Engineering Commons^™

An Empirical Study On The Capability Of Large Language Models In Learning Causality, Joseph Bergin

Electrical Engineering and Computer Science Undergraduate Honors Theses

Large language models (LLMs), including Google’s Gemini, OpenAI’s GPT series, and Meta’s Llama, have driven remarkable advancements in artificial intelligence, achieving complex, human-like performance across many fields. These transformer-based models are skilled at processing and generating many types of textual information, enabling them to perform a variety of tasks. However, an important question remains about their actual capacity to grasp causal relationships—whether these models can truly differentiate between causal directions or simply respond based on learned patterns. This thesis tests this ability by evaluating LLMs on tasks created to test their understanding of causal, anti-causal, and third-party reasoning. We conduct …

Striking A Balance: Market Shock & Responses In Automotive Components Manufacturing, Emma Lane Mcgahey

All Theses

This thesis examines the effects of extreme market shocks on supply chain dynamics within the automotive industry. Through an analysis of demand data from an automotive manufacturer to its component suppliers (January 2018 to May 2024), the study investigates the relationship between market shocks and supply chain responses, providing insights into how auto components inventory management handles downstream responses to market shocks. With supporting public data—from FRED, BLS, and the U.S. Census Bureau resources—we explore two primary relationships: the impact of market shocks on the Average Standard Deviation of Demand (SDO) and the effect of demand variability on expedited pricing …

Interpreting Strain Caused By Transient Well Testing, Soheil Roudini

All Dissertations

Understanding reservoir properties and structure is essential to managing subsurface operations, such as geologic storage of CO₂ or production of water, hydrocarbons or heat. Previous work demonstrated the potential of analyzing strain data during transient well tests by estimating hydraulic diffusivity using a type-curve-like approach. The following dissertation aims to pursue this potential by developing and evaluating methods for interpreting strain tensor data to improve subsurface characterization. The research advances the classic, intuitive method of using type-curves to interpret well tests, but it also brings together modern computational methods from machine learning, proxy modeling and Bayesian inversion, and it …

Rover Chassis & Suspension, Nikki Zainer, Aung Bhone Zaw, Joelle Romero, Colin Thompson

Mechanical Engineering

The Mars rover project is part of the University Rover Challenge (URC), a robotics competition organized by the Mars Society that tasks student teams with designing and building the next generation of Mars rovers. Cal Poly Human Space Technology and Research (CP-HSTAR) has inherited a rover developed by a previous senior design team.

This report documents the progress made in refining the rover’s structure, highlighting key specifications, and detailing design improvements aimed at enhancing the suspension’s structural integrity, improving wheel traction, increasing modularity, and developing an enclosed chassis for electronic components.

This report includes a detailed breakdown of the rover’s …

Investigating Challenges Of Converting Cad Models To Game Ready Assets, Vathsa Pawar

All Theses

This thesis explores the challenges associated with converting detailed CAD models into game-ready assets optimized for use in virtual reality (VR) environments using game engines, focusing on enhancing using mechanical engineering models. The primary goal is to establish a toolchain that allows the integration of CAD models into game engines for immersive applications, enabling engineers and stakeholders to interact with 3D models in a synthetic environment. The study employs several test cases ranging from simple door models to complex automotive vehicle prototypes, elaborating the process of exporting CAD models through intermediate formats (such as STEP, STL, GLB) using tools like …

Influence Of Hygrothermal Conditions Of The Bistability Of Asymmetric Carbon Fiber Laminate Composites, Celia Hill

All Theses

Carbon fiber-reinforced polymer (CFRP) laminates have widespread use in many industries because of their exceptional strength-to-weight ratio. Carbon fiber laminates following an asymmetric layup orientation can exhibit bistability meaning the laminate can exist at two stable geometric configurations. The morphing characteristics of bistable CRFP has a growing level of interest because of its potential in various applications including space aircraft structures for easy repair, automotive structures for energy dissipation and ergonomics, robotics for flexible motion and energy harvesting. Existing research shows that both moisture and temperature affect the material properties and behavior of CFRP laminates, however, the influence of moisture …

Co2 Capture Utilizing Novel Deep Eutectic Solvents: Modeling, Process Simulation, And Cost Analysis, Nazneen Aspi Kolah

Masters Theses

One of the most pressing global issues that humans face is climate change caused by anthropogenic greenhouse gas emissions, especially carbon dioxide (CO2). Conventional solvents utilized for CO₂ capture, such as amines, are widely used in industrial applications due to their high CO2 absorption capacity. However, deep eutectic solvents (DES) have attracted a lot of academic attention recently due to their biodegradability and low energy for regeneration.

