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The Effects Of A Baseball Season On Various Body Composition Measurements And Assessment Of Dietary Intake In Ncaa Di Baseball Players, Jordan Marthens

Master's Theses

Despite the known importance of body composition in relation to performance and health of athletes, this study appears to be the first, or one of very few, to evaluate body composition measures from the beginning to end of season for NCAA DI collegiate baseball players and assess their dietary intake. Baseball players from the 2015-2019 seasons were included in the study (n=78; age=19.8±1.28). DXA scans performed at the start and end of season were analyzed and 3-day food records analyzed via ESHA software were utilized to assess dietary intake. Groups were stratified to examine differences in players’ positions (Pitchers vs. …

Smartphone-Tape Method For Calculating Body Segment Inertial Parameters For Analysis Of Pitching Arm Kinetics, Jay Sterner

Master's Theses

The objectives of this study were to (1) develop a non-invasive method (referred to as Smart Photo-Tape) to calculate participant-specific upper arm, forearm, and hand segment inertial properties (SIPs) (e.g. mass, center of mass, and radii of gyration) and (2) use those Smart Photo-Tape properties in inverse dynamics (ID) analyses to calculate injury-related pitching arm kinetics. Five 20- to 23- year-old baseball pitchers were photographed holding a baseball and analyzed using the Smart Photo-Tape method to obtain 3-D inertial properties for their upper arm, forearm, and hand. The upper arm and forearm segments were modelled as stacked elliptic cylinders and …

A Parametric Study Of Formation Flight Of A Wing Based On Prandtl's Bell-Shaped Lift Distribution, Kyle S. Lukacovic

Master's Theses

The bell-shaped lift distribution (BSLD) wing design methodology advanced by Ludwig Prandtl in 1932 was proposed as providing the minimum induced drag. This study used this method as the basis to analyze its characteristics in two wing formation flight. Of specific interest are the potential efficiency savings and the optimal positioning for formation flight. Additional comparison is made between BSLD wings and bird flight in formation.

This study utilized Computational Flow Dynamics (CFD) simulations on a geometric modeling of a BSLD wing, the Prandtl-D glider. The results were validated by modified equations published by Prandtl, by CFD modeling published by …

Fast Chirped Signals For A Tdma Ultrasonic Indoor Positioning System, Lauren M. Williams

Master's Theses

In this paper, a new concept for ultrasonic indoor positioning based on instantaneous frequency of ultrasonic signals is presented. Nonlinear phase characteristics of ultrasonic transducers introduce a frequency deviation in ultrasonic signals. By sweeping at very fast rates, a large spike in the deviation is introduced. The artefacts observable in instantaneous frequency estimations are highly localized and present an opportunity for accurate frequency detection. In order to be useful, the artefacts need to take place within the pulse and have sufficient magnitude for accurate processing. The system consists of a transducer transmitter and receiver pair, which have a center frequency …

Writing For Each Other: Dynamic Quest Generation Using In Session Player Behaviors In Mmorpg, Sean Christopher Mendonca

Master's Theses

Role-playing games (RPGs) rely on interesting and varied experiences to maintain player attention. These experiences are often provided through quests, which give players tasks that are used to advance stories or events unfolding in the game. Traditional quests in video games require very specific conditions to be met, and for participating members to advance them by carrying out pre-defined actions. These types of quests are generated with perfect knowledge of the game world and are able to force desired behaviors out of the relevant non-player characters (NPCs). This becomes a major issue in massive multiplayer online (MMO) when other players …

Initial Orbit Determination Error Analysis Of Low-Earth Orbit Rocket Body Debris And Feasibility Study For Debris Cataloguing From One Optical Facility, Kyle Stoker

Master's Theses

This paper is predicated on determining the effectiveness of angles-only initial orbit determination (IOD) methods when limited observational data is available for low-Earth orbit (LEO) rocket body debris. The analysis will be conducted with data obtained from Lockheed Martin Space’s Space Object Tracking (SpOT) facility, focusing on their observational data from 2018 that contains tracking of rocket body debris for less than one minute per overhead pass. After the IOD accuracies are better understood, a feasibility study will follow that investigates the possibility of cataloguing LEO orbital debris from a single optical observation facility with similar observational capabilities as that …

Design Of A Custom Wrist Brace That Can Be 3d Printed From A Three-Dimensional Scan, James D. Baldwin

Master's Theses

Current arm bracing and casting methods for distal forearm and wrist fractures can lead to varying negative medicinal affects such as tightness, skin breakdown and bacteria growth which can cause infection. This can be alleviated by a flexibly compliant and breathable design while keeping the arm and hand fixed at the wrist to promote proper wrist and forearm fracture healing. There have been attempts made to create a 3D printable brace from a three-dimensional scan but they do not account for full encapsulation of the wrist, removability without breaking the brace, nor for the brace being too tight and leading …

