams Ii
Evaluating The Impact Of Culture On Customer Satisfaction For Fms Projects, Yaquari A. Adams Ii
Theses and Dissertations
The cost, time, and quality pillars of the iron triangle in project management are often considered the most important factors for managers to consider when striving to achieve project success. However, recent literature suggests customer satisfaction and end-user benefit are the most important elements to prioritize during project development. This research analyzes the Air Force Security Assistance Center Construction Division and Foreign Military Sales (FMS) joint construction operations in relation to two Project Management Body of Knowledge (PMBOK) knowledge areas, project stakeholder management and project risk management. Project stakeholder management is addressed by identifying the relationship between cultural competency and …
Optimizing Cost And Performance Of Infrastrucure Alternatives At Contingency Bases In A Hub-And-Spoke Network, Kyle J. Rodriguez
Optimizing Cost And Performance Of Infrastrucure Alternatives At Contingency Bases In A Hub-And-Spoke Network, Kyle J. Rodriguez
Theses and Dissertations
Military contingency bases require substantial resources and funding sustain and are often not connected to an infrastructure grid. Infrastructure assets produce the required outputs for sustainment, but are often expensive and inefficient, producing a significant logistical burden. With the increasing near-peer threats of opposing military forces, there is a need for more self-sufficient contingency bases with alternatives that reduce resources usage and the cost of sustainment. Accordingly, the goal of this research is to develop an optimization model capable of selecting infrastructure alternative combinations that minimize the overall resource usage and cost of sustainment at the contingency base level.
Comparison Of Decision Analysis Methods For A Cubesat Propulsion System, Jared L. Pilcher
Comparison Of Decision Analysis Methods For A Cubesat Propulsion System, Jared L. Pilcher
Theses and Dissertations
Low Earth Orbit (LEO) is becoming an increasingly congested orbital regime. As a result, propulsion systems on CubeSats are becoming a more desirable feature to provide them with collision avoidance capabilities. To date, there have been very few CubeSat launches with a propulsion system on them. Due to the relatively high cost of a propulsion system compared to the budget of small educational organizations, a decision analysis model is needed so that these organizations can make the best decision between whether to purchase a Commercial-Off-The-Shelf (COTS) product or to develop one within the organization. This research applies three decision analysis …
Crop Circles In The Corn Belt: A Farm-Scale Model To Curb Future Crop Yield Loss With Blended Policy-Structural Adaptations, Daniel Ress
Theses and Dissertations
In today's rainfed agricultural regions farmers reliably produce marketable yields without the need for irrigation technology or specific planting policies. However, climate change is expected to challenge global food security. As a result, farmers might seek adaptation strategies. This research investigates the spatiotemporal suitability of blended policy-structural adaptations to reduce yield losses in Greene County, Ohio. A crop-water model is used to calibrate and generate field-scale yield predictions. The resultant framework holds the potential to inform farmer and county-level decision making under future climate uncertainty, and it illustrates the tradeoffs between adaptation cost and yield security.
Operational Carbon Footprint Of The U.S. Water Sector’S Energy Consumption, Louis J. Zib Iii
Operational Carbon Footprint Of The U.S. Water Sector’S Energy Consumption, Louis J. Zib Iii
Theses and Dissertations
Accounting of energy-related GHG emissions in the water sector have largely been conducted at single utilities or cities and rarely at a regional or country scale. In this study, we assess the carbon footprints of operational energy use for 76 wastewater utilities and 64 water utilities across the United States. Additionally, we investigate water-related GHG emissions at a sub-annual scale through three case cities to understand how GHG emissions change at the monthly scale. We estimate the total drinking water and wastewater GHG emissions associated with electricity, biogas, natural gas, and fuel oil consumption across the United States to be …
Analysis Of Pollution Prevention Business Case Analyses, Erwin A. Spencer Jr.
Analysis Of Pollution Prevention Business Case Analyses, Erwin A. Spencer Jr.
Theses and Dissertations
The purpose of this research is to improve the Business Case Analysis (BCA) process in the context of pollution prevention. The research will inform guidance, training, and policy recommendations. Using grounded theory methods allowed us to gather qualitative data directly from participants actively involved in pollution prevention projects. In addition to answering several research questions, the results of the research informed the design of a tool to help government and contractor personnel agree on what constitutes a high-quality BCA. This research has implications for DoD decision making and future studies in environmental cost analysis.
Performance Analysis Of Long-Term Evoluution Signals In Passive Bistatic Radar Applications Using Reduced Dimension Space-Time Adaptive Processing Techniques, Sureshan Suntharalingam
Performance Analysis Of Long-Term Evoluution Signals In Passive Bistatic Radar Applications Using Reduced Dimension Space-Time Adaptive Processing Techniques, Sureshan Suntharalingam
Theses and Dissertations
Widespread availability of long term evolution (LTE) signals makes them potential for use in passive bistatic radar (PBR) applications. However, their utility in such applications is yet to be fully explored. This research focuses on the key LTE signal attributes, such as subcarrier modulation schemes and bandwidth, and their effect on PBR application. space-time adaptive processing (STAP) concepts, both full dimension STAP (FD-STAP) reduced dimension STAP (RD-STAP), were employed to evaluate and compare the effects of varying these signal attributes, in terms of signal to interference-plus-noise ratio (SINR) loss metrics. Simulation results concluded that decreasing LTE signal's bandwidth and increasing …
The Impact Of Threat Levels At The Casualty Collection Point On Military Medical Evacuation System Performance, Nathaniel C. Dennie
The Impact Of Threat Levels At The Casualty Collection Point On Military Medical Evacuation System Performance, Nathaniel C. Dennie
Theses and Dissertations
One of the primary duties of the Military Health System is to provide effective and efficient medical evacuation (MEDEVAC) to injured battlefield personnel. To accomplish this, military medical planners seek to develop high-quality dispatching policies that dictate how deployed MEDEVAC assets are utilized throughout combat operations. This thesis seeks to determine dispatching policies that improve the performance of the MEDEVAC system. A discounted, infinite-horizon continuous-time Markov decision process (MDP) model is developed to examine the MEDEVAC dispatching problem. The model incorporates problem features that are not considered under the current dispatching policy (e.g., myopic policy), which tasks the closest-available MEDEVAC …