Digital Commons Network^™

Determining K Clusters In K-Means Clustering With The Crab Algorithm, Jasmine Kristine S. Cabrera

Master's Theses

Unsupervised clustering often faces the challenge of determining the correct number of clusters in the absence of a true target variable. Traditional methods such as the Elbow Method and the Silhouette Score can produce ambiguous results and rely on assumptions about cluster shape or separation. To address this, we created the Clustering Rivals and Buddies (CRAB) algorithm which evaluates clusters based on stability across multiple subsamples. CRAB uses pairwise classifications to identify points that consistently group together called “Buddies” and points that remain separated called “Rivals.” Applied with K-means, CRAB accurately recovers underlying cluster structures in both spherical and non-spherical …

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 …

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 …

The Implementation Of Scintillation Detectors With The Cuore/Cupid Collaboration In The Search For Neutrinoless Double Beta Decay, Reese Sandra Cormier

Physics

CUORE (Cryogenic Underground Observatory for Rare Events) is an experiment at the Gran Sasso National Laboratory in Assergi, Italy, currently searching for an answer to the matter-antimatter asymmetry problem; the question: why do we exist? One proposed explanation is neutrinoless double beta decay, a theorized exotic decay that would prove that neutrinos are their own antiparticle, violating the current Standard Model for particle physics. However, current detection methods do not distinguish different types of particle interactions, resulting in alpha decays contributing to the background. Therefore, the experimental sensitivity is too limited to make confident determinations about the data. For this …

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 …

Stem Workshops For Pre-K Students, Sofia Berg, Ashlyn Swoboda

Architectural Engineering

This project involved the development and implementation of a four-part structural engineering workshop series for preschool-aged children at the Orfalea Children’s Center at California Polytechnic State University, San Luis Obispo. The workshops were designed to introduce fundamental structural engineering concepts through age-appropriate discussions, demonstrations, and hands-on activities focused on engineering careers, structural shapes, skyscrapers, and bridges. The lessons emphasized concepts such as stability, bracing, structural loading, seismic behavior, and iterative design while encouraging collaboration, creativity, and problem solving.

Throughout the workshop series, students actively participated in discussions, demonstrated enthusiasm for engineering activities, and were able to recall concepts introduced in …

Xenaforms: Reinforcing Kinematic Stability Through Rigid Connections, Katherine G. Thies

Architectural Engineering

XenaForms combine rigid planes and straight lines with the fluidity of structural origami to create beautiful, organic folded plate structures. Unlike many conventional structures, folded plate systems derive their stability from the interaction between connected panels, creating the appearance of a single continuous sheet of material. The XenaForm uses structural origami and triangulation to create stable points at the apex of two non-colinear triangles. While it is mathematically true that no moment needs to be transferred across the seam between panels in order to have a stable structure, allowing some moment capacity greatly helps during construction. Specifically, these stiff connections …

The Xenaform: Structure Through Geometry, Justin Tobias Mendoza Ocampo, Emily Marie Labrador, Banyan Walker, Paul Minchev, Brayden Sean Kelleher, Ethan Mario Ceccarelli

Architectural Engineering

The XenaForm is a geometry-driven structural system that incorporates complex forms generated from simple rules of stability, inspired by the work of Iannis Xenakis and reworked by Professor Edmond Saliklis. This project investigates how structural stability can be achieved through geometric configurations rather than a reliance upon material strength alone. By utilizing the design principles of trilateration and the interconnection of triangular panels, the XenaForm was constructed in accordance with the rules of the International Association for Shell and Spatial Structures Pavilion Competition. The team generated several design iterations and selected a final design to fabricate and construct, considering affordability, …

Microbial Literacy, Equity, And Sustainability At Cal Poly: A Policy Framework With University Housing As A Pilot Case, Joseph B. Fewel

