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All Graduate Theses and Dissertations

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Full-Text Articles in Physical Sciences and Mathematics

Serendipity Shape Function For Hybrid Fluid/Kinetic-Pic Simulations, Trevor V. Taylor Dec 2022

Serendipity Shape Function For Hybrid Fluid/Kinetic-Pic Simulations, Trevor V. Taylor

All Graduate Theses and Dissertations

The Sun in our solar system and stars are capable of generating enormous amounts of energy. The process by which these gaseous, celestial bodies are able to produce such large amounts of energy is called thermonuclear fusion. Fusion happens when particles collide with one another at energy levels high enough to overcome the Coulomb force and then release vast amounts of energy. Plasma, the fourth state of matter, is the natural state of stars. Plasma is an ionized gas that consists of negatively and positively charged particles. Stars, which have immense mass, can confine the plasma through their gravity to …


Bedrock Geology Map Of The Naomi Peak 7.5' Quadangle, Cache County, Utah And Novel Age Constraints On Its Cambrian Strata, Hannah R. Cothren Dec 2022

Bedrock Geology Map Of The Naomi Peak 7.5' Quadangle, Cache County, Utah And Novel Age Constraints On Its Cambrian Strata, Hannah R. Cothren

All Graduate Theses and Dissertations

Geologists use various “rock-clocks” in order to interpret the timing and tempo of events in Earth’s history. These include global geochemical events in the oceans (chemostratigraphy), the evolution of certain fossil species (trilobite biostratigraphy), and the radiogenic decay of uranium to lead in certain mineral such as zircon (U-Pb geochronology). Integrating these methods in the stratigraphic record in one location can provide a well-constrained timeline for a select part of the Geologic, or Deep Time, record. This technique is especially important in the Cambrian Period (538.8 to 486.9 million years; Ma), which sets the stage for life today with the …


Investigating The Use Of Quartz Luminescence And Rock-Color Alteration To Characterize Wildfire Exposure; Applied To The 2020 Mangum Fire, Kaibab Plateau, Arizona, April I. Phinney Dec 2022

Investigating The Use Of Quartz Luminescence And Rock-Color Alteration To Characterize Wildfire Exposure; Applied To The 2020 Mangum Fire, Kaibab Plateau, Arizona, April I. Phinney

All Graduate Theses and Dissertations

Wildfires appear to be increasing in size, severity, and frequency. Land managers need information on past wildfire behavior to make effective and adaptive land management plans. However, there are only a few techniques and data sources that provide information on past fire heating. This study aims to provide new methods to equip managers with a more robust understanding of historic and modern fire behavior. Fire behavior is assessed using novel methods that can assess soil and rock response to past wildfire heat exposure.

This study examined samples from the 2020 Mangum Fire, in northern Arizona. Sediment and rock were gathered …


Bifurcations And Hysteresis In The Dynamics Of Small Populations Of Spherical Magnets, Peter T. Haugen Dec 2022

Bifurcations And Hysteresis In The Dynamics Of Small Populations Of Spherical Magnets, Peter T. Haugen

All Graduate Theses and Dissertations

If you heat up some kinds of metals and then cool them down next to a magnet, they will be a magnet when they cool, but if they cool down away from a magnet, they will just be a lump of metal. This is an example of hysteresis and it’s very important for lots of technology. Another example of hysteresis might be a water tower pump that turns on when the tower is nearly empty and keeps going until the tower is nearly full. Whether or not the pump is on when the tower is half full depends on what …


Pleistocene Deposits Of Lower Wahweap Creek And Its Tributaries, Southern Utah, Noah Slade Dec 2022

Pleistocene Deposits Of Lower Wahweap Creek And Its Tributaries, Southern Utah, Noah Slade

All Graduate Theses and Dissertations

The famous landscapes of the Colorado Plateau have been created over millions of years, primarily by erosive forces of wind and water. Interruptions in the long-term erosion of the landscape occur when streams gain more sediment than they can transport, which causes deposition along channels and floodplains. The resulting sequences of terrace deposits are used by geologists to study when and how river systems have evolved.

