Digital Commons Network^™

Juvenile And Subadult Gulf Sturgeon (Acipenser Desotoi) Use Of The Pascagoula River Estuary, Sarah Stovall

Master's Theses

Gulf Sturgeon (GS) are an anadromous species currently listed as “Threatened” under the Endangered Species Act. They reside in habitats across the northern Gulf of Mexico including coastal rivers, estuaries, and marine waters, making annual migrations between freshwater and marine habitats for spawning/summer resting and feeding, respectively. Since past studies prioritize adult movement, understanding how and when juvenile and subadult GS use the Pascagoula River estuary (PRE), a complex, bifurcated river delta federally designated as critical habitat is necessary to improve conservation efforts. My thesis assessed juvenile and subadult GS use of the PRE across four years (2020-2024) by analyzing …

Cutting Mechanisms And Control Systems Required For Precision Cutting With An Autonomous Lettuce Harvester, Aidan V. Fischer

Master's Theses

43% of California’s vast land is consumed for agricultural production to feed the United States and other nations Lettuce production alone brought in over $3 billion in 2022 in California. Most of the lettuce today is still harvested by hand using large groups of seasonal laborers; however, this has become increasingly difficult with an immigrant labor shortage. The objective of this study was to design a low-cost autonomous lettuce harvester prototype and evaluate the performance of the harvester capable of harvesting romaine lettuce preciously on a raised bed.

The harvester is equipped with an electrohydraulic control system that is used …

Real-Time Network Simulations For Ml/Dl Ddos Detection Using Docker, Luis D. Garcia

Master's Theses

As the integration of artificial intelligence (AI) within cybersecurity continues to

grow, machine learning (ML) and deep learning (DL) models are increasingly used to

detect cyber attacks. However, these models are rarely evaluated in real-time attack

scenarios to see how subtle changes from the real networking environment can affect

their predictions. To address this issue, we propose a scalable, platform-independent

Docker testbed specifically designed for simulating real-time Distributed Denial of

Service (DDoS) attack scenarios that allows researchers to deploy and evaluate their

pre-trained, ML and DL detection models. Our framework is simple to configure

and can run across Intel and …

The Application Of Generative Ai For Sketch-To-Image Conversion, Jeremy J. Kozlowski

Master's Theses

Sketches have historically been the primary way to identify individuals when images are unavailable. Most commonly, this appears in a police investigation, where the police release a sketch to the public in an attempt to find a suspect. However, sketches occasionally do not provide much detail due to the limitations of both the witness and the artist. A poor sketch greatly hinders the public’s ability to identify someone, decreasing the chances they will be found. To improve upon this inefficient way of identifying individuals, we propose a new pipeline that leverages deep generative artificial intelligence models to create detailed images …

Peer Collaborative Networks In Undergraduate Computing Classrooms, Noah T. Ravetch

Master's Theses

Peers are an invaluable resource for students at undergraduate universities. Many factors can impact how students form connections, some of which are tied to the students’ identities. While social networks have been studied in the context of universities, little research has been done specifically about peer collaboration and even less in the context of computer science classes. Our research aims to gain an understanding of how peer networks form in computing classes and the effect of being involved in one on students’ academic performances. We collected survey data (n = 139) about students’ peer collaborative behaviors in computer science classes. …

Performance Of Multi-Composite Materials With Corrugated And Cell Geometries Under Low-Velocity Impact, Lukas S. Kolbl

Master's Theses

Composite structures have demonstrated great potential to improve mechanical performance in various applications, including ballistics protection. This study demonstrates that the integration of geometrically optimized composites into core-face sheet assemblies provide great impact resistance. The research investigated the performance of two composite manufacturing methods under low-velocity impact through residual strength and damage comparisons. Corrugated core composites were produced with traditional manufacturing methods, namely compression molding, using twelve stacking sequences. These stacking sequences were chosen to represent four laminate groups, where a unique fiber orientation scheme was employed across three laminate thicknesses (6, 8, and 12 layers). In contrast, honeycomb and …