This research serves as a foundational proof-of-concept for using DESs in industrial gas separation processes. Five DES are evaluated for CO2 removal from flue gases. Aspen Plus is utilized to simulate the performance …

Perceptual Hash Based Content Matching, Nicholas Daniel Chenevey

Master's Theses

The proliferation of video content and AI generated imagery has introduced a number of new challenges in content identification and verification. The ability to trace content back to its source has become a critical problem as video content increases both naturally and synthetically through AI generation. This thesis provides the design, analysis, and experimental verification for a perceptual hash based framework aimed at addressing these challenges. Perceptual hashing is a method for encoding the visual content of images into compact and easily comparable binary strings. This process is used as the foundation for content matching in videos and source verification …

The Integration And Validation Of A Class 3b Laser For Stereo Particle Imaging Velocimetry, Jensen Lam

Master's Theses

Particle Imaging Velocimetry (PIV) is a laser flow diagnostic measurement technique used to measure spatial and temporal velocity fields. In an effort to promote experimental aerodynamic research, specifically an entry point for students to learn Particle Imaging Velocimetry, an in-house Class 3B laser PIV system was developed and its experimental results were verified with a Class 4 laser. Both systems were integrated on the Cal Poly Water Tunnel Laboratory. The work emphasizes the application of lasers controlled by a micro-controller to perform microsecond-based pulses and integrating a newly-developed device with an old system consisting of software, cameras, and synchronizers. The …

Design, Manufacturing, And Assembly Of Modular Snake-Like Robotic Arm, Alongside Design And Implementation Of System’S Digital-Twin, Scott Brown

Master's Theses

A unique modular snake-like robotic arm, also referred to as MA\RS – the Modular Arm \ Robotic System - was designed, manufactured, assembled, simulated, and programmed to create a modular robot which could move to a desired end position given the number of links, the position of the end link and the duration of motion. This robotic arm serves as the start of research into a modular space robotic system to be used in low-gravity environments. As such, this project focused on developing the initial design of the robot and its digital twin. The system’s modularity allows for changes to …

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 …

Cytotoxicity And Genotoxicity Of Glyphosate And Roundup Quickpro On Chinese Hamster Ovary Cells, Tasnimul Ferdous

Graduate Theses and Dissertations

Glyphosate and Roundup products have become the most used herbicide worldwide. However, previous bans in Europe and recent reversal have caused confusion over their safety. This study aims to investigate the cytotoxic and genotoxic effects of Roundup QuickPro and its main ingredient glyphosate using Chinese hamster ovary (CHO) cells. Cytotoxicity was calculated by measuring CHO cell viability with 72 hours of exposure to each toxicant. Roundup exhibited higher cytotoxicity with LC50 of 511.2 μg/mL than glyphosate’s LC50 of 3389 μg/mL. The recommended application concentration (11,233.7 μg/mL) of Roundup QuickPro is much higher than the measured LC50, which caused complete cell …

A Novel Interpretation Of Average Run Length For Assessing The Performance Of Control Charts, Gonçalo Sousa

Masters Theses

The Average Run Length (ARL) is a performance measure of Control Charts widely used within Statistical Process Control. In this study we propose a new approach for the computation of the ARL that is based on a novel interpretation of out-of-control signals produced by a Control Chart. Specifically, out-of-control signals used to calculate traditional ARLs may correspond to Type I errors and may not reflect a Control Chart’s true performance. To compensate for this issue, for Shewhart and EWMA charts, constraints are applied to the calculation of ARLs so that only out-of-control signals that occur when the corresponding statistic is …

Field Evaluation Of Transverse Post-Tensioning And Latex Modified Concrete On Bridge Load Distribution, Paige Waters

All Theses

The Airport Road Bridge (ARB) over Rocky Creek in Greenwood, SC is one of 377 channel bridges in South Carolina currently load-posted, limiting vehicle weight and potentially restricting access to vital services. The South Carolina Department of Transportation (SCDOT) seeks a cost-effective method to strengthen these bridges and enhance their load-sharing capacity.

