Digital Commons Network^™

Empirical Comparsion Of Traveling Salesperson Approximation Algorithms, Shayan Daijavad

Master's Theses

The traveling salesperson problem deals with optimizing the route a traveling sales- person might take to visit a set of places exactly once and return back to their starting point. The problem is NP-hard, and it is hard to approximate in general, but special cases have many approximation algorithms, which come with tradeoffs. In this thesis we compare the runtime, approximation ratio, and overall implementation complexity of two approximation algorithms for the Euclidean version of the problem, a classical 2-approximation algorithm and the multifragment heuristic. We run both algorithms on randomly generated point sets and real world data from TSPLIB. …

Space Quacker Advanced Development (Squad): Lora Modulation On A Leo Cubesat Mission For Evaluation Of 916 Mhz Uplink, Samantha Brunton

Master's Theses

The LoRa Modulation format was developed by SEMTECH in 2018 and has revolutionized terrestrial Internet of Things (IoT) networks. LoRa (Long Range) has been successfully demonstrated as a long-range, low-data-rate communication modulation format and packet protocol for low-power terrestrial applications. LoRa offers low power consumption, low cost, robust signal sensitivity, and long communication range. Recently, interest has grown in using LoRa communication in Low Earth Orbit (LEO) satellite systems, especially for global IoT connectivity. Previous studies have investigated the theoretical feasibility and simulated the performance of LoRa satellite communication. Companies such as Lacuna Space have demonstrated the practical potential of …

Assessing Nitrogen Leaching Risk In Organic Vegetable Production, Megan Widle

Master's Theses

Nitrogen (N) leaching is the primary driver of groundwater contamination in agricultural regions. On California’s Central Coast, Agricultural Order 4.0 regulates this risk by constraining field-level N balances (N applied minus N removed). However, the assumption that unrecovered N is lost via leaching may not hold in organic and regenerative systems that promote soil organic matter accumulation. This study evaluated whether measured N leaching aligns with estimates derived from partial N budgets in organic systems, and whether management practices (intercrops, cover crops, and reduced tillage) can mitigate leaching risk. Four field trials were conducted to investigate N dynamics in organic …

Evaluating The Commercial Aquaculture Potential Of The Native Pacific Littleneck Clam (Leukoma Staminea) As A Climate Resilient Alternative To The Non-Native Manila Littleneck Clam (Ruditapes Philippinarum)., Skylar M. Wuelfing

Master's Theses

The California shellfish industry’s near-exclusive reliance on the non-native Manila littleneck clam (Ruditapes philippinarum) creates an economic vulnerability to climate-driven disturbances, which can cause mortality events that eradicate up to 80% of stocks. This singular reliance on an introduced species highlights a need for the evaluation of native alternatives like the Pacific littleneck clam (Leukoma staminea). Our goal was to assess the feasibility of using the native Pacific littleneck in commercial aquaculture by comparing their performance to the non-native Manila littlenecks across the following conditions: 1) a five-month field outplant trial at high and low intertidal …

Pedagogical Perspectives Of Practitioner-Turned-Instructors In Upper-Division Computer Science Courses, Sinchana Shivaprasad

Master's Theses

Computer science and software engineering are disciplines in which a substantial proportion of graduates enter software engineering careers immediately after completing their undergraduate degrees. However, research continues to highlight a persistent gap between the knowledge acquired in university settings and the practical skills necessary to succeed in industry. Faculty who bring prior industry experience may be well-positioned to help bridge this gap by integrating applied perspectives and real-world problem-solving into academic instruction. As professors with practitioner experience are being hired into computer science departments, there remains limited research exploring how their professional backgrounds influence teaching approaches and shape computing education. …

Thermally Induced Color Changes In Iron Oxide Containing Coatings, Tabatha Whitfield

Master's Theses

Wildland-urban interface (WUI) fires and residential conflagrations present significant challenges for post-fire damage and fire propagation analysis. CAL FIRE observed reddening in architectural coatings during the 2025 Pacific Palisades fire with no determination of the cause. While heat-induced color change of infrastructure coatings has been studied, its potential use as a thermal exposure indicator in residential fire events remains largely unexplored. The objective of this study was to characterize the heat-induced color change of yellow iron oxide containing coatings subjected to thermal exposures, replicating residential fire conditions. The coatings were applied to commonly used building materials and exposed to direct …

Implementation Of A Line-Scan Camera Triangulation Sensor For A Ball Balancer, Jackson R. Mclaughlin

Master's Theses

Ball Balancer or Ball on Plate systems are used for education and research in control theory. These consist of a plate which can be actively tilted, with a ball rolling on the surface. Students are challenged to model the dynamics of the system and implement a control loop which is capable of stabilizing the ball by actuating the plate.  The mechatronics group at Cal Poly is developing hardware for one of these ball-balancer systems, for future use in the Mechanical Engineering curriculum.

