Digital Commons Network^™

Adjoint Enhanced Panel Methods, Christopher Sheehan

Master's Theses

This thesis describes the development, implementation, and validation of an adjoint-enhanced panel method for two-dimensional airfoil analysis. While conventional panel methods are computationally efficient for flow analysis, they typically rely on relatively computationally expensive finite differencing for gradient calculation in design optimization or sensitivity studies, a limitation addressed by employing the discrete adjoint method. The core of this work involves integrating the discrete adjoint method with a Hess-Smith panel code utilizing Class-Shape Transformation (CST) for airfoil parameterization, which requires the analytical derivation of sensitivities for panel geometry, boundary conditions, and the aerodynamic influence matrix with respect to the CST design …

An Evaluation Of The Relationship Between Beef Cattle Grazing Activity Traits And Conception Methods During The Breeding Season, Jason Dubowsky

Master's Theses

Efficient use of native rangelands and improved reproductive success are primary objectives in beef cattle production. Grazing behavior during the breeding season may be influenced by pasture characteristics, including size and water availability, as well as physiological differences due to reproductive status. This study aimed to evaluate the relationship between grazing activity and conception method in crossbred Angus cows over a 2-year period. The study was conducted during the winter months (December – February) on the Central Coast of California with a mean temperate of 53 degrees Fahrenheit. Cows (n = 76) were blocked by age and then randomly assigned …

Effect Of Seasonal Variability In Methane Emissions And Iron Redox Chemistry At Terrestrial-Aquatic Interfaces, Hermes C. Ruiz

Master's Theses

Methane (CH₄) emissions at terrestrial–aquatic interfaces (TAIs) are significant contributors to the global carbon budget, yet the mechanisms driving methanogenesis remain poorly understood. Limited data exist on how seasonal variations and redox processes influence CH₄ fluxes in these dynamic ecosystems. This study addressed two questions: (1) How are CH₄ fluxes in riverine floodplains and adjacent hillslopes impacted by seasonal variations? (2) What roles do metal redox processes (e.g., iron (Fe)) play in regulating methanogenesis?

In-situ CH₄ flux and solid-phase Fe speciation were quantified in East River, CO, under flooded and drained conditions. Groundwater chemistry, gas flux, and soil physical properties …

Exploring The Moderating Effect Of Boundary Management Strategy In A Remote Work Environment, Brandon M. Vasquez

Master's Theses

Remote work has evolved significantly, especially during the COVID-19 pandemic, and continues to influence employee experiences in both positive and negative ways. Managing the separation between work and personal life is of importance. More specifically, using a boundary management strategy of segmentation may be more effective than an integration strategy because those who separate the two domains of work and family/personal life may be less prone to conflict in their lives. The present study aimed to examine the moderating effect of boundary management strategy on the relationship between remote work and job satisfaction, work-life balance, and well-being. Specifically, it was …

Attention In The Age Of Tiktok: Examining The Cognitive Impact Of Short-Form Video Consumption, Samantha Shannon Sutrisno

Master's Theses

With the rapid growth of popularity among short-form video platforms such as TikTok, media consumption has shifted toward fast-paced and highly engaging formats. This trend raises questions about the potential effects of continuous exposure to brief and repetitive audiovisual stimuli on attention. Research on short-form video’s impact on attention is limited, but prior studies suggest it may influence attention in meaningful ways. This study examined the relationship between short-form video consumption and attention among TikTok users (N = 110) by using the Attention Network Task (ANT), which measures the alerting, orienting, and executive control networks of visual attention. Participants were …

Blenderized Tube Feeding Formulas: Attitudes, Barriers, And Clinical Benefits As Perceived By Registered Dietitians In Pediatric Care, Savannah Smiley Keeler

Master's Theses

Blenderized tube feeding formulas (BTFF) are increasingly recognized as a viable alternative to conventional commercial tube feeding formulas (CTFF) for pediatric patients requiring enteral nutrition. This cross-sectional, exploratory study aimed to assess the experiences, attitudes, and perceived clinical benefits of BTFF use among Registered Dietitian Nutritionists (RDNs) working with gastrostomy-tube-dependent pediatric populations in the United States. A total of 146 RDNs completed a 45-item online survey, which gathered quantitative and qualitative data on BTFF familiarity, feasibility, clinical outcomes, caregiver factors, and institutional barriers. Findings revealed that while BTFF use remains variable across clinical settings, 55.8% of RDNs reported increased utilization …