Analysis Of Biofilm Remediation Capacity For Octenyl Succinic Anhydride (Osa), A Bioactive Food Starch Modifier Compound, Matthew R. Borglin

Master's Theses

Matthew R. Borglin

This thesis demonstrates efficacy of Octenyl Succinic Anhydride (OSA), as a biofilm sanitizer. Biofilms allow bacteria to adhere to solid surfaces with the use of excreted polymeric compounds. For example, surfaces found in food production or processing facilities such as the interior of a raw milk holding tank, are some of the most susceptible to biofilm contamination. When present, biofilms can cause a variety of negative effects, which include; reduction of product shelf life, corrosion, and outbreaks of foodborne illnesses. The close association of biofilms with the majority of foodborne illness cases led the US Environmental Protection …

Simulating Particle Packing During Powder Spreading For Selective Laser Melted Additive Manufacturing Using The Discrete Element Method In Abaqus, Priscilla Ng

Master's Theses

Metal additive manufacturing allows for the rapid production of complex parts that are otherwise impractical using conventional subtractive manufacturing techniques. Applications for additive manufacturing span across a broad array of industries including aerospace, automotive, and medical, among many others. One metric of printing success is material properties, including part density. While there has been extensive research completed for the density of printed parts, there is little published work concerning powder packing density on the build plate associated with powder spreading.

In this thesis, a Discrete Element Method (DEM) model was created in Abaqus to simulate the spreading behavior of particles …

Attacking Computer Vision Models Using Occlusion Analysis To Create Physically Robust Adversarial Images, Jacobsen Loh

Master's Theses

Self-driving cars rely on their sense of sight to function effectively in chaotic and uncontrolled environments. Thanks to recent developments in computer vision, specifically convolutional neural networks, autonomous vehicles have developed the ability to see at or above human-level capabilities, which in turn has allowed for rapid advances in self-driving cars. Unfortunately, much like humans being confused by simple optical illusions, convolutional neural networks are susceptible to simple adversarial inputs. As there is no overlap between the optical illusions that fool humans and the adversarial examples that threaten convolutional neural networks, little is understood as to why these adversarial examples …

Pocket Rocket: A 1u+ Propulsion System Design To Enhance Cubesat Capabilities, James M. Harper

Master's Theses

The research presented provides an overview of a 1U+ form factor propulsion system design developed for the Cal Poly CubeSat Laboratory (CPCL). This design utilizes a Radiofrequency Electrothermal Thruster (RFET) called Pocket Rocket that can generate 9.30 m/s of delta-V with argon, and 20.2 ± 3 m/s of delta-V with xenon. Due to the demand for advanced mission capabilities in the CubeSat form factor, a need for micro-propulsion systems that can generate between 1 – 1500 m/s of delta-V are necessary.

By 2019, Pocket Rocket had been developed to a Technology Readiness Level (TRL) of 5 and ground tested in …

Host Plant Resistance In Strawberries To Anthracnose And Colonization Of Crown And Root Tissue By Verticillium Dahliae And Macrophomina Phaseolina, Omar A. Gonzalez-Benitez

Master's Theses

Strawberries are considered an important crop in California where in 2018 it was in the top 5 valued fruit and vegetable commodities valued at $2.84 billion accounting for 88% of the total U.S. production. Strawberry production can be severely impacted by soilborne pathogens that can affect strawberry roots, crowns and leaves which can result in plant mortality. As much as 50 to 60% mortality can occur in one field. Pathogens responsible for such losses include Colletotrichum acutatum (syn.C. nymphaeae), Macrophomina phaseolina and Verticillium dahliae. With the phaseout of methyl bromide, host resistance and an understanding of host-pathogen interactions …

The Strawberry Rhizosphere Microbiome: Role On Plant Health And Nutrition, Eric Michael Boyd

Master's Theses

Microbial-root associations are important to help plants cope with abiotic and biotic stressors. Managing these interactions offers an opportunity for improving the efficiency and sustainability of agricultural production. By characterizing the bacterial and archaeal community (via 16S rRNA sequencing) associated with the bulk and rhizosphere soil of sixteen strawberry cultivars in two controlled field studies, we explored the relationships between the soil microbiome and plant resistance to two soilborne fungal pathogens of strawberry (Verticillium dahliae and Macrophomina phaseolina). Overall, the plants had a distinctive rhizosphere microbiome relative to the bulk soil, with higher abundances of known beneficial bacteria …

Quantitative And Qualitative Error Re-Analysis Of Tidal Datasets, Ernesto Andrew Ledezma

