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All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

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Laboratory Scale Anaerobic Reactors For Bioenergy From Wastes: Materials, Mathematical Models, And Stoichiometry, Yehor Pererva Dec 2020

Laboratory Scale Anaerobic Reactors For Bioenergy From Wastes: Materials, Mathematical Models, And Stoichiometry, Yehor Pererva

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Anaerobic processes are being explored for the production of bioenergy in the form of biomethane and biohydrogen in a "waste-to-value" approach that considers wastes as a resource. Laboratory scale Biomethane potential (BMP) tests and Up-Flow Anaerobic Sludge Blanket (UASB) reactors can be used to indicate the potential recovery of bioenergy from industry wastes. The goals of this research were to: (1) conduct a critical review of models for determining biomethane potential, (2) develop a theoretical relationship for stoichiometry for biomethane and biohydrogen from wastes, and (3) develop key design aspects for geometry and infrastructure, including gas-liquid-solid separation in laboratory UASB …


Applied Species Delimitation In Microbial Taxa And Plants, Austin C. Koontz Dec 2020

Applied Species Delimitation In Microbial Taxa And Plants, Austin C. Koontz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Species are a fundamental concept in biology, and many subdisciplines in biology utilize species in aspects of theory and in the communication of results. Given the centrality of species in biological science, it can seem surprising that there is no universal definition amongst biologists of what, strictly speaking, a species is. In fact, there are, by some estimates, over 20 different "species concepts", and this lack of a consensus is termed "the species problem". This problem has theoretical underpinnings, but has become more relevant as advances in sequencing technologies over the past two decades have allowed researchers to probe the …


Perceptions Of Disabilities Among Native Americans Within The State Of Utah, Erica Ficklin Dec 2020

Perceptions Of Disabilities Among Native Americans Within The State Of Utah, Erica Ficklin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Native Americans are diagnosed with disabilities at a significantly higher rate than the general American population. Due to cultural differences, other factors are likely impacting this difference in diagnosis rates. One possible factor is that Native Americans may have a different definition for ‘disability’ than the general American population. This study aimed to identify whether there is a difference in the definition for ‘disability’ and to learn about the current services available and what changes should be made to better serve Native Americans with disabilities. Native American participants were asked to share their experiences and thoughts about disabilities in sharing …


A Thermochronometric, Microtextural, And Numerical Modeling Approach To Deciphering The Rock Record Of Deformation Processes In The Wasatch And Denali Fault Zones, Robert G. Mcdermott Dec 2020

A Thermochronometric, Microtextural, And Numerical Modeling Approach To Deciphering The Rock Record Of Deformation Processes In The Wasatch And Denali Fault Zones, Robert G. Mcdermott

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Fault zones are the primary features that accommodate movement of Earth’s crust, resulting in the formation of mountain belts and damaging earthquakes. Rocks modified by faulting and brought to Earth’s surface by erosion are archives of the mechanical processes involved in earthquakes and(or) aseismic creep. Thermochronometry is a radioisotopic dating system primarily sensitive to temperature and offers a means to constrain dates and rates of thermal processes. Hematite is common in fault zones, amenable to (U-Th)/He (He) thermochronometry, and exhibits distinct microtextures diagnostic of fault zone mechanics. I apply hematite He thermochronometry and microtextural analyses with a suite of other …


A Deep Dive Into Natural Swimming Pool Filtration: Living Walls As Technical Wetland Filters, Anna Farb Dec 2020

A Deep Dive Into Natural Swimming Pool Filtration: Living Walls As Technical Wetland Filters, Anna Farb

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Vertical gardens such as living walls can filter air and water, in addition to cooling buildings, reducing noise, increasing urban biodiversity, providing food, and enhancing well-being. Natural swimming pools (NSPs) are an ecologically sound alternative to chemically treated pools, but they have not reached their potential in the U.S. We investigated whether a living wall could be integrated into an NSP system for water filtration purposes, given that the vertical filter would have to produce excellent water quality for human swimmers. This could be a novel landscape design, particularly in the cases of steep contours, urbanized sites with limited space, …


Pre-Eruptive Evolution Of Izu-Bonin Boninite Melts: Mixing, Cooling, And Crystallization, Jesse L. Scholpp Dec 2020

Pre-Eruptive Evolution Of Izu-Bonin Boninite Melts: Mixing, Cooling, And Crystallization, Jesse L. Scholpp

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Subduction is the geologic process in which one tectonic plate moves beneath another as it sinks into the Earth’s mantle. Subduction initiation in the Izu-Bonin Marianas system is the result of a gravitational failure during which one tectonic plate (the Pacific plate) spontaneously sinks beneath another (the Philippne Sea plate). Fluids released by the sinking plate that caused the overlying mantle to melt by reducing its meltimg temperature, forming the Izu-Bonin Mariana island arc system.

