Digital Commons Network^™

Effect Of Polymer Design And Coating Formulation On The Water Uptake And Sensitivity Of Acrylic Water-Borne Films, William Z. Thompson

Master's Theses

Water-borne latex coatings represent a safer, more user-friendly, and environmentally responsible alternative to solvent-borne coatings, and are growing in popularity each year. However, these coatings often exhibit unfavorable performance when exposed to water for extended periods of time. This prolonged exposure often results in water uptake, which may give rise to other detrimental effects such as a decrease in modulus, blushing or water-whitening, reduced serviceable life, and softening of the film. In this study, various polymer composition latex design spaces are studied to develop an understanding of how water uptake can be modulated and minimized using common synthetic approaches. Factors …

Estimating Evapotranspiration Of A Riparian Forest Using Sap Flow Measurements, James R. Solum

Master's Theses

To close the water use budget of irrigated agricultural fields in floodplains with substantial riparian corridors, it is necessary to understand groundwater usage by dominant phreatophytic vegetation, particularly when the primary source of water for irrigation comes from groundwater abstraction. We report here results of estimated evapotranspiration (ET) of a riparian forest, which were based on measurements of sap flow in phreatophytic vegetation within a riparian corridor. The riparian corridor was within a study area 75 to 140 meters wide in the lower portion of the Scotts Creek watershed, which is bounded to the west by the Pacific Ocean in …

Review Of Mentoring Manuals In Stem To Improve The Mentorship Experience For Underrepresented Minority Students Through The Lens Of Social Capital And Combating Social Reproduction, Leno Kurimoto

Master's Theses

There is a lack of diversity and inclusion in STEM (science, technology, engineering, and mathematics) education. Students who pursue a degree in STEM, only less than half of them complete them. However, this phenomenon occurs at a greater percentage for underrepresented minority students (UMS). To combat the lack of representation in STEM, mentoring has been suggested to promote retention and minimize attrition. Mentoring provide plenty of benefits for students, as they can gain academic and professional experience. Unfortunately, mentorship of UMS is not the same compared to Asian and white students, thus different approaches and recommendations must be implemented to …

Determination Of A Graph's Chromatic Number For Part Consolidation In Axiomatic Design, Jeffery Anthony Cavallaro

Master's Theses

Mechanical engineering design practices are increasingly moving towards a framework called axiomatic design (AD). A key tenet of AD is to decrease the information content of a design in order to increase the chance of manufacturing success. An important way to decrease information content is to fulfill multiple functional requirements (FRs) by a single part: a process known as part consolidation. One possible method for determining the minimum number of required parts is to represent a design by a graph, where the vertices are the FRs and the edges represent the need to separate their endpoint FRs into separate parts. …

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 …

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 …

The Mediating Role Of Work Engagement On The Relationship Between Perceived Supervisor Support And Turnover Intention, Addison Yeosock

Master's Theses

The purpose of the current study was to examine the mediating role of work engagement on the relationship between perceived supervisor support and turnover intention using the Jobs Demands-Resources (JD-R) model and the motivational processes of engagement as the theoretical framework. A total of 954 employees of a healthcare organization participated in an online survey. Results showed that work engagement partially mediated the relationship between perceived supervisor support and turnover intention. Perceived supervisor support was negatively related to turnover intention directly and indirectly through work engagement. Based on these findings, organizations should focus on strategies of increasing the job resource …

A Leadership Change. A Culture Shift...And A Police Riot: The Story Of How The Highest College Going High School In San Francisco Became The Lowest Graduating School In The District, Emmanuel Padilla

Master's Theses

Thurgood Marshall Academic High School, located in San Francisco’s Bayview, Hunters Point, scored the third lowest in the most recent Academic Performance Index (API) Report. Based on the median household income, the Bayview is a low-income community and according to San Francisco data, is a high crime neighborhood. The odds are against Marshall to provide exceptional service to their students, but it once did. In 2001, Marshall had the highest college-going rate in the San Francisco Unified School District (SFUSD). Today, only 20% of its student body would be considered college ready. This study will look into what happened to …

Dealing With Faulty Data Via A Physics-Based Filtering Method, Ross Pellenberg

Master's Theses

Gas turbines are expensive, revenue generating machines and, as such, there is a strong interest in practicing state-of-the-art maintenance techniques to keep them running at healthy performance levels. One way to monitor and evaluate gas turbine health is to train a machine learning model on historical run-to-failure sensor data to differentiate between healthy and unhealthy performance. The biggest barrier to building these models is the scarcity of run-to-failure data. Not only is this data expensive and time consuming to acquire, but the data is often not publicly released for competitive purposes. This thesis uses a publicly available run-to-failure dataset previously …

Associations Of Cardiovascular Health, Strength, And Physical Activity In Participants With A History Of Anterior Cruciate Ligament Reconstruction, Kirsten Allen

Master's Theses

No abstract provided.

