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Passive Load Testing For Evaluation Of Electromechanical Actuators, Jeremiah R. Hoffman
Passive Load Testing For Evaluation Of Electromechanical Actuators, Jeremiah R. Hoffman
Theses and Dissertations
While aircraft control surfaces traditionally use hydraulic actuators, electromechanical actuators (EMAs) are interesting as they have potential to be lighter, lower maintenance, and more robust. However, EMAs require more research regarding force-fight characteristics, power requirements, performance specifications, and more. The Air Force Research Laboratory is conducting some of this research, and operates a test rig which provides a passive load to a pair of EMAs. This rig is designed for simple test profiles for investigating force-fight; if it could be used to represent actual flight profiles, the rig could accommodate a wider variety of tests. The focus of this project …
Mitigating The Effects Of Cyber Attacks And Human Control In An Autonomous Intersection, Karl C. Bentjen
Mitigating The Effects Of Cyber Attacks And Human Control In An Autonomous Intersection, Karl C. Bentjen
Theses and Dissertations
Widespread use of fully autonomous vehicles is near. However, the desire for a human to maintain control, even if limited, of a vehicle will likely never fully subside. Protocols to safely and efficiently manage reservation-based intersections with a mixture of fully autonomous, semi-autonomous, and non-autonomous vehicles exist such as AIM, SemiAIM, and H-AIM. Missing from these protocols is persistent human control of semi-autonomous vehicles in approaching and navigating autonomous intersections without the use of traditional signals. This thesis offers a proof-of-concept of a reservation-based protocol with necessary extensions required for human control in semi-autonomous vehicles. Desired is a protocol that …
Pattern-Of-Life Modeling Using Data Leakage In Smart Homes, Steven M. Beyer
Pattern-Of-Life Modeling Using Data Leakage In Smart Homes, Steven M. Beyer
Theses and Dissertations
This work investigates data leakage in smart homes by providing a Smart Home Automation Architecture (SHAA) and a device classifier and pattern-of-life analysis tool, CITIoT (Classify, Identify, and Track Internet of things). CITIoT was able to capture traffic from SHAA and classify 17 of 18 devices, identify 95% of the events that occurred, and track when users were home or away with near 100% accuracy. Additionally, a mitigation tool, MIoTL (Mitigation of IoT Leakage) is provided to defend against smart home data leakage. With mitigation, CITIoT was unable to identify motion and camera devices and was inundated with an average …
Behavior Flexibility For Autonomous Unmanned Aerial Systems, Taylor B. Bodin
Behavior Flexibility For Autonomous Unmanned Aerial Systems, Taylor B. Bodin
Theses and Dissertations
Autonomous unmanned aerial systems (UAS) could supplement and eventually subsume a substantial portion of the mission set currently executed by remote pilots, making UAS more robust, responsive, and numerous than permitted by teleoperation alone. Unfortunately, the development of robust autonomous systems is difficult, costly, and time-consuming. Furthermore, the resulting systems often make little reuse of proven software components and offer limited adaptability for new tasks. This work presents a development platform for UAS which promotes behavioral flexibility. The platform incorporates the Unified Behavior Framework (a modular, extensible autonomy framework), the Robotic Operating System (a RSF), and PX4 (an open- source …
Estimating Defensive Cyber Operator Decision Confidence, Markus M. Borneman
Estimating Defensive Cyber Operator Decision Confidence, Markus M. Borneman
Theses and Dissertations
As technology continues to advance the domain of cyber defense, signature and heuristic detection mechanisms continue to require human operators to make judgements about the correctness of machine decisions. Human cyber defense operators rely on their experience, expertise, and understanding of network security, when conducting cyber-based investigations, in order to detect and respond to cyber alerts. Ever growing quantities of cyber alerts and network traffic, coupled with systemic manpower issues, mean no one has the time to review or change decisions made by operators. Since these cyber alert decisions ultimately do not get reviewed again, an inaccurate decision could cause …
Progressive Network Deployment, Performance, And Control With Software-Defined Networking, Daniel J. Casey
Progressive Network Deployment, Performance, And Control With Software-Defined Networking, Daniel J. Casey
Theses and Dissertations
The inflexible nature of traditional computer networks has led to tightly-integrated systems that are inherently difficult to manage and secure. New designs move low-level network control into software creating software-defined networks (SDN). Augmenting an existing network with these enhancements can be expensive and complex. This research investigates solutions to these problems. It is hypothesized that an add-on device, or "shim" could be used to make a traditional switch behave as an OpenFlow SDN switch while maintaining reasonable performance. A design prototype is found to cause approximately 1.5% reduction in throughput for one ow and less than double increase in latency, …
Methods Of Reverse Engineering A Bitstream For Field Programmable Gate Array Protection, Daniel J. Celebucki
Methods Of Reverse Engineering A Bitstream For Field Programmable Gate Array Protection, Daniel J. Celebucki
Theses and Dissertations
Field Programmable Gate Arrays (FPGAs) are found in numerous industries including consumer electronics, automotive, military and aerospace, and critical infrastructure. The ability to be reprogrammed as well as large computational power and relatively low price make them a good fit for low-volume applications that cannot justify the Non-Recurring Engineering (NRE) costs associated with producing Application-Specific Integrated Circuits (ASICs). FPGAs however, have seen a variety of security issues stemming from the fact that their configuration files are not inherently protected. This research assesses the feasibility of reverse engineering the bitstream format for a previously unexplored FPGA, as well as the utilization …
Assured Android Execution Environments, Brandon P. Froberg
Assured Android Execution Environments, Brandon P. Froberg
Theses and Dissertations
Current cybersecurity best practices, techniques, tactics and procedures are insufficient to ensure the protection of Android systems. Software tools leveraging formal methods use mathematical means to assure both a design and implementation for a system and these methods can be used to provide security assurances. The goal of this research is to determine methods of assuring isolation when executing Android software in a contained environment. Specifically, this research demonstrates security properties relevant to Android software containers can be formally captured and validated, and that an implementation can be formally verified to satisfy a corresponding specification. A three-stage methodology called "The …
An Exploration Of Error-Correcting Codes For Use In Noise-Prone Satellite Environments, Min W. Kang
An Exploration Of Error-Correcting Codes For Use In Noise-Prone Satellite Environments, Min W. Kang
Theses and Dissertations
Satellites are crucial for the modern world to function properly as they provide Global Navigation Satellite System (GNSS) and global communication. However, the data that is stored on these satellites can be corrupted by the radiation found in space, and its bits can be improperly flipped. In the past, Forward Error Correction (FEC) algorithms were selected based on their strength and implemented to correct these bit flips back to their original values. This thesis seeks to determine if the strength of the FEC algorithms Reed Solomon (RS) code and Reed Solomon Product Code (RSPC) directly translates to their effectiveness. These …
Radio Tomographic Imaging Using A Modified Maximum Likelihood Estimator For Image Reconstruction In Various Environments, Antwon R. Gallagher
Radio Tomographic Imaging Using A Modified Maximum Likelihood Estimator For Image Reconstruction In Various Environments, Antwon R. Gallagher
Theses and Dissertations
Radio Tomographic Imaging (RTI) is an emerging Device-Free Passive Localization (DFPL) technology. Radio Tomographic Imaging (RTI) involves using a set of small low cost wireless transceivers to create a Wireless Sensor Network (WSN) around an Area of Interest (AoI). Furthermore, the Received Signal Strength (RSS) between transceiver pairs is utilized to reconstruct an image from the signal attenuation caused by an object disrupting the links. This image can then be utilized for multiple applications ranging from localization to target detection and tracking. This enhances the importance of image resolution in order to capture the actual size of the objects as …
Special Perturbations On The Jetson Tx1 And Tx2 Computers, Tyler M. Moore
Special Perturbations On The Jetson Tx1 And Tx2 Computers, Tyler M. Moore
Theses and Dissertations
Simplified General Perturbations Number 4 (SGP4) has been the traditional algorithm for performing Orbit Determination (OD) onboard orbiting spacecraft. However, the recent rise of high-performance computers with low Size, Weight, and Power (SWAP) factors has provided the opportunity to use Special Perturbations (SP), a more accurate algorithm to perform onboard OD. This research evaluates the most efficient way to implement SP on NVIDIA’s Jetson TX series of integrated Graphical Processing Units (GPUs). An initial serial version was implemented on the Jetson TX1 and TX2's Central Processing Units (CPUs). The runtimes of the initial version are the benchmark that the runtimes …
Digital Forensics Event Graph Reconstruction, Daniel J. Schelkoph
Digital Forensics Event Graph Reconstruction, Daniel J. Schelkoph
Theses and Dissertations
Ontological data representation and data normalization can provide a structured way to correlate digital artifacts. This can reduce the amount of data that a forensics examiner needs to process in order to understand the sequence of events that happened on the system. However, ontology processing suffers from large disk consumption and a high computational cost. This paper presents Property Graph Event Reconstruction (PGER), a novel data normalization and event correlation system that leverages a native graph database to improve the speed of queries common in ontological data. PGER reduces the processing time of event correlation grammars and maintains accuracy over …
Characterization Of Atd And Human Responses To -Gz Accelerative Input, Joe R. Berry
Characterization Of Atd And Human Responses To -Gz Accelerative Input, Joe R. Berry
Theses and Dissertations
Modern Helmet Mounted Displays (HMD) provide pilots with increased operational capabilities that are essential. Increasing HMD mass in addition to the Air Force’s (AF) expanded range of accepted pilot size increases the risk for neck injuries during ejection. This increase drove Parr et al. (2014) to develop improved neck injury criteria, the MANIC, that increases objective interpretation of ejection system qualification testing results and provides early input to HMD and escape system design. The criteria’s defined human risk curves provide clear implementation guidance for the MANIC with the Air Force Life Cycle Management Center’s (AFLCMC) requirement for ejection systems to …
A Method To Determine The Viability Of Photovoltaic Systems In Various Climate Regions, Joseph A. Applebee
A Method To Determine The Viability Of Photovoltaic Systems In Various Climate Regions, Joseph A. Applebee
Theses and Dissertations
The purpose of this study is to manufacture and disseminate 37 photovoltaic test systems which will be located at various United States Air Force installations worldwide. The Air Force's goals in renewable energy are to determine the potential for systems to aid in promoting resiliency for an installation's energy demands. The test systems are designed to collect climate and power production data from each test site and associated photovoltaic cells. The overall goal of the test system data collection is to determine the correlation between power output of photovoltaic panels and the associated geographic region climate classification. This study does …
Analysis Of Temperature And Humidity Effects On Horizontal Photovoltaic Panels, Corey J. Booker
Analysis Of Temperature And Humidity Effects On Horizontal Photovoltaic Panels, Corey J. Booker
Theses and Dissertations
The United States Air Force seeks to address power grid vulnerability and bolster energy resilience through the use of renewable energy sources. Air Force Institute of Technology engineers designed and manufactured control systems to monitor power production from the most widely-used silicon-based solar cells at 38 testing locations around the globe spanning the majority of climate types. Researchers conducted multivariate regression analysis to establish a statistical relationship between photovoltaic power output, ambient temperature, and humidity pertaining to monocrystalline and polycrystalline photovoltaic panels. Formulated models first characterized power output globally, then by specific climate type with general inaccuracy. Location-specific models are …
Cybersecurity Assessment And Mitigation Stochastic Model, Matthew W. Davis
Cybersecurity Assessment And Mitigation Stochastic Model, Matthew W. Davis
Theses and Dissertations
With numerous cybersecurity incidents and vulnerability concerns in an increasingly contested cyber warfighting environment, the Department of Defense (DoD) has mandated cybersecurity assessment and authorization of all major weapon systems (MWS) before their use. In response to this direction, the Air Force Life Cycle Management Center (AFLCMC) created the Platform Information Technology Assessment and Authorization (PIT A&A) Process. Modeled after the NIST Risk Management Framework (RMF), this process applies a risk-based approach to cybersecurity with the goal of identifying risks and mitigating vulnerabilities in MWS. Within this work, a stochastic model of the PIT A&A Process is presented with an …
Stabilized Rpa Flight In Building Proximity Operations, Michael M. Kaniut
Stabilized Rpa Flight In Building Proximity Operations, Michael M. Kaniut
Theses and Dissertations
The thesis seeks a solution to the requirement for a highly reliable and capable Unmanned Air Vehicle (UAV) to support a wide array of missions and applications that require close proximity flight to structures. The scope of the project includes the drafting of a concept of operations (CONOPs) describing how the mission requirements might be met using the sensor, operators, and air vehicle described here in. The demonstration of the wall-following section of that CONOPs is performed by cart testing a custom algorithm and evaluating its ability to react to its environment. Finally, a flight test was performed to characterize …
Air Force Officer Attrition: An Ecconometric Analysis, Jacob T. Elliot
Air Force Officer Attrition: An Ecconometric Analysis, Jacob T. Elliot
Theses and Dissertations