The resulting melts initially have the chemical compositions that are rich in silica and magnesia, and highly depleted in other elements, refered to a boninite …


Analytic Guidance Strategies For Passively Safe Rendezvous And Proximity Operations, Simon Shuster Dec 2020

Analytic Guidance Strategies For Passively Safe Rendezvous And Proximity Operations, Simon Shuster

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A safety ellipse is a type of relative motion trajectory that is commonly used for unmanned rendezvous and proximity operations. As the name suggests, safety ellipses are passively safe relative motion trajectories, which means that their natural motion inherently maintains a low collision risk. The focus of this dissertation is the derivation, analysis, and application of guidance strategies that reconfigure, establish, and exit a safety ellipse. The guidance strategies consist of a set of ∆v vectors and impulse times, all written in closed form. Through applications of optimal control theory and parameter optimization, it is shown that these maneuver …


Transfer Of Learning For K-12 Stem Teachers: From The Gear Up Engineering Camp Professional Learning Experience To The Classroom, Ryan F. Barlow Dec 2020

Transfer Of Learning For K-12 Stem Teachers: From The Gear Up Engineering Camp Professional Learning Experience To The Classroom, Ryan F. Barlow

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Because of the new Utah Science with Engineering Education (SEEd) standards, which are based on the Next Generation Science Standards (NGSS), Utah science teachers in K-12 schools are now being asked to incorporate engineering into their science classes. Many science teachers in the State of Utah do not have a background in engineering and have not received training in how to incorporate engineering into their classes. To help remedy this problem, six STEM teachers from the State of Utah, and one STEM teacher from Nevada, came to the campus of Utah State University in July 2019 to participate with a …


Deep Q Learning Applied To Stock Trading, Agnibh Dasgupta Dec 2020

Deep Q Learning Applied To Stock Trading, Agnibh Dasgupta

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Developing a strategy for stock trading is a vital task for investors. However, it is challenging to obtain an optimal strategy, given the complex and dynamic nature of the stock market. This thesis aims to explore the applications of Reinforcement Learning with the goal of maximizing returns from market investment, keeping in mind the human aspect of trading by utilizing stock prices represented as candlestick graphs. Furthermore, the algorithm studies public interest patterns in form of graphs extracted from Google Trends to make predictions. Deep Q learning has been used to train an agent based on fused images of stock …


Job Satisfaction And Employee Turnover Determinants In Fortune 50 Companies: Insights From Employee Reviews From Indeed.Com, Bishal Sainju Dec 2020

Job Satisfaction And Employee Turnover Determinants In Fortune 50 Companies: Insights From Employee Reviews From Indeed.Com, Bishal Sainju

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

We explored 682176 employee reviews of Fortune 50 companies from Indeed.com using topic discovery techniques like Latent Dirichlet Allocation (LDA) and Structural Topic Modeling (STM) to identify salient aspects in employee reviews and automatically infer latent topics that tend to drive employee satisfaction. We also studied how various satisfaction factors could be related to employee turnover. We discovered important topics in the reviews, including Management and Leadership, Advancement Opportunity, Pay and Benefits, Work-Life Balance, and Culture, which we compare to the five Job Descriptive Index (JDI) facets. Both LDA and STM discovered well-separated and distinguishable topics. We also …


Acquisition, Processing, And Analysis Of Video, Audio And Meteorological Data In Multi-Sensor Electronic Beehive Monitoring, Sarbajit Mukherjee Dec 2020

Acquisition, Processing, And Analysis Of Video, Audio And Meteorological Data In Multi-Sensor Electronic Beehive Monitoring, Sarbajit Mukherjee

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In recent years, a widespread decline has been seen in honey bee population and this is widely attributed to colony collapse disorder. Hence, it is of utmost importance that a system is designed to gather relevant information. This will allow for a deeper understanding of the possible reasons behind the above phenomenon to aid in the design of suitable countermeasures.