Mammoth bones were recently discovered in stream deposits along Wahweap Creek, a tributary of the Colorado River in southern Utah. Previous work indicates that the deposits pre-date the last ice age, making it one …


Investigating Atmospheric Gravity Waves Using 3-Dimensional Spectral Analysis, Kenneth I. Zia Dec 2022

Investigating Atmospheric Gravity Waves Using 3-Dimensional Spectral Analysis, Kenneth I. Zia

All Graduate Theses and Dissertations

Atmospheric gravity waves (GW) are generated from the ground and go into the upper layers of the atmosphere where space begins. These waves have strong effects on the temperature and circulation of the Earth’s atmosphere. The temperature changes caused by these waves are observed through special cameras looking at light that the Earth’s atmosphere naturally emit at night. One of these cameras is placed at McMurdo Station, Antarctica where the long nights are used to see these waves longer than anywhere else. The images captured there are automatically analyzed to determine wave properties to better understand how often they are …


Functional Characterization Of The Newly Discovered Type V Crispr-Cas Protein Cas12a2, Dylan J. Keiser Dec 2022

Functional Characterization Of The Newly Discovered Type V Crispr-Cas Protein Cas12a2, Dylan J. Keiser

All Graduate Theses and Dissertations

Similarly to people, bacteria are under the treat of infection by viruses. To circumvent these threats, bacteria evolve complex immune systems. Our understanding of some of these immune systems has led to many advancements in the field of Biotechnology including tools that made expressing proteins for study in a lab easier, tools that revolutionized the feasibility of gene editing, and tools that could change the way we think about viral diagnostics and cancer therapeutics. A certain type of immune system that bacteria use to fight virus is called a CRISPR system. Presented here is work to understand the function of …


Graviweak Theory In Bicomformal Space, Mubarak Ukashat Dec 2022

Graviweak Theory In Bicomformal Space, Mubarak Ukashat

All Graduate Theses and Dissertations

There are four basic forces in nature: the electromagnetic force, which accounts for interactions of particles with charges; the weak force, which is responsible for radioactive decay; the strong force, which holds the particles inside a nucleus tightly bound together; and the gravitational force, which is responsible for keeping us on our beautiful planet, Earth and holding together our entire solar system. Physicists have been on the hunt for a theory that can single-handedly explain all these forces under the same underlying mathematical formulation. So far, physicists have suceeded in unifying the electromagnetic and weak forces in what is called …


Power Approximations For Generalized Linear Mixed Models In R Using Steep Priors On Variance Components, Sydney Geisler Dec 2022

Power Approximations For Generalized Linear Mixed Models In R Using Steep Priors On Variance Components, Sydney Geisler

All Graduate Theses and Dissertations

When designing an experiment, researchers often want to know how likely they are to detect statistically significant effects in the resulting data, i.e., they want to estimate their statistical power. The probability distribution method is a flexible way to do this, and it is currently implemented in the statistical software package SAS. This method requires a hypothetical data set (showing the magnitude of hypothesized effects) and constant values of variance components, which are critical elements of the statistical models used. The statistical software package R is increasingly popular, but the probability distribution method has not yet been implemented in R, …


Statistical Challenges And Methods For Missing And Imbalanced Data, Rose Adjei Dec 2022

Statistical Challenges And Methods For Missing And Imbalanced Data, Rose Adjei

All Graduate Theses and Dissertations

Missing data remains a prevalent issue in every area of research. The impact of missing data, if not carefully handled, can be detrimental to any statistical analysis. Some statistical challenges associated with missing data include, loss of information, reduced statistical power and non-generalizability of findings in a study. It is therefore crucial that researchers pay close and particular attention when dealing with missing data. This multi-paper dissertation provides insight into missing data across different fields of study and addresses some of the above mentioned challenges of missing data through simulation studies and application to real datasets. The first paper of …


Data Visualization, Dimensionality Reduction, And Data Alignment Via Manifold Learning, Andrés Felipe Duque Correa Dec 2022

