Digital Commons Network^™

Sentry V3: Extending Context Switches On A Trusted Secure Coprocessor, Mark Kong

Master's Theses

Software correctness and integrity is only ensured through trust in the un- derlying hardware. However, modern computer systems are complex to design and secure. Thus, given the choice between performance and security, companies will often prioritize performance, resulting in vulnerable systems. This creates exploitable systems that must be patched retroactively because business value performance over security. One approach to this issue is to separate the root of security from the rest of the system to create a minimal trusted computing base. Trustguard is one instance of this. Trustguard implements a Containment Architecture with Ver- ified Output (CAVO) model which shows …

Optimizing Web Servers With Io_Uring, Mihika Nigam

Master's Theses

Modern web servers face unprecedented demands for high throughput and low latency [10] [11]. Yet, even the state-of-the-art optimizations often fail under heavy workloads on existing infrastructure. Despite advancements in hardware, communication between applications and the kernel remains a critical bottleneck.

Industry surveys reveal that over 50% of production servers still rely on traditional epoll-based architectures [5]. This research aims to investigate and characterize Linux’s new io_uring subsystem, which has the potential to overcome these challenges. Through controlled load testing of various existing architectures like event-driven, multi-process, and multi-threaded architectures (including other commercial servers), we demonstrate how io_uring can help …

Enhancement Of A Python Integral Boundary Layer Method, Jeffrey T. Azuma

Master's Theses

This thesis presents a series of additions to a Python based integral boundary layer software library known as PyBL. This library provides the user the means to calculate boundary layer properties using different models for boundary layer behavior. The additions feature the integration of a set of new laminar and turbulent integral boundary layer models originally developed for and currently found in the program XFOIL. These models were modified to fit the ODE solver method at the foundation of PyBL. A new method for PyBL that stitches a laminar and turbulent solution together has been developed to improve the ability …

Efficient Gan-Based Adversarial Example Generation Against Ml-Based Network Intrusion Detection Systems, Darren D. Hartono

Master's Theses

In the realm of network security, Network Intrusion Detection Systems (NIDS) are essential for identifying and mitigating malicious activities targeting networked devices. Traditionally, these systems have relied on signature-based and anomaly-based detection techniques. However, the increasing complexity and adapt- ability of cyber threats have driven the adoption of Machine Learning (ML) ap- proaches in modern NIDS, significantly improving their ability to detect a wider range of attack vectors. Despite these advancements, ML-based NIDS remain vulnerable to adversarial examples—deliberately crafted inputs designed to mislead models and trigger incorrect classifications. Originally identified in the field of computer vision, adversarial examples now pose …

Design And Development Of A Laboratory Star Tracker System, Kevin D. Iverson

Master's Theses

This thesis presents the design, calibration, and validation of a low-cost star tracker system and hardware-in-the-loop testbed intended for small satellite applications. The system is composed entirely of commercial off-the-shelf components and integrates both a custom star tracker and a screen-based star field simulator for controlled, repeatable testing. An analytical modeling approach was used in the early design phase to predict system accuracy based on key optical and geometric parameters, informing the selection and configuration of components and guiding the development of calibration routines.

A simulation environment was developed to validate the star tracker software and assess the impact of …

Hardware-In-The-Loop Testing For The Polysim Adcs Lab, Shealyn P. Miller

Master's Theses

Hardware-in-the-loop, HIL, testing is an important tool for the validation and verification of systems in the aerospace industry. A common subsystem to be tested using HIL testing is the attitude, dynamics, and controls subsystem, ADCS. This is due to HIL tests using realistic simulations of the space environment to control physical hardware. To create a HIL test, a simulation and HIL interface are needed to test and communicate with hardware. Using a Speedgoat Performance Real-Time Target Machine to communicate with a Raspberry Pi and a Simulink model, three tests were conducted to ensure communication was functioning properly. A simulation, in …

Identifying Interchromosomal Interactions Using A Graph-Based Computational Pipeline, Ethan Outangoun