Electronic Beehive Monitoring is one such way of gathering critical information regarding a colony’s health and behavior without invasive beehive inspections. In this dissertation, we have presented an electronic beehive monitoring system called BeePi that can be placed on top …


Micro Grid Control Optimization With Load And Solar Prediction, Shaju Saha Dec 2020

Micro Grid Control Optimization With Load And Solar Prediction, Shaju Saha

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Using renewable energy can save money and keep the environment cleaner. Installing a solar PV system is a one-time cost but it can generate energy for a lifetime. Solar PV does not generate carbon emissions while producing power. This thesis evaluates the value of being able to make accurate predictions in the use of solar energy. It uses predicted solar power and load for a system and a battery to store the energy for future use and calculates the operating cost or profit in several designed conditions. Various factors like a different place, tuning the capacity of sources, changing buy/sell …


Systems Thinking In Engineering Design: Differences In Expert Vs. Novice And Relationship To Personality Traits, Yuzhen Luo Dec 2020

Systems Thinking In Engineering Design: Differences In Expert Vs. Novice And Relationship To Personality Traits, Yuzhen Luo

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Systems thinking is the ability to see the big picture and the related elements when designing, and how these relationships form the big picture. In engineering design, systems thinking is valuable to both industry, as well as engineering education. As such, it creates opportunities for researchers to better understand systems thinking of both professional engineers in industry, who are assumed to be the experts, and engineering students in higher education, who are assumed to be the novices. The purpose of this study was to compare and identify the differences between expert and novice systems thinking in engineering design. Additionally, the …


Automation Of Feature Selection And Generation Of Optimal Feature Subsets For Beehive Audio Sample Classification, Aditya Bhouraskar Dec 2020

Automation Of Feature Selection And Generation Of Optimal Feature Subsets For Beehive Audio Sample Classification, Aditya Bhouraskar

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The last couple of decades have witnessed an abnormal phenomenon of reduction in the bee population, this is a serious matter of concern as three out of four crops available globally have honey bee as their sole pollinator causing significant economic losses and an unbalance in the ecosystem. There have been many theories about the cause of bee colony collapses such as parasites, pesticides and poor nutrition however conclusive evidence of this phenomenon is yet to be identified.

Human inspection of beehives requires precision. It takes an experienced beekeeper to determine the health of a hive by the sounds generated …


Effects Of The Radiation Belt On The Plasmasphere Distribution, Stefan Thonnard Dec 2020

Effects Of The Radiation Belt On The Plasmasphere Distribution, Stefan Thonnard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study examines the interaction of plasma, ions and electrons created by Solar illumination in the Earth’s upper atmosphere, that travels along magnetic field lines filling the Plasmasphere, and the naturally occurring trapped particles known as the outer radiation belt. Although these two science disciplines have been largely worked independent of each other due the vast differences in the energy of the particles, recent satellite observations indicate a large population of particles with lower energy and greater mass also exist in the outer radiation belt. This study shows that during conditions of low solar output in an 11-year cycle, these …


Transient Thermal Modeling Of Bioprocessing Equipment, Cody M. Cummings Aug 2020

Transient Thermal Modeling Of Bioprocessing Equipment, Cody M. Cummings

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Bioprocessing is leveraging cells to produce high value, lifesaving products. Precise environmental control is needed to maintain integrity of the bioprocessing production process. Temperature control requires both appropriate equipment choice and correct control parameter selection. To aid in the equipment selection process, enable better understanding of equipment capacity, and enable optimization of control parameters, a transient thermal model of both heat transfer characteristics and control systems was created in silico.


Teaching Students To Communicate With The Precise Language Of Mathematics: A Focus On The Concept Of Function In Calculus Courses, Derrick S. Harkness Aug 2020

Teaching Students To Communicate With The Precise Language Of Mathematics: A Focus On The Concept Of Function In Calculus Courses, Derrick S. Harkness

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The use of precise language is one of the defining characteristics of mathematics that is often missing in mathematics classrooms. This lack of precision results in poorly constructed concepts that limit comprehension of essential mathematical definitions and notation. One important concept that frequently lacks the precision required by mathematics is the concept of function. Functions are foundational in the study undergraduate mathematics and are essential to other areas of modern mathematics. Because of its pivotal role, the concept of function is given particular attention in the three articles that comprise this study.