The position of the ball relative to the plate must be measured in order to control and stabilize …

Practice-Oriented Seismic Design And Retrofit For Mid-Story Isolated Buildings, Luke Reilly

Master's Theses

This study reviews the state of the art of MSI and evaluates a practical framework for preliminary design using coupling coefficients. A database of 155 research documents is compiled and classified into analytical, mixed numerical, computational, experimental, and miscellaneous studies. The review identifies major research trends, common modeling approaches, important design parameters, and remaining limitations. In addition, 16 representative MSI building projects are reviewed. These applications show that MSI is most often used for retrofit, vertical expansion, mixed-use buildings, over-track construction, and buildings with major functional or structural discontinuities. The study then examines the Coupling Coefficients (CCs) Method as a …

A History Of The Underground Comix Scene: The Seriousness Of An Unserious Genre, Harris Darcie Shugart

Master's Theses

The Underground Comix Scene of the 1960s and 1970s was born out of an age of censorship. The Comics Code Authority, a regulatory body created by the Comics Magazine Association of America in 1954, established guidelines requiring publishing houses to self-regulate following a recommendation from the United States Senate Subcommittee on Juvenile Delinquency in 1953. Comix with an X, for their X-rated nature, represent an emerging counter-culture in the latter half of the 1960s and the 1970s, with an epicenter of San Francisco. These comix and their artists were not interested in obtaining the looming ‘Seal of Approval’ from the …

Evaluating The Cost-Benefit Tradeoffs Of Simt Control Mechanisms In Resource-Constrained Gpus, Nikolas Tambornini

Master's Theses

This thesis conducts a hardware-level analysis of the cost–benefit tradeoffs associated with increasingly complex SIMT control mechanisms in a resource-constrained GPU core. Four design implementations are evaluated: a Base Tiny GPU without warp scheduling capability; a Warp Scheduler using round-robin warp selection; a Branch Divergence implementation incorporating a dedicated divergence stack and post-dominator reconvergence mechanism; and a Dynamic Warp Allocation implementation that replaces the static warp structure with a runtime warp manager, regrouping threads by current program counter to recover SIMD lane utilization during active divergence. Each design is evaluated using two complementary measurements: functional simulation implemented using the CocoTB …

Synthesis And Characterization Of A Graphene Oxide-Zif-8 Composite For Enhanced Post-Combustion Carbon Capture, Sydney Cooper

Master's Theses

Carbon dioxide (CO₂) emissions from fossil fuel combustion are a major contributor to climate change and its associated environmental impacts. The current standard technology for post-combustion carbon capture, aqueous amine scrubbing, is effective but requires significant regeneration energy and has high operational costs. As a result, solid sorbents have been investigated as lower-energy alternatives. Metal-organic frameworks (MOFs) are a promising class of porous nanomaterials due to their high surface area, tunable pore structures, and adjustable surface chemistry. Among them, zeolitic imidazolate framework-8 (ZIF-8) has high thermal and chemical stability, hydrophobicity, and favorable adsorption properties. However, conventional synthesis methods often rely …

Boundary Influence In Truncated Groundwater Models: Reconstructing A Local-Scale Modflow Model From A Consultant-Developed Regional Model In The Monterey Subbasin, Bruce K. Liscomb

Master's Theses

Regional groundwater models built by consultants contain valuable calibrated frameworks but are often too large and complex for repeated local-scale analysis. Rather than rebuilding an entirely new smaller model, this study truncates the existing consultant-built regional model of the Monterey Subbasin, preserving the original grid structure and parameter framework while reducing the active domain to a manageable size for planning-level use. A key finding is that boundary-condition representation exerted a dominant influence on simulated groundwater behavior within the truncated domain, highlighting that truncation is a structural decision that meaningfully affects how the model responds. Model performance was evaluated two ways. …