Biological Sciences

Microorganisms play a fundamental role in human health, environmental systems, and the functioning of built environments, yet they remain largely absent from sustainability and public policy discussions. This project proposes a framework for integrating microbial literacy, equity, and health into institutional decision-making, using California Polytechnic State University (Cal Poly) as a case study and university housing as a pilot site for implementation. Drawing on interdisciplinary literature in microbiology, public health, environmental justice, and sustainability, as well as policy analysis and stakeholder interviews, this project examines how campus systems, including housing, ventilation, sanitation, food systems, and waste management, shape microbial exposure …

Catalyzed Chemical Recycling Of Pet Plastic Waste, Irfan Oyon Chowdhury, Caiden Scott Figlioli

Materials Engineering

Plastic waste accumulation and continued reliance on fossil fuel-based polymer feedstocks remain major challenges in the plastics industry. While mechanical recycling is widely used, repeated thermal processing, contamination, and polymer degradation reduce recycled plastic quality. Chemical recycling offers an alternative by depolymerizing plastics into reusable monomers that can produce materials with properties closer to virgin plastics.

This study investigated the glycolysis of post-consumer poly(ethylene terephthalate) (PET) using ethylene glycol to produce bis(2-hydroxyethyl) terephthalate (BHET). Zinc oxide (ZnO) nanoparticles were synthesized by solution precipitation and used with 1-butyl-3-methylimidazolium chloride ([Bmim]Cl) as a co-catalyst system. PET glycolysis was performed using 2.00 g …

Elastic Actuator For Robotic Leg, Bruce Berg, Allan Pham, Madeline Slater, Sofie Zalatimo

Mechanical Engineering

The Cal Poly Legged Robots Group (CPLRG) is developing a 12 degree of freedom robot with the goal of eventually performing highly dynamic movements such as jumps and flips. During such movements, large impact forces will be experienced by the leg, potentially resulting in damage to physical components such as the motors. The scope of this project is to integrate elastic elements into the quadruped legs to reduce shock loads on the motors and improve the efficiency of the legs through energy storage. The key stakeholders for this project are Professor Charlie Refvem and Dr. Simon Xing. Other stakeholders include …

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 …

Experimental Methods For Cryogenic Rare Event Detection: Cuore And Cupid, Alessandro Libenson

Physics

This senior project was written with the primary purpose of serving as a introductory guide for undergraduate students learning about the experimental methods used in the CUORE and CUPID Collaborations. In particular, this project is geared towards getting students in Dr. Gutierrez's research group at Cal Poly up to speed on what CUORE and CUPID actually do. I wrote this as an undergraduate aiming to help future undergraduates. For Cal Poly students, I would suggest the following prerequisites before reading this paper: Electronics and Instrumentation, Quantum Laboratory 1, and the equivalent of the coding/analysis class. It is also important to …

Elevate Grill, Tanner Bachmann, Lance Anderson, Caden Huang, Jonathan Li, Brady Alexander

Mechanical Engineering

Santa Maria-style grills are a defining cooking tool of California’s Central Coast and are valued for their open fire cooking method and adjustable grate height. While this design provides direct control over cooking conditions, maintaining a consistent cooking temperature requires frequent manual adjustment of the grate position. This process relies heavily on operator experience and continuous attention, making temperature consistency difficult to maintain in a commercial kitchen environment. The Elevate Grill project was developed for Mike Ahrens and Wren Provisions to address this challenge while preserving the traditional Santa Maria grilling experience. The system uses temperature feedback from multiple thermocouples …

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 …

Crab: A Novel Clustering Score Using Clustering With Rivals And Buddies For Unsupervised Learning, Allen Choi

Master's Theses

Unsupervised clustering algorithms today are used across a wide variety of fields such as biology, engineering, and industry in order to classify observations into groups where labels are not provided. This can provide important latent information regarding the observations within groups, as well as insight regarding the groups themselves. In order to judge the optimal number of clusters for an unsupervised clustering algorithm, many methods exist such as the Elbow Method and Silhouette Score; however, these methods come with drawbacks and are not necessarily flexible across many unsupervised methods. We present a novel clustering score framework relying on a resampling-based …

Marine Heatwaves And Fish Reproduction: Endocrine Responses In The Eurythermal Sheepshead Minnow (Cyprinodon Variegatus), Isabel Villafuerte