A unit on functions that focuses on using …


Storm-Time Equatorial Thermospheric Dynamics And Electrodynamics, Luis A. Navarro Dominguez Aug 2020

Storm-Time Equatorial Thermospheric Dynamics And Electrodynamics, Luis A. Navarro Dominguez

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

We present the first complete study of the dynamics of the equatorial upper atmosphere (180-350 km) during periods of strong magnetic activity driven by the Sun, which are generally referred as geomagnetic storms. These storms have the potential to considerably affect satellite-based communications and navigation systems among other severe technological challenges. We used large databases of two of the most important parameters at these altitudes, which are the velocities of the neutral and ionized gas (plasma) referred to as neutral winds and plasma drifts. These measurements were acquired in the Peruvian equatorial region by the Jicamarca radar and by a …


Boron In The Pariette Wetlands, Uinta Basin, Ut, Palak Vasudeva Aug 2020

Boron In The Pariette Wetlands, Uinta Basin, Ut, Palak Vasudeva

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Boron is a naturally occurring mineral in shale and coal beds formed in marine environments, as found in the Uinta Basin. Mining activity and the application of excess irrigation water on agricultural lands in the Pariette watershed lead to mobilization of B via surface run off. Water quality monitoring records from 2006- 2009 reported violations of Utah B standard for irrigation water 43-100% of the time, for water flowing through the Pariette Wetlands. This study aims to determine B distribution in abiotic (water, sediments) and biotic samples (macroinvertebrates, aquatic vegetation, fish, bird eggs), and to establish correlations between B concentrations …


Effect Of Plant Derived Tannins On Nitrogen And Carbon Cycling In Pasture Soils, Kathryn A. Slebodnik Aug 2020

Effect Of Plant Derived Tannins On Nitrogen And Carbon Cycling In Pasture Soils, Kathryn A. Slebodnik

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Pasture-finished beef has become increasingly popular, but nitrogen losses from these pastures are of concern. Legumes containing condensed tannins such as birdsfoot trefoil (Lotus corniculatus) and sainfoin (Onobrychis viciifolia) may serve as environmentally and economically viable alternative forages in pasture finishing systems while reducing soil nitrogen loss. The goal of this project was to understand how tannin type and concentration affects soil nitrogen cycling both in the lab and the field. This thesis: 1) compared the physical, chemical, and biological characteristics of soil samples obtained from grazed grass and tannin and non-tannin containing legume pastures, 2) …


Some Examples Of The Liouville Integrability Of The Banded Toda Flows, Zachary Youmans Aug 2020

Some Examples Of The Liouville Integrability Of The Banded Toda Flows, Zachary Youmans

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Toda lattice is a famous integrable system studied by Toda in the 1960s. One can study the Toda lattice using a matrix representation of the system. Previous results have shown that this matrix of dimension n with 1 band and n‚àí1 bands is Liouville integrable. In this paper, we lay the foundation for proving the general case of the Toda lattice, where we consider the matrix representation with dimension n and a partially filled lower triangular part. We call this the banded Toda flow. The main theorem is that the banded Toda flow up to dimension 10 is …


Indoor Source Localization Of Radio Frequency Transmitters Using Blind Channel Identification Techniques, Madison L. Rose Aug 2020

Indoor Source Localization Of Radio Frequency Transmitters Using Blind Channel Identification Techniques, Madison L. Rose

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Locating transmitters is a research area that is becoming increasingly relevant as technology advances. It is especially useful for determining the location of livestock, drones, keys, phones, tablets, etc. As a result of this push for locating devices, many algorithms have been developed to determine source locations. Most source location algorithms and techniques rely on a "line of sight", or a direct path between the source and the receivers to provide accurate results.

