Digital Commons Network^™

A Novel Reinforcement Learning Method For Efficient Cross-Training Between Real And Simulated Robots, Zhonglin Liang

Master's Theses

Training reinforcement learning policy in a simulated environment can be a go-to choice for many research topics, as a simulated environment provides flexibility and costs less than building a physical environment for training. However, policy trained in a simulated environment often fails to transfer to the real environment for problems that have a more complex dynamics. As the solution, Sim2Real was proposed and it categorizes techniques that improve the performance of the transfer from simulation to reality. Sim2Real is an area of study that focuses on utilizing simulation data to train models that can apply to real world environment. It …

An Assessment Of Anthropogenic Injuries On White Sharks (Carcharodon Carcharias) In Central California, Kaitlyn Yee

Master's Theses

As human activities increasingly impact marine ecosystems, understanding the effects of anthropogenic activity on white sharks is important for their continued conservation. Human-induced injuries are observed in many shark species. Such injuries have been found to have physiological and ecological impacts. Four sites in Central California off the coasts of Aptos, Año Nuevo Island, Southeast Farallon Island, and Point Reyes are all known areas of white shark aggregation with varying levels of human use and protection. Utilizing a vast video database, this study evaluated the effects of natural and non-natural anthropogenic shark injury types across all locations, age classes, and …

The Impact Of Adverse Childhood Experiences On Later Desistance Among Serious Juvenile Offenders From A Broken Family Composition, Olivia Franklin

Master's Theses

The current study aimed to contribute to the overall knowledge of desistance patterns among juveniles by exploring them among serious juvenile offenders who come from a broken home. Utilizing the Pathways to Desistance (PTD) dataset, this study used logistic regression to examine the impact of family composition on later desistance while controlling for various adverse childhood experiences (ACEs) one might experience. Two research questions guide this study: (1) Does family composition (i.e., “broken homes”) impact later desistance among serious adolescent offenders, while controlling for important criminological predictors (i.e., self-control and antisocial peer influence)? (2) Is the quality of one’s home …

Hardware Control Unit For Trusted Program Verification System, Jake Owen Alt

Master's Theses

Trust in the underlying hardware is the foundational step towards trusting the correctness and integrity of a software application. However, verifying that today's extremely complex processors work exactly as intended has not been feasible, as evidenced by several recent hardware bugs. Trustworthy, formally verified processors currently forego intricate performance enhancements such as out-of-order execution, hampering them substantially versus their less secure counterparts.

The Containment Architecture with Verified Output (CAVO) system solves this problem by isolating the host system and requiring the result of each instruction to be validated by a small, trusted hardware module called the Sentry. Any transmissions to …

Understanding Teachers’ Responses To Parental Demands In The Midst Of Competing Responsibilities, Kathryn Battafarano

Master's Theses

This study builds upon a plethora of educational research and focuses specifically on middle school grade level teachers. I predominantly utilized qualitative interviews to understand how teachers respond to parental demands; these answers were supplemented by some quantitative data about their schools. The study configures information about teachers’ school environments and requirements, teachers’ interactions with parents, and how teachers deal with parental demands in relation to other demands and requirements. Effort was made to investigate how teacher experience, teaching style, and subject matter as well as school type (e.g., socio-economic makeup of the school) and school location influence parental demands …

Queer Futurity Needs Queer Grief: An Analysis Of The U.S. Public Response To Queer Loss, Jordan Nicole Mckinnon

Master's Theses

Grief is an inevitable part of the human experience. However, communities, especially those where a majority of members have disprivileged identities, experience disenfranchised grief, or grief that is not openly acknowledged, socially accepted, or publicly mourned. Members of the LGBTQIA+ (lesbian, gay, bisexual, transgender, queer, intersex, asexual, plus other identities not encompassed in the acronym) community, and their allies can experience a type of disenfranchised grief known as queer grief. I argue that everyone, not just allies and members of the LGBTQIA+ community, should recognize and publicly acknowledge queer grief, because if queer lives lost are not recognized as worthy …

Impacts Of Stormwater And Land Cover On The Abundance, Transport, And Composition Of Anthropogenic Litter In Urban Watersheds, Bailey Austin Schwenk