Through live load field testing, this research seeks to use two retrofitting techniques – transverse post-tensioning (PT) and latex modified concrete (LMC) overlay – to determine whether or not channel bridges can be improved. Direct tension testing was also performed to evaluate the substrate-overlay bond of the LMC …

The Effect Of Pressure Gradients On Perceived Discomfort, Zachary Bush

All Theses

Introduction:

A pressure gradient is where high and low pressure meet. It is responsible for displacement and irritation of the skin commonly caused by tight bandages, bracelets, or socks. The irritation is at the edge where the skin is displaced by the high and low pressure. An analysis of the effect pressure gradients have on discomfort would have significant medical relevance for any device, fixture, or clothing pressed against the skin at high pressure. This primarily includes prosthetic and orthotic devices.

The bottom surface of the heel provides a naturally circular, uniform pressure profile. This makes it the optimal testing …

Ellipticity-Controlled Exceptional Points From Nanoscale Metasurfaces, Benjamin Goldberg

McKelvey School of Engineering Graduate Student Theses & Dissertations

Precise control over light polarization is critical for advancing technologies in telecommunica- tions, quantum computing, and image sensing. However, existing methods for manipulating polarization around exceptional points in non-Hermitian systems, have exclusively focused on circular polarization and work with reflected light. To address this limitation, we de- velop a novel metasurface platform with high-Q resonators that enables tunable control of polarization exceptional points across arbitrary ellipticity for transmitted light. Our design uses orthogonally polarized guided mode resonators in a two-layer silicon metasurface, where careful tuning of the dipolar guided mode resonances (DGMRs) and layer spacing allows us to control the …

Basic Safety Message Generation Through A Video-Based Analytics For Potential Safety Application, Abyad Enan

All Theses

With the advancement of modern artificial intelligence techniques, computer vision can play a vital role in enhancing roadway safety by reducing the risk of imminent collisions. To do so, a vision-based safety application is required, where a roadside camera can monitor the roadway traffic and predict potential risks of crashes in real-time. If any risky situation or behavior is observed that may lead to a crash, then a safety application can send warnings to the vehicles at risk. For vision-based safety applications on a roadway section, it is important to accurately monitor each vehicle’s location, speed, acceleration, heading direction, etc. …

Assessing The Potential For Photosynthetic Degradation Of Per- And Polyfluoroalkyl Substances, Marlow Thomas

All Theses

PFAS is a prevalent groundwater contaminant. It has been known to cause many health issues for humans and animals including cancer and several diseases. A main problem faced with PFAS is contamination in groundwater. Remediation strategies have been and continue to be researched to try to mitigate this issue. Current treatment strategies to mitigate PFAS include the use of granular activated carbon, ion exchange, chemical oxidation, and many hybrid treatments. There has not been one treatment technology to date that has prevailed as the best due to monetary and time constraints.

The main intention behind this research is to examine …

Comparative Analysis Of Design-Build And Design-Bid-Build Project Delivery Methods Through Cost, Schedule And Quality Performance For Warehousing And Storage Facilities, Vijaya Ravi Prasanth Reddi

All Theses

Storage facilities are essential for e-commerce operations, providing inventory, distribution, and delivery space. As per the Bureau of Labor Statistics, the number of warehousing and storage businesses in the United States increased from 15,152 in 2010 to 21,287 in 2024, showing continuous growth over the decade. Given the recent surge, there is a need to understand the performance of these facilities better. This study aims to contrast the measure of quantitative performance of design-build (DB) versus traditional design-bid-build (DBB) project delivery methods (PDM) based on cost, schedule, and quality metrics for storage facilities. This research conducted a literature review to …

