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Design Of Class F-Based Doherty Power Amplifier For S-Band Applications, Kyle Chang

Master's Theses

Modern RF and millimeter-wave communication links call for high-efficiency front end systems with high output power and high linearity to meet minimum transmission requirements. Advanced modulation techniques, such as orthogonal frequency-division multiplexing (OFDM) require a large power amplifier (PA) dynamic range due to the high peak-to-average power ratio (PAPR). This thesis provides the analysis, design, and experimental verification of a high-efficiency, high-linearity S-band Doherty power amplifier (DPA) based on the Class F PA. Traditional Class F PAs use harmonically tuned output matching networks to obtain up to 88.4% power-added efficiency (PAE) theoretically, however the amplifier experiences poor linearity performance due …

Development Of A Low-Cost Acoustic Gauge For Simultaneous Tide And Wave Measurement, Alexander Kalman Dunn

Master's Theses

High-quality tide and wave data are essential in a variety of fields including coastal engineering, climate science, disaster response, and recreational activities. Accurate data are publicly accessible from government organizations such as the National Oceanic and Atmospheric Administration (NOAA), however the high costs associated with deploying and maintaining their high accuracy gauges results in a deficit of localized data. Commercial gauges available starting at $2,000 are still expensive for local agencies and individual users to deploy and maintain. These commercial options can also be limited in their scope, accuracy, or ease of use. In this thesis, a low-cost acoustic gauge …

Constraint-Driven Open-World Scene Generation, Hunter Borlik

Master's Theses

We introduce an alternative method for open-world scene generation. In this thesis, Graph-based Wave Function Collapse (GWFC) is integrated with Space Colonization Algorithm (SCA) and used to place objects in an unstructured 3D environment. This combined algorithm, Space Colonization Graph-based Wave Function Collapse (SC-GWFC), leverages the constraint-based capabilities of GWFC and the ability of SCA to populate arbitrary 3D volumes. We demonstrate that objects of variable scale can be successfully used with SC-GWFC. Since this algorithm is run in an interactive environment, we demonstrate iterative modifications to a partially complete scene and incorporate PCG into a scene editing process. As …

Gyroless Nanosatellite Attitude Determination Using An Array Of Spatially Distributed Accelerometers, Kory J. Haydon

Master's Theses

The low size and budget of typical nanosatellite missions limit the available sensors for attitude estimation. Relatively high noise MEMS gyroscopes often must be employed when accurate knowledge of the spacecraft’s angular velocity is necessary for attitude determination and control. This thesis derived and tested in simulation the “Virtual Gyroscope” algorithm, which replaced a standard gyroscope with an array of spatially distributed accelerometers for a 1U CubeSat mission. A MEMS accelerometer model was developed and validated using Root Allan Variance, and the Virtual Gyroscope was tested both in the open loop configuration and as a replacement for a gyroscope in …

Mobile Firewall System For Distributed Denial Of Service Defense In Internet Of Things Networks, Lorenzo B. Gardea

Master's Theses

Internet of Things (IoT) has seen unprecedented growth in the consumer space over the past ten years. The majority of IoT device manufacturers do not, however, build their products with cybersecurity in mind. The goal of the mobile firewall system is to move mitigation of network-diffused attacks closer to their source. Attack detection and mitigation is enforced using a machine that physically traverses the area. This machine uses a suite of security tools to protect the network. Our system provides advantages over current network attack mitigation techniques. Mobile firewalls can be deployed when there is no access to the network …

Predicting Location And Training Effectiveness (Plate), Erik Rolf Bruenner

Master's Theses

Abstract Predicting Location and Training Effectiveness (PLATE)
Erik Bruenner

Physical activity and exercise have been shown to have an enormous impact on many areas of human health and can reduce the risk of many chronic diseases. In order to better understand how exercise may affect the body, current kinesiology studies are designed to track human movements over large intervals of time. Procedures used in these studies provide a way for researchers to quantify an individual’s activity level over time, along with tracking various types of activities that individuals may engage in. Movement data of research subjects is often collected through …