Innovation Dynamics Of Cultural Production: Evidence In Rap Lyrics, James M. Zumel Dumlao, Junjie Lei, Emeka Nwosu, Li Yu Oon, Tsai Ling Jeffrey Wong, James Rising, Jesse Anttila-Hughes

Master's Theses

Culture is a driving force in organizing the structure of societies, and is conjoined with economic development. However, quantifying the impact of culture is difficult. Culture manifests itself in cultural production, through art, performance, music, etc. Innovation and influence in cultural production industries partially determines product quality. Using techniques from the “digitized humanities”, we agnostically identify informational distance to describe the spatiotemporal dynamics of innovation and influence in Rap music lyrics. Rap emphasizes lyricism and hometown pride more than other genres of popular music, and is interesting as a globally impactful manifestation of the racially segregated labor market in the …

Non-Pll Direct Power Control For A Single-Phase Grid-Connected Three-Level Inverter, King Ademola Adebo

Master's Theses

The growing demand for clean, reliable renewable energy generation has led to the widespread adoption of solar energy as a source of electricity. Technological advancement aiding to reduce the cost of solar photovoltaic (PV) panels, as well as improvement in power electronics and control strategies for solar PV systems have also contributed to the growing popularity. For grid-connected solar systems to adequately meet future demand and grid requirements, the system must be reliable, and not affected by instability or distortions on the power grid.

In this thesis, a control strategy for single-phase grid-connected inverters that can synchronize to the grid …

Computer Vision For Inventory Management, Christopher Bradley Kalahiki

Master's Theses

Deep learning is a subset of machine learning that extracts high-level features from raw data over multiple layers. Deep learning for computer vision has become more popular in the last few years, but the data and resource requirements make it difficult to implement on Internet of Things (IoT) devices. This work aims at providing a series of techniques that can alleviate some of the strain caused by these requirements in order to make a computer vision system for inventory management more feasible. These techniques include data collection, data preprocessing, transfer learning, and a method for intelligently growing a dataset throughout …

Thiol-Ene Click Chemistry For Solid State Triplet-Triplet Annihilation Upconversion And Parts-Per-Billion Pyrophosphate Sensing In Artificial Seawater, Abagail K. Williams

Master's Theses

Thiol-ene click chemistry is a robust approach to molecularly engineering polymers for many applications. Within this work, thiol-ene click chemistry is used to fabricate thiol-ene networks for TTA-UC and to synthesize a conjugated polyelectrolyte (CPE) used as a pyrophosphate (PPi) sensor in complex aqueous media. Chapter I focuses on the synthesis and upconversion performance of rubbery networks fabricated using thiol-ene click photopolymerization. The advancement of triplet-triplet annihilation based upconversion (TTA-UC) in emerging technologies necessitates the development of solid-state systems that are readily accessible and broadly applicable. We demonstrate that thiol-ene click chemistry can be used as a facile cure-on-demand synthetic …

Zebrafish Eye Development: Rac And The Creepy Crawlers Of The Eye, Zvi Murry

Master's Theses

During vertebrate eye development the optic vesicles protrude from either side of the brain and form the optic cups. As an optic cup starts to surround the lens a groove on the ventral side of the eye forms, known as the choroid fissure (CF). Normally, the CF will close around the optic nerve and hyaloid vasculature. If this process does not occur properly it results in a keyhole opening in the eye known as coloboma. This results in blindness and affects nearly 1 in 4-5,000 births. Zebrafish were utilized as a model for eye development to study CF closure (CFC) …

Pismo Clams (Tivela Stultorum) In Califorina: Population Status, Habitat Associations, Reproduction, And Growth, Alexandria R. Marquardt

