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Performance Of Heterogeneous Multi-Agent Systems With Applications In Combined Arms, Robert J. Wilson
Performance Of Heterogeneous Multi-Agent Systems With Applications In Combined Arms, Robert J. Wilson
Theses and Dissertations
Multi-agent systems show great potential for solving problems in complex and dynamic domains. Such systems comprise multiple individual entities called agents. Agents possessing the same behavior or physical form are called homogeneous while agents which differ in these respects are termed heterogeneous. The overall behavior of the system emerges from the many interactions of its component agents. Most multi-agent systems research to date focuses on systems of homogeneous agents, but recent work suggests that heterogeneous agents may improve system performance in certain tasks. This research examines the impact of heterogeneity on multi-agent system effectiveness and investigates the application of multi-agent …
Intercomparison Of Four Microphysics Schemes In Simulating Persistent Arctic Mixed-Phase Stratocumulus Clouds, Zachary A. Cleveland
Intercomparison Of Four Microphysics Schemes In Simulating Persistent Arctic Mixed-Phase Stratocumulus Clouds, Zachary A. Cleveland
Theses and Dissertations
Persistent Arctic mixed-phase stratocumulus clouds (AMPS) are important to the surface radiation budget of the Arctic. Their presence produces warming within the boundary layer and at the surface and inaccurately forecasting AMPS can lead to large, erroneous temperature forecasts. A Large Eddy Simulation of a case study of a persistent AMPS cloud was conducted using the Advanced Research Weather Research and Forecasting (WRF-ARW) model. The case examined occurred near Oliktok Point, AK between 26 and 27 April, 2017. The produced cloud pattern and properties of four different microphysics schemes -- P3, Thompson, Morrison, and WSM6 -- are compared to observations. …
Military Personnel Flight Customer Wait Time Reduction Model Using Simulation, Nicholas C. Anderson
Military Personnel Flight Customer Wait Time Reduction Model Using Simulation, Nicholas C. Anderson
Theses and Dissertations
Customers at Military Personnel Flights (MPFs) have been experiencing long wait times. These customers are typically employees of the United States Air Force and every moment spent waiting for service is a moment they are away from their actual jobs. By reducing the mean wait time of MPF customers, manhours can be saved and customer complaints may be alleviated. This research uses data collected from an MPF to build a discrete-event simulation model of an MPF. A full factorial experimental design was conducted in the model using five factors. The factors included the total number of employees, the total number …
Inverse Optimization: Inferring Unknown Instance Parameters From Observed Decisions, Keith Batista
Inverse Optimization: Inferring Unknown Instance Parameters From Observed Decisions, Keith Batista
Theses and Dissertations
The objective of this research is to develop procedures that estimate selected, unknown parameters over an adversary's investment portfolio across a set of new or existing technologies. To solve for the selected unknown parameters, it is assumed that the adversary is maximizing the portfolio optimization problem and investing along the efficient frontier. The first technique is when an unknown risk attitude exists but all other parameters were known (i.e. expected return, variance, covariance). An adaptive line search technique that iteratively solved the portfolio optimization problem until the adversary's risk parameter was found. The second problem that was solved was when …
Training Logic And Random Forest Models To Predict It Spending, Jacob P. Batt
Training Logic And Random Forest Models To Predict It Spending, Jacob P. Batt
Theses and Dissertations
The Air Force must modernize, but the distribution of funds for technology remains as tight as ever. To this end, the Air Force Audit Agency is looking to utilize machine learning techniques to enhance their capabilities. This research explores Logistic Regression and Random Forest modeling to streamline data collection and cost classification. The final Logistic Regression model identified 4 significant attributes out of the 36 given and was 85 accurate in predicting whether a purchase amount was over or under $10,000. To expand beyond binary classification, a six-category classification Random Forest model was developed. It identified 6 significant attributes and …
Constructing Prediction Intervals With Neural Networks: An Empirical Evaluation Of Bootstrapping And Conformal Inference Methods, Alexander N. Contarino
Constructing Prediction Intervals With Neural Networks: An Empirical Evaluation Of Bootstrapping And Conformal Inference Methods, Alexander N. Contarino
Theses and Dissertations
Artificial neural networks (ANNs) are popular tools for accomplishing many machine learning tasks, including predicting continuous outcomes. However, the general lack of confidence measures provided with ANN predictions limit their applicability, especially in military settings where accuracy is paramount. Supplementing point predictions with prediction intervals (PIs) is common for other learning algorithms, but the complex structure and training of ANNs renders constructing PIs difficult. This work provides the network design choices and inferential methods for creating better performing PIs with ANNs to enable their adaptation for military use. A two-step experiment is executed across 11 datasets, including an imaged-based dataset. …