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Autonomous Attitude Consensus For Nanosatellite Formations In Leo, Laird J. Mendelson

Master's Theses

Consensus strategies are examined as a possible approach to achieving attitude alignment for a large, close-proximity formation of nanosatellites in low earth orbit (LEO). An attitude-only distributed consensus approach is selected for further consideration due to its comparatively low data transmission requirements. The convergence of a connected network of satellites to the attitude agreement subspace under this control law is shown using a Lyapunov stability approach with a set of idealizing assumptions. A moderate-fidelity simulation demonstrates the performance of the control law under realistic conditions that violate those assumptions. Particular emphasis is placed on the conditions that arise from the …

Neural Tabula Rasa: Foundations For Realistic Memories And Learning, Patrick R. Perrine

Master's Theses

Understanding how neural systems perform memorization and inductive learning tasks are of key interest in the field of computational neuroscience. Similarly, inductive learning tasks are the focus within the field of machine learning, which has seen rapid growth and innovation utilizing feedforward neural networks. However, there have also been concerns regarding the precipitous nature of such efforts, specifically in the area of deep learning. As a result, we revisit the foundation of the artificial neural network to better incorporate current knowledge of the brain from computational neuroscience. More specifically, a random graph was chosen to model a neural system. This …

Wasm-Pbchunk: Incrementally Developing A Racket-To-Wasm Compiler Using Partial Bytecode Compilation, Adam C. Perlin

Master's Theses

Racket is a modern, general-purpose programming language with a language-oriented focus. To date, Racket has found notable uses in research and education, among other applications. To expand the reach of the language, there has been a desire to develop an efficient platform for running Racket in a web-based environment. WebAssembly (Wasm) is a binary executable format for a stack-based virtual machine designed to provide a fast, efficient, and secure execution environment for code on the web. Wasm is primarily intended to be a compiler target for higher-level languages. Providing Wasm support for the Racket project may be a promising way …

Neural Compression Inference Accelerator: A Cost And Energy-Effective Alternative To Conventional Machine Learning Inference Methods, Matthew Wallace

Master's Theses

Recent developments in machine learning and artificial intelligence have sparked an influx of workloads that require specialized computer hardware for cloud services. The hardware running machine learning models predominantly consists of graphics processing units (GPUs) and tensor processing units (TPUs). However, these com- ponents are expensive for cloud services to purchase, costly for customers to rent, prone to price spikes, and energy-intensive. In this research we show that both cloud services and customers would benefit from utilizing field programmable gate arrays (FPGAs) to alleviate the aforementioned challenges. An FPGA can be configured as a machine learning accelerator, operating similarly to …

A Novel Approach To Extending Music Using Latent Diffusion, Keon Roohparvar, Franz J. Kurfess

Master's Theses

Using deep learning to synthetically generate music is a research domain that has gained more attention from the public in the past few years. A subproblem of music generation is music extension, or the task of taking existing music and extending it. This work proposes the Continuer Pipeline, a novel technique that uses deep learning to take music and extend it in 5 second increments. It does this by treating the musical generation process as an image generation problem; we utilize latent diffusion models (LDMs) to generate spectrograms, which are image representations of music. The Continuer Pipeline is able to …

Experimental Characterization And Computer Vision-Assisted Detection Of Pitting Corrosion On Stainless Steel Structural Members, Riley J. Muehler

Master's Theses

Pitting corrosion is a prevalent form of corrosive damage that can weaken, damage, and initiate failure in corrosion-resistant metallic materials. For instance, 304 stainless steel is commonly utilized in various structures (e.g., miter gates, heat exchangers, and storage tanks), but is prone to failure through pitting corrosion and stress corrosion cracking under mechanical loading, regardless of its high corrosion resistance. In this study, to better understand the pitting corrosion damage development, controlled corrosion experiments were conducted to generate pits on 304 stainless steel specimens with and without mechanical loading. The pit development over time was characterized using a high-resolution laser …