Many organizations are concerned, and struggle, with personnel management. Training personnel is expensive, so there is a high emphasis on understanding why and anticipating when individuals leave an organization. The military is no exception. Moreover, the military is strictly hierarchical and must grow all its leaders, making retention all the more vital. Intuition holds that there is a relationship between the economic environment and personnel attrition rates in the military (e.g. when the economy is bad, attrition is low). This study investigates that relationship in a more formal manner. Specifically, this study conducts an econometric analysis of U.S. Air Force …
Satellite Communications In The V And W Band: Tropospheric Effects, Bertus A. Shelters
Satellite Communications In The V And W Band: Tropospheric Effects, Bertus A. Shelters
Theses and Dissertations
An investigation into the use of Weather Cubes compiled by the atmospheric characterization package, Laser Environmental Effects Definition and Reference (LEEDR), to develop accurate, long-term attenuation statistics for link-budget analysis is presented. A Weather Cube is a three-dimensional mesh of numerical weather prediction (NWP) data plus LEEDR calculations that allows for the quantification of rain, cloud, aerosol, and molecular effects at any UV to RF wavelength on any path contained within the cube. The development of this methodology is motivated by the potential use of V (40-75 GHz) and W (75-110 GHz) band frequencies for the satellite communication application, as …
Near Earth Space Object Detection Utilizing Parallax As Multi-Hypothesis Test Criterion, Joseph C. Tompkins
Near Earth Space Object Detection Utilizing Parallax As Multi-Hypothesis Test Criterion, Joseph C. Tompkins
Theses and Dissertations
The US Strategic Command (USSTRATCOM) operated Space Surveillance Network (SSN) is tasked with Space Situational Awareness (SSA) for the US military. This system is made up of Electro-Optic sensors such as the Space Surveillance Telescope (SST) and Ground-based Electro-Optical Deep Space Surveillance (GEODSS) as well as RADAR based sensors such as the Space Fence. While Lockheed Martin’s Space Fence is very adept at detecting & tracking objects in Low Earth Orbit (LEO) below 3000 Km in height [1], gaps remain in the tracking of Resident Space Objects (RSO’s) in Geosynchronous Orbits (GEO) due to limitations associated with the implementation of …
Cyber Data Anomaly Detection Using Autoencoder Neural Networks, Spencer A. Butt
Cyber Data Anomaly Detection Using Autoencoder Neural Networks, Spencer A. Butt
Theses and Dissertations
The Department of Defense requires a secure presence in the cyber domain to successfully execute its stated mission of deterring war and protecting the security of the United States. With potentially millions of logged network events occurring on defended networks daily, a limited staff of cyber analysts require the capability to identify novel network actions for security adjudication. The detection methodology proposed uses an autoencoder neural network optimized via design of experiments for the identification of anomalous network events. Once trained, each logged network event is analyzed by the neural network and assigned an outlier score. The network events with …
Parametric Survival Analysis Of Us Air Force Rated Officer Retention, Jacob R. Lindell
Parametric Survival Analysis Of Us Air Force Rated Officer Retention, Jacob R. Lindell
Theses and Dissertations
Personnel retention is a very important topic in both the private and public sectors. Not only do companies need to make sure they have the right people, they need to have the right amount of people. Within the public sector, specifically the US Air Force, maintaining appropriate manning comes in two phases; bringing in the right amount of people each year, and retaining enough people from year to year. These two aspects go hand in hand; if the Air Force knows how many people they will lose in a given year, they can bring in the exact number of people …
Text Classification Of Installation Support Contract Topic Models For Category Management, William C. Sevier
Text Classification Of Installation Support Contract Topic Models For Category Management, William C. Sevier
Theses and Dissertations
Air Force Installation Contracting Agency manages nearly 18 percent of total Air Force spend, equating to approximately 57 billion dollars. To improve strategic sourcing, the organization is beginning to categorize installation-support spend and assign accountable portfolio managers to respective spend categories. A critical task in this new strategic environment includes the appropriate categorization of Air Force contracts into newly created, manageable spend categories. It has been recognized that current composite categories have the opportunity to be further distinguished into sub-categories leveraging text analytics on the contract descriptions. Furthermore, upon establishing newly constructed categories, future contracts must be classified into these …
The Application Of Text Mining And Data Visualization Techniques To Textual Corpus Exploration, Jeffrey R. Smith Jr.
The Application Of Text Mining And Data Visualization Techniques To Textual Corpus Exploration, Jeffrey R. Smith Jr.