Data Visualization, Dimensionality Reduction, And Data Alignment Via Manifold Learning, Andrés Felipe Duque Correa

All Graduate Theses and Dissertations

The high dimensionality of modern data introduces significant challenges in descriptive and exploratory data analysis. These challenges gave rise to extensive work on dimensionality reduction and manifold learning aiming to provide low dimensional representations that preserve or uncover intrinsic patterns and structures in the data. In this thesis, we expand the current literature in manifold learning developing two methods called DIG (Dynamical Information Geometry) and GRAE (Geometry Regularized Autoencoders). DIG is a method capable of finding low-dimensional representations of high-frequency multivariate time series data, especially suited for visualization. GRAE is a general framework which splices the well-established machinery from kernel …


Investigations Of Prokaryotic Defense Systems, Hannah Domgaard Dec 2022

Investigations Of Prokaryotic Defense Systems, Hannah Domgaard

All Graduate Theses and Dissertations

Bacteria are constantly threatened with infection by mobile genetic elements (MGE) such as bacteriophage and plasmids. Bacteriophage and plasmids require the bacteria's cellular infrastructure to replicate their genomes. Rampant replication can lead to cell death which is one reason why bacteria have developed a diverse array of immune systems to prevent or limit infection. This thesis studies three types of bacterial immune systems, type IV-A CRISPR-Cas (Clustered Regularly Interspaced Short Palindromic Repeat –CRISPR associated), type V-A2 CRISPR-Cas systems, and Wadjet systems.

The type IV-A system lies adjacent to a dinG-like helicase gene. Research has shown that this system can target …


Development Of In Situ Second-Order Nonlinear Optical Scatterings For Molecular Behaviors At Aerosol Surfaces, Yuqin Qian Dec 2022

Development Of In Situ Second-Order Nonlinear Optical Scatterings For Molecular Behaviors At Aerosol Surfaces, Yuqin Qian

All Graduate Theses and Dissertations

Aerosol particles are one of the most important components of the atmosphere. During the growth of aerosol particles, they directly or indirectly affect air quality, human health, and environmental chemistry. Therefore, understanding the chemical and physical properties of such particles is an important scientific, engineering, and medical issue. The growth of aerosol particles in the atmosphere is closely related to the chemical structure at its surface, as well as the heterogeneous reactions which take place at and below the particle’s surface. However, there is a lack of suitable surface-specific analytical techniques which directly measure the chemical structure of aerosol particle …


Design Of Environment Aware Planning Heuristics For Complex Navigation Objectives, Carter D. Bailey Dec 2022

Design Of Environment Aware Planning Heuristics For Complex Navigation Objectives, Carter D. Bailey

All Graduate Theses and Dissertations

A heuristic is the simplified approximations that helps guide a planner in deducing the best way to move forward. Heuristics are valued in many modern AI algorithms and decision-making architectures due to their ability to drastically reduce computation time. Particularly in robotics, path planning heuristics are widely leveraged to aid in navigation and exploration. As the robotic platform explores and navigates, information about the world can and should be used to augment and update the heuristic to guide solutions. Complex heuristics that can account for environmental factors, robot capabilities, and desired actions provide optimal results with little wasted exploration, but …


Normative Evaluations Of Resource Conditions: The Influence Of Visitor Characteristics And Implications For Recreation Management In Urban-Proximate Parks, Jordan E. Nesbitt Dec 2022

Normative Evaluations Of Resource Conditions: The Influence Of Visitor Characteristics And Implications For Recreation Management In Urban-Proximate Parks, Jordan E. Nesbitt

All Graduate Theses and Dissertations

Urban-proximate parks and protected areas provide a unique recreation landscape to individuals living in and near urban centers. They have been shown to provide similar recreation experiences to traditionally studied parks and protected areas such as National Parks, National Forests and Wilderness areas. This study takes place in a set of four urban-proximate parks in Orange County, California, USA. These parks are designated as urban-proximate because they are located within 100 miles of an urban center with 1 million or more people. Using norm theory, a well vetted social science theory, this work sought to identify thresholds of acceptability for …