Master's Theses

Current computational tools for analyzing chromatin organization are mainly focused on intrachromosomal interactions, despite growing evidence that suggests long-range interactions across chromosomes contribute to transcriptional regulation and disease development. This thesis aims to address this gap in interchromosomal genome analysis, presenting a robust computational pipeline that identifies a clique (i.e., a subgraph) of highly interacting trans-chromosomal regions anchored at a user-specified seed genomic locus. A weighted interaction network is constructed from an input Hi-C contact matrix, a widely used experimental assay for measuring genome-wide chromatin interactions. We model this input contact matrix as a graph and devise three different strategies …

Investigating And Evaluating Poison Unlearning Under Imperfect Detection, Mitashi D. Parikh

Master's Theses

Machine unlearning is an emerging field focused on removing the influence of specific data points from trained machine learning models. Early work in this field has primarily focused on privacy-oriented unlearning, often motivated by data protection regulations such as the GDPR. More recently, security-oriented unlearning has emerged as a response to data poisoning attacks, where malicious inputs are injected into training data to manipulate model behavior. In these security-oriented settings, unlearning methods aim to reverse the influence of malicious training data after a model has already been deployed. However, existing methods assume access to an accurately identified portion of poisoned …

Clusters, Trends, And Choices: Feature Selection In Interactive Statistical Graphics, Dylan Le

Master's Theses

Exploratory data analysis (EDA) is a method for uncovering the structure and key characteristics of data, often through the use of statistical graphics. These visual tools can reveal patterns and trends, and their effectiveness can be enhanced through interactivity. By enabling users to filter data, zoom, and toggle visual features, interactive plots can accelerate and enrich the EDA process. This study extends a previous graphical study by incorporating an interactive framework. Using a statistical lineup protocol with two target patterns (a linear trend and a clustering trend) participants interacted with plots by toggling various aesthetic features, including cluster coloring, ellipses …

The Effect Of Whole Fruits High In Anthocyanins On Markers Of Glycemic Control In Women, Sophia C. Johnson

Master's Theses

Cardiometabolic diseases are a significant health burden worldwide and remain the leading cause of death among adults in the United States. Type 2 diabetes mellitus (T2DM) is a central component of cardiometabolic dysfunction and substantially increases the risk for cardiovascular disease. As women enter the post-menopausal period, significant declines in estrogen levels lead to a heightened risk of T2DM in this population. Observational and experimental evidence has shown potential for fruits high in anthocyanins (ACs) to reduce the risk of T2DM and improve glycemic control. This systematic review and meta-analysis examined the current research on whole fruits high in ACs …

The Chumash War Of 1824: Revolution And Counterrevolution In The California Missions Santa Inés, Santa Barbara, And La Purísima, Joseph V. Payne

Master's Theses

In 1824, the Indigenous Chumash of Missions Santa Inés, Santa Barbara, and La Purísima de Concepción went to war against the settler-colonial system that bonded them to the mission lands and forced labor regime demanded by the Spanish Franciscan missionaries and compelled by Mexican military force in Alta California. The conflict lasted months and included violent battles and skirmishes at all three missions, the militant occupation and reclamation of La Purísima, a mass exodus to the interior of the territory, and the subsequent counterrevolutionary collaboration of the Spanish missionaries and Mexican military to return many (but not all) of the …

Adaptive Volatility Forecasting Models, Jeffrey K. Tan

Master's Theses

In finance, risk is often quantified by volatility, and computing accurate volatility forecasts — while vital to financial decision making — remains one of the most challenging tasks in financial modeling. This thesis, motivated in part by the Black-Scholes-Merton Model and its limitations, adopts a statistical approach to volatility forecasting. The two main models of interest are the Exponential Weighted Moving Average (EWMA) model and the GARCH(1,1) model. Specifically, this work expands upon a potential adaptive lambda algorithm for EWMA models first proposed by Bernard Bollen (2014), and this work also utilizes the Momentum of Predictability (MoP) to generate adaptive …

Ev Microgrid Inspired Open-Source Power Inverter, Bryan A. Carrillo Martinez

Master's Theses

The development of open-source power electronics platforms plays an instrumental role in accelerating microgrid deployment, electric vehicle (EV) integration, and educational access to embedded power electronic converters. This thesis presents the design, implementation, and validation of the Atinverter V2, an open-source DC to AC inverter intended for low power EV microgrid applications and educational settings. The Atinverter V2 integrates various hardware and software subsystems centered around the ATMEGA328P microcontroller, enabling PWM-based sinusoidal power inversion, DC/AC voltage and current sensing, and embedded control features. Software development leverages a C++ object-oriented library and multiple Arduino-based modules to facilitate modular and scalable operation. …

The Degrees Of The Irreducible Representations Of The Symmetric Group With Respect To Primes, Vanessa F. Beeler

Master's Theses

In this thesis, we explore the relationship between the degrees of irreducible matrix representations of the symmetric group and prime numbers. We start by building up the required background necessary to construct our results. We dive into topics of discrete mathematics including matrix representations, characters of representations, integer partitions, conjugacy classes, class functions, and tableaux. Some other key ingredients in our work include using character tables to classify the irreducible rep- resentations of the symmetric group and the hook-length formula to easily compute the degrees of these representations. Once we have laid the groundwork for our in- vestigation, we begin …

Subalpine And Alpine Plant Community Turnover In Yosemite National Park Following 30 Years Of Climate Warming, Rachel Friesen

Master's Theses

Subalpine and alpine regions in California are warming more rapidly than lower elevations. In response, high-elevation plants may acclimate or adapt to the new climate, move to higher elevations or latitudes, persist in refugia, or go extinct. While models predict substantial declines in subalpine and alpine plant communities due to discontinuous population distributions and lack of upslope area, actual responses may vary due to lags in dispersal, establishment, and extinction. Although shifts in high-elevation plant communities have been documented in other regions of the world, such changes have not yet been studied in Yosemite National Park. To assess high-elevation plant …

Assessment Of The Imx7ulp Heterogeneous Soc For Use In A Next Generation Student Cubesat Obc, Lorenzo A. Pedroza

Master's Theses

CubeSats represent a rapidly evolving platform for space research, industry, and education, demanding increasingly sophisticated onboard computing solutions that balance performance, fault tolerance, size, weight, and power constraints. Although the design of the Cal Poly's CubeSat Lab's (PolySat) current On-Board Computer (OBC) keeps up with many of these factors, the demands of modern workloads like fine attitude determination will start to outpace available compute. While the selection of a more capable processor to address this would have traditionally resulted in increased energy usage, modern system-on-chip (SoC) architectures offer novel ways to trade available compute for power savings on-the-fly. With this …

Development Of A Novel Bio-Mimetic Ornithopter With Variable Flapping Angle, Geourg Kivijian

Master's Theses

From the beginnings of flight, flapping-winged flight has been a goal of many engineers to mimic and replicate. With gains in aerodynamic efficiency of flight and certain other favorable characteristics such as reduced noise, higher maneuverability, and surveillance opportunities in urban environments, flapping-wing aerial vehicle(FWAV) designs are consistently pursued in many corners of academia and industry. This thesis goes into the development of a flapping wing aerial vehicle with a Bio-mimetic novel drive mechanism that is cable-driven and can produce variable amplitude and frequency flapping stroke. Employing a Field-Oriented Control (FOC) Brushless Direct Current (BLDC) motor, paired with a bio-mimetic …

A Fault-Tolerant, Multi-Heap Dynamic Memory Allocator For Freertos, Garrett E. O'Neill

Master's Theses

The use of dynamic memory allocation presents a significant challenge for embedded systems, particularly in applications that require high reliability. The software controlling these systems needs to perform critical operations within strict timing constraints, and memory management plays a critical role in a system’s ability to meet these constraints. Dynamic memory allocation is inherently non-deterministic: if a task requests memory, it is impossible to predict how long it will take for the memory to be allocated. If a critical task were to rely on dynamically allocated memory, its execution could become stalled leading to a missed deadline and system failure. …

Leveraging Machine-Learning Algorithms In Two Car Crash Detection Systems On A Custom Dataset, Addison Jacob Sandvik

Master's Theses

Traffic accidents pose a significant threat to public safety, causing millions of deaths and injuries worldwide each year. While efforts to reduce accidents have seen limited progress in recent years, improving emergency response times through automated detection systems is a promising avenue for saving lives. This thesis describes the development of machine learning-based traffic accident detection systems, exploring both video classification and image detection models. The models are trained on a new dataset deemed the Cal Poly Traffic Accident Dataset, an extension of the existing Car Accident Detection and Prediction (CADP) dataset with a precise collision annotations. Two systems were …

Design, Fabrication, And Testing Of A Dual-Rate Spring System For Mountain Bike Frames, Lucas P. Grizzle

Master's Theses

The design of full-suspension mountain bikes is a careful balance of suspension kinematics, structural dynamics, and manufacturing optimization for the expected use case. A bike designed to excel in one area will likely exhibit reduced performance in others. This optimization problem is addressed by designing, integrating, and testing a dual-rate spring system within a fully custom frame. The dual-rate spring is fully decoupled from the rest of the suspension kinematics, providing designers with an additional parameter to achieve ideal suspension behavior. This is accomplished by placing a thermoplastic polyurethane (TPU) bushing in series with the rear shock. The influence of …

Thermal Modeling Techniques For Additively Manufactured Porous Metals, Lucas D. Rambo

Master's Theses

Advances in additive manufacturing have enabled the creation of metallic components with tailored porosity, offering design flexibility for thermal, structural, and fluid transport applications. This thesis investigates the effective thermal conductivity (ETC) of porous Inconel 625 (IN625) and Inconel-ceramic composites (IN625-RAM2) fabricated by Laser Powder Bed Fusion (LPBF) using Elementum 3D’s PermiAM technology. Experimental measurements of thermal conductivity using the laser flash method are compared to numerical models built from micro-computed tomography data. Simulations were performed using both finite element (FE) and finite volume (FV) methods to evaluate thermal transport in real microstructures. The study investigates the effects of micro- …

Density-Dependent Habitat Selection And Home Range Sizes In A Recovering Population Of Island Foxes (Urocyon Littoralis) On Santa Rosa Island, California, Kathleen B. Elder

Master's Theses

Understanding factors that affect how animals select their home ranges is critical for proper species management, especially for threatened and endemic species. Density-dependent factors can be particularly difficult to understand because studying them requires large fluctuations in population size. The island fox (Urocyon littoralis), endemic to the California Channel Islands, has experienced dramatic fluctuations in population size making it an excellent candidate for studying the effects of density on home range size and habitat selection. In 2009, researchers on Santa Rosa Island took advantage of this “natural experiment” to document fox home ranges and habitat selection at a …

From Conflict To Clarity: Resolving Differences In Habitat Assessments To Inform Conservation Priorities For The Giant Kangaroo Rat, Caroline Mackenzie

Master's Theses

From Conflict to Clarity: Resolving Data Differences in Habitat Assessments to Inform Conservation Priorities for the Giant Kangaroo Rat

Caroline MacKenzie

Conservation strategies frequently rely on habitat suitability models, habitat assessments and species occurrence data to identify areas for protection. However, these methods often produce conflicting inference on species presence and habitat quality, complicating management decisions. This study builds on prior work which used three distinct methods to guide conservation planning for the endangered Giant Kangaroo Rat (Dipodomys ingens): habitat suitability modeling based on abiotic predictors, aerial imagery to assess habitat quality through visible burrow mounds and live-trapping …

Multibeam Communication With Digital Sparse Arrays, Tavita Dayton

Master's Theses

The thesis presents a novel approach to maximizing spectral efficiency by utilizing spatial spectrum sharing in digital sparse arrays through non-uniform element configurations. A genetic algorithm approach is developed to optimally place the array elements to achieve maximum beam orthogonality and isolation. The proposed method is compared against three different configurations, namely purely random, random with jitter, and the Van Der Corput sequence (a low-discrepancy sampling approach). Simulated results demonstrate that the genetic algorithm and jitter methods successfully meet design specifications for beam orthogonality, average interelement spacing, and computational time. At the same time, the random and Van Der Corput …