The Effects Of Carbon-Fiber Plates And Peba-Based Midsole Foam In Running Shoes On Lower-Limb Joint Kinetics And Kinematics In Recreational Female Runners, Jordan M. Allen

Master's Theses

The recent increase in long-distance running participation and the rapid advancement in footwear technology have created a need for research on injury prevention in this growing population of recreational runners. When “super shoes” were first introduced to the running scene, they caught the attention of runners worldwide with the rapid improvement in marathon performance [1]. Today, every major running brand offers its own version of a super shoe, each incorporating a carbon-fiber plate and PEBA-based midsole foam. While previous studies have shown the performance benefits of these shoes, a gap remains in the literature regarding how they impact knee, hip, …

Simulation Of Powder Spreading For Metal Additive Manufacturing, Florence Duff

Master's Theses

The powder recoating process for Laser Powder Bed Fusion requires iterative experimentation to develop the correct process parameters that will result in high quality parts. There currently lacks good spread quality metrics and models for optimizing spread quality. A machine that simulates the powder spreading process was built to streamline the process of selecting process parameters for specific types of powders without having to operate the full laser system. The parameters investigated were the layer thickness and spreading speed. The response variables were metrics developed to assess spread quality: the percentage of the build plate covered by powder and the …

Evaluating Design Choices For Gpu-Accelerated Finite-Difference Time-Domain Simulation On Resource-Constrained Devices, Joel Manesh

Master's Theses

The Finite-Difference Time-Domain (FDTD) method is a numerical technique for solving partial differential equations. It was first developed to solve Maxwell’s equations for electromagnetic wave propagation and has since been extended to model other physical phenomena governed by wave propagation. Because the FDTD method is data-parallel, it is well-suited for GPU acceleration; modern FDTD-based simulations run offline on large GPU clusters. There is, however, very little research on running FDTD on resource-constrained embedded GPUs, which are increasingly popular for real-time applications.

This thesis explores a CUDA-based FDTD solver for the 3D wave equation on the Nvidia Jetson Orin Nano. This …

Evaluation Of Laser Doppler Flowmetry And Transillumination Laser Speckle Contrast Imaging To Measure Blood Flow Change In Ischemia Mouse Hindlimb Models, Simon Park

Master's Theses

Peripheral Artery Disease (PAD), caused by plaque buildup and narrowing of the arteries, reduces blood flow to the extremities. Promoting collateral arteriogenesis can help redirect blood flow. However, simple growth of collaterals may not be enough to reverse PAD. Instead, the ability for the collaterals to vasodilate and control blood flow is important, meaning assessing collateral function is important for the arteriogenesis assesment. Although microscopy techniques can measure vasodilation, contrast limitations in larger vessels such as collaterals make blood flow measurements difficult. Techniques such as ultrasound or magnetic resonance imaging (MRI) can measure blood flow but have limitations with cost …

Computational Modeling To Evaluate Bipolar Flexible Electrode Designs For Use In Sciatic Nerve Stimulation, Krystyna S. Allman

Master's Theses

Peripheral nerve stimulation is clinically used to manage pain, rehabilitate motor function, and promote nerve regeneration. The sciatic nerve is often studied for stimulation due to its accessibility and clinical relevance. A conventional nerve cuff electrode is the least invasive method for nerve stimulation, but the mismatch of mechanical properties of the electrode with the nerve tissue can cause damage to the nerve and the electrode itself. This study investigated a novel bipolar, gold nanowire-based cuff electrode design and its ability to selectively activate fibers in the rat sciatic nerve at varying interelectrode spacings. In COMSOL, A finite element model …

Effect Of Viscoelastic Materials On Laminated Composite Beams For Vibration-Sensitive Automotive Enclosures, Nathan D. Neugeboren

Master's Theses

This study evaluates high-damping composite laminates for vibration-sensitive automotive components, with emphasis on motorcycle instrument clusters, the dashboard that houses the speedometer, indicator lights, and other rider information. Cantilever beam specimens were used as simplified test articles to compare analytical Euler-Bernoulli beam predictions, Autodesk Nastran finite element analysis, and sine-sweep experimental measurements. Metallic beams were first tested to validate modeling assumptions, FEA setup, and laboratory procedures. Analytical and FEA natural frequencies agreed within 0.6 % for ideal bonded metal beams, establishing a baseline for modal prediction. The method was then extended to carbon fiber, fiberglass, Kevlar, and hybrid laminates, with …