Carbon Sinks And Sources In Great Salt Lake: Consequences Of Declining Lake Levels, Melissa Cobo Arias Dec 2022

Carbon Sinks And Sources In Great Salt Lake: Consequences Of Declining Lake Levels, Melissa Cobo Arias

All Graduate Theses and Dissertations

Globally, saline lakes are experiencing declining water level as a consequence of climate change, water diversions for human consumption, and management strategies that do not account for changing climate and drought conditions. Great Salt Lake (GSL) is a large saline lake in Utah, USA, and is, as most saline lakes, experiencing decreasing lake levels which may impact local carbon cycling. It is unknown how lakebed drying affects processes that control carbon sequestration and carbon emissions to the atmosphere. The goal of this research was to measure various biological processes that use, create, and transform carbon in GSL to understand the …


Old-Growth Forest Dynamics After Fire And Drought In The Sierra Nevada, California, Usa, Kendall M.L. Becker Dec 2022

Old-Growth Forest Dynamics After Fire And Drought In The Sierra Nevada, California, Usa, Kendall M.L. Becker

All Graduate Theses and Dissertations

Understanding forest ecosystems is important because forests cover approximately one-third of Earth’s land area, store half of Earth’s carbon, shelter half of Earth’s species, and absorb a quarter of new anthropogenic carbon emissions, slowing climate change. This dissertation provides insight into future forest habitat, fuels, species composition, and structure by investigating what happens to snags, seedlings, and trees in an old-growth forest after a low- to moderate-severity fire.

Chapter II explores how low- to moderate-severity fire changes snag fall rates. Predicting how long snags will remain standing after fire is essential for managing habitat, understanding chemical cycling in forests, and …


Human Appropriation Of Net Primary Production Through Crops, Grazing, And Forestry In The U.S. From 1997 To 2012, Suman Paudel Dec 2022

Human Appropriation Of Net Primary Production Through Crops, Grazing, And Forestry In The U.S. From 1997 To 2012, Suman Paudel

All Graduate Theses and Dissertations

This dissertation conducts a county-level analysis of human appropriation of net primary production (HANPP) harvested from crops, timber and grazing in the conterminous United States in the years 1997, 2002, 2007 and 2012. This study consists of three manuscripts (Chapters 2, 3, and 4). The first study quantifies net primary production in US counties in 1997, 2002, 2007 and 2012. The detailed HANPP study conducted concludes that HANPP is a valuable footprint tool for analyzing land use intensity and agricultural ecosystems. The second manuscript shows how HANPP is an improved or modernized ecological footprint and is a sustainable indicator as …


Temperature Dependent Density Of States Models And Compiled Data For Radiation Induced Conductivity, Jodie Gillespie Dec 2022

Temperature Dependent Density Of States Models And Compiled Data For Radiation Induced Conductivity, Jodie Gillespie

All Graduate Theses and Dissertations

Radiation Induced Conductivity (RIC) is the change in conductivity of a material due to bombardment from incident high energy radiation. RIC has consistently been found to follow a standard power law relation, 𝜎𝑅𝐼𝐶(𝑇) = 𝑘𝑅𝐼𝐶(𝑇)𝐷̇∆(𝑇), between conductivity, 𝜎𝑅𝐼𝐶 and adsorbed dose rate, Ḋ. 𝑘𝑅𝐼𝐶(𝑇) and ∆(𝑇) are material dependent parameters. Previous RIC models were developed in the 𝑇→0 limit. Now expanded models are developed in the low temperature limit (within a few 𝑘𝐵𝑇 of the effective Fermi level) by approximating the Fermi-Dirac equation within a few 𝑘𝐵𝑇 of the …


River Response To Sediment Supply: The Sand Bed Case, Christina M. Leonard Dec 2022