Pressureless Sintering Of Sic - Oxide Multiphase Ceramics For Protective Coating Applications, Reilly Boros

All Theses

For hydrogen-fueled combustion, there exists a demand to improve coating materials that are capable of protecting SiC_f/SiC CMC turbine material. Promising coating materials must be able to shield from harsh oxidation while working at extremely high temperatures. The work presented in this thesis aims to expand the understanding of two promising material systems for integrated environmental barrier coating (EBC) – thermal barrier coatings (TBC) by fabricating bulk composite ceramic samples and performing characterization to further understand their sintering behaviors. In this study, a processing procedure to consistently produce dense composite ceramics of PDC SiC – Y₂Si …

Toward Electrochemical Detection Of Salmonella Enterica Serovar Enteritidis On Hydroponically Grown Green Onions (Allium Fistulosum L.), Lisseth Casso-Hartmann

All Theses

The Food and Drug Administration (FDA) established standards during the growing, harvesting, packing, and holding of produce for human consumption as part of implementing the Food Safety Modernization Act (FSMA). One of the main requirements for farmers is to detect environmental pathogens such as Salmonella enterica species in water and sprout samples. S. enterica is a bacterium of significant concern due to its pathogenicity and ability to survive and persist in diverse environmental conditions. S. enterica has been associated with recalls in ready-to-eat foods. Traditional detection methods include Enzyme-Linked Immunosorbent Assay (ELISA), Polymerase Chain Reaction (PCR), and plate counting, which …

Fatigue Endurance Of Alsi10mg Post Hip Heat Treatment With High Duration Thermal Aging, William Venable Newcomb

Open Access Theses & Dissertations

AlSi10Mg is one of the cornerstones of additive manufacturing (AM), with its materialproperties and relatively low cost making it extremely popular as an AM metal choice, specifically using Laser Powder Bed Fusion (LPBF). Many publications have focused on this material, studying tensile strength, fatigue, heat treatments, and more. However, an area that requires further study is the effect of aging on the materials fatigue properties, with this study examining an industry standard heat treatment of Hot Isostatic Pressing (HIP). Using studies that have already been completed, AlSi10Mg was fatigue tested at near 100% UTS and 75% yield strength after HIP …

Integrating Sustainability And Food Safety Through Quantitative Microbial Risk Assessment And Life Cycle Assessment Of Low-Moisture Foods, Jessica Bain

Graduate Theses and Dissertations

Food safety and sustainability are critical concerns in the food industry. However, these areas are often evaluated separately, leading to an incomplete understanding of the overall impact of food production on human health. This dissertation aims to integrate food safety with sustainability to provide a comprehensive assessment of the impact of low-moisture foods on human health, using the almond processing supply chain as a case study.

In addition to conducting life cycle assessments (LCA) of almond processing, wheat flour production, and dried apple processing, this dissertation aims to create a framework to bridge the gap between sustainability and food safety. …

Design And Optimization Of Matrix Core Transformer For High Power Bidirectional Isolated Dc/Dc Converter, Zhe Zhao

Graduate Theses and Dissertations

Thanks to the advancement of semiconductor technology, the silicon carbide (SiC) devices with high voltage and power capability are developed and widely used in several industry applications, e.g., gird-connected photovoltaic (PV) system, data center power supply, and electrical vehicle (EV) charging station. After the concept of solid-state transformer (SST) was proposed as an important solution to the medium voltage (MV) power conversion systems, this bidirectional isolated DC/DC converter has attracted much attention in academia and industry. One of the main advantages of SST is to improve both the power density and efficiency of the power conversion system by replacing the …

Investigating Functionalized Cvd Graphene Heterostructures As Platforms For Hydrogen Gas Sensing, Evans Asiedu Addo-Mensah