Master's Theses

Marine heatwaves associated with climate change are increasing in frequency and severity, posing significant threats to fish populations in shallow habitats such as estuaries and salt marshes. Because temperature is a primary regulator of fish reproduction, understanding how heatwaves affect reproductive physiology is critical for anticipating the biological consequences of ongoing climate change for coastal fishes. Here we examined how simulated heatwave conditions affect the reproductive hypothalamic-pituitary-gonadal (HPG) endocrine axis in the estuarine sheepshead minnow (Cyprinodon variegatus), a eurythermal fish well suited to studying thermal stress responses in estuarine environments. Adult sheepshead minnows acclimated to a daily oscillating …

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 …

50,000 Spectra And Counting: Preparing For A Roman Spectral Atlas, Maya Jordan Seagraves

Master's Theses

Slitless spectroscopy with the Hubble Space Telescope's Wide Field Camera 3 \linebreak (WFC3/IR) enables simultaneous spectral coverage of all sources in a field, but large-scale single-orientation datasets remain challenging to process. We developed a pipeline that automates HSTaXe spectral extraction across hundreds of Hubble Space Telescope observations, enabling efficient processing of 84 fields and producing over 50,000 spectra from three filters (F110W, F125W, and F160W) and two grisms (G102 and G141). This was achieved by creating a companion Python package, the Module for Infrared Label Analysis (MILA), that integrates data calibration, extraction, and visualization. To assess the scientific utility of …

Analyzing A Hot Player: A Holistic Approach To The Hot Hand, Faran Igani

Master's Theses

This paper develops a continuous-time, continuous-state framework for studying “hot hand” performance within NBA games. Rather than defining performance in terms of discrete shot outcomes or short streaks of makes and misses, it tracks a player’s contribution using John Hollinger’s Game Score continuously throughout the game. The Game Score metric aggregates multiple on-court contributions through weighted in-game statistics, evolving as play progresses. This approach allows for the construction of a single metric that indexes a player’s performance over the course of the game. To evaluate whether observed within- game surges reflect genuine “heat” rather than random variation, a simulation-based null …

Optimization Of Repeat Ground Track Constellation Design For Complex Discontinuous Regional Coverage, Paige Jewell

Master's Theses

The continued growth of low Earth orbit (LEO) satellite constellations motivates efficient constellation design methods to reduce cost and complexity. Although brute-force methods are commonly employed in the preliminary design of satellite constellations, pairing analytic methods with optimization algorithms provides a more efficient means of searching the design space. Constellation design for continuous global and regional coverage is well-established; however, strategies for discontinuous regional coverage remain underdeveloped. This thesis focuses on an analytic geometry-based method for computing satellite coverage and revisit metrics, coupled with genetic algorithm optimization to efficiently explore the design space. The viability of this method is shown …

`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` …

Integer Quantization And Embedded Deployment Of Cnn Star Trackers For Cubesats, Meora R. Giusiano

Master's Theses

A star tracker determines spacecraft orientation by photographing the star field, detecting stars in the image, matching them against a catalog, and computing the rotation between observed and cataloged directions. Convolutional neural networks (CNNs) have been proposed as replacements for the detection and centroiding stage, offering improved sub-pixel accuracy and recovering faint stars that classical thresholds lose to stray light and sensor noise. The improvement comes at higher computational cost; the PolySat systemboard targeted in this work lacks the floating-point hardware these networks assume.

This thesis closes the gap between floating-point desktop evaluation and embedded integer deployment. Nine encoder-decoder CNN …

Evaluation Of Solar Reflective Pigments For Use In Direct-To-Metal Coatings, William J. Diment

Master's Theses

Solar reflective coatings offer a promising strategy to mitigate the urban heat island effect by reducing absorption of near-infrared solar energy. This thesis project investigates the feasibility of incorporating near-infrared reflective pigments into waterborne direct-to-metal (DTM) latex coating systems while maintaining acceptable color comparison characteristics and coating performance. An all acrylic latex DTM formulation with titanium dioxide as the sole pigment was prepared and tinted with a variety of conventional and solar reflective commercial colorants across the yellow, red, blue, and green color ranges. Coatings were evaluated for solar reflectance, CIELAB color, gloss, contrast ratio, rheological behavior, accelerated ultraviolet weathering …

