Digital Commons Network^™

Transformation Groups And The Method Of Darboux, Brandon P. Ashley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In the study of partial differential equations (PDE), one is often concerned as to whether or not explicit solutions can be obtained via various integration techniques. One such technique, known as the method of Darboux, has had particular success in solving nonlinear problems as demonstrated by the classical works of Goursat. Recently, Anderson, Fels, and Vassiliou provided a far-reaching generalization of Vessiot’s group-theoretic interpretation of the method of Darboux. This generalization allows for the characterization of Darboux integrable systems in terms of fundamental geometric invariants as well as the construction of Darboux integrable systems in general.

In this work, we …

Essays Related To Water Transfer And Water Sharing: The Past And The Present, Arpita Nehra

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This dissertation explores the impacts of resource procurement on economic growth and urbanization in a county through a historical case study, moving on to discuss the welfare impacts of resource-sharing in two regions. The first two essays explore the impact of the Owens Valley water transfer in the 1900s on the urban sprawl and the economic growth of Los Angeles. The main contribution that the first two essays make is to present an empirical analysis on the impact of procurement of resources on the economy. The third essay examines the welfare impacts of a proposed water sharing and development project. …

Efficacy Of Professional Development Models In Dismantling Scientific Misconceptions, Tyler Hansen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Scientific misconceptions held by educators are both common and well documented. As science education becomes more and more important to students, it is evident that there is a need to not only identify scientific misconceptions held by teachers as a means of bettering the education of students, but also determine effective methods of deconstructing them. Although studies have indicated that professional development can assuage the prevalence of misconceptions held by teachers, there is a dearth in the literature of what makes these professional developments effective. Therefore, this study investigated which models of professional development are most effective in dismantling misconceptions …

Lithological And Geochemical Characterization Of Ramp Sediments And A Depositional Model Of The Ordovicain Garden City Formation, Northeastern Utah, Kenneth W. Kehoe

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Ordovician Garden City Formation is a mostly marine limestone rock formation deposited in what is known today as the Northern Utah Basin in North America ~485.5 million years ago. Previous research on the Pogonip Group, a time equivalent rock formation located in the Ibex Basin south of the Northern Utah Basin, has identified nine cycles of sea-level fall and rise. However, these nine sea-level cycles have proven difficult to identify within the Garden City Formation due to the limited contrast between rock types within the rock formation. Previous research on the Garden City has approximated these sea-level cycles through …

Characteristic Of The Dynamics Of Disorder In Crystalline And Amorphous Materials, Amir Behbahanian

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This work provides the evidence to apply simulation methods that are applicable to systems with structural randomness to simulate crystalline materials at high temperatures. My work not only open the avenue to expand the simulation capability of materials but also provides insight to the physics of vibrations of atoms under different temperature and for different types of materials. I have also evaluated the reliability of Molecular Dynamics simulations at the frequency level and found that theses types of simulations, despite the previous belief, are reliable at low temperatures but up to a measurable frequency. In addition, the result of my …

On The Geometry Of The Moduli Space Of Certain Lattice Polarized K3 Surfaces And Their Picard-Fuchs Operators, Michael T. Schultz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

K3 surfaces have a long and rich study in mathematics, and more recently in physics via string theory. Often, K3 surfaces come in multiparameter families - the parameters describing these surfaces fit together to form their own geometric space, a so-called moduli space. In particular, the moduli spaces of K3 surfaces equipped with a lattice polarization can sometimes be constructed explicitly, which subsequently reveals important information about the original K3 surface.

In this work, we construct such families explicitly from certain rational elliptic surfaces via the so-called mixed-twist construction of Doran & Malmendier, which in turn produces the moduli …

The Roles And Responsibilities Of The Covid-19 Elementary Principal In Relation To Job Descriptions And Utah School Leadership Evaluation Metrics: A Case Study, Sarah R. Nielsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to examine the roles and responsibilities of elementary school principals in relation to how they are evaluated and what is included in their job descriptions during the COVID-19 pandemic. Because of the numerous policies that surround education and the COVID-19 pandemic, this study examined elementary school principals from a single school district in Utah. Seven principals agreed to participate in an interview that asked principals about their day-to-day responsibilities as a principal and how COVID-19 affected those responsibilities. Six principals agreed to participate in a daily reflection on how much time they spent participating …

Absolute Neutral Densities And Temperatures And Their Climatologies In The Middle Atmosphere Using An Optimal Estimation Method With Rayleigh-Scatter Lidar Observations Obtained At Utah State University, Jonathan L. Price

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Earth’s atmosphere is comprised of layers which can be defined by their temperature characteristics. These layers are the troposphere, stratosphere, mesosphere and thermosphere. The region where life exists is in the troposphere, however the study of the layers above is important as changes in these regions can directly impact, or indicate significant changes in, weather in the troposphere. The mesosphere is the least well-known region because it is the most difficult to observe. One of the best tools for observing this region is the Rayleigh-scatter lidar. It is capable of remotely observing the entirety of the mesosphere with good …

Valley Bottom Inundation Patterns In Beaver-Modified Streams: A Potential Proxy For Hydrologic Inefficiency, Karen Bartelt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

For centuries river management and land use actions in North America have caused widespread stream degradation where water now flows downstream with artificially high efficiency. When present, beaver dams slow the flow of water and decrease the efficiency of water conveyance through the landscape. These effects are often to the benefit of the function of natural physical processes and ecology of the stream. The benefits provided by beaver dams have been well studied at small scales, but the methods that these studies rely on are often expensive and time consuming and consequently not feasible to deploy at larger spatial scales …

Achieving A Sequenced, Relational Query Language With Log-Segmented Timestamps, M. A. Manazir Ahsan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In a relational temporal database, typically each row of each table has a period timestamp to indicate the lifetime of that row. In order to evaluate a query in a temporal database, sequenced semantics comes into play. The semantics stipulates that the query must be evaluated simultaneously in each time instant using the data rows available at that point of time. Existing researches have proposed changes in the query evaluation engine to achieve sequenced semantics. In this paper we show a way to support sequenced semantics without modifying the query engine. We propose a noble construction log-segmented label to represent …

Gps-Denied Navigation Using Synthetic Aperture Radar Images And Neural Networks, Teresa White

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Unmanned aerial vehicles (UAV) often rely on GPS for navigation. GPS signals, however, are very low in power and easily jammed or otherwise disrupted. This paper presents a method for determining the navigation errors present at the beginning of a GPS-denied period utilizing data from a synthetic aperture radar (SAR) system. This is accomplished by comparing an online-generated SAR image with a reference image obtained a priori. The distortions relative to the reference image are learned and exploited with a convolutional neural network to recover the initial navigational errors, which can be used to recover the true flight trajectory throughout …

Roadway-Embedded Transmitters And Multi-Pad Receivers For High Power Dynamic Wireless Power Transfer, Benny J. Varghese

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Electric vehicles (EVs) offer considerable economic and environmental benefits to society. Despite the decreasing vehicle costs and increasing range of newer EVs, the problem of range anxiety still exists. Range anxiety, at its core, is an issue of charging speeds rather than a concern about the driving range. Dynamic wireless charging of EVs is seen as a potential solution to this issue of range anxiety. Further, wireless charging technology also helps the push towards level 5 autonomy and opens new opportunities for how an EV can be utilized.

Dynamic wireless power transfer (DWPT) systems typically require a high initial investment …

High-Magnification Digital Image Correlation Techniques For Aged Nuclear Fuel Cladding Testing, Robert Scott Hansen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nuclear fuel cladding in light water reactors, often made of zirconium alloys, is naturally made more brittle by exposure to the water coolant during normal reactor operation. However, this embrittlement by zirconium hydrides changes the mechanical behavior of the cladding material, affecting how it will deform and what may cause it to fail. Because the cladding already has different properties in different material directions, mechanical testing also needs to be direction specific. In addition, to understand the effects that these microscale hydride features have, measurements of deforming cladding need to be at a microscale. This dissertation describes several high-magnification innovations …

Candidate Ideology And Small Donor Contributions, Ryan Kobe

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

While individual citizens are the biggest source of campaign fundraising in Senate and House elections, previous research has focused on individuals donating over the reporting limit of $200. The Federal Elections Committee now makes available data on individuals who donate less than $200, and as these donors take on a bigger role in congressional fundraising, a new analysis of donor motivations is needed. This thesis investigates if and how candidate ideology is related to amount contributed. Specifically, I ask whether the dollar amount of contributions changes depending on how conservative or liberal a candidate is. These results have important implications …

The Internal Charge Evolution Of Multilayered Materials Undergoing Mono-Energetic Electron Bombardment, Gregory Wilson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The charging of multilayer materials as related to the charging of spacecraft is one of the primary concerns related to activities in the space environment. To understand how multilayer materials undergoing electron bombardment charge, an in-depth study of energy-dependent material properties must be undertaken. These properties include the electron penetration depth, secondary electron emission, charge transport and electrostatic discharge. By using energy dependent models of these properties, along with the geometry of the system, multilayer models can be developed to predict the time evolution of the internal charge distribution. Using these models, the net surface potential and the measurement of …

Classical Venturi Meter Performance Downstream Of The Through Leg Of A Tee Junction, Matthew P. Day

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this research was to analyze the accuracy of a Classical Venturi meter installed downstream of the through leg of a tee junction. A flowmeter that functions inaccurately due to improper installation may cause revenue loss for any company or organization involved in extraction, transportation, production, or purchasing of fluid resources and products. This research used physical data coupled with data produced by numerical models to determine how to correct the Classical Venturi meter’s inaccuracies created by this particular installation.

Results show the capability of measuring the flow rate accurately was greatly affected when most of the flow …

The Effect Of Bit Depth On High Temperature Digital Image Correlation Measurements, Steven Robert Jarrett

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Digital Image Correlation (DIC) is a camera-based method of measuring mechanical displacement and strain which is commonly used in high-temperature experiments due to its ability to take contactless measurements. High-temperature DIC is challenging due to light emitted from the sample which can saturate the camera sensor. Blue-DIC and UV-DIC have been developed to minimize this effect, but the maximum sample temperature range of DIC remains a function of the camera and camera settings. Bit depth, also referred to as color depth or number of bits, is an important camera setting which affects the dynamic range of an image, but which …

Peer-To-Peer Feedback: An Instructional Strategy In Teacher Evaluation, Brady L. Ridge

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Over the last several decades there have been federal movements in education which place more accountability on schools and consequently their principals. Principals have many responsibilities which vary from administrative duties to improving teaching in their schools. As a result, principals are often asked to do more than they believe they have time to accomplish. Peer-to-peer feedback is a practice that principals can use to help evaluate, and more importantly, help teachers improve their teachers' teaching. This multi-case or multi-school qualitative study researched the practice of peer-to-peer feedback at two elementary schools. The purpose was to understand how peer-to-peer feedback …

Examining Segregation Between Chinese And Euroamerican Residences Using Suitability Modeling Within The Built Environment At Terrace, Utah: A Case Study, Kelly N. Jimenez

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Suitability modeling is a useful approach for exploring human interactions with their environments. Within a geographic information system (GIS) environment, locations are weighted relative to each other, resulting in a landscape hierarchy that displays regions from least to most suitable. Suitability modeling is used in various disciplines, from urban planning to natural resources, but a gap exists in research concerning social human behavior. This method can especially contribute to the investigation of social inequality at archaeological sites by considering multiple attributes within a site. In this thesis, I use method to determine social inequality between cultural groups at the historic …

Equivalence: A Covariantly Constant Problem In General Relativity, Jaren Hobbs

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

In studying the space-time structures described by Einstein’s theory of general relativity, it is often useful to identify particular properties referred to as geometrical invariants. These are attributes of the space-times which do not change regardless of the underlying coordinate systems used to study them. This project is part of a larger effort to catalogue space-times studied in general relativity. Specifically, computational software was used to identify structures known as covariantly constant vector fields.

Forecasting Stock Market Prices: A Machine Learning Approach, Abraham Alhomadi

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

There has been extensive literature written about the efficiency of the stock market. Practitioners and academicians have debated whether investors can exploit publicly available information to generate excess returns. Clearly predicting the stock market’s return with high accuracy has been enormously difficult, but we are interested in contributing to the continuous exploration of the efficiency of the stock market using machine learning techniques. We also want to examine the relationship between our dataset’s macroeconomic indicators and foreign nations’ stock markets with our target feature—the S&P 500. In this paper, we will be using supervised machine learning models, like Linear Regression, …

Limited Progress In Nutrient Pollution In The U.S. Caused By Spatially Persistent Nutrient Sources, Rebecca J. Frei, Gabriella M. Lawson, Adam J. Norris, Gabriel Cano, Maria Camila Vargas, Elizabeth Kujanpää, Austin Hopkins, Brian Brown, Robert Sabo, Janice Brahney, Benjamin W. Abbott

Watershed Sciences Faculty Publications

Human agriculture, wastewater, and use of fossil fuels have saturated ecosystems with nitrogen and phosphorus, threatening biodiversity and human water security at a global scale. Despite efforts to reduce nutrient pollution, carbon and nutrient concentrations have increased or remained high in many regions. Here, we applied a new ecohydrological framework to ~12,000 water samples collected by the U.S. Environmental Protection Agency from streams and lakes across the contiguous U.S. to identify spatial and temporal patterns in nutrient concentrations and leverage (an indicator of flux). For the contiguous U.S. and within ecoregions, we quantified trends for sites sampled repeatedly from 2000 …

Stochastic Lightning Damage Prediction Of Carbon/Epoxy Composites With Material Uncertainties, S.Z.H. Shah, Juhyeong Lee

Mechanical and Aerospace Engineering Faculty Publications

This study presents a novel stochastic modeling framework predicting lightning thermal damage in carbon/epoxy composites. The stochastic lightning damage model (SLDM) was developed with random distributions of composite’s electrical conductivity and void. The Box-Muller transformation was applied to generate random in-plane and through-thickness electrical conductivities with Gaussian distributions. The SLDM suggested that the predicted lightning thermal damage to carbon/epoxy composites increased slightly with the use of stochastic electrical conductivity, but the presence of voids did not significantly affect the damage development. The predicted size and shape of lightning thermal damage agreed fairly well with experimental results. In addition, the proposed …

The Utah Statesman, November 22, 2021, Utah State University

The Utah Statesman

Weekly student newspaper of Utah State University in Logan.

Charge Transport In Dielectric: The Pulsed Electroacoustic Method, Zachary Gibson

Physics Student Research

Understanding and predicting charge accumulation and transport in dielectric materials is vital in applications where excess charge can accumulate including semiconductor devices, high-power electronic devices, high voltage DC cabling, high-energy physics facilities, plasma chambers, and spacecraft charging. Excess charge accumulation may result in electrostatic discharge events, which are the leading cause of spacecraft failure due to the space environment. The pulsed electroacoustic method allows you to “pop the hood” and non-destructively directly measure the embedded charge distributions in dielectric materials. Charge transport in disordered dielectric materials, measurements with the pulsed electroacoustic system, and comparison to models will be presented.

The Utah Statesman, November 15, 2021, Utah State University

The Utah Statesman

Weekly student newspaper of Utah State University in Logan.

Geodetic Model For Teaching Motion On The Earth's Spheroidal Surface, Boyd F. Edwards, John M. Edwards

All Physics Faculty Publications

We explore the forces that shape our spheroidal Earth and the forces that govern the motion of a puck that slides without friction on its surface. The Earth's stable spheroidal shape (apart from small-scale surface features) is determined by balancing the gravitational forces that hold it together against the centrifugal forces that try to tear it apart. The motion of a puck on its surface differs profoundly from motion on a sphere because the Earth's spheroidal deformations neutralize the centrifugal and gravitational forces on the puck, leaving only the Coriolis force to govern the motion. Yet the Earth's spheroidal deformations …

Rural Teachers' Cultural And Epistemic Shifts In Stem Teaching And Learning, Colby Tofel-Grehl, Kristin A. Searle, Andrea Hawkman, Beth L. Macdonald, Mario I. Suárez

Teacher Education and Leadership Faculty Publications

This article focuses on the ways in which integrated curriculum can improve STEM teaching and learning within rural spaces. Using a design-based research approach, this study focuses on rural teachers' experiences of professional learning and development training as they learn to engage computing and maker technologies in their elementary classrooms as tools for teaching students about difficult histories of immigration, migration, and forced relocation across the United States.

The Utah Statesman, November 8, 2021, Utah State University

The Utah Statesman

Weekly student newspaper of Utah State University in Logan.

Using Dyadic Observation To Explore Equitable Learning Opportunities In Classroom Instruction, Alyson L. Lavigne, Thomas L. Good

Teacher Education and Leadership Faculty Publications

Because of poverty, many children do not receive adequate prenatal care, nutrition, or early childhood education. These inequities combine to ensure that many students enter school with considerably less academic content knowledge and skills for learning than their peers. Teachers and schools did not create these gaps, but they must address them. The impact of schools in reducing gaps has been explored for decades only to yield inconsistent findings. One possible reason for these contradictory results is because these studies ignore classroom process. We argue for the inclusion of process in research on opportunity and achievement gaps to better articulate …