Evaluating Secure Enclave Firmware Development For Contemporary Risc-V Workstations, Samuel D. Chadwick
Evaluating Secure Enclave Firmware Development For Contemporary Risc-V Workstations, Samuel D. Chadwick
Theses and Dissertations
The emergence of the open-source RISC-V ISA empowers developers and engineers, device manufactures, industry leaders, nation-states, adversaries and allies alike with the unique opportunity to re-evaluate existing Trusted Computing paradigms. Emerging open-source security mechanisms facilitate the proliferation of Confidential Computing principles. These technology standards aim to provide secure enclave computing as a fundamental computing attribute, inherent within the RISC-V ISA specification. Security enforcement within these enclaves are handled by performing computation in memory-isolated, hardware-based, software-defined TEEs. This research evaluates the firmware development procedures required to implement Keystone Enclave on new unsupported hardware. Expressly, this effort extends Keystone SM firmware components …
Malware Detection Using Electromagnetic Side-Channel Analysis, Matthew A. Bergstedt
Malware Detection Using Electromagnetic Side-Channel Analysis, Matthew A. Bergstedt
Theses and Dissertations
Many physical systems control or monitor important applications without the capacity to monitor for malware using on-device resources. Thus, it becomes valuable to explore malware detection methods for these systems utilizing external or off-device resources. This research investigates the viability of employing EM SCA to determine whether a performed operation is normal or malicious. A Raspberry Pi 3 was set up as a simulated motor controller with code paths for a normal or malicious operation. While the normal path only calculated the motor speed before updating the motor, the malicious path added a line of code to modify the calculated …
Evaluating Semantic Matching Techniques For Technical Documents, Rain F. Dartt
Evaluating Semantic Matching Techniques For Technical Documents, Rain F. Dartt
Theses and Dissertations
Machine learning models that employ NLP techniques have become more widely accessible, making them an attractive solution for text and document classification tasks traditionally accomplished by humans. Two such use cases are matching the specialized experience required for a job to statements in applicant resumes, and finding and labelling clauses in legal contracts The AFMC has an immediate need for solutions to civilian hiring. However, there is currently no truth data to validate against. A similar task is contract understanding for which there is the CUAD, a recently published repository of 510 contracts manually labelled by legal experts. The presented …
Detection And Identification Of Cellphone Emitted Light Detection And Ranging Light In Security Camera Video Footage, Tristan V. Creek
Detection And Identification Of Cellphone Emitted Light Detection And Ranging Light In Security Camera Video Footage, Tristan V. Creek
Theses and Dissertations
The prevalence of Light Detection and Ranging (LiDAR) sensors in consumer cellphones has ushered in an era of access to technologies previously inaccessible to the average person. Although LiDAR sensors emit light in the infrared spectrum invisible to the naked eye, many security cameras possess the ability to capture infrared light reflected off surfaces to detect LiDAR light in an environment. Once detected and recorded to video footage, current classification methods fail to identify the LiDAR light. Therefore, this research develops a methodology to detect LiDAR light in security camera video footage and identify it as cellphone LiDAR. A proposed …
Securing Infiniband Networks With End-Point Encryption, Noah B. Diamond
Securing Infiniband Networks With End-Point Encryption, Noah B. Diamond
Theses and Dissertations
The NVIDIA-Mellanox Bluefield-2 is a 100 Gbps high-performance network interface which offers hardware offload and acceleration features that can operate directly on network traffic without routine involvement from the ARM CPU. This allows the ARM multi-core CPU to orchestrate the hardware to perform operations on both Ethernet and RDMA traffic at high rates rather than processing all the traffic directly. A testbed called TNAP was created for performance testing and a MiTM verification process called MiTMVMP is used to ensure proper network configuration. The hardware accelerators of the Bluefield-2 support a throughput of nearly 86 Gbps when using IPsec to …
Exploiting The Iot Through Network-Based Covert Channels, Kyle S. Harris
Exploiting The Iot Through Network-Based Covert Channels, Kyle S. Harris
Theses and Dissertations
Information leaks are a top concern to industry and government leaders. The IoT is a technology capable of sensing real-world events. A method for exfiltrating data from these devices is by covert channel. This research designs a novel IoT CTC without the need for inter-packet delays to encode data. Instead, it encodes data within preexisting network information, namely ports or addresses. Additionally, the CTC can be implemented in two different modes: Stealth and Bandwidth. Performance is measured using throughput and detectability. The Stealth methods mimic legitimate traffic captures while the Bandwidth methods forgo this approach for maximum throughput. Detection results …