Finite Element Analysis And Verification Of Transverse Mechanical Properties Of Generally Cylindrical Orthotropic Constitutive Modeling Of 3-Phase Nanocomposite Unit Cell, Christopher J. Hawkins

Master's Theses

Fiber-reinforced composites are increasingly popular due to their specific strength and stiffness, making them ideal for high-performance applications. However, these materials primarily exhibit superior properties in-plane, while their out-of-plane characteristics remain comparatively weaker. Previous research has shown that the most effective method to enhance out-of-plane properties involves the incorporation of carbon nanotubes. Experimental tests have demonstrated significant improvements in properties such as tension, flexural, short beam shear, and fracture toughness. Alongside these experimental studies, analytical equations have been developed to predict the behavior of these composites under various loading conditions, including tension, bending, shear, and fracture. Existing models primarily address …

Bonsai Merkle Tree Streams: Bulk Memory Verification Unit For Trusted Program Verification System, Richard J. Rios

Master's Theses

Today, all modern computing systems are undoubtedly vulnerable to numerous types of attacks that could be targeted toward any layer of the system from dedicated hardware to highly abstracted software. Unfortunately, many devices and systems naturally contain inadequately protected components or software modules that un- dermine their security as a whole. Additionally, security is heavily variable system to system, and has a huge dependence on adequate implementation and ongoing support from device and software manufacturers. To address these various security issues in a very general way, TrustGuard, a containment security system utilizing an external device called the Sentry that would …

Photophoretic Optical Particle Trapping Improvements Using Beam Reflection, Ian A. Garcia, Xiaomin Jin Phd., Kun Hua Phd.

Master's Theses

Current research has shown that photophoretic optical trapping (POT) is a promising method for creating true three-dimensional holograms. A landmark study by Smalley et. al. at BYU was able to generate a full hologram within a 2 cm edge cube with remarkable success. However, a key drawback to this method is its poor ability to hold trapped particles within the focal point of the laser for an extended period of time. An investigation from our group presented at SPIE Photonics West 2023 sought to improve these results by varying the focal length of the trapping and the wavelength of the …

Investigating The Conversion Of A Signalized Intersection To A Turbo Roundabout, Vyshnavi P. Shetty

Master's Theses

Turbo roundabouts are multilane roundabouts that utilize a spiral design with raised lane dividers to guide traffic flow effectively. While they have seen widespread use in Europe, California is the second state in the US (after Florida) to have installed a turbo roundabout. Turbo roundabouts separate the ingress and circulating lanes. The concept was first proposed and implemented in the Netherlands to address safety concerns and improve traffic flow efficiency on conventional multilane roundabouts.

This research evaluates the first-ever turbo roundabout in California and compares its safety and operational performance with the previously existing 4-legged signalized intersection. The research team …

An Investigation Into The Use Of Amateur Astronomy Equipment For Optical Orbit Determination Using A Mobile Telescope Platform, Johan C. Govaars

Master's Theses

The process of optical orbit determination has long been in the domain of large organizations and stationary observatories with highly specialized scientific equipment. This thesis seeks to determine not only if satellites can be captured regularly using purely commercial-off-the-shelf (COTS) equipment, but also if initial orbit determinations can be made using that data. Moreover, the use of a mobile telescope platform allows users to circumvent the restrictions of fixed observatories such as low horizon viewing restrictions or existing light pollution.

A completely COTS setup was utilized that included an 8-inch Celestron NextStar 8SE telescope with an f/6.3 focal reducer and …

Joseph Moxon: Fueled By Science, Extinguished By Class. How A Forgotten Middle-Classed Early Modern English Puritan Printer Mathematician And Globe-Maker Helped Forge The Scientific Revolution And Democratize Knowledge Among The Trades, Kenneth L. Macro Jr.