Evaluation Of The Performance Of The Traveling Wave Differential Element In Protective Relays, Niranjan Kc

Master's Theses

This thesis evaluates the dependability, security, and limitations of the traveling wave differential protection function (TW87) in modern time-domain-based protective relays, using a combination of simulations and hardware testing in a laboratory environment. Fault transients are first generated using the electromagnetic transients program model of a real, 230 kV, 65.7 km long overhead transmission line, which are then played back on real time-domain-based protective relays. Various fault scenarios are chosen to evaluate the impacts of factors such as fault inception angle, distance to fault from line terminals, fault type, fault impedance, and external faults on the relay functions’ performance. Results …

Eating Habits, Eating Behavior Mediators, Body Composition And Physical Fitness Among Rotc Cadets, Kaitlin Renee Hanks

Master's Theses

The physical and mental demands of the military and the requirement to maintain body composition standards make healthful eating essential to military service. Reserve Officer Training Corps (ROTC) cadets are a unique subgroup of the United States military, and the combined demands of their military training and educational pursuits may increase their susceptibility to unhealthy eating patterns. The purpose of this study is to describe the relationship between eating habits, eating behavior mediators, body composition, and physical fitness among ROTC cadets. This study used a cross-sectional design that included an online survey, an inperson body composition assessment, and carotenoid measurements …

Analyzing The Relationship Between Diabetes Duration And Self-Management In Adults With Diabetes, Caroline Noel Stroo

Master's Theses

Diabetes mellitus (DM) is a metabolic disease that affects 14.7% of adults in the United States (Centers for Disease Control and Prevention, 2023). Prevalence of diabetes increases with age, with rates for adults aged 65 and older reaching 29.2% (Centers for Disease Control and Prevention, 2023). Factors such as age, race, obesity, physical activity level, and genetics strongly increase the risk of developing type 2 diabetes (T2DM) (National Institute of Diabetes and Digestive and Kidney Disease, 2016). Diabetes requires complex and comprehensive management to reduce the risk of developing comorbidities (Al-Shabeeb et al., 2021). Factors such as education, familial support, …

The Design Of Coplanar Waveguide Traveling-Wave Kinetic-Impedance Parametric Amplifiers, Jordan Scott Savoie

Master's Theses

Astronomical observations and many physics experiments rely on cryogenic amplifiers for readout. Current sensitivity is limited by the noise figure of high-electronmobility transistor (HEMT) amplifiers, which have proven di!cult to decrease further in recent years. Traveling-wave kinetic-impedance parametric amplifiers (TKIPAs) are an emerging class of amplifiers which have the potential to substantially improve the sensitivity of microwave low-noise amplifiers (LNAs) while also accepting relatively high input powers and amplifying over a wide bandwidth. In this thesis, I present the design, modeling, and testing procedures for coplanar waveguide (CPW) TKIPAs developed by our group at the National Radio Astronomy Observatory. Using …

Lactation Management Training In Graduate Nutrition And Dietetics Programs: A Preliminary Report, Laura Ashton Gillin

Master's Theses

The American Academy of Pediatrics recommends exclusive breastfeeding (BF) for the first six months and continued breastfeeding for at least two years with complementary food. Despite this recommendation, only 24.9% of infants in the United States are exclusively breastfed at six months (Breastfeeding Report Card 2022). Breastfeeding support and lactation management are critical to promoting a successful breastfeeding experience. Specifically, qualified support from a Registered Dietitian Nutritionist (RDN) is recommended, yet graduate students in Nutrition and Dietetics do not receive adequate training regarding breastfeeding intervention. This study aimed to evaluate graduate Nutrition and Dietetic programs to determine the amount of …

Vitamin B12 Deficiency: Confidence, Perspectives, And Practices Among Registered Dietitian Nutritionists, Avery Miller Adams

Master's Theses

Vitamin B12 deficiency is common in the United States, occurring in 20% of adults aged 60 and above (Andres et al., 2004). Veterans are susceptible to B12 deficiency due to tobacco product usage, alcohol consumption, and poor diet quality. Megaloblastic anemia is the second most prevalent vitamin deficiency disorder recorded in military personnel from 1997 to 2015 (Knapik et al., 2021). This exploratory, analytic research aims to assess registered dietitian RDN nutritionists’ (RDN) knowledge, perceptions, and intentions regarding treating vitamin B12 deficiency in a clinical setting. Due to population prevalence differences, responses from VA and non-VA practicing registered dietitian-nutritionists (RDNs) …

Alameda Song Sparrow Habitat Use Of Salt Pond Restoration Sites In South San Francisco Bay, Bradley A. Speno

Master's Theses

Restoration is acknowledged worldwide as a conservation need to return ecosystem functions. However, projects require monitoring to track system changes and assess restoration progress. In the San Francisco Bay, several large restoration projects are implementing plans to return salt-producing ponds to the historical ecosystem, tidal salt marsh. The Alameda song sparrow (Melospiza melodia pusillula), a California species of special concern, has been documented to use restored and historic marshes, but their use of restored salt ponds is not fully understood. The birds’ use of restored marshes may be a useful measure of restoration progress. This research investigated the relationships comparing …

California Utility-Scale Solar Energy Land Use Impacts On Species And Ecosystems, Ingrid Salazar

Master's Theses

Utility-scale solar energy (USSE), defined as projects of at least 1 megawatt, is rapidly expanding in California, which generated 37.5% of its electricity from renewables in 2023, with 24% coming from solar. While USSE supports decarbonization, it can also cause environmental harm, including biodiversity loss, habitat fragmentation, and land conversion. This study uses ArcGIS Pro 3.4.0 and public environmental data to analyze the spatial distribution of USSE projects, land use changes from 2013 to 2023, and occurrences of at-risk species across California’s bioregions. USSE development is heavily concentrated in the Mojave Desert, San Joaquin Valley, and Colorado Desert, which are …

Riparian Restoration Increases Soil Microbial Biomass In Marin County Rangelands, But Soil Carbon Stock Is Less Responsive, Sherilyn Kathryn Reinhart

Master's Theses

Land use change has caused the degradation of 70% of the Earth’s soils, directly altering soil microbial communities and carbon cycling. Interest in carbon farming practices is growing, but studies that document the nuances of soil carbon flux in specific bioregions are still too few. In this study, I examined how one practice, riparian restoration, alters soil carbon stock and microbial community structure over time. Using a paired sampling time series design, I collected soil samples from twelve riparian forests and adjacent rangelands near Marin County, California. Young and mature sites ranged from five to 29 years since restoration, and …

Correlations Of Intersectional Identity Cohesion And Growth In Queer And Transgender Black, Indigenous, And People Of Color, Zoha T. Qader

Master's Theses

Past research has found that identity cohesion (how integrated multiple identities are) is a protective factor that moderates the relationship between intersectional microaggressions and mental health outcomes. Individuals with higher identity conflict (multiple identities clashing) had anxiety and depression symptoms that could be predicted by the distress they experienced from intersectional microaggressions. For those with high identity cohesion, this was not the case. While compelling, the question remains, what are the factors that contribute to identity integration versus identity conflict? The present study will utilize existing data of 417 QTBIPOC individuals. Ratings of LGBTQ+ community belonging and engagement, and LGBTQ+ …

Modeling Lensed Quasars With Neural Posterior Estimation: Complex Mass Models, Logan C. O’Brien

Master's Theses

The Vera C. Rubin Observatory is expected to discover ∼ 103 galaxy-scale strongly lensed AGN systems during its 10 year operation conducting the Legacy Survey of Space and Time (LSST). I use a machine learning neural posterior estimation method to automatically model these systems with the intention of using them for time-delay cosmography, to constrain the Hubble constant and, ultimately, the properties of Dark Energy. In the work shown here, the neural network that I utilize is trained on simulated lens systems with simple mass distributions that consist of a single main deflecting galaxy. I am testing the robustness of …

Learning Structure With Multivariate Information Bottleneck And Exploration Of New Methods In Sequential Decision Making, Volodymyr Makarenko

Master's Theses

Research in useful information extraction has been motivated by the increasing demand to extract insights from unstructured data, and by the need to store and transmit great volumes of information, often originating in unstructured data such as videos. Research in rate distortion and information bottleneck paved the path for understanding and guiding the design of lossy encoders, capable of extracting relevant information. Independently, research in deep representation learning has enabled numerous applications for unstructured high-dimensional data such as images. However, the interpretability of the deep learning methods remained limited. Several desired properties of learned representations have been suggested, including disentanglement. …

Post-Fire Succession In An Old-Growth Coast Redwood (Sequoia Sempervirens) Forest In The Santa Cruz Mountain Bioregion, Mojgan Mahdizadeh

Master's Theses

Fire is a common disturbance in the western United States, and variation in its frequency and intensity can significantly impact species recovery and distribution across ecosystems. While fire frequency and intensity are increasing in coast redwood forests, little is known about how this forest type responds to high-intensity wildfires. In 2020, a high-intensity wildfire burned large portions of the coast redwood forest in the Santa Cruz Mountains, including over 1,700 ha of old-growth. This event created a unique opportunity to evaluate post-fire succession. This research assessed vegetation recovery across high and low to moderate severity burned areas using random sampling …

Quantifying Erosion Rates Of The Mission Hills Along The Calaveras, Mission, And Hayward Faults In Northern California To Better Understand The Role Of Fault Geometry On Surface Topography, Ian Duncan Lord

Master's Theses

The San Francisco Bay Area lacks publications on erosion rates and their relationship to restraining bend fault geometry. This thesis presents a detailed geochronologic study of erosion rates from the Mission Hills along the Calaveras, Mission, and Hayward faults located northeast of San Jose, California. The goals are to provide erosion rate values where none currently exist and to gain a better understanding of how fault geometry influences topography along restraining bends. To quantify the erosion rate of these faults, river sediments containing 10Be were collected from 14 catchments using well-established protocols. Of the successfully processed samples, the erosion rates …

The Impact Of Early Life Experiences On Math Confidence, Nhu X. Hin

Master's Theses

Students form beliefs about their academic abilities through a combination of emotional experiences and early learning environments. While prior research has documented how math anxiety can undermine performance and how early experiences with math-typed activities can foster positive attitudes, less is known about how these factors collectively influence students’ math confidence. The present study investigates how math anxiety, engagement in childhood math-typed activities, and perceived support for math-related learning contribute to college students’ confidence in their math abilities. Participants (N = 102) completed self-report measures assessing each of these constructs. A multiple regression analysis revealed that the three predictors collectively …

The Anti-Work Attitude Scale: Conceptualizing And Measuring The Resistance To The Institution Of Work, Alayna Del Rosario

Master's Theses

Recent shifts in labor discourse have drawn attention to rising burnout, declining organizational commitment, and diminishing job satisfaction, which challenge traditional assumptions about the centrality and desirability of work. These tensions have given rise to the concept of anti-work, a growing discourse that questions the moral, economic, and psychological foundations of work itself. Despite its cultural relevance, anti-work remains largely undertheorized and unmeasured in empirical research. Drawing from interdisciplinary scholarship, this study defined anti-work as a negative critique of work as a social construct, questioning its value, purpose, and impact on individuals and society. Anti-work was operationalized through two higher-order …

The Relationship Between Hindrance Demands And Work Engagement: The Moderating Role Of Resilience, Adoré Davis

Master's Theses

The coronavirus pandemic decreased work engagement globally due to increased hindrance demands. Many organizations were motivated to increase work engagement, which is positively correlated with beneficial organizational outcomes. The intention of this study is to examine if personal resources like resilience moderate the relationship between hindrance demands and work engagement. Hindrance demands are refined from job demands and hindrance stressors, which are stressors that impede progress in employees. Resilience is a personal resource correlated with pro-social behavior, internal locus of control, and higher levels of empathy. Resilience as a personal resource has mainly been studied as a predictor of work …

Acoustic Presence Of Humpback Whales (Megaptera Novaeangliae) In U.S. West Coast National Marine Sanctuaries, John C. Barkowski

Master's Theses

Humpback whales are one of many species of marine mammal that utilize sound in multiple aspects of their lives in the oceans. By collecting acoustic data from multiple areas across the habitat of these animals, we can investigate spatiotemporal patterns in their sound production to better understand their life history strategy. This study uses three years of passive acoustic data collected concurrently from three U.S. West Coast National Marine Sanctuaries to look for spatiotemporal patterns in humpback whale song and non-song vocalizations. Additionally, this study investigated correlations between upwelling conditions and the onset of song to explore links between the …

Working Memory In Major Depressive Disorder: A Meta-Analysis Of Structural And Functional Brain Differences, Eunji Back

Master's Theses

Major depressive disorder (MDD) is one of the most prevalent mental health disorders in the US and is characterized by depressed mood and loss of interest. Many MDD patients also experience difficulties with executive function, including working memory. Neuroimaging studies reveal structural and functional brain differences between MDD patients and healthy controls that may underlie these working memory difficulties, but findings have been mixed. A quantitative synthesis of neuroimaging data through a meta-analytic approach offers a promising avenue to identify commonalities across studies. We conducted separate meta?analyses of structural and functional magnetic resonance imaging (MRI) data, with the latter focused …

Coloring Outside The Lines: Factors Facilitating Divergent Thinking, Michelle Baca Reinke

Master's Theses

Divergent thinking involves producing a multitude of unique and diverse ideas. The ability to “color outside the lines” is crucial to business, education, and social domains. The flexibility, originality, and fluency dimensions of divergent thinking are commonly assessed using the Alternative Uses Task, which involves generating uses for common objects. Prior research suggests that high identification (first-person perspective) with schema-inconsistent experiences increases flexibility, while semantic density (degree of conceptual associations) impacts originality and fluency inversely. However, their combined effects across multiple divergent thinking dimensions remain unexplored. The present research investigated the interactive effects of identification (high, low), schema consistency (consistent, …

Demographic Characteristics And Selected Personality Traits Of Women In Competitive Bodybuilding, Chloe A. Zeeuw

Master's Theses

This study investigated demographic characteristics and measures of personality (dimensions of performance perfectionism and five-factor model characteristics) in women in competitive bodybuilding between 18-25 years old. A total of 24 women completed an online survey which included a demographic questionnaire, the Five Factor Model Rating Form (FFMRF), and the Performance Perfectionism Scale for Sport (PPSS) inventories. Descriptive results for the FFMRF were Openness (18.17±3.12), Conscientiousness (25.58±3.33), Extraversion (19.96±3.46), Agreeableness (19.88±4.58), and Neuroticism (15.67±4.94), and for the PPS-S were Self-oriented performance perfectionism (20.96±3.53), Socially prescribed performance perfectionism (13.96±4.26), and Other-oriented performance perfectionism (10.54±4.23). Pearson’s correlation coefficients and Shapiro-Wilk tests revealed that …

Measurements Of Spinal Posture During Common Strawberry Picking Positions Using Inertial Measurement Units, Madeline E. Everson

Master's Theses

Physically demanding professions, such as agriculture, put people at an increased

risk for experiencing back pain. This is due to the awkward and harmful postures sustained

throughout their workday. While studies have been done demonstrating that back pain is

prevalent amongst this community, most do not collect motion capture (MoCap) data,

leaving the specifics of the kinematics, such as the amount of time spent in harmful

postures, unknown. Unfortunately, MoCap data is typically limited to that of a lab or

facility where the cameras are housed. Therefore, this study aimed to mitigate the

inaccessibility of traditional MoCap by validating that …

Integration And Testing Of A Quadruped Robot With Ros2, Jeremy S. West

Master's Theses

The Cal Poly Legged Robotics Group has been developing research and teaching platforms for agile legged robotics since 2020. These platforms are expected to provide students with opportunities to develop complete legged-robot systems from low-level control to advanced robotics tasks such as motion planning and decision making. However, the current prototyped quadruped robot lacked the software and sensing capabilities for high-level quadrupedal gaits and advanced robotic research.

To address these challenges, this project developed Switch, a robotic platform that builds upon the previous BRUCE platform with significant hardware and software upgrades. Switch features a modular design that allows individual software …

Development Of A Control System For An 8-Dof Quadrupedal Robotic Research Platform, Jack Butler

Master's Theses

Quadrupedal robots offer a versatile locomotion option that can extend the operating space of a robot into uneven terrains. However, controlling these systems presents significant challenges due to nonlinearities introduced by various factors.

In this thesis, model-predictive control (MPC) is applied to an 8-DOF legged robot developed by Cal Poly’s Legged Robotics group. The MPC framework employs a lumped rigid-body model that treats the robot as a single rigid body with forces applied directly at the foot contact points. The controller is developed within the ROS2 environment, with integration of state estimation and gait-pattern generation, to provide maximum modularity and …