Master's Theses

Tidal data forms the basis for understanding and quantifying sea-level rise and tidal statistics. While quality assurance methods based upon spectral and harmonic analysis have been applied to individual tidal records, these methods have not been used to assess global tidal datasets. In this thesis, four west coast tidal records were examined using harmonic analysis methods to investigate uncertainty on a monthly averaged basis. Uncertainty was identified using a method that quantifies time lag as a linear regression of height difference between a predicted and measured tidal height and the predicted rate of change of tidal height. Errors identified through …

Mindfulness For Stress Reduction: Qualitative Analysis Of Perceptions From College Students And Mindfulness Instructors, Beth Marie Merlo

Master's Theses

Although mindfulness interventions with college students have yield positive results, many students are not continuing to engage after the interventions. This may be because very little research has been done to investigate the health behavior beliefs of college students in regard to mindfulness for stress reduction. The purpose of this investigation was to identify the most influential components of the Integrated Behavioral Model (IBM) that potentially assist with predicting college student participation in mindfulness activities for stress reduction. Interviews, informed by the IBM, were conducted with 20 current college students and 5 current mindfulness instructors working with college students. The …

Analysis And Optimization Of Colorimetric Nanosensors For Rapid Detection Of Microbes In Water, Ruby A. Lang

Master's Theses

Access to safe water is a basic human right recognized by the United Nations General Assembly in 2010 (WHO, 2020). However, a least 2.2 billion people globally still are without safely managed water services meaning they use a drinking water source that can be contaminated with faeces (WHO, 2020). With such a pressing global health issue, it is clear that improvement to water systems is important and required in the Agenda 2030 Sustainable Development Goals (SDGs). However, to improve water systems and prove they are safe water sources, water quality testing must occur. A solution to this issue is the …

Altering An Epoxy-Amine Thermoset's Performance Through Varying Mix Ratios, Kiersten M. Smith

Master's Theses

Epoxy resins are used in a number of different industries and therefore have application-specific material requirements, from satellites that require materials that operate in space, to paints and coatings that require high scratch resistance and mechanical durability, to medical devices, designed to be in continuous contact with biological fluids. Commercial epoxy products come with manufacturer’s information explaining the epoxy properties and recommended preparation processing conditions, which may include epoxy resin to curing agent mix ratio (Part A : Part B), cure time, and cure temperature, for example. Due to proprietary reasons, it can be difficult to understand why these values …

Pier Portal, Alec W. Hardy

Master's Theses

The Pier Portal marine monitoring system is an internet controlled underwater camera that will enable students, researchers, and the general public the ability to monitor underwater marine life and ocean conditions. Installed at Cal Poly’s Center for Coastal Marine Science pier at Avila Beach, California, the camera can be commanded in real-time to raise or lower to any position between the top of the pier and the bottom of the ocean floor, while providing a live-stream video to the operator and general public. This thesis effort focused on the integration of the various subsystem components through software, and the development …

Analysis And Design Of An Off-Grid Residential Power System, Christopher Rotsios

Master's Theses

This thesis aims to provide a recommended power system design for optimal efficiency, reliability, and cost in off-grid applications. The power system examined in this project is a residence in an off-grid community called Quail Springs that generates its energy from roof mounted solar panels. The existing system was analyzed to see what equipment can remain, what needs to be upsized, and what needs to be added to the system. Two power systems are considered for the residence: a fully AC power system and a hybrid AC/DC power system. Simulations were run in PSCAD to compare the efficiencies of the …

Supporting Our Troops In Higher Education: Veteran Admissions Training Program, Steven Delgado

Master's Theses

An overview of a Veteran Admissions Training Manual for a California State University campus.

The Practice Of Cantus Planus Binatim As Reflected In John Plousiadenos's Pro-Union Communion Hymns, Simeon Brown

Master's Theses

No abstract provided.

A Code Reputation System Using Ai And Blockchain Technology, Jeremy Chau

Master's Theses

Open source development is a method of development in which source code is developed using the combined skills of the public. A few examples of this sort of development would be the Chromium and Linux kernel projects hosted on GitHub. Open source development offers a wide variety of benefits and disadvantages. A main concern is when many people blindly trust developers without second thought. There is a lack of a rating system that judges those who develop code through open source means. This can call into question the quality of the code being written by the individual as well as …

Life Between The Bridges: A Personal History Of San Francisco, Eli Hansen

Master's Theses

Life Between the Bridges: A Personal History of San Francisco is a hybrid work of history, memoir, and travel writing in which I seek to examine the city of San Francisco through a variety of lenses. The prologue provides an overview of experiences a newcomer to San Francisco might expect. The first chapter examines the current state of the city and addresses the pressing issue of high housing costs. This chapter also introduces the theme of optimism, a unifying concept throughout my thesis. I then provide a brief biography of my childhood and outline the events that led me to …

Understory Response To Restorative Thinning In Coast Redwood Forests, Alyssa Hanover

Master's Theses

Restoration of late seral features in second-growth Sequoia sempervirens forests is an important management concern, as so little of the original old-growth remains. The abundance of herbaceous species provides a metric for assessing recovery in these forests where associated understory plants are adapted to closed canopy conditions. Data were collected using a stratified random sampling design across three treatments: mechanically thinned second-growth, un-thinned second-growth, and old-growth reference stands. Pairwise PerMANOVA indicated greater abundance and diversity of native herbs in old-growth and un-thinned second-growth compared to thinned stands, as well as higher measures of canopy cover, basal area, and dominance of …

The Moderating Effects Of Gender And Occupation On Age Discrimination In Hiring, Rachel Su Windsor

Master's Theses

Over the years, ageism in the workplace has become an important topic. However, it remains unclear whether and how gender and occupation relate to age discrimination in hiring decisions. The current study addresses this issue by investigating job suitability ratings and selection decisions by comparing two hypothetical job applicants who differ in age (younger vs. older) and gender (male vs. female) for two occupations (software engineer vs. nurse) in two industries (high-tech and healthcare). This study employed a 2 x 2 x 2 incomplete mixed-factorial design, in which age was a within-subjects factor, and gender and occupation were between-subjects factors. …

The Baroque In Games: A Case Study Of Remediation, Stephanie Elaine Thornton

Master's Theses

This thesis presents a case study for the remediation of baroque painting by some contemporary video games. Video games such as Horizon Zero Dawn borrow illusionistic techniques, the motif of the labyrinth, and the use of the total work of art as presented in certain baroque paintings. These characteristics are modified and represented within the new medium in an effort to heighten immediacy and create an immersive experience for the audience. This thesis discusses the process of remediation in detail and then analyzes how video games—and Horizon Zero Dawn in particular—remediate illusionistic techniques like linear and atmospheric perspective. Then, the …

Methods For Sensitive Detection Of Magneto Optic Kerr Effect, James Creed

Master's Theses

The focus of this project is to numerically model the phenomenon known as the Magneto Optic Kerr Effect, MOKE, where the interaction between light and surface in the presence of a magnetic field, results in a rotation of the polarization axis of the reflected light, and to develop a method by which to experimentally measure the strength of the interaction. The amount of polarization rotation is proportional to the strength of the magnetic field and changes in polarization can be detected using polarizing optics. This thesis project successfully develops a numerical model for MOKE and an experimental method is outlined …

An Examination Of Garden-Based Education Impacts On Title 1 Elementary School Students’ Environmental Literacy In San José, California, Alexandra Dahl

Master's Theses

The objective of this research was to assess garden-based pedagogy as an effective strategy to increase environmental literacy in elementary-aged students. With severe environmental issues facing children today and into the future, environmental literacy is a desired outcome of environmental education programs. Such interventions create environmentally responsible citizens who understand how humans impact the natural environment and thereby act sustainably. Currently, little research exists on garden education’s influence on students’ environmental literacy, especially in underrepresented communities. Using a nonequivalent control group study design, this project investigated the impact of a garden education program in Central San José, CA in an …

Noise Pollution, Environmental Justice, And Urban Green Space Accessibility: A Case Study In San José, California, Lauryn Duoto

Master's Theses

Noise pollution is an environmental stressor associated with a number of poor health outcomes. Promisingly, recent studies have identified urban green spaces such as public parks and community gardens as-built environments that can minimize noise pollution in the urban context. The objective of this project was to identify low-income communities of color that lack urban green space accessibility within the city of San José, California, to determine if sound level could be an indicator of urban green space usage and to evaluate whether urban green space can mitigate noise. Neighborhood demographics based on census tract data, including ethnicity and socioeconomic …

Auto-Landing System For Fixed-Wing Unmanned Aerial Vehicle, Dan Dermer

Master's Theses

Unmanned aerial vehicle systems, or any kind or autonomous system, are relevant to many applications today. However, they are complex and sophisticated systems that require a deep understanding of multiple technologies. In addition, the mathematical rigor, computer modelling, and programming applications involved make t¬his a challenging field of study. This thesis explores the possibility of achieving the automated landing of a fixed-wing unmanned aerial vehicle. Auto-landing systems can resolve the challenges for the novice user and make aerial vehicle platforms accessible and dependable. A wide spectrum of applications such as agriculture, aerial photography, and security, to name a few, can …