Master's Theses

Joseph Moxon, raised within the trades, elevated into the middle-class, was an inducted Fellow of the Royal Society, Hydrographer to the King’s Most Excellent Majesty, Printer, Author, Translator, Maker of Globes and of Spheres, Maker of Maps and of Mathematical Instruments, Engraver, and Entrepreneur. Moxon was the quintessential Renaissance Man. A tradesman living in a time of great scientific intrigue and discovery, Moxon, acknowledged by few mid-seventeenth century historians, rightfully contributed his scientific discoveries—in the forms of tutorials and manuals written for the common man—as a testimony to all printers who have helped in the progression of the Scientific Revolution. …

Ultrasound Denoising And Speckle Reduction Using Artificial Neural Networks, Mark Atttaalla

Master's Theses

This paper focuses on improving speckle reduction and denoising performance in ultrasound images by leveraging neural networks. A dataset of simulated ultrasound images was created using Field-II simulation software based on CT scan images, to create clean and noisy image pairs. Various Convolutional Neural Network models based on U-Net and generative adversarial networks were developed and tested. Peak Signal-to-Noise-Ratio (PSNR) and Structural Similarity Index Measurement (SSIM) were used as metrics along with qualitative assessment. Results show that our tuned U-Net generator network outperformed traditional filtering such as Lee and BM3D.

Modeling Hourly Storm Surges Using Deep Learning Techniques, Md Abu Zafor

Master's Theses

Storm surges cause coastal flooding, one of the most devastating coastal hazards. Accurate modeling of storm surges is essential for predicting and mitigating these impacts. Traditional approaches model surges at individual tide gauges and often focus on daily time scales, leading to data redundancy and limiting their ability to capture sub-daily variability. This study addresses these limitations using deep learning (DL) algorithms to model hourly surges simultaneously at multiple tide gauges along the U.S. East Coast and Gulf of Mexico. Three algorithms, Convolutional Neural Network (CNN), Long Short-Term Memory (LSTM), and a hybrid ConvLSTM are employed to model surges using …

Exploring Customer Behavior Through Emotion Detection, Darlington Omoifo

Master's Theses

This thesis investigates the potential of emotion detection, gaze tracking, and hand movement analysis as tools to enhance understanding of customer behavior in retail environments. In retail, subtle indicators such as facial expressions, gaze direction, and hand gestures provide valuable insights into customer preferences and decision-making processes. The study leverages real-time video processing with a multithreaded approach on a Raspberry Pi-powered system embedded in a gift cart equipped with dual cameras. Using FER for emotion detection and a custom model for gaze and hand tracking, this research identifies customer engagement patterns, focusing on how emotions like happiness correlate with purchasing …

Dynamic Knowledge Elicitation: Leveraging Student Feedback For Improved Language Model Distillation, Reuven Muller

Master's Theses

Large Language Models (LLMs) have significantly advanced the field of natural language processing but remain resource-intensive and impractical for many organizations. Specialist models offer a viable alternative, often developed through Knowledge Distillation (KD) techniques. However, traditional KD methods rely on predefined static datasets to elicit knowledge from the teacher model, failing to dynamically address the weaknesses of the student model during training. This research introduces two novel methods for adaptive knowledge elicitation: Feedback-Driven Question Generation and Agent-Based Targeted Question Generation. These methods iteratively expand the training dataset based on the student model’s performance, leveraging a teacher model to generate targeted …

Techno-Economic Analysis Of Waste Plastic Gasification, Henrik Don-Yor Ketting

Master's Theses

The increasing generation of plastic waste and its environmental impact has driven interest in alternative disposal methods such as gasification. This study presents a techno-economic analysis of the gasification of waste plastics, specifically polypropylene (PP) and polyethylene (PE), to produce syngas. A two-stage process—thermal decomposition followed by steam reforming—was simulated using Aspen Plus. The simulation results were validated against experimental data available in the literature. The economic analysis was conducted by estimating the capital and operating costs of the gasification plant, considering factors such as feedstock costs, energy requirements, and syngas purification systems. Net Present Value Calculations were used to …

Are College Students' Grocery Shopping Habits Consistent With The Mediterranean Diet Guidelines? A Preliminary Report, Montana Grace Ayala

Master's Theses

The number of people diagnosed with cardiovascular disease, hypertension, obesity, and diabetes mellitus continues to grow. The Mediterranean diet has been shown to reduce the risks of developing heart disease. Fruit and vegetable consumption is low across the country. Improving fruit and vegetable consumption for adults might start with improving intake earlier in life because it can influence better food habits. Following the Mediterranean diet at a young age can prevent chronic diseases from developing. It is well known that college students have diets that are not consistent with healthy eating habits and can be influenced by the need for …

Experimental And Numerical Investigation Of Droplet Dynamics In Microscale Systems: The Influence Of Surfactants And Nanoparticles On Environmental Applications, Negin Bahadori

Master's Theses

Emulsions are suspensions of droplets dispersed into an immiscible liquid phase, with at least a water phase and an oil phase. The capability to incorporate both hydrophilic and hydrophobic components makes emulsions amenable to a variety of applications, such as bilgewater treatment and oil recovery. To optimize bilgewater treatment or oil recovery, many aspects must be considered, such as the effect of emulsion stability, the wetting conditions and, more in general, the possibility to characterize droplet’s behavior over static or dynamic conditions. This thesis investigates the roles of surfactants and nanoparticles in understanding droplet behavior in oil-water systems, with a …

Machine Learning-Driven Process Analysis And Optimization In Solid-State Welding And Fusion-Based Additive Manufacturing, Radif Uddin Ahmed

Master's Theses

In the modern era of advanced manufacturing, optimizing process parameters is pivotal in ensuring the quality and reliability of sophisticated component fabrication. This study presents a novel, data-driven approach to parameter optimization in two cutting-edge manufacturing techniques: Friction Stir Welding (FSW) and Laser Powder Bed Fusion (LPBF). By leveraging machine learning methodologies, this research addresses the critical challenge of efficiently determining optimal process parameters, a task traditionally relying on time-consuming and resource-intensive trial-and-error methods. This study will lead to a robust data-driven framework for process analysis of more advanced manufacturing techniques like the Additive Friction Stir Deposition (AFSD) process. Friction …

Effect Of Specimen Size On The Tensile Properties Of Selective Laser Melted Ti-6ai-4v, Timothy L. Tan

Master's Theses

Metal additive manufacturing (MAM) is a burgeoning industry. It is capable of manufacturing metal components with fine, intricate features and enables localized microstructural control. Due to its fine resolution and compatibility with common engineering alloys, selective laser melting (SLM) is one particular MAM process popular in academia and industry. The biomedical and aerospace industries have shown exceptional interest in the capabilities of SLM with the alloy Ti-6Al-4V. Because SLM Ti-6Al-4V components are aimed for use in critical applications, it is necessary to understand how SLM processing characteristics affect final part performance. One characteristic of SLM Ti-6Al- 4V that requires further …

Active Tectonics, Erosion Rates, And Topographic Metrics In The Hayword-Calaveras Fault Zone, Simone I. Yeager

Master's Theses

In northern California, the complex geometry of the San Andreas Fault system, and how it steps and propagates across the Earth’s surface, is revealed in the topography. Activity along the Mission and Arroyo Aguague oblique reverse faults, located where the right-lateral Hayward Fault steps to the left of the Calaveras Fault, are manifested in the Diablo Mountain Range. The high topography in the restraining step can be observed in lidar imagery and seismicity studies show these faults are connected at depth. In this study, we investigate active tectonics, erosion rates, and topographic metrics from the southern end of the restraining …

Enhancing Cross-Cultural Communication In Low-Resource Language Conversational Agents, Hardi V. Trivedi

Master's Theses

Recent advancements in natural language processing (NLP) and large language models (LLMs) have facilitated the development of systems capable of generating human-like responses across a wide range of tasks. However, the majority of research has focused predominantly on English, overlooking the vast linguistic diversity globally. For true global inclusivity, extending research to other languages is crucial, particularly as it can significantly benefit various sectors such as business, healthcare, government, and education. A major challenge in this expansion is the scarcity of digital data available and the limited number of pre-trained models for low-resource languages. Our research specifically addresses these challenges …

The Impacts Of Recreational Infrastructure On Mammal Use Of Riparian Zones In Northern California Regional Parks, Emily A. Matthews

Master's Theses

Public lands have been important for the protection of riparian habitats; however, many public lands are also used for recreation, which can reduce mammal habitat use. Understanding how mammals are affected by recreation in riparian areas can help guide management decisions. The goal of this research is to understand the effect of recreation on mammal use of riparian habitats in two popular East Bay Regional Parks, Charles Lee Tilden and Wildcat Canyon, and to map the extent of that impact. Cameras were deployed in the riparian areas of a high, moderate, and low development site (Alvarado, Tilden, and Wildcat Canyon) …

The Moderating Role Of Meaningful Work On The Relationship Between Loss Of Self-Identity And Psychological Well-Being In Retired Collegiate Athletes, Sarah M. Kurd

Master's Theses

Collegiate athletes are a focal point for many universities. These student-athletes work most of their lives to make it to the university level. Many collegiate athletes aspire to make it to the professional level after they graduate from college, but only a rare handful make it to the top. The rest of the athlete population retires and is placed into a world of “normalcy,” but the transition out of athletics can be very challenging, impacting a person’s psychological well-being. Most of these athletes will have to work a professional job after leaving sports. The present study aimed to examine the …

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 …

Using Noninvasive Calibrated Cuff Plethysmography To Observe The Effects Of Diabetes On Arterial Compliance, Jadon Bradford

Master's Theses

The prevalence of cardiovascular disease is on a continuous exponential growth across the globe. Thus, research into the underlying factors, effective methods of diagnoses, and preventive measures is necessary. Endothelial dysfunction is an early detector of cardiovascular diseases and can be used to inform people of preventative measures and early treatments before any extreme medical conditions occur. Something that is also on the rise and closely linked with cardiovascular disease is diabetes. There have been many past research studies that show the impact of diabetes on cardiovascular disease and more specifically endothelial dysfunction. A calibrated cuff plethysmography device is a …

Hypoxic Incubator: Improving Robustness/Reliability And Demonstrating Physiological Efficacy, Damon Dennis Tan

Master's Theses

The Microphysiological Systems Laboratory aims to develop colorectal cancer tumor models under a hypoxic environment to assess model response to pharmaceutical compounds in vitro. To perform relevant studies, researchers have attempted to use different hypoxic inducing strategies such as a nitrogen pod and hypoxic incubator to recreate in vivo physiological responses to hypoxia. However, studies would be interrupted due to incubator functionality failure. To ensure successful and physiologically relevant studies, I improved and verified the robustness and reliability of a hypoxic incubator previously designed and manufactured in the lab. Through the testing and iterating design processes, I engineered and implemented …

3d Printed Microfluidic Fabrication Methodology, Characterization, Mechanical Design, And Applications In Electrostatic Artificial Muscles And Benthic Microbial Fuel Cells, Terak B. Hornik

Master's Theses

The fabrication of microfluidic devices often requires specialized methods. The development of these methods requires careful characterization and understanding of the processes involved. Using primarily PolyJet 3D printing technology, microfluidics offers a wide scope of applications such as microfluidic benthic microbial fuel cells (MBMFCs) and electrostatic artificial muscles. MBMFCs benefit from the confinement of the microbes resulting in close proximity between the electrode and the organisms. Using a modular design called the Sponge, assembly and upscaling is possible. Electrostatic artificial muscles benefit from a microfluidic approach due to the non-linearity of electrostatic attraction creating disproportionate benefits when miniaturized. When designed …

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 …