Indoor environments pose a challenge to locating transmitters due to the many surfaces that allow radio waves to interact (reflect, refract, and generally distort) with them. Because …


Soil Health Assessment On Arid Rangeland Soils Impacted By Oil And Gas Exploration, Development, And Extraction, Justin Allred Aug 2020

Soil Health Assessment On Arid Rangeland Soils Impacted By Oil And Gas Exploration, Development, And Extraction, Justin Allred

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Oil and gas well pad reclamation in arid environments such as in the Uinta Basin of Utah, presents unique challenges, including remote locations, limited water, and elevated soil salinity and sodicity. Successfully reclaimed Plugged and Abandoned (P&A) well pads should resemble the surrounding rangeland once fully reclaimed. Revegetation of native species is the primary indicator of successful reclamation, but the lack of water makes it challenging to re-seed native plants, while trying to prevent the encroachment of invasive plant species such as Bromus tectorum (cheatgrass), Salsola tragus (Russian thistle), and Halogeton glomeratus (halogeton). Could successful reclamation be reflective of good …


Optimization Of Aileron Spanwise Size And Shape To Minimize Induced Drag In Roll With Correlating Adverse Yaw, Joshua R. Brincklow Aug 2020

Optimization Of Aileron Spanwise Size And Shape To Minimize Induced Drag In Roll With Correlating Adverse Yaw, Joshua R. Brincklow

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Most modern aircraft make use of modifying the main wing in flight to begin a roll. In many cases, this is done with a discrete control surface known as an aileron. The lift, drag, and moments for the wing are affected in part by the location and size of the ailerons along the length of the wing. The lift, drag, and moments can be found using a lifting-line theory that considers the circulation in airflow from many small sections of the wing. To minimize the drag due to lift on the wing, the ailerons must be optimized for the best …


Visual Saliency Estimation And Its Applications, Fei Xu Aug 2020

Visual Saliency Estimation And Its Applications, Fei Xu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The human visual system can automatically emphasize some parts of the image and ignore the other parts when seeing an image or a scene. Visual Saliency Estimation (VSE) aims to imitate this functionality of the human visual system to estimate the degree of human attention attracted by different image regions and locate the salient object. The study of VSE will help us explore the way human visual systems extract objects from an image. It has wide applications, such as robot navigation, video surveillance, object tracking, self-driving, etc.

The current VSE approaches on natural images models generic visual stimuli based on …


A Bayesian Markov Chain Monte Carlo Approach To Uncertainty Quantification, Matthew Isaac Aug 2020

A Bayesian Markov Chain Monte Carlo Approach To Uncertainty Quantification, Matthew Isaac

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Uncertainty quantification (UQ) is a framework used frequently in engineering analyses to understand how uncertainty in system inputs lead to uncertainty in the system output. An instability is observed in a UQ method proposed by Roy and Oberkampf and a Bayesian Markov Chain Monte Carlo approach to UQ is offered as an alternative. The Bayesian approach allows analysts to incorporate information from various available sources including observed measurements and expert opinion and to update the analysis and results as more information becomes available. An illustrative engineering example is provided as a platform to demonstrate the Bayesian UQ approach and to …


A General Approach To Lifting-Line Theory, Applied To Wings With Sweep, Jackson T. Reid Aug 2020

A General Approach To Lifting-Line Theory, Applied To Wings With Sweep, Jackson T. Reid

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Lifting-line theory is one simple method of predicting the lift produced by a wing. The traditional implementation of lifting-line theory, developed in 1918, is limited to predicting the lift of traditional straight wings. In this work, lifting-line theory is extended to predict the lift produced by modern swept (or "v-shaped") wings by strategically handling the singularities inherent to the theory. The resulting formulation is shown to be both accurate and computationally inexpensive, when compared to experimental and higher-fidelity computational results, demonstrating the method's usefulness as an aerodynamic design tool. Because of the low computational cost and accuracy of the method …


Analyzing The Von Neumann Entropy Of Contact Networks, Thomas J. Brower Aug 2020

Analyzing The Von Neumann Entropy Of Contact Networks, Thomas J. Brower

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

When modeling the spread of disease, ecologists use ecological or contact networks to model how species interact with their environment and one another. The structure of these networks can vary widely depending on the study, where the nodes of a network can be defined as individuals, groups, or locations among other things. With this wide range of definition and with the difficulty of collecting samples, it is difficult to capture every factor of every population. Thus ecologists are limited to creating smaller networks that both fit their budget as well as what is reasonable within the population of interest. With …


Nitrogen Fertilizer Needs Of First-Year Small Grains Following Alfalfa, Collin Pound Aug 2020

Nitