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A Modified Preconditioned Conjugate Gradient Method For Approximating The Scattering Amplitude, Samson Ayo

Master's Theses

In this thesis, we look at an iterative method for approximating the scattering amplitude that involves solving two linear systems: a forward system Ax=b and an adjoint system A^Ty=g. Once these two systems are solved, the scattering amplitude, defined by g^Tx=y^Tb is easily obtained.

We derive a conjugate gradient-like iteration for a nonsymmetric saddle point matrix that is constructed to have a real positive spectrum. We investigate the use of Schur Complement preconditioners with block-diagonal factorization to speed up the convergence of our method and compare …

Assessing The Rates Of Post-Depositional Change Within 2004 Indian Ocean Sediments: Implications For Long-Term Records Of Paleotsunamis, Lillian Pearson

Master's Theses

Foraminifera are commonly used to examine patterns of tsunami inundation occurring over centennial to millennial timescales, but the impacts of post-depositional change on geologic reconstructions are unknown. In Sumatra, the taphonomic character (i.e., test surface condition) of a foraminifer can deteriorate over time, rendering them unidentifiable, and even dissolve them entirely. Here I investigate the rates of post-depositional change of foraminiferal assemblages found within the 2004 Indian Ocean Tsunami (IOT) deposit over a 15-year time interval in Aceh, Indonesia in a vegetated open coastal plain (Site 1: Pulot) and an unvegetated protected coastal cave (Site 2). I identified two zones …

The Effects Of Segmenting Worksheets On Independent Seatwork With Elementary Students Delivered In A Remote Manner Using Parents As Interventionists, Lauren Peak

Master's Theses

Students have a limited amount of time each day to complete independent assignments. These assignments prioritize the learning opportunities provided to students. Learning opportunities or the chance to practice with feedback is highly effective, and additional repetition enhances the learning experience. By increasing student's time-on-task, they will be provided more learning opportunities. This study sought to discover if segmented work could increase the number of problems completed, digits correct per minute and on-task behavior. An alternating treatment design across four participants allowed for the comparison of segmented worksheets and whole worksheets. Additionally, parents served as the interventionist in this remote …

Subadult Cortical Bone Analysis As An Indicator Of Childhood Health Status Among The Tipu Maya Population, Jaime Thomas

Master's Theses

This thesis explores juvenile health at the contact Maya site of Tipu in western Belize. The associated cemetery was excavated and provided a large and well-preserved population. Although Tipu has been a focus of many studies, few studies have focused on subadults and none on their cortical development, which can allow insight into access to necessary nutritional resources.

Some 108 femora belonging to individuals aged birth to 13 years with femora previously sectioned at midshaft provided the sample. External dimensions taken included diaphyseal length, circumference, medial-lateral diameter and anterior-posterior diameter. Additionally, cortical thickness was measured at four points, and 95 …

Stability Of Earth's Trajectory Inside A Binary Star System, Michael Krunic

Master's Theses

The evolution of the solar system is an interesting dynamical problem in celestial mechanics. Computer simulations have shown that planetary bodies in multiple-body systems become unstable after a long time. In this thesis, through numerical simulations, we investigate the stability of the Earth in a binary star system. In the Sun, Earth, and Jupiter three-body system, we treat Jupiter as the second star (Star 2) and we simulate the Earth's orbit over many orbital periods. In our program, we generate the positions, velocities, accelerations, and other orbital elements of each body using Newton's laws of motion. We explore four types …

The Relationship Between Different Forms Of Exercise And Adhd Symptomatology, Matthew A. Reynolds

Master's Theses

Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder associated with executive function deficits as well as negative life outcomes in both childhood and adulthood. Current treatments to reduce symptoms of ADHD include stimulant medications that act as catecholamine agonists. These medications often cause undesirable side effects, to which end better understanding the effects of non- pharmacological treatments on symptoms of ADHD is critical. Research conducted in children suggests that exercise may be an effective tool for symptom reduction. However, the relationship between exercise and ADHD symptoms remains unclear for adults. The aim of this study was to address this …

Deep Reinforcement Learning With Accelerated Reward Function Technique For Robotics Task Planning, Shifabanu Mohammed Rafiq Shaikh

Master's Theses

The objectives of this research are to investigate, design, develop, and implement a DRL-based reward function enhanced robotics technique to achieve ”human-like” operations for a six DoF robot. Technical challenges for robotics applications arise nowadays with a need to achieve human-like intelligence. DRL can formulate human-likeintelligence by maximizing a long-term reward function. However, the design of states, actions, policies, and reward functions having continuous values turns out to be quite tricky. Lastly, to reach a target position, control motion behavior without calculating inverse kinematics, and update state space for actions and policy optimizations are also challenging. Inspired by Google Deepmind’s …

Examination Of Flow Patterns During Droplet Formation And In Venous Valve Mimic Using Μ-Piv, Vignesha Vijayananda

Master's Theses

In this work, particle image velocimetry (PIV) was used for fluid flow visualization in both continuous and segmented-flow microfluidics. Droplet microfluidics is known for its precise and consistent volume dispersion between microliters and picoliters in volume for application ranging from molecular synthesis, drug discover, and diagnostics. But the influence of junction geometry on the process of drop formation has not been investigated. In this study, µ-PIV was used to study the internal flow during the drop formation process in flow-focus microfluidic device with and without constriction. It was found that in case of flow-focus with constriction, the shear force on …

Multi-Robot Path Planning Using Sampling-Based Algorithms And Reinforcement Learning, Donald J. Alexander

Master's Theses

In today’s world, robots are becoming extremely useful in many facets of life. With the recent increase in applicable uses of robots, multi-robot path planning has emerged as a fundamental research area. Multi-robot path planning is the process of developing a coordinated plan which is utilized by multiple robots to efficiently work together to complete a common goal. Over the history of multi-robot path planning, many new path planning methodologies have been developed with the goal of outperforming the last, boasting better efficiency and optimality. In this thesis, an analysis of various multi-robot path planning methodologies is carried out with …

Analysis Of The Slo Bay Microbiome From A Network Perspective, Lien Viet Nguyen

Master's Theses

Microorganisms are key players in the ecosystem functioning. In this thesis, we developed a framework to preprocess raw microbiome data, build a correlation network, and analyze co-occurrence patterns between microbes. We then applied this framework to a marine microbiome dataset. The dataset used in this study comes from a year-long time-series to characterize the microbial communities in our coastal waters off the Cal Poly Pier. In analyzing this dataset, we were able to observe and confirm previously discovered patterns of interactions and generate hypotheses about new patterns. The analysis of co-occurrences between prokaryotic and eukaryotic taxa is relatively novel and …

Modeling Action Potential Propagation During Hypertrophic Cardiomyopathy Through A Three-Dimensional Computational Model, Julia Elizabeth Kelley

Master's Theses

Hypertrophic cardiomyopathy (HCM) is the most common monogenic disorder and the leading cause of sudden arrhythmic death in children and young adults. It is typically asymptomatic and first manifests itself during cardiac arrest, making it a challenge to diagnose in advance. Computational models can explore and reveal underlying molecular mechanisms in cardiac electrophysiology by allowing researchers to alter various parameters such as tissue size or ionic current amplitudes. The goal of this thesis is to develop a computational model in MATLAB and to determine if this model can accurately indicate cases of hypertrophic cardiomyopathy. This goal is achieved by combining …

Minimizing Leakage In Thin Walled Structures Printed Through Selective Laser Melting, Andrew Spencer Yap

Master's Theses

In this project, the scan strategy of selective laser melting (SLM) for thin walled structures was investigated by changing laser parameters and tool path. Producing thin walled structures is difficult due to defects such as warpage and porosity. A layer on the SLM 125 consists of hatch volume, fill contours, and borders, however, for thin walls, hatch volume can become unavailable, resulting in a solely border/fill contour laser tool path.

Three central composite designs (CCD) were created to optimize the laser parameters of borders to minimize leakage rate and porosity. The two factors changed were border laser power and scanning …

Design Of An Automatic Fish Processing Line Using Machine Learning, Sangam Mainali

Master's Theses

This thesis presents an approach to automatic fish processing in the fishing industry using artificial intelligence. Using transfer learning approach (VGG16 model), convolutional neural network (CNN), and image processing, this thesis demonstrates the series of steps from intake of fishes, chopping of head and tail to collecting the body parts of fishes separately thus making it ready for post-processing or direct packaging as per the industrial and consumer needs. To present the idea of the classification of fishes, we have considered five different fishes and one shrimp, altogether six classes. After the classification, the fishes are sorted out according to …

Exploring Material Representations For Sparse Voxel Dags, Steven Pineda

Master's Theses

Ray tracing is a popular technique used in movies and video games to create compelling visuals. Ray traced computer images are increasingly becoming more realistic and almost indistinguishable from real-word images. Due to the complexity of scenes and the desire for high resolution images, ray tracing can become very expensive in terms of computation and memory. To address these concerns, researchers have examined data structures to efficiently store geometric and material information. Sparse voxel octrees (SVOs) and directed acyclic graphs (DAGs) have proven to be successful geometric data structures for reducing memory requirements. Moxel DAGs connect material properties to these …

Modeling And Control Of A Vertical Hopping Robot, Bradley Y. Kwan

Master's Theses

Single degree-of-freedom hopping robots are typically modeled as spring loaded inverted pendulums (SLIPs). This simplified model, however, does not consider the overall leg geometry, consequently making it difficult to investigate the optimized inertial distribution of the leg for agile locomotion. To address this issue, the first part of this thesis establishes an accurate mathematical model of a DC-motor-driven, two-link hopping robot where the motors are modeled as torque sources. The equations of motion for the two distinct phases of locomotion (stance and flight) are derived using the Lagrangian approach for holonomic systems. A Simulink/Stateflow model is developed to numerically simulate …

Modeling Covid-19 Spread Using An Agent-Based Network, Stephen Yh Hung

Master's Theses

Beginning in 2019 and quickly spreading internationally, the Coronavirus disease Covid-19 became the first pandemic that many people have witnessed firsthand along with the severe disruption to their daily lives. A key field of research for Covid-19 that is studied by epidemiologists, biologists, and computer scientists alike is modeling the spread of Covid-19 in order to better predict future outbreaks of the pandemic and evaluate potential strategies to reduce infections, hospitalizations, and deaths.

This thesis proposes a method of modeling Covid-19 spread and interventions for local environments based on different levels of perspective. The goal for this thesis is to …

Monte Carlo Stack-Up Tolerance Analysis Of The Hybrid Rf/Optical Antenna Edge Sensors, Kara Hewson

Master's Theses

The Deep Space Network (DSN), located at the Jet Propulsion Laboratory (JPL), is developing an RF/Optical Hybrid Antenna. This antenna concept will support the reception of high-bandwidth optical deep-space communications with simultaneous support of conventional RF uplink and downlink. The optical system on the antenna consists of sixty-four hexagonal mirrors positioned to form a spherical aperture. To align the mirrors, a Position Opto-Electronic Metrology Sensor (POEMS) system is used to measure the position of each mirror relative to one another. The POEMS system consists of a sender called a collimator, which sends collimated light to the receiving component, called a …

The Effect Of Reaction Conditions On The Nucleation And Particle Growth Of A Colloidal Covalent Organic Framework, Brendan Posson

Master's Theses

Covalent organic frameworks (COFs) are a novel class of crystalline materials with regular porosity, high specific surface area, and various linkage chemistries. Conventional chemical syntheses of these materials lead to the formation of bulk powders characterized as polycrystalline aggregates. Synthesizing these materials as colloidal systems is an effective means to prevent aggregation and achieve larger single-crystalline domain sizes. In this thesis, I describe the effect of temperature and transimination catalyst strength on COF particle nucleation and particle growth. Morphology and crystallinity of the COF-300 particles were confirmed using X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The onset of colloidal …

Development Of A Cubesat Conceptual Design Tool And Implementation Of The Eps Design Module, Sean K. Nogrady

Master's Theses

This thesis is the product of an effort to develop a CubeSat Conceptual Design Tool for the California Polytechnic State University CubeSat Laboratory. Such a tool is necessary due to inefficiencies with the current conceptual design process. It is being developed to increase accessibility, reduce design time, and promote good systems engineering within CubeSat development.

The development of the architecture of a conceptual design tool, the core user-interface element, and the completion of a module for the electrical power subsystem is the focus of this thesis. The architecture is built around different modules to design different subsystems that work in …

Cultivating Creativity In Aerospace Systems Engineering To Manage Complexity, Kenneth Lucas Dodd

Master's Theses

In recent decades, complexity in aerospace programs has been increasing, leading to large budget and schedule overruns. Many of the risks of complex system development can be attributed to the inadequacy of linear methods when applied to nonlinear domains, i.e., oversimplification in a program amplifies the amount of risk produced when a system behaves unexpectedly. Effectively managing complexity involves responding to the various sources of complexity, whether it appears in the objective behavior of the system itself or in the subjective behavior of the people developing it. Thus, the engineering of complex systems requires nonlinear modeling methods of the system …

Investigating Daily Fantasy Baseball: An Approach To Automated Lineup Generation, Ryan Smith

Master's Theses

A recent trend among sports fans along both sides of the letterman jacket is that of Daily Fantasy Sports (DFS). The DFS industry has been under legal scrutiny recently, due to the view that daily sports data is too random to make its prediction skillful. Therefore, a common view is that it constitutes online gambling. This thesis proves that DFS, as it pertains to Baseball, is significantly more predictable than random chance, and thus does not constitute gambling.

We propose a system which generates daily lists of lineups for Fanduel Daily Fantasy Baseball contests. The system consists of two components: …

A Study Of Implementation Methodologies For Distributed Real Time Collaboration, Lauren A. Craft

Master's Theses

Collaboration drives our world and is almost unavoidable in the programming industry. From higher education to the top technological companies, people are working together to drive discovery and innovation. Software engineers must work with their peers to accomplish goals daily in their workplace. When working with others there are a variety of tools to choose from such as Google Docs, Google Colab and Overleaf. Each of the aforementioned collaborative tools utilizes the Operational Transform (OT) technique in order to implement their real time collaboration functionality. Operational transform is the technique seen amongst most if not all major collaborative tools in …

Proving Correctness Of A Chez Scheme Compiler Pass, Ian R. Atol

Master's Theses

We present a proof of correctness for a pass of the Chez Scheme compiler over a subset of the Scheme programming language. To improve trust in our proof approach, we provide two different validation frameworks. The first, created with the Coq proof assistant, is a partial mechanization of the proof, notably implementing a formal semantics for our subset of Scheme. This framework was designed to serve as a basis for the future work of a complete mechanization of our proof. The second framework uses an existing implementation of the Scheme semantics to demonstrate correctness of the pass on a variety …

Selection Of Overwintering Microclimate By Migratory Western Monarch Butterflies, Kiana Saniee

Master's Theses

Migratory species are expected to demonstrate habitat selection that occurs at multiple spatial and temporal scales. Western monarch butterflies migrate seasonally to overwinter in groves at geographically predictable locations along the California coast. To date, overwintering habitat selection by western monarch butterflies has been studied assuming that habitat selection occurs where overwintering aggregations form, meaning at the spatial scale where monarchs form dense overwintering aggregations within overwintering groves. We argue that since western monarch butterflies are migratory, studies of habitat selection could have commingled selection at different scales into a single spatial scale. This likely leads to ignoring some levels …

A Survey Of Computer Graphics Facial Animation Methods: Comparing Traditional Approaches To Machine Learning Methods, Joseph A. Johnson

Master's Theses

Human communications rely on facial expression to denote mood, sentiment, and intent. Realistic facial animation of computer graphic models of human faces can be difficult to achieve as a result of the many details that must be approximated in generating believable facial expressions. Many theoretical approaches have been researched and implemented to create more and more accurate animations that can effectively portray human emotions. Even though many of these approaches are able to generate realistic looking expressions, they typically require a lot of artistic intervention to achieve a believable result. To reduce the intervention needed to create realistic facial animation, …

Design Of A Three-Phase Brushless Dc Motor Control System, Peyton Ulrich

Master's Theses

In the past several decades, the Brushless DC (BLDC) motor has seen increased usage due to several distinct advantages over its brushed counterpart, including higher performance, increased reliability, and minimal maintenance requirements. However, the electronic commutation system of the BLDC motor creates the need for an accompanying electronic motor control system of increased complexity, adding to the overall cost of the BLDC motor and motor control system. As such, continued research and exploration in the area of BLDC motor control is necessary to continue to reduce the cost of BLDC motors and their corresponding motor control systems. This project focuses …

Simulation Of A Configurable Hybrid Aircraft, Brandon Bartlett

Master's Theses

As the demand for air transportation is projected to increase, the environmental impacts produced by air travel will also increase. In order to counter the environmental impacts while also meeting the demand for air travel, there are goals and research initiatives that aim to develop more efficient aircraft. An emerging technology that supports these goals is the application of hybrid propulsion to aircraft, but there is a challenge in effectively exploring the performance of hybrid aircraft due to the time and money required for safe flight testing and due to the diverse design space of hybrid architectures and components. Therefore, …

Real-Time Stylized Rendering For Large-Scale 3d Scenes, Jack Pietrok

Master's Theses

While modern digital entertainment has seen a major shift toward photorealism in animation, there is still significant demand for stylized rendering tools. Stylized, or non-photorealistic rendering (NPR), applications generally sacrifice physical accuracy for artistic or functional visual output. Oftentimes, NPR applications focus on extracting specific features from a 3D environment and highlighting them in a unique manner. One application of interest involves recreating 2D hand-drawn art styles in a 3D-modeled environment. This task poses challenges in the form of spatial coherence, feature extraction, and stroke line rendering. Previous research on this topic has also struggled to overcome specific performance bottlenecks, …

Solving Chromatic Number With Quantum Search And Quantum Counting, David Lutze

Master's Theses

This thesis presents a novel quantum algorithm that solves the Chromatic Number problem. Complexity analysis of this algorithm revealed a run time of O(2^n/2n²(log2n)²). This is an improvement over the best known algorithm, with a run time of 2ⁿn^O(1) [1]. This algorithm uses the Quantum Search algorithm (often called Grover's Algorithm), and the Quantum Counting algorithm. Chromatic Number is an example of an NP-Hard problem, which suggests that other NP-Hard problems can also benefit from a speed-up provided by quantum technology. This has wide implications as many real world problems can …

Groundwater Model Studying Effects Of Existing Recharge Basin And Proposed Subsurface Barrier For A Ranch In Santa Rosa Creek Watershed, Stefan J. Young

Master's Theses

A groundwater model of a 126.2-acre ranch in Cambria, California was expanded upon to analyze the effects of artificial recharge and a subsurface barrier. The ranch lies within the 48mi² Santa Rosa Creek Watershed along the Central Coast of California. The mainly agricultural watershed outfalls to the Pacific Ocean to its west. Creek Lands Conservation, a non-profit that aims to conserve and restore habitat along the Central Coast, plans to identify projects to restore stream flow during dry seasons in the creek that runs through the Santa Rosa Creek Watershed and to increase artificial groundwater recharge. This study focuses …