Uav Payload Identification With Acoustic Emissions And Cell Phone Devices, Hunter G. Doster
Uav Payload Identification With Acoustic Emissions And Cell Phone Devices, Hunter G. Doster
Theses and Dissertations
The growing presence of Unmanned Aerial Vehicle (UAV) brings new threats to the civilian and military front. In response, the Department of Defense (DoD) is developing many drone detection systems. Current systems use Radio Detection and Ranging (RADAR), Light Detection and Ranging (LiDAR), and Radio Frequency (RF). Although useful, these technologies are becoming easier to spoof every year, and some are limited to line of sight. Acoustic emissions are a unique quality all drones emit. Acoustics are difficult to spoof and do not require line of sight for detection. This research expands the research field of study by creating HurtzHunter, …
Testbed Creation To Study Noise Radar Network Weighting Models And Data Fusion With Radio Tomographic Imaging, Ryan M. Jans
Testbed Creation To Study Noise Radar Network Weighting Models And Data Fusion With Radio Tomographic Imaging, Ryan M. Jans
Theses and Dissertations
Significant research has been conducted on RTI weighting models; however, very little comparative research has been conducted for NRN weighting methods. In order to create comparative weighting methods for NRN, it is necessary to create a testbed which allows for RTI and NRN research to be conducted simultaneously and allow for data fusion methods to also be researched. After creating the testbed and analyzing results, the newly proposed weighting method provides an up to 33% performance increase in target localization accuracy when compared to the previous weighting model used for NRN. The attenuation image resolution improvements resulted in a 79% …
Computational Based Investigation Of Lattice Cell Optimization Under Uniaxial Compression Load, Derek G. Spear, Jeremiah S. Lane, Anthony N. Palazotto, Ryan A. Kemnitz
Computational Based Investigation Of Lattice Cell Optimization Under Uniaxial Compression Load, Derek G. Spear, Jeremiah S. Lane, Anthony N. Palazotto, Ryan A. Kemnitz
Faculty Publications
Structural optimization is a methodology used to generate novel structures within a design space by finding a maximum or minimum point within a set of constraints. Topology optimization, as a subset of structural optimization, is often used as a means for light-weighting a structure while maintaining mechanical performance. This article presents the mathematical basis for topology optimization, focused primarily on the Bi-directional Evolutionary Structural Optimization (BESO) and Solid Isotropic Material with Penalization (SIMP) methodologies, then applying the SIMP methodology to a case study of additively manufactured lattice cells. Three lattice designs were used: the Diamond, I-WP, and Primitive cells. These …
Uav Positioning Data Determined Via Aruco Tags For Aircraft Surface Inspection, Caleb B. Schmidt
Uav Positioning Data Determined Via Aruco Tags For Aircraft Surface Inspection, Caleb B. Schmidt
Theses and Dissertations
Aircraft are frequently inspected to ensure that military and civilian safety standards are adhered to. These inspections are performed pre- and post-flight and are currently performed by trained maintenance personnel. This work furthers the automation of aircraft surface inspection by using ArUco tags to determine the position of the UAV during aerial inspections. The ArUco tag based position data was then compared to a highly accurate infrared motion capture system to determine the viability of this for accurate positioning of the vehicle. This work includes flight experiments with two different UAVs to perform a system viability comparison.
A Reference Architecture For Augmented Reality Maintenance Support, Daniel A. Cuellar
A Reference Architecture For Augmented Reality Maintenance Support, Daniel A. Cuellar
Theses and Dissertations
The current method of preparing Airman to perform tasks in their designated Air Force Specialty is to provide coursework-based initial skills training and on-the job training (OJT) for that specialty. Full qualification for a single Air Force Specialty is estimated to average seven years with OJT consisting of seventy-five percent of that timeline. OJT primarily consists of mastering the use of the Technical Order (TO), a governing document that provides step-by-step task instruction that must be followed explicitly. Though TOs have transitioned to an electronic format, employment of the information has remained the same. A proven aid in instruction and …
Indicators Of Political Instability In The Presence Of Rapid Urban And Youth Population Growth, Douglas W. Hubbard
Indicators Of Political Instability In The Presence Of Rapid Urban And Youth Population Growth, Douglas W. Hubbard
Theses and Dissertations
Large and rapidly growing cities and other urban agglomerations have the potential to become incubators of political instability. This is especially true of rapidly growing cities which are located in countries that are also experiencing high rates of growth in their youth population. Rapid growth rates put stress on urban infrastructure and other institutions, and these stresses can cause major problems for both city and national governments. Knowing when these cities and countries may be trending toward their tipping points regarding political instability will help governments and international organizations develop and implement effective strategies to mitigate the risk of instability.
Critical Evaluation Of Construction Industry-Related Additive Manufacturing Research: A Scientometric Analysis, Tyler J. Brunjes
Critical Evaluation Of Construction Industry-Related Additive Manufacturing Research: A Scientometric Analysis, Tyler J. Brunjes
Theses and Dissertations
Review of construction-related AM literature is used to identify the advantages, challenges, and current trends of the research. Using a scientometric analysis of 522 bibliographic records, this research systematically analyzed construction related AM research to determine the key research areas and trends. Results showed that starting in 2015, the field has been growing at an exponential rate. Recent AM research focused on materials and reinforcement topics, which matched the most notable challenges of AM, which are material rheology, reinforcement, and lacking construction standards. This study provides an insight into AM research and identifies areas requiring more innovation before its commercial …
Predicting Tf33-Pw-100a Engine Failures Due To Oil Issues Using Survival Analyses, Anna M. Davis
Predicting Tf33-Pw-100a Engine Failures Due To Oil Issues Using Survival Analyses, Anna M. Davis
Theses and Dissertations
In 2007, the Office of the Assistant Secretary of Defense for Sustainment pushed for the need to transition to a Condition Based Maintenance Plus (CBM ) initiative for weapon systems in the U.S. Department of Defense. The CBM initiative can help increase aircraft availability (AA) for the United States Air Force. There are many reasons where AA can be affected but one such issue is engine availability primarily due to oil issues. Within the CBM perspective, this study examines the risk of a jet engine failure due to an oil issue and attempts to predict an engines time until next …
Number Of Authorized Suppliers And Supplier Delivery Performance, Beau D. Messenger
Number Of Authorized Suppliers And Supplier Delivery Performance, Beau D. Messenger
Theses and Dissertations
Every year, federal agencies spend over $500 billion to buy a wide variety of products and services, ranging from cutting-edge military aircraft to common office supplies. Supplier performance and sourcing strategies within the Air Force are distinctively complex due to the wide array of weapon systems and limited number of suppliers available within the marketplace. Academics and industry experts agree that the foundation for strong buyer-supplier relationships is a means to achieving superior performance. However, this dynamic can yield varying results when there are a limited number of suppliers available. One of the problems which emerges from the critical need …
Classification And Keyword Identification Of Covid 19 Misinformation On Social Media: A Framework For Semantic Analysis, Grace Y. Smith
Classification And Keyword Identification Of Covid 19 Misinformation On Social Media: A Framework For Semantic Analysis, Grace Y. Smith
Theses and Dissertations
The growing surge of misinformation among COVID-19 communication can pose great hindrance to truth, magnify distrust in policy makers and/or degrade authorities’ credibility, and it can even harm public health. Classification of textual context on social media data relating to COVID-19 is an effective tool to combat misinformation on social media platforms. In this research, Twitter data was leveraged to 1) develop classification methods to detect misinformation and identify Tweet sentiment with respect to COVID-19 and 2) develop a human-in-the-loop interactive framework to enable identification of keywords associated with social context, here, being misinformation regarding COVID-19. 1) Six fusion-based classification …
Understanding Logistics Airmen’S Risk Information Seeking And Processing During The Covid-19 Pandemic: The Role Of Organizational Meetings In An Extended Prism Framework, Christopher T. Price
Understanding Logistics Airmen’S Risk Information Seeking And Processing During The Covid-19 Pandemic: The Role Of Organizational Meetings In An Extended Prism Framework, Christopher T. Price
Theses and Dissertations
The purpose of this survey-based research was to understand how organizational workplace meetings surrounding the COVID-19 pandemic impacted logistics Airmen across the United States Air Force and subsequently played a role into their risk seeking behavior on social media. Specifically, this research tested an expanded Planned Information Risk Seeking Model with organizational meetings as an antecedent to determine if current meetings influenced an Airman's perceived behavioral control, attitude toward seeking, subjective norms, knowledge sufficiency an intentions to seek information regarding COVID-19.