What Makes A Modern Attention Implementation?, Brian H. Slonim

Master's Theses

Since the seminal assertion by Vaswani et al. in 2017 that “Attention Is All You Need,” transformer models have risen to ubiquity due to their ability to learn extremely complex patterns from sequence data, culminating in the unprecedented generative capabilities of large language models. These models’ strength lies in their scale: hundreds of millions (e.g., BERT-LARGE) to billions or trillions of learned parameters. Running inference with these models, let alone training them, would be intractable without significant innovations in the hardware and software that support them. This need has driven an enormous demand for GPU compute and associated software ecosystems, …

On M-Estimation: From Theory To Examples, Alexander Yuan

Master's Theses

M-estimation provides a unified framework for statistical procedures defined as optimizers of data-dependent criterion functions. This thesis gives an expository account of M-estimation in classical and high-dimensional settings. The classical part develops weak convergence, empirical process tools, and the argmax framework for studying consistency, rates of convergence, and weak limits. Examples including least squares, maximum likelihood, robust location estimation, change-point estimation, and empirical risk minimization illustrate regular and non-regular asymptotic behavior.

The high-dimensional part studies regularized M-estimators, where the focus shifts to finite-sample error bounds and model selection guarantees. Topics include decomposable regularizers, restricted strong convexity, non-convex penalties, and sparsistency. …

Hot Hands Or Chance Happenings? A Simulation-Based Approach For Wnba Teams, Ruben Jimenez

Master's Theses

The hot hand is a polarizing topic in basketball analytics: fans, stakeholders, and even players themselves assert confidently their belief or disbelief in the idea that players who perform well will continue to do so over an extended period of time. Statistical research has been conducted since as early as 1985 to attempt to disprove or prove the existence of this phenomenon. More recent works have refuted the earliest objections to the hot hand’s existence, with conclusions aided by robust simulation techniques. In this work, we compare hypothesis tests using multiple simulation techniques to explore the hot hand at the …

Is The Hot Hand Real? Evidence From A Permutation And Hierarchical-Based Analysis, Cameron Z. An

Master's Theses

The hot-hand phenomenon, often described as the tendency for individuals to experience prolonged streaks of success that exceed what would be expected under random performance, has been widely studied across many disciplines, particularly basketball. Early studies attempted to evaluate this effect through various techniques, often concluding that the hot-hand phenomenon was largely a myth. However, recent studies have begun to revisit previous analyses using improved statistical techniques, with some claiming evidence of a discernible hot-hand effect. This study examines the presence of the hot-hand effect in the modern NBA by testing whether observed shooting patterns deviate from those simulated under …

High-Resolution Queries, Low-Resolution Context: Scaling Vision Transformers With Asymmetric Spatial Reduction, James M. Dwyer

Master's Theses

Vision Transformers (ViTs) have demonstrated great performance on image classifica tion benchmarks, however, the quadratic complexity of the self-attention mechanism with respect to sequence length limits their scalability to higher resolution inputs. The attention score matrix grows as O(N2) in both compute and memory, where N is the number of patch tokens, making ViTs computationally expensive and memory intensive for applications that require real-time inference or operate under resource constraints.

This thesis investigates whether the key and value sequences of the self-attention mechanism can be compressed using the local spatial structure of the image — while keeping queries at full …

A Higher Order Panel Method With Vortex Particle Wake, Luca Flick-Kaiser

Master's Theses

Panel codes were some of the earliest methods for computing the flow around aircraft. Despite the availability of higher fidelity CFD methods, panel methods remain an essential tool for the development of modern aircraft, allowing engineers to quickly iterate during the conceptual design phase.

This work develops and implements a high order panel method using Python. The wake is modeled using vortex particles, resulting in an accurate wake representation with minimal user input. The integration of the higher order singularity distributions has been extended to include the calculation of the velocity gradients necessary for the vortex particle implementation. The use …