Open Source Asic Design Curriculum, Francisco Wilken

Master's Theses

The ever-growing importance of Application-Specific Integrated Circuits (ASICs) in a high-compute world necessitates that college graduates entering the workforce are well prepared to design them. This thesis details the design of novel ASIC curriculum, using open source tools to teach at the undergraduate level. By moving to a higher level of abstraction than classical transistor-focused coursework, chip design material can be made accessible earlier in an undergraduate degree. Additionally, open source tools provide a powerful, free, and portable platform for students to create their own designs, solving assignments focused on industry readiness. Finally, this thesis studies the results and challenges …

Remote Monitoring And Control Of Protection Relays Via Programmable Logic Controller, Rio Mcgown-Kauffman

Master's Theses

The purpose of this study is to explore the ability of a programmable logic controller (PLC) to wirelessly monitor and control power protection relays. The technologies surrounding power protection and industrial automation are ever evolving and have developed significantly in recent history. Industrial power applications call for consistent condition monitoring and status updates for various high-importance components. The high-importance components have power protection schemes that are managed by digital relays to trip circuit breakers in fault or unsafe operating conditions. The smart relays have a wide range of capabilities, including communications. Cal Poly assembled a collection of relays from Schweitzer …

Birch With Tidyclust In R, Jacob Perez

Master's Theses

This thesis introduces a new implementation of the BIRCH clustering algorithm within the tidyclust framework in R. Traditional hierarchical clustering methods face scalability limitations with large datasets, due to their computational complexity. BIRCH offers a scalable alternative by summarizing data into microclusters using a CF-tree. This work shows the integration of the phases of the BIRCH algorithm into tidyclust, which enables a streamlined workflow for model specification, evaluation, and prediction. Through this implementation, scalable hierarchical clustering has been brought to R users within the tidyclust interface, enhacing the ability to better analyze large datasets.

Hands-Free Balance Protocol And Development Of An Iphone App For Self-Assessment, Jacob Matties

Master's Theses

For many clinical populations, the measurement of balance is a critical task. Previous studies have agreed that smartphone IMUs provide a valid measure of balance that can be significantly correlated with force plate measurements and is sensitive enough to distinguish between various balance poses, but many balance assessment protocols require uncommon equipment or the use of hands during assessment. These limit accessibility of balance assessment. To eliminate the need for hands or any additional equipment, this study assessed the use of a smartphone recording the root mean square of 3D acceleration magnitude. The goal of the study was to determine …

Analyzing Player Difficulty Perception In Platformers Through Procedural Level Generation, Sasank Madineni

Master's Theses

Games utilizing Procedural Level Generation (PLG), such as Roguelikes, are becoming increasingly popular in today's gaming sphere. In games employing PLG, levels are generated randomly or pseudo-randomly, and aim to retain player attention through variance in levels between playthroughs. However, when generating levels with variance in structure and design, player enjoyment is often a mixed bag. With low enjoyment, player retention for these games can dwindle. This study explores the efficacy of real-time difficulty adjustment in procedurally generated platformers, as a method for maintaining stable player enjoyment without causing frustration. This thesis focuses on creating a short user experience, MIMEVA, …

Hybrid Computing For Real-Time Model Predictive Control Of A Buck Converter, Grace Paladichuk

Master's Theses

Advancements in power electronics require high switching frequencies which the digital control routines of the systems cannot keep up with. Analog computing is added to digital control systems to prevent bottlenecks and allow real-time implementation. This paper proposes a hybrid computing model predictive control system for a buck converter. The control system implements the gradient dynamics of the optimization function using digital computing, and the gradient dynamics for the penalty function and integrator using analog computing. For the full simulations of the entire system, the PLECS RT Box is used to simulate the controller in real time with a 1 …