Examining The Effects Of Learning Theory Implemented Within An Online And Self-Paced Learning Path, Trenton M. Woods
Examining The Effects Of Learning Theory Implemented Within An Online And Self-Paced Learning Path, Trenton M. Woods
Theses and Dissertations
The United States military must continue to innovate and improve the way we fight and defend against our near-peer adversaries. Emerging technologies such as machine learning, artificial intelligence, and reverse engineering are paving the way for an increasingly complex security environment. A core tenant of winning in this new era of warfare is how we educate and train our military force. Many of the online trainings made available to service members today fall short in the implementation of existing learning theories.
Emergency Logistics Stochastic Network Optimization With Prepositioning And Distribution Center Support, Christian Graves
Emergency Logistics Stochastic Network Optimization With Prepositioning And Distribution Center Support, Christian Graves
Theses and Dissertations
This study examines the Air Force Medical Service War Reserve Materiel supply chain management through the use of the supply chain optimization software anyLogistix. The goal is to illuminate potential improvements to policies that effect inventory management and test the effects of specific inputs, such as an influx of network support and capacity expansion, into the models. Network optimization shows the cost benefit analysis of these factors and if demand is satisfied through all demand points. Through three unique wartime scenarios, this study looks at the supply chain management of five prehospital analgesic medications: ketamine, morphine, fentanyl intravenous, fentanyl oral …
Analysis Of Task Performance During Radiological Surveillance By Means Of Discrete Event Simulation, Michael H. Ames
Analysis Of Task Performance During Radiological Surveillance By Means Of Discrete Event Simulation, Michael H. Ames
Theses and Dissertations
The surveillance and detection of radioactive contamination on surfaces and in the environment are commonly investigated by surveyors utilizing portable detection equipment. The availability of Discrete Event Simulation (DES) and Human Performance Modeling (HPM) allows for the analysis of physical and cognitive processes associated with these operations, as well as the effect that external environmental factors have on surveyor performance. This research uses the Improved Performance Research Integration Tool (IMPRINT) to approximate the performance of a radiological detection task informed by the observation of six surveyors. The effects of chemical Individual Protective Equipment (IPE) use is evaluated along with the …
Covariance Analysis For Multi-Source Navigation Architecture, Tristan T. Williams
Covariance Analysis For Multi-Source Navigation Architecture, Tristan T. Williams
Theses and Dissertations
Currently, analysis on navigation systems can be slow and computationally expensive using Monte Carlo approaches. Covariance analysis is a tool that can return trade space analysis results promptly and can be computationally reasonable. This research aims to create a covariance analysis tool in a new navigation framework architecture, PntOS. The creation of this covariance tool is explained in coordination with the tool being used in a few different navigation scenarios with the results. These scenarios include a Doppler LiDAR velocity sensor and magnetic anomaly navigation.
A Decision Analysis Framework To Consider Space Congestion In Orbit Selection, Anthony J. Correale
A Decision Analysis Framework To Consider Space Congestion In Orbit Selection, Anthony J. Correale
Theses and Dissertations
Low Earth Orbit (LEO) is becoming more congested, which increases the risk to space missions. Decision makers will need to consider this increase in congestion as an increased risk within their mission engineering process. This thesis proposes a methodology to create and implement a value structure that quantitatively scores a range of orbits based on congestion factors of each orbit and how well each orbit meets mission requirements. This thesis demonstrates this methodology on a set of circular LEO orbits defined by altitude and inclination, and scores this illustrative scenario based on notional mission measures and expected number of encounters …
Formal Spark Verification Of Various Resampling Methods In Particle Filters, Osiris J. Terry
Formal Spark Verification Of Various Resampling Methods In Particle Filters, Osiris J. Terry
Theses and Dissertations
The software verification in this thesis concentrates on verifying a particle filter for use in tracking and estimation, a key application area for the Air Force. The development and verification process described in this thesis is a demonstration of the power, limitation, and compromises involved in applying automated software verification tools to critical embedded software applications.
Generalized Robust Feature Selection, Bradford L. Lott
Generalized Robust Feature Selection, Bradford L. Lott
Theses and Dissertations
Feature selection may be summarized as identifying salient features to a given response. Understanding which features affect the response enables, in the future, only collecting consequential data; hence, the feature selection algorithm may lead to saving effort spent collecting data, storage resources, as well as computational resources for making predictions. We propose a generalized approach to select the salient features of data sets. Our approach may also be applied to unsupervised datasets to understand which data streams provide unique information. We contend our approach identifies salient features robust to the sub-sequent predictive model applied. The proposed algorithm considers all provided …