Master's Theses

Anthropogenic litter (AL; trash) is defined as any manufactured item that ends up in the environment. AL consists of many different materials including glass, metal, and plastic, the latter of which typically represents a dominant constituent and has been a major focus of research. Plastic litter and other AL types are pervasive to all types of ecosystems, are persistent in the environment, and are increasing. Rivers are a major conduit transporting AL to oceans. However, rivers also retain and transform AL. More research is needed to understand AL dynamics within rivers, which will improve global models of AL movement and …

Dynamic Maze Puzzle Navigation Using Deep Reinforcement Learning, Luisa Shu Yi Chiu

Master's Theses

The implementation of deep reinforcement learning in mobile robotics offers a great solution for the development of autonomous mobile robots to efficiently complete tasks and transport objects. Reinforcement learning continues to show impressive potential in robotics applications through self-learning and biological plausibility. Despite its advancements, challenges remain in applying these machine learning techniques in dynamic environments. This thesis explores the performance of Deep Q-Networks (DQN), using images as an input, for mobile robot navigation in dynamic maze puzzles and aims to contribute to advancements in deep reinforcement learning applications for simulated and real-life robotic systems. This project is a step …

History & Evolution Of Plastic Mulching Technology: An Ethnography Of California Strawberry Plasticulture, Kalea Conrad

Master's Theses

This ethnography draws on key informant interviews and participant observation to produce a case study about plastic mulching as an important industry standard in specialty crop production. It documents the historic adoption and present role of plastic mulching technology in California strawberry production and addresses the characteristics of commercial standard management that inhibit the adoption of alternative mulching practices. It complements extensive research on strawberry pathology and fumigation, breeding innovations, fertilizer and pesticide treatments, and maximization of yields to incorporate participants’ lived experiences and knowledge of mulch origins, the technology adoption process, mulch benefits and drawbacks, the state of agricultural …

Design And Implementation Of An Inverted Short Baseline Acoustic Positioning System, Jakob Frabosilio

Master's Theses

This document details the design, implementation, testing, and analysis of an inverted short baseline acoustic positioning system. The system presented here is an above-water, air-based prototype for an underwater acoustic positioning system; it is designed to determine the position of remotely-operated underwater vehicles (ROVs) and autonomous underwater vehicles (AUVs) in the global frame using a method that does not drift over time.

A ground-truth positioning system is constructed using a stacked hexapod platform actuator, which mimics the motion of an AUV and provides the true position of an ultrasonic microphone array. An ultrasonic transmitter sends a pulse of sound towards …

A Data-Driven Framework For Analyzing And Predicting Social Media Engagement During Rumor Propagation, Joseph E. Faza

Master's Theses

The spread of rumors on social media has become a significant concern, as platforms like X (formerly known as Twitter) enable rapid dissemination of unverified information. These rumors can shape public perception and behavior, making it crucial to understand the dynamics of their spread. The main objective of this study is to explore how users interact with rumor-related tweets and identify key factors that predict tweet engagement. By analyzing tweets from seven different rumor events, this research aims to uncover patterns in user engagement and provide insights into the spread of misinformation. The study utilized a dataset of tweets from …

Assessment Of Dune Change Using Historical Aerial And Satellite Photos, Topographic Surveys, And Wave Data At Toro Creek Beach, Owen D. Emerson

Master's Theses

Coastal sand dunes play an important role in the littoral processes of California’s coastline. Functioning as both source and sink for sand, these dunes often protect coastal infrastructure and provide a buffer between anthropogenic development and coastal forces. At Toro Creek Beach, north of Morro Bay California, recent extreme winter storms have raised concerns about the erosion of the sand dunes that front California State Highway 1. This thesis attempts to characterize the historical growth and recession patterns of the Toro Creek dunes since 1977, the dune movement over the 2023-2024 winter seasons, the wave forcings behind recent high erosion …

Enabling Emg-Based Silent Speech Transcription Through Speech-To-Text Transfer Learning, Alexander T. Garcia