Development And Verification Of An Updated Thermal Model For Cal Poly's Small Thermal Vacuum Chamber, Bryce G. Leonard

Master's Theses

This thesis discusses modifications made to the Small Thermal Vacuum (TVAC) Chamber in the Space Environments Laboratory at California Polytechnic State University, San Luis Obispo, and the development and verification of an updated thermal model reflecting these changes. The chamber was redesigned to improve thermal performance, featuring a homogeneous aluminum platen coated with Aeroglaze Z306 to enhance radiative heat transfer, along with expanded data acquisition capabilities for temperature and pressure measurements.

A new thermal model of the chamber was developed in SolidWorks using a finite element approach. The model incorporates conductive and radiative heat transfer mechanisms and is configured to …

Trace: Temporal Rhetorical Analysis And Consistency Evaluation For Legislative Speech, David Hernandez

Master's Theses

Legislators frequently discuss the same policy issues across multiple hearings and legislative sessions, sometimes maintaining consistent positions and other times modifying or reframing their stance over time. Understanding how these positions evolve is important for analyzing political discourse and democratic accountability, yet identifying such shifts at scale remains difficult.

We introduce TRACE (Temporal Rhetorical Analysis and Consistency Evaluation), a system built on the Digital Democracy Database (DDDB) for detecting rhetorical inconsistency in California legislative hearing testimony. TRACE organizes utterances into speaker-anchored timelines indexed by bill and session, then applies hybrid semantic retrieval — combining dense BGE embeddings with BM25 lexical …

Lora Networking Hardware Reference Designs For Terrestrial And Low-Earth-Orbit Communications, Kevin Nottberg

Master's Theses

The work presented here demonstrates a highly robust and tested LoRa networking hardware reference design to meet the needs of the embedded networking company OWL Integrations. The hardware presented integrated a unique combination of features and design choices. The detailing of its unique design is potentially of use to others for use in fielded battery powered terrestrial sensor networking hardware utilizing LoRa. Also, the terrestrial hardware presented is shown to have the capability to support command and control (C2) LoRa links in low-earth orbit beyond terrestrial systems. The design presented has a more U.S. centric component bill-of-materials (BOM), with the …

Analysis And Design Of Auger Cast Piles With Isolation Casing, Zachary Lindsay

Master's Theses

This research addresses the analysis and design of double cased piles. Bay Area Rapid Transit (BART) runs a large rail system both above and below ground that connects the entire Bay Area. BART requires that all new constructions avoid transmitting axial load to their tunnels from adjacent piles. If piles fall within the zone of influence, builders must install double cased piles. Double casing is where there is an extra casing around the pile, with an air gap between them. The air gap prevents load from transferring to the outer casing. The length of this casing is called the isolation …

Short Arc Angles-Only Initial Orbit Determination For Reliable Reacquisition Of Low Earth Orbit Objects, Isabella Rackemann

Master's Theses

Low Earth orbit (LEO) is becoming increasingly congested, furthering the need for accurate tracking and catalog maintenance. Initial orbit determination (IOD) is the first step in this process, providing a preliminary estimate of an object’s state given observations. When it comes to LEO optical observations, a large portion of them are inherently short in duration. Angles-only IOD methods struggle with this data, often producing highly inaccurate solutions that limit reacquisition capabilities. This study expands on prior short arc IOD research, testing seven classical and assumed circular orbit (ACO)-modified angles-only IOD algorithms on real LEO observational data spanning 0-4 degrees of …

Design And Parametric Study Of A Mems-Based Reservoir Computer For Reinforcement Learning, Andrew P. Carr

Master's Theses

Single-node reservoir computing (RC) is a hardware-efficient approach to machine learning, leveraging the dynamics of physical systems. In this work, two reinforcement learning algorithms, Q-learning and Proximal Policy Optimization (PPO), are applied to a simulated micro-electro-mechanical system (MEMS)-based reservoir computer to solve both discrete and continuous control tasks. MEMS-based reservoirs are low-power, compact, and their natural frequencies (kHz to MHz) pair well with real-time control loops. To explore the relationship between reservoir dynamics and learning performance, a parametric study is conducted on two reservoir hyperparameters, reservoir size and neuron separation, using CartPole-v1 and MountainCar-v0. The RC successfully learns multiple tasks …