Investigation Of Placement Of Polyethylenimine Within Thin Film Composite Reverse Osmosis Membranes For Enhanced Anti-Fouling Properties, Taylor F. Austin

Master's Theses

Fresh water scarcity is an alarming issue for communities across the globe. The development of water recycling and reuse technologies has become crucial in expanding the limited water resources. Reverse osmosis (RO) is among the key processes that can treat wastewater to meet potable water reuse standards. Despite the advancements in RO membrane technologies, many challenges persist regarding the operation and maintenance of RO membranes, such as membrane fouling. Extensive research investigations have focused on developing RO membrane modifications to combat the decreased performance due to fouling. Polyethylenimine (PEI) is a promising polymer used for enhancing the anti-fouling properties of …

A Minor Place: A Short Story Collection, Nathaniel Pyle

Master's Theses

In this collection, characters often face interior struggles such as past lives, abusive upbringings, dead partners, and relationship struggles. A Minor Place concerns loneliness and existentialism set with a melancholy, southern gothic setting. Characters toil with their psychological state within a shared and collective universe of the unknown. The characters found within A Minor Place deal with sensitive issues such as loss, isolation, and overcoming their difficulties. A Minor Place implements narratives to showcase a "minor” tonality and coloration and style to accompany this titular minor place.

Estimation Of Quantitative Genetic Parameters Of The Eastern Oyster (Crassostrea Virginica) In The Gulf Of Mexico, Heather King

Master's Theses

The decline of natural oyster reefs in Gulf of Mexico (Gulf) states has stimulated the development of aquaculture to support the industry and restoration programs. Gulf habitats feature diverse salinity environments that may require oysters bred for habitat-specific optimal genetic characteristics. In this work, genetic parameters for performance in habitats with different salinity were estimated. In September 2020, 102 males and 102 females sourced from 17 natural reefs across the northern Gulf were bred according to 2 males x 2 females non-overlapping factorial crossing designs, resulting in 204 full and half sibs. All families were pooled after fertilization according to …

Class F Power Amplifier And Doherty Power Amplifier Design, Shreyansh Suman

Master's Theses

The main goal of this thesis is to design and fabricate a power amplifier suitable for entry in IMS 2023 High Efficiency Power Amplifier Student Design Competition. Power amplifier design requires multiple design tradeoffs, for example, efficiency and linearity are the two main conflicting design parameters that require careful tradeoff to ensure optimum performance. Two prototypes are designed and fabricated for the competition: Class F operating at 1.5 GHz and Doherty Power Amplifier designed for an operating frequency of 3 GHz. Both prototypes meet the minimum requirement for qualifying in the IMS 2023 HEPA SDC. Class F power amplifier designed …

Distributed Control Of Servicing Satellite Fleet Using Horizon Simulation Framework, Scott Plantenga

Master's Theses

On-orbit satellite servicing is critical to maximizing space utilization and sustainability and is of growing interest for commercial, civil, and defense applications. Reliance on astronauts or anchored robotic arms for the servicing of next-generation large, complex space structures operating beyond Low Earth Orbit is impractical. Substantial literature has investigated the mission design and analysis of robotic servicing missions that utilize a single servicing satellite to approach and service a single target satellite. This motivates the present research to investigate a fleet of servicing satellites performing several operations for a large, central space structure.

This research leverages a distributed control approach, …

Hydric Physiology Of Lizards, Savannah Weaver

Master's Theses

Chapter 1: Animals can respond to extreme climate by behaviorally avoiding it, or by physiologically coping with it. We understand behavioral thermoregulation and physiological thermal tolerances, but water balance has largely been neglected. Climate change includes both global warming and changes in precipitation regimes, so improving our understanding of organismal water balance is increasingly urgent. We assessed the hydric physiology of endangered Blunt-nosed Leopard Lizards (Gambelia sila) by measuring cutaneous evaporative water loss (CEWL), plasma osmolality, body mass, and body condition throughout their active season. On average, G. sila had low CEWL that is likely desert-adaptive, and high …

Play Area Utilization Optimization For Room-Scale Exploration Of Virtual Worlds, Chase Vanderzwan

Master's Theses

Virtual Reality (VR) opens up new possibilities for developers to create immersive worlds and experiences. While it’s possible to craft unique and engaging interactive environments with unprecedented realism, the virtual world is constrained by the real one. Current approaches to player navigation in VR applications include joystick controls, teleportation, and motion-based movement. While these methods are effective in certain scenarios to overcome real-world limitations, my research introduces a novel approach that leverages room scale-based movement, with portals, to traverse a given VR world. This work presents algorithms that accurately predict the percentage of play area utilized, and rules to implement …

Balancing Privacy And Accuracy In Iot Using Domain-Specific Features For Time Series Classification, Pranshul Lakhanpal

Master's Theses

ε-Differential Privacy (DP) has been popularly used for anonymizing data to protect sensitive information and for machine learning (ML) tasks. However, there is a trade-off in balancing privacy and achieving ML accuracy since ε-DP reduces the model’s accuracy for classification tasks. Moreover, not many studies have applied DP to time series from sensors and Internet-of-Things (IoT) devices. In this work, we try to achieve the accuracy of ML models trained with ε-DP data to be as close to the ML models trained with non-anonymized data for two different physiological time series. We propose to transform time series into domain-specific 2D …

Implementation Of Topology Optimization Into The Mechanical Design Process, Nolan Clapp

Master's Theses

Topology Optimization is a lightweighting method based on finite element analysis that produces a part with optimum material distribution in the design space. Results from topology optimization often have organic shapes and curves that are difficult if not impossible to machine with traditional subtractive manufacturing methods. This paper analyzes the implementation of the Solidworks® Topology Optimization add-in into the mechanical design process and discusses required postprocessing to ensure manufacturability of the optimized part though a case study on two example parts. Results of traditional optimization, topology optimization and “selective” optimization (optimization using the results from topology optimization to selectively remove …

Effects Of Intertidal Position On The Response To Oxygen And Desiccation Stress In The Common Acorn Barnacle, Balanus Glandula, Megan M. Dotterweich

Master's Theses

Sessile invertebrates in the rocky intertidal experience intermittent periods of air exposure due to tidal flux, presenting risks of temperature extremes, hypoxia, nutrient limitation, and most dangerously, desiccation. Microscale variation in severity and frequency of these risks is widely dependent on vertical position within the intertidal zone. Common acorn barnacles (Balanus glandula) have a wide vertical distribution in the intertidal, creating large differences in microhabitat between the highest and lowest individuals in the population. This study set out to explore whether tidal position dependent differences exist in the response to oxygen and desiccation stress in B. glandula. …

Suppression Of National Identities: Ukrainian And Baltic Cultures In The Soviet Union, Jonathan H. Mastman

Master's Theses

This thesis defines the formation and consummation of Soviet Bolshevism as another imperialist force rather than its stated objective of freeing the people of the United Soviet Socialist Republics from the clutches of an inequitable elite. Through the policies and objectives of the Soviet government the workers and citizens of Ukraine and the Baltic republics were not liberated or given autonomy over their lives and labor, as Marxist-Leninism would have them believe. I review the Russification efforts found first in the Tsarist Russian Empire and then continued by Soviets in the nature of pursuing or denying cultural, political, and economic …

Development Of Wiskott-Aldrich Syndrome Knock Out Protocol For Drug Substance Assay Development, Julia C. Hanna

Master's Theses

Wiskott-Aldrich Syndrome (WAS) is a rare X-linked primary immunodeficiency affecting approximately 1 in 100,000 live XY births in North America and is caused by a mutation to the WAS gene which is expressed across hematopoietic lineages. The WAS protein (WASp) plays a role in regulating actin polymerization. On a cellular level, there are a variety of effects of a lack of WASp or expression of a dysfunctional WASp protein for patients including issues with migration, adhesion, chemotactic response, phagocytosis, activation, and proliferation across different cell types in addition to reduced platelet size and output. This can lead to several systematic …

Deep Learning Recommendations For The Acl2 Interactive Theorem Prover, Robert K. Thompson, Robert K. Thompson

Master's Theses

Due to the difficulty of obtaining formal proofs, there is increasing interest in partially or completely automating proof search in interactive theorem provers. Despite being a theorem prover with an active community and plentiful corpus of 170,000+ theorems, no deep learning system currently exists to help automate theorem proving in ACL2. We have developed a machine learning system that generates recommendations to automatically complete proofs. We show that our system benefits from the copy mechanism introduced in the context of program repair. We make our system directly accessible from within ACL2 and use this interface to evaluate our system in …

Contextually Dynamic Quest Generation Using In-Session Player Information In Mmorpg, Shangwei Lin

Master's Theses

Massively multiplayer online role-playing games (MMORPGs) are one of the most

popular genres in video games that combine massively multiplayer online genres with

role-playing gameplay. MMORPGs’ featured social interaction and forms of level pro-

gression through quest completion are the core for gaining players’ attention. Varied

and challenging quests play an essential part in retaining that attention. However,

well-crafted content takes much longer to develop with human efforts than it does to

consume, and the dominant procedural content generation models for quests suffer

from the drawback of being incompatible with dynamic world changes and the feeling

of repetition over time. …

Estimating The Impact Of Infill Housing On Reduction In Vehicle Miles Traveled, Peyton Marie Ratto

Master's Theses

Vehicle miles traveled (VMT) and its relationship with the built environment has been extensively studied. Most notably, five D variables of the built environment including density, diversity, design, destination accessibility, and distance to transit are the key variables included in this research to explain VMT generation from housing developments. This thesis uses prior research that developed robust statistical models and findings to create a framework to estimate VMT reduction affected by infill housing developed using incentives provided by the state compared to a regional comparator. The regional comparator is typically a suburban single-family housing development in the region. The models …

Examining The Use Of A Network Bypass To Circumvent Data Diodes Within Industrial Control Systems, Bryce Molesh

Master's Theses

Our modern world relies upon large scale industrial plants, that are manged by Industrial Control Systems (ICS), to provide critical services such as electricity, water, or waste processing. Over time, these systems have been increasingly connecting outdated systems to modern internet technology to provide additional functionality such as real-time monitoring while also enabling operators to conduct modern business analytics. Thus, these plants offer a potential target for attackers. Recently, such attacks on Industrial Control Systems have increased in number with well publicized attacks such as Stuxnet and TRISIS. To protect against such attacks while also modernizing their networks, Industrial Control …

An Empirical Evaluation Of Neural Process Meta-Learners For Financial Forecasting, Kevin G. Patel

Master's Theses

Challenges of financial forecasting, such as a dearth of independent samples and non- stationary underlying process, limit the relevance of conventional machine learning towards financial forecasting. Meta-learning approaches alleviate some of these is- sues by allowing the model to generalize across unrelated or loosely related tasks with few observations per task. The neural process family achieves this by con- ditioning forecasts based on a supplied context set at test time. Despite promise, meta-learning approaches remain underutilized in finance. To our knowledge, ours is the first application of neural processes to realized volatility (RV) forecasting and financial forecasting in general.

We …

Coupled Boundary Conditions For Modeling Airbreathing Engines, Adam Louis Waldemarson

Master's Theses

Modeling the flight conditions of an aircraft that utilizes an airbreathing propulsion system necessitates a method to account for the increase in energy introduced into the flow. Current methods for modeling engines either assign fixed conditions on flat faces on the intake and exhaust through a manual process with the use of external models or attempt to model the flow through the engine within the simulation using complex and computationally expensive geometry and solvers. The method presented attempts to provide an intermediate option to model airbreathing engines through coupling the intake and exhaust boundary conditions with a parametric engine model. …