Master's Theses

Marine shellfish play a vital role in intertidal ecosystems and coastal communities, but many of these fisheries are small-scale and lack the necessary monitoring to ensure long-term sustainability. Effective management often requires information on key demographic parameters, such as population status, reproduction and growth. Pismo clams (Tivela stultorum) are a culturally important and iconic species in California, which supported a thriving commercial and recreational fishery throughout much of the 1900’s. However, Pismo clam populations have declined statewide in recent decades and are attributed to human harvest and predation by California sea otters (Enhydra lutris); However, no …

Sustainable Wastewater Treatment In The American South, Caroline Miles

Master's Theses

Aging infrastructure and changing social and environmental conditions are two factors that are currently pushing wastewater treatment towards more sustainable methods. This thesis investigates what sustainable treatment technologies are being used in the American South through a focused sample of six cities across the region: Austin, Texas; Fayetteville, Arkansas; Hattiesburg, Mississippi; Memphis, Tennessee; Ocean Springs, Mississippi; and Tuscaloosa, Alabama. The study assesses the types of sustainable treatment technology utilized at each facility, the perspectives of wastewater professionals about the technology, and the economic and environmental sustainability of each facility. Data was collected through direct observations on tours of the facilities, …

Homotopy Analysis Method For Nonlinear Ordinary Eigenvalue Problems, Subagya Perera

Master's Theses

In this thesis, we solve nonlinear differential equations by the homotopy analysis method (HAM), which is a semi-analytic method first introduced by Shijun Liao in 1992. The modified HAM can be viewed as a more generalized method that encloses many perturbation and non-perturbation methods. It is different from perturbation or other analytical methods in that it allows considerable freedomformanyvariables. Using the modified HAM, especially zero-order and higher-order deformation equations, we solve a nonlinear initial value problem and a nonlinear eigenvalue problem. We adjust the convergence region of a solution by modifying auxiliary parameter values. The results converge in very few …

An Analysis Of Dredge Efficiency For Surfclam And Ocean Quahog Commercial Dredges, Leanne Poussard

Master's Theses

Between 1997 and 2011, The National Marine Fisheries Service conducted 50 depletion experiments to estimate survey gear efficiency and stock density for Atlantic surfclam (Spisula solidissima) and ocean quahog (Arctica islandica) populations using commercial hydraulic dredges. The Patch Model was formulated to estimate gear efficiency and organism density from the data. The range of efficiencies estimated is substantial, leading to uncertainty in the application of these estimates in stock assessment. Analysis of depletion experiment simulations showed that uncertainty in the estimates of gear efficiency from depletion experiments was reduced by higher numbers of dredge tows per experiment, more tow overlap …

Nearshore Sedimentology Of Eroding Microtidal Estuaries: Bon Secour Bay, Alabama And Perdido Bay, Florida, Jennifer Simpson

Master's Theses

Estuarine shorelines along the northern Gulf of Mexico are dynamic geologic settings that provide numerous ecological and economic benefits. By definition, estuaries are semi-enclosed bodies of water that receive sediment from two sources: (1) fluvial systems feeding into the estuary and (2) sediment transported by wave action and tidal currents from adjacent marine sources. Erosion of estuarine shorelines resulting from rising sea level, storm impact, and anthropogenic influence has been increasingly evident in the microtidal Gulf Coast over recent decades. This study collects quantitative and qualitative data to better understand sedimentary dynamics associated with contemporary estuarine shoreline erosion in Bon …

Using Modern Portfolio Theory To Analyze Virgil's Aeneid (Or Any Other Poem), David Patterson

Master's Theses

This paper demonstrates that it is possible to use mathematics to study literature as it has been used to study the social sciences. By focusing on mathematically defining economic and literary terms, it can be shown that the underlying mathematical structure behind key concepts in economics and literature are analogous. This opens the possibility of applying economic models in literature. Specifically, it is demonstrated that the economic mathematical model of modern portfolio theory can answer long standing questions around the Roman epic Aeneid by Virgil. The poet died before completing his poem. The relative completeness of the books of the …

Investigation On The Morphology Of Charge-Transfer Complexes In Low Density Polyethylene, Wade Korf