Design For Repairability: Analyzing The Evolution Of Smartphone Repairability To Generate Design Insights, Pranav Peddinti

Master's Theses

Smartphones are a major part of daily life, allowing people to communicate, browse the internet, shop, and enjoy entertainment. However, smartphones tend to be replaced quickly and therefore contribute to the growing electronic waste problem. The lifecycle of a smartphone can be extended by designing them to be more repairable, making it easier for owners and users to perform the repairs themselves. By only replacing failing components, the device can be in use longer, reducing the waste and pollution generated by replacing the device entirely. Therefore, product designers and engineers must focus on designing smartphones to be more repairable. Design-for-repairability …

Alford Loop Antennas For Ultra-High Energy Neutrino Detection, John K. Kimura

Master's Theses

The neutrino is a fundamental particle of matter emitted by high energy phenomena, such as supernovae and black holes. Detecting neutrinos can give scientists information regarding the frequency of high-energy cosmic events, as well as point them towards specific high-energy events. Ultra-high energy (UHE) neutrino interactions in Greenland ice result in electromagnetic pulses between 200MHz and 800MHz. The Radio Neutrino Observatory - Greenland (RNO-G) seeks to observe the resultant electromagnetic waves. The Alford Loop antenna is proposed to detect these emissions, because of its dipole-like radiation pattern, horizontal polarization, and adequate dimensions to fit in a 10" diameter ice borehole. …

`Youdrawitr`: Integrating Interactive Graphical Testing Into The `Ggplot2` Ecosystem, Alisa Krasilnikov

Master's Theses

`youdrawitR` is an R package inspired by the New York Times ‘You Draw It’ series, where readers are invited to sketch their own predictions before seeing the actual data. In a similar spirit, `youdrawitR` allows users to draw predicted values directly onto statistical graphics, creating a more engaging way to study how people interpret visual patterns. Earlier versions of the tool required knowledge of JavaScript D3 to extend or adapt the package, which created a barrier to entry for many statistical researchers. Further, the package was limited in scope, supporting only scatterplots. The redesigned `youdrawitR` builds on the familiar `ggplot2` …

Thermally Induced Color Changes In Iron Oxide Pigments Used In Architectural Coatings, Han Diep

Master's Theses

The 2025 Palisades Fire was one of the most destructive wildfires in the history of Los Angeles, destroying thousands of structures and severely impacting the communities after. This widespread destruction demonstrated an urgent need for more effective wildfire prevention strategies. Architectural coatings do not only provide aesthetics and protection against environmental conditions but can also function as a thermal indicator when a fire breaks out. This study examines the thermally induced color transformation of iron oxide pigments, commonly used in earthtone paint, to provide information relevant to CAL FIRE for improved analysis of wildland-urban interface (WUI) fire behavior and mitigation …

Controllable Tile-Based Level Generation For Vertical Platformers, Aiden P. Smith

Master's Theses

Procedural Content Generation (PCG) has had much research poured into it in recent years, as it is a way to more easily create content and levels for player replayability. Historically, this type of level generation has been done by algorithms with strict rules and black-and-white decision making. However, in recent years Large Language Models (LLMs) have been fine-tuned for this task in research in games such as Super Mario Bros and other 2D platformers. In this thesis, we apply a similar approach to level generation for a vertical platformer called Kid Icarus. We create a tile-based level generation system that …

On The Number Of Ways To Express A Set As A Union Of Individually Interesting Sets, Alison Watson

Master's Theses

In a dataset that contains what ought rightly to be several distinct datasets placed in juxtaposition with each other, grouping datapoints based on observed similarities can be done in many ways. Topological Data Analysis (TDA) is a field of math that seeks to impose geometric structure onto datasets, thereby translating problems in statistics to problems in geometry or topology. A common truism in this field is “Data has shape and shape has meaning.” In this thesis, we use combinatorial and categorical arguments to demonstrate some shortcomings of a TDA approach on a class of inverse problems inspired by marine wildlife …