River Response To Sediment Supply: The Sand Bed Case, Christina M. Leonard

All Graduate Theses and Dissertations

Effective management of in-channel and floodplain habitat requires an ability to forecast river response to changes in water and sediment supply. These changes may result from dam construction/decommissioning, changes in reservoir operations, or changes in grazing or forestry practices. If a change in water and sediment supply causes sediment to be delivered faster than the channel’s capacity to transport it, sediment will accumulate in the reach, leading to changes in channel form and increasing the potential for flooding. A decrease in sediment supply relative to transport capacity can lead to channel incision. The extent and timing of sediment accumulation or …


Late Pleistocene Piedmont Records In The Grand Staircase Region, Southern Utah, Alexander K. Short Dec 2022

Late Pleistocene Piedmont Records In The Grand Staircase Region, Southern Utah, Alexander K. Short

All Graduate Theses and Dissertations

Today the climate in the southwestern United States is arid, characterized by desert landscapes and habitats, periods of drought, and arroyo streams that frequently fill with, and erode, through fine riverbed sediments. A series of cliffs and benches rising from the Grand Canyon to the southern plateaus of Utah, known as the Grand Staircase - home to Kodachrome Basin State Park, Bryce Canyon, are a classical example of this environment as we know it today. However, a record spanning the past 300 thousand years is preserved on the steps of the staircase indicating periods in the past where the climate …


Relativistic, Continuum Drift-Kinetic Capability In The Nimrod Plasma Fluid Code, Tyler Markham Dec 2022

Relativistic, Continuum Drift-Kinetic Capability In The Nimrod Plasma Fluid Code, Tyler Markham

All Graduate Theses and Dissertations

A ”runaway” electron is an electron that, through a self-reinforcing process, accelerates to relativistic speeds. At multiple points during tokamak discharges, relativistic runaway electron (RE) beams can form. RE beams pose a serious risk in the form of severe damage to plasma facing components in ITER and future burning plasma reactors. Early RE studies used simplified geometric and transport models, but enabled feedback on the overall plasma evolution. This feedback is important for understanding the evolution of the RE current column. The work in this thesis is an important step toward self-consistently evolving an RE distribution in the plasma fluid …


Investigating Factors That Impact Income Generation And Distribution In Western National Park Gateway Communities, Elizabeth Depew Aug 2022

Investigating Factors That Impact Income Generation And Distribution In Western National Park Gateway Communities, Elizabeth Depew

All Graduate Theses and Dissertations

Many rural towns in the western united states have come to be defined by high levels of tourism, seasonal residents, and migration driven by the desire to be close to natural amenities and the higher quality of life they afford. This shift is especially apparent in communities that are “gateways” to natural amenities such as national parks. Embracing this shift towards the “New West,” many community planners have heralded amenity-led development as a remedy to the waning feasibility of relying on agriculture and extractive industries. However, anecdotal evidence and several case studies indicate the factors which make these gateway communities …


Natural And Experimental Slow Slip Observed Along Shallow Hematite Faults, Alexandra A. Dimonte Aug 2022

Natural And Experimental Slow Slip Observed Along Shallow Hematite Faults, Alexandra A. Dimonte

All Graduate Theses and Dissertations

Fault slip relieves stress in the shallow crust by slipping suddenly during earthquakes, but some faults also slip slowly in between earthquakes. Exhumed faults, brought up to the Earth’s surface from depth, preserve a record of fault processes and slip rates informed by fault rock structures, textures, and chemistry. Hematite, a common iron oxide mineral that precipitates on fault surfaces, exhibits crystal textures that potentially indicate past slip rate. Hematite can be dated using the radioisotopic system of (U-Th)/He thermochronometry, which constrains the time when He is trapped within a crystal, a process that is a function of temperature. Exhumed …


Conservation Genetics Of A Declining Bumble Bee In Western North America; The Influence Of Geography, Dispersal Limitation, And Anthopogenic Activity, Ashley T. Rohde Aug 2022

Conservation Genetics Of A Declining Bumble Bee In Western North America; The Influence Of Geography, Dispersal Limitation, And Anthopogenic Activity, Ashley T. Rohde

All Graduate Theses and Dissertations

Conservation biology addresses the problem of species loss by identifying species in need of protection. Conservation biology has subfields to address different aspects of biodiversity loss, including genetics and sociology. I used genetic approaches to assess the conservation status of western bumble bees, a bumble bee species of conservation concern.