Theses and Dissertations
Unstructured data in the digital universe is growing rapidly and shows no evidence of slowing anytime soon. With the acceleration of growth in digital data being generated and stored on the World Wide Web, the prospect of information overload is much more prevalent now than it has been in the past. As a preemptive analytic measure, organizations across many industries have begun implementing text mining techniques to analyze such large sources of unstructured data. Utilizing various text mining techniques such as n -gram analysis, document and term frequency analysis, correlation analysis, and topic modeling methodologies, this research seeks to develop …
Outlier Classification Criterion For Multivariate Cyber Anomaly Detection, Alexander M. Trigo
Outlier Classification Criterion For Multivariate Cyber Anomaly Detection, Alexander M. Trigo
Theses and Dissertations
Every day, intrusion detection systems catalogue millions of unsupervised data entries. This represents a “big data” problem for research sponsors within the Department of Defense. In a first response to this issue, raw data capture was transformed into usable vectors and an array of multivariate techniques implemented to detect potential outliers. This research expands and refines these techniques by implementing a Chi-Square Q-Q plot-based classification criteria for outlier detection. This methodology has been implemented into an R-based programming solution that allows for a refined and semi-automated user experience for intelligence analysts. Moreover, two case analyses are performed that illustrate how …
Analysis Of A Voting Method For Ranking Network Centrality Measures On A Node-Aligned Multiplex Network, Kyle S. Wilkinson
Analysis Of A Voting Method For Ranking Network Centrality Measures On A Node-Aligned Multiplex Network, Kyle S. Wilkinson
Theses and Dissertations
Identifying relevant actors using information gleaned from multiple networks is a key goal within the context of human aspects of military operations. The application of a voting theory methodology for determining nodes of critical importance—in ranked order of importance—for a node-aligned multiplex network is demonstrated. Both statistical and qualitative analyses on the differences of ranking outcomes under this methodology is provided. As a corollary, a multilayer network reduction algorithm is investigated within the context of the proposed ranking methodology. The application of the methodology detailed in this thesis will allow meaningful rankings of relevant actors to be produced on a …
Design And Test Of A Uav Swarm Architecture Over A Mesh Ad-Hoc Network, Timothy J. Allen
Design And Test Of A Uav Swarm Architecture Over A Mesh Ad-Hoc Network, Timothy J. Allen
Theses and Dissertations
The purpose of this research was to develop a testable swarm architecture such that the swarm of UAVs collaborate as a team rather than acting as several independent vehicles. Commercial-off-the-shelf (COTS) components were used as they were low-cost, readily available, and previously proven to work with at least two networked UAVs. Initial testing was performed via software-in-the-loop (SITL) demonstrating swarming of three simulated multirotor aircraft, then transitioned to real hardware. The architecture was then tested in an outdoor nylon netting enclosure. Command and control (C2) was provided by software implementing an enhanced version of Reynolds’ flocking rules via an onboard …
Analysis Of A Medical Center's Cardiac Risk Screening Protocol Using Propensity Score Matching, Jake E. Johnson
Analysis Of A Medical Center's Cardiac Risk Screening Protocol Using Propensity Score Matching, Jake E. Johnson
Theses and Dissertations
Researchers at the University of Maryland Medical Center in Baltimore have developed a cardiac risk stratification protocol in the hopes of reducing the time-from arrival-to-first-operation for geriatric orthopedic patients. They collected observational data for two years prior to and following the October 2014 implementation of the new screening protocol. Therefore, advanced analytical techniques are required to isolate the treatment effect of the new screening protocol. Propensity score matching (PSM) is used to handle the observational data in order to reduce the bias attributable to the confounding covariates. In addition to PSM, various regression techniques are used to help the researchers …
Variable Speed Simulation For Accelerated Industrial Control System Cyber Training, Luke M. Bradford
Variable Speed Simulation For Accelerated Industrial Control System Cyber Training, Luke M. Bradford
Theses and Dissertations
It is important for industrial control system operators to receive quality training to defend against cyber attacks. Hands-on training exercises with real-world control systems allow operators to learn various defensive techniques and see the real-world impact of changes made to a control system. Cyber attacks and operator actions can have unforeseen effects that take a significant amount of time to manifest and potentially cause physical harm to the system, making high-fidelity training exercises time-consuming and costly. This thesis presents a method for accelerating training exercises by simulating and predicting the effects of a cyber event on a partially-simulated control system. …
An Analysis Of Multi-Domain Command And Control And The Development Of Software Solutions Through Devops Toolsets And Practices, Mason R. Bruza
An Analysis Of Multi-Domain Command And Control And The Development Of Software Solutions Through Devops Toolsets And Practices, Mason R. Bruza
Theses and Dissertations
Multi-Domain Command and Control (MDC2) is the exercise of command and control over forces in multiple operational domains (namely air, land, sea, space, and cyberspace) in order to produce synergistic effects in the battlespace, and enhancing this capability has become a major focus area for the United States Air Force (USAF). In order to meet demands for MDC2 software, solutions need to be acquired and/or developed in a timely manner, information technology infrastructure needs to be adaptable to new software requirements, and user feedback needs to drive iterative updates to fielded software. In commercial organizations, agile software development methodologies and …