Graduate Theses and Dissertations

The hydrogen economy is rapidly advancing and is poised to become one of the world's largest economies, driven by the abundance of hydrogen gas. Several organizations, particularly in the United States of America, are closely or have been monitoring this development, with rapidly increasing interest. Considering that hydrogen gas has no taste, smell (odor), or color, and very combustible, it’s imperative to develop detectors and sensors capable of rapidly detecting leaks to prevent application disasters. Owing to its extraordinary mechanical and electrical characteristics, graphene is the material that has been studied the most. When combined with hexagonal boron nitride (hBN), …

An Automated Design Flow From Synchronous Rtl To Optimized Layout Using Commercial Eda Tools For Multi-Threshold Null Convention Logic Circuits, Cole Harrington Sherrill

Graduate Theses and Dissertations

This work presents the first automated design flow from synchronous RTL to highly optimized layout for Multi-Threshold NULL Convention Logic (MTNCL) circuits. The developed synthesis flow overcomes many of the drawbacks of existing attempts and leverages the advanced optimization features provided by modern synthesis tools. The remaining timing race conditions native to the MTNCL architecture have been identified and thoroughly explored. Two sets of novel timing constraints were devised: the first responds to these race conditions, yielding highly reliable MTNCL circuits; the second directly targets the critical paths within MTNCL circuits, allowing the designer to optimize the target circuit for …

Multimodal Spectroscopy To Study Tumor Microenvironmental Changes In Vivo, April Mordi

Graduate Theses and Dissertations

Every year there are millions of new cancer diagnoses and deaths worldwide. While great strides have been made in technologies and drugs for cancer treatment, there is still a need to understand tumor response to therapy as many patients still endure treatment failure after completing their treatment regimen. Current clinical imaging techniques for detecting response to therapy are utilized weeks to months after the course of treatment, and present limitations to measuring response during treatment. Optical spectroscopy techniques can help meet this need to determine the response of tumors to treatment as it allows for near real-time in vivo characterization …

Modeling, Synthesis, And Experimental Characterization Of Rhenium Disulfide For Optoelectronic Devices, Solomon Opeyami Ojo

Graduate Theses and Dissertations

Two-dimensional (2D) transition metal dichalcogenides (TMDs) have garnered considerable interest for their potential in optoelectronics and photonics owing to their remarkable combination of electronic, optical, and mechanical properties. These characteristics distinguish them from other 2D materials, including graphene, making them particularly valuable for next-generation technologies. This dissertation focuses on ReS_₂, a 2D TMD with a unique anisotropic 1T distorted crystal structure. The research aims to elucidate its fundamental properties through a combination of theoretical modeling, material synthesis, and experimental characterization techniques, with the goal of optimizing ReS_₂ for device applications. A theoretical investigation utilizing Density Functional Theory …

Synthesis And Process Optimization Of Cellulose Nanocrystals From Miscanthus X. Giganteus For Commercial Viability, Jaspreet Kaur

Graduate Theses and Dissertations

Cellulose nanocrystals (CNCs), derivatives of an abundant biopolymer, i.e., cellulose, are emerging as promising alternatives to petrochemical-based products due to their unique properties, including biodegradability, low toxicity, high strength, low density, large surface area and low coefficient of expansion. CNCs have diverse applications ranging from food packaging and textiles to drug delivery and medical implants, etc. Despite their potential, the widespread commercialization of CNCs faces significant hurdles owing to the high environmental burden and production costs. They are mainly driven by the commonly used source utilized for CNC synthesis i.e., wood and the intensive synthesis process i.e., requirement of …

Two-Photon Imaging For Characterizing Tumor Microenvironmental Changes In Non-Small Cell Lung Cancer Associated With Metastatic Recurrence, Paola Monterroso Diaz

Graduate Theses and Dissertations

Lung cancer remains the leading cause of cancer deaths, comprising nearly 25% of all cancer deaths (Sung et al., 2021a). The five-year survival rate of patients with non-small cell lung carcinoma (NSCLC) remains significantly low given that over half present with locally advanced or metastatic disease at time of diagnosis, and experience tumor recurrence following therapeutic intervention (Tamura et al., 2015; Uramoto & Tanaka, 2014). Current evaluation techniques to assess treatment response are lacking, given they are implemented several weeks after treatment completion and are solely based on anatomical changes in tumor size, forgoing other criteria such as functional or …