The western bumble bee is a bumble bee species that ranges from Alaska to New Mexico and as far east as Wyoming and Colorado. This species is disappearing in some places. It may soon be listed as endangered in the United States and is already listed as endangered in parts …


Redefining Nba Basketball Positions Through Visualization And Mega-Cluster Analysis, Alexander L. Hedquist Aug 2022

Redefining Nba Basketball Positions Through Visualization And Mega-Cluster Analysis, Alexander L. Hedquist

All Graduate Theses and Dissertations

Basketball players have historically been classified based on one of five positions, namely Point Guards, Shooting Guards, Small Forwards, and Centers. While grouping players into these five categories may provide general descriptions of their perceived role, these standard positions fall short of describing players based on their true abilities and performance. This MS thesis proposes a method to group players of the National Basketball Association (NBA) from the past 20 seasons into more meaningful and specific player positions. We systematically group these players into nine distinct categories, and we draw from a vast array of visualization tools, techniques, and software …


An Introduction To Combinatorics Via Cayley's Theorem, Jaylee Willis Aug 2022

An Introduction To Combinatorics Via Cayley's Theorem, Jaylee Willis

All Graduate Theses and Dissertations

In this paper, we explore some of the methods that are often used to solve combinatorial problems by proving Cayley’s theorem on trees in multiple ways. The intended audience of this paper is undergraduate and graduate mathematics students with little to no experience in combinatorics. This paper could also be used as a supplementary text for an undergraduate combinatorics course.


The Effect Of Species Choice, Seed Mix Composition, And Microtopography On Native Plant Restoration In Great Salt Lake Wetlands, Coryna Hebert Aug 2022

The Effect Of Species Choice, Seed Mix Composition, And Microtopography On Native Plant Restoration In Great Salt Lake Wetlands, Coryna Hebert

All Graduate Theses and Dissertations

Wetlands are important ecosystems that improve water quality, prevent floods, and provide wildlife habitat. As such, restoring native plants that promote wetland health is a high priority for land managers. However, there are many challenges to the restoration of native plants. In our study system (Great Salt Lake wetlands), many areas are invaded by the European grass, Phragmites australis. Phragmites grows in dense stands and displaces native plants. The reduction of native plant communities in Great Salt Lake wetlands is a major concern because these ecosystems provide habitat for millions of native birds. Managers have made successful efforts to …


Quantification Of Hydrologic Response To Forest Disturbance In Western U.S. Watersheds, Sara A. Goeking Aug 2022

Quantification Of Hydrologic Response To Forest Disturbance In Western U.S. Watersheds, Sara A. Goeking

All Graduate Theses and Dissertations

Forested watersheds produce more than half of the water supply in the United States. Forests affect how precipitation is partitioned into available water versus evapotranspiration. This dissertation investigated how water yield and snowpack responded to forest disturbance following recent disturbances in western U.S. forests during the period 2000-2019.

Chapter 2 systematically reviewed 78 recent studies that examined how water yield or snowpack changed after forest disturbances. Water yield and snowpack often increased after disturbance, but decreased in some circumstances. Decreased water yield was most likely to occur following disturbances that did not remove the entire forest canopy. It was also …


Dynamic System Discovery With Recursive Physics-Informed Neural Networks, Jarrod Mau Aug 2022

Dynamic System Discovery With Recursive Physics-Informed Neural Networks, Jarrod Mau

All Graduate Theses and Dissertations

This thesis presents a novel method, recursive Physics informed neural network, to learn the right hand side of differential equations. The neural network takes in data, then trains, and then acts as a proxy for the differential equation which can be used for modeling. We show the theoretical superiority of the recursive approach. We also use computer simulations to demonstrate the proved properties.