Master's Theses

In recent years, advances in deep learning have allowed various forms of electrographic signals, such as electroencephalography (EEG) and electromyography (EMG), to be used as a viable form of input in artificial intelligence applications, particularly for applications in the medical field. One such topic that EMG inputs have been used is in silent speech interfaces, or devices capable of processing speech without an audio-based input. The goal of this thesis is to explore a novel method of training a machine learning model to be used for silent speech interface development: using transfer learning to leverage a pre-trained speech recognition model …

Survey Of Soilborne Pathogens Infecting Strawberry In Oxnard, California & Effect Of Planting Date And Chill Treatment On Yield Of Strawberry, Samantha Z. Simard

Master's Theses

Survey to quantify the frequency of the five main pathogens (Macrophomina phaseolina, Fusarium oxysporum f. sp. fragariae races 1 and 2, Verticillium dahliae, and Phytophthora spp.) infecting strawberry in the Oxnard growing district of California. M. phaseolina was the most prevalent pathogen detected in diseased plants in the Oxnard growing district, present in 67.6% of samples positive for at least one pathogen. F. oxysporum f. sp. fragariae race 1 (35.3%), V. dahlia (8.8%), F. oxysporum f. sp. fragariae race 2 (5.9%) and Phytophthora spp. (2.9%) followed at lower prevalence. Associations were found between fewer drip irrigation lines …

Supervised Classification Modeling On Louisiana Medicaid Data: A Comparative Study, Yead Rahman

Master's Theses

This thesis systematically optimizes and compares state-of-the-art supervised classification models for Louisiana Medicaid data targeting clinical services, COVID-19 infection, and tobacco use. These target variables are critically important as they represent key health outcomes and behaviors among Medicaid enrollees in Louisiana, a population often characterized by poverty and limited access to education. This study applies advanced machine learning techniques to identify the best model for multinomial and binary classification tasks. These include models such as Logistic Regression, XGBoost, AdaBoost, Random Forest, Decision Tree, Artificial Neural Networks, and Naïve Bayes. Extensive tuning of the hyperparameters and optimization of each classifier were …

Adherence To Mediterranean Diet Principles In Minority College Students, Bridgette Lorraine Barbre

Master's Theses

Every year, millions of young adults attend college. The Centers for Disease Control and Prevention (CDC) lists heart disease and diabetes as the top health concerns for minority Americans. African American and Hispanic/Latino communities could see a reduction in illness risk by promoting physical activity and healthy eating habits such as the Mediterranean Diet. Research indicates that young adults may benefit significantly from taking charge of their eating habits at the crucial point in their transition from high school to college. By determining the dietary patterns of minority college students, as related to the Mediterranean diet principles, this study intends …

Robotic Odor Source Localization Using Vision And Olfaction Sensing, Sunzid Hassan

Master's Theses

Robotic Odor Source Localization (ROSL) technology allows autonomous agents like robots to find an odor source in unknown environments. A successful odor source location depends crucially on an effective navigation algorithm that directs the robot towards the odor source. This thesis is a combination of three projects. First, we detail development of a versatile multi-modal robotic platform for ROSL real-world ROSL experimentation and discussed real-world validation of a traditional olfactionbased ROSL algorithm. Secondly, we introduced vision in ROSL by proposing a fusion navigation algorithm that integrates deep-learning enabled vision and olfaction-based navigation. This hybrid approach tackles challenges such as turbulent …

Evolutionary Patterns Of Anolis Lizard Skulls: An Investigation In Geometric Morphometrics And An Educational Exploration Of Structure And Function, Katherine Beyer Starr

Master's Theses

This study explores the evolutionary patterns of Anolis lizard skulls and integrates findings into a curriculum focused on elucidating the structure and function of a lizard's head. The first objective was to develop an understanding of how the evolutionary patterns, of an extraordinary group of lizards (Anolis) compares to their relatives. Most of the prior research on Anolis morphology has focused on the post-cranium because of its significance towards subdivision of the arboreal habitat. But the group’s remarkable diversity in head shape has been seriously under-investigated. By performing geometric morphometric analysis of skull shape across a large sample of anoles …

A Matter Of Life And Death: The Conceptualization And Theological Significance Of Blood In The Pentateuch, Jared Greer

Master's Theses

This 2024 Master of Theological Studies thesis at Lipscomb University analyzes the conceptualization and theological significance of blood within the Pentateuch. While the thesis does attend to various anthropological concerns (i.e., the sociocultural understandings of blood that inform the text), it is more chiefly concerned with how such understandings of blood contribute to the broader theology of the Pentateuch. Using a canonical interpretive approach that respects both the diachronic nature of the text and the theological unity intended by its final redactors, the thesis primarily explores the two principal contexts in which blood appears in the Pentateuch: Israel’s cultus and …

Development Of Targeted, Statin Loaded Nanoparticle Delivery Systems, Stephanie Judkins

Master's Theses

Statins lower endogenous production of cholesterol through their inhibition of the mevalonate pathway. Lipophilic statins in particular exhibit anti-inflammatory effects at supraphysiological doses by preventing downstream signaling through small molecule GTPases. Interest lies in development of statins as anti-inflammatory therapeutics, however, achieving effective doses locally incurs serious off-target effects. Our goal was to develop and optimize a targeted delivery system to traffic these drugs to inflamed sites and unload the drug at effective concentrations while avoiding systemic exposure. Lipophilic statins (lovastatin, simvastatin, and atorvastatin) were incorporated into polymeric nanoparticles (NPs) due to their hydrophobicity. We have shown that statins released …

Investigating The Roles Of Sirtuins During Cvb3 Infection And Innate Immunity, Bridget M. Hulsebosch

Master's Theses

Coxsackievirus B3 (CVB3) is an enterovirus that chronically infects heart tissue, leading to dilated cardiomyopathy. However, no vaccines or antivirals exist for CVB3 infection or to treat CVB3-induced dilated cardiomyopathy, except for a heart transplant. Sirtuins (SIRTs), class III lysine deacetylases, have diverse and complex roles in cellular functions, contributing to energy production, NF-κB signaling, cell cycle regulation, and inflammation. Previous studies showed that SIRTs are essential for hepatitis B and A viral replication and regulate the IFN response during viral infection. However, the role of SIRT1 and 2 during CVB3 infection is entirely unknown. CVB3-infected SIRT1 and SIRT2 knockout …

Sport And Environmental Issues: Ncaa Division I Student-Athletes’ Personal Experiences, Ivanna M. Anderson-Villela

Master's Theses

While sport ecology is a growing category in sport management literature, there is a lack of research exploring athletes’ experiences regarding environmental issues, and the impacts environmental issues have on student-athletes. The present study qualitatively explored the personal lived experiences of eight NCAA Division I student-athletes regarding environmental issues with the aim of identifying potential influences on values and beliefs through social norms and understanding the student-athlete perspective. Thematic analysis identified 152 raw data themes and 19 higher order themes, which were organized into four central themes: awareness, care and concern from athletic departments, implications, and advocacy. Generally, student-athletes perceived …

A Qualitative Evaluation Of Speech Sound Disorder Treatment Apps For Children, Rachel G. Barnett

Master's Theses

This research examined 20 speech sound disorder (SSD) treatment apps’ features and costs as related to the feature matching process within speech-language therapy. Methods included the development of a 67-item SSD checklist and sorted into 9 categories, including linguistic levels, speech models, software customization, cost, game types, image types, technical elements, feedback types, and engagement and manipulation. Two independent reviewers applied the checklist to randomly selected contemporary apps available on both iPhones and iPads. App cost was capped at $25. Results indicated that app cost was not a good predictor of feature quantity and contemporary apps had some relevant feature …

Beyond ‘Manning Up’: The Impact Of Hegemonic Masculinity & Gender Norms On Mental Health Help-Seeking Among College Men, Joslyn Barragan

Master's Theses

This narrative inquiry study was conducted to explore college men's conceptualization of masculinity and gender norms and their relationship with mental health-related help-seeking behaviors. Through semi-structured interviews with seven men, I gathered their perceptions of mental health support and the obstacles they encountered in accessing it. Drawing from Connell's conceptualization of masculinities, this study locates their narratives within the broader framework of societal expectations, highlighting the complexities of men's attitudes and behaviors toward mental health counseling. Ultimately, five critical narratives were discovered: a) Initial models of masculinity emerge through socialization; b) Men encounter barriers to mental health care from all …

Language Dominance And Connected Speech In Multilingual Spanish-English Adults, Alyson Jimenez

Master's Theses

With a growing prevalence of multilingual, Spanish-English speakers in the United States, speech-language pathologists (SLPs) face limited research to learn about how to evaluate the language skills of this population. Exploring evaluation tools, more specifically, connected speech samples, and their effectiveness in assessing the dynamic nature of multilingualism with adults who speak Spanish and English can assist SLPs in making informed recommendations. This study aimed to investigate relations between language dominance and connected speech with cognitive-healthy multilingual Spanish-English adults. Language dominance was further examined by two perspectives that an SLP may utilize in their evaluation: evaluated and perceived. Correlations between …

Online Trolling, Harassment, Misinformation: The Psychological Predictors Of Dark Participation, Randy Kim

Master's Theses

This study aims to examine the reasons why certain individuals engage in “dark participation”, antisocial social participation online involving behavior such as trolling, hate speech, harassment, and spreading disinformation. Online toxicity has increasingly destabilized our ability to engage in socially important discourse online, and trolling has such a strong effect on our environment to the point where the 2016 presidential election was, in part, influenced by online trolls. We theorize that dark participation (DP) will be predicted by high levels of moral disengagement (MD), need for chaos (NFC), and meaninglessness in life (MLN) and self concept clarity (SCC). A series …

Deep-Learning Approaches To Predict Remaining Useful Life Of Hard Disks, Rohan Mohapatra

Master's Theses

On a daily basis, data centers process huge volumes of data using inexpensive hard disks. Data stored in these disks serve a range of critical functional needs from financial, and healthcare to aerospace. As such, premature disk failure and consequent loss of data can be catastrophic. To mitigate the risk of failures, cloud storage providers perform condition-based monitoring and replace hard disks before they fail. By estimating the remaining useful life (RUL) of hard disk drives, one can predict the time-to-failure of a particular device and replace it at the right time, ensuring maximum utilization whilst reducing operational costs. We …

Self-Efficacy’S Mediating Role On The Relationship Between Personality And Depression In The Unemployed, Christina Tran

Master's Theses

Depression affects 1 in 5 unemployed individuals, holding rank as one of the most prevalent negative effects of unemployment in the United States. Personality is often considered a predictor of the development of depressive symptoms during unemployment however, there is little research to explain the relationship between personality and depression. The purpose of this study was to expand on the relationship between personality and depressive symptoms in the American unemployed population by testing self-efficacy’s mediating effect between personality and depressive symptoms in the American unemployed population. A sample of 121 participants, who were either currently or recently unemployed, completed an …

Confronting The Myths Of “Classical” Keyboard Improvisation: A Historical Evaluation, Examination, And Re-Incorporation Of Improvisation In Contemporary Piano Education And Performance, Kiefer Taylor

Master's Theses

Improvisation has been a highly valued skill in all periods of Western keyboard music. Many composers were also famous as keyboard improvisers and demonstrate the importance of improvisation as a tradition in “classical” keyboard performance. Strangely, today’s pianists, who perform the canonical eighteenth- and nineteenth-century works of these composers, no longer practice or incorporate improvisation into performance and instead play “only from the score.” Improvisation has also disappeared from the modern education of “classical” piano performers. Since improvisation was central to the performance practice of past keyboard repertoire, why does modern piano education not teach improvisation as a standard part …

An Exploration Of Dimensionality Reduction Of Dynamics On Lie Groups Via Structure-Aware Canonical Correlation Analysis, Wooyoung Chung

Master's Theses

Incorporating prior knowledge into a data-driven modeling problem can drastically improve performance, reliability, and generalization outside of the training sample. The stronger the structural properties, the more effective these improvements become. Manifolds are a powerful nonlinear generalization of Euclidean space for modeling finite dimensions. When additionally assuming that the manifold carries (Lie) group structure, this imposes a drastically stricter global constraint. The range of their applications is very wide and includes the important case of robotic tasks. We apply this idea to Canonical Correlation Analysis (CCA). In traditional CCA one constructs a hierarchical sequence of maximal correlations of up to …