Master's Theses

Fillers are used ubiquitously throughout the fields of polymer and material science to overcome many inherent limitations to polymeric materials (i.e. poor stiffness or strength) and to expand their potential applications. There is a need to develop controllable particle architectures to better understand fundamental structure-property relationships in particle reinforced polymer composites. Charge-transfer complexes (CTCs) can assemble in situ into various needle and dendritic shapes via simple fabrication processes and at low loading levels. In this study, the effect of tetrathiafulvalene (TTF) and 7,7,8,8-tetracyanoquinodimethane (TCNQ) CTC crystallites of various shapes and sizes on composite mechanical properties was investigated in an LDPE …

The Development And Evaluation Of A New Analytical Model For The Characterization Of Friction Induced Disc Brake Vibration, Michael Vladimirov

Master's Theses

This research proposes a new method of modeling vibration of disc brake systems. This modeling method treats the brake pads of a disc braking system as lumped spring-mass-damper subsystems and the disc as a continuous bar. This modeling concept increases both the ease of analytical expression and the insight provided into the behavior of the real-world systems. This paper describes the analytical expression of this model and its implementation in Matlab. A parameter variation study yielded results that agree with existing research, which serves to validate the fundamental principles of this proposed modeling method.

A Novel Arc Welding Power Supply With Improved Power Factor Correction, Benjamin H. Tan

Master's Theses

This paper presents the design and development of a novel Arc Welding Power Supply utilizing a modified two-switch forward converter topology. The proposed design improves the power quality by improving power factor to near unity and reducing total harmonic distortion. State space analysis of the proposed circuit showed that the circuit followed a boost-buck input output relationship. Simulation of the circuit was first implemented in LTspice to verify the functionality of the new topology. Hardware implementation of the proposed design was built on a scaled-down prototype for a proof-of-concept of the new topology. The prototype specifications were created for a …

A Time Integration Method Of Approximate Particular Solutions For Nonlinear Ordinary Differential Equations, Cyril Ocloo

Master's Theses

We consider a time-dependent method which is coupled with the method of approximate particular solutions (MAPS) of Delta-shaped basis functions and the method of fundamental solutions (MFS) to solve nonlinear ordinary differential equations. Firstly, we convert a nonlinear problem into a sequence of time-dependent non-homogeneous boundary value problems through a fictitious time integration method. The superposition principle is applied to split the numerical solution at each time step into an approximate particular solution and a homogeneous solution. Delta-shaped basis functions are used to provide an approximation of the source function at each time step. The purpose of this is to …

Sedimentary Dynamics And Water Quality In Floodplains Of The Lower Mississippi River Near Natchez, Mississippi, During The 2018 And 2019 Floods, Jansen Costello

Master's Theses

The Lower Mississippi River (LMR) near Natchez, Mississippi, experienced intervals of major flooding during the 2018 and 2019 water years. While federal agencies sample sediment and water quality in the main LMR channel, little is known about sedimentary dynamics, water quality, and nutrient concentrations of the overbank water column within the embanked LMR floodplain. These data are needed to support ecological floodplain restoration efforts and provide context for downstream concerns including sediment delivery to coastal zones and hypoxia in the Gulf of Mexico.

This study monitored the overbank flood pulses and associated sediment deposition along the LMR embanked floodplain during …

Educational Equity And Informal Stem Field Trip Programming, Sal Alper

Master's Theses

Informal STEM field trip programming is a large, yet under-researched area of the education landscape. Informal STEM education providers are often serving a more privileged section of society, leading to a risk of perpetuating inequalities seen throughout the education landscape. In an attempt to address the lack of research, this thesis explores the relationship between educational equity and informal STEM field trips. The intention was to collect data using a critical ethnography approach to the methods of qualitative questionnaire and interviews of informal STEM educators. A change in circumstances from the global pandemic of COVID-19 caused a shift in this …

Neural Network Pruning For Ecg Arrhythmia Classification, Isaac E. Labarge

Master's Theses

Convolutional Neural Networks (CNNs) are a widely accepted means of solving complex classification and detection problems in imaging and speech. However, problem complexity often leads to considerable increases in computation and parameter storage costs. Many successful attempts have been made in effectively reducing these overheads by pruning and compressing large CNNs with only a slight decline in model accuracy. In this study, two pruning methods are implemented and compared on the CIFAR-10 database and an ECG arrhythmia classification task. Each pruning method employs a pruning phase interleaved with a finetuning phase. It is shown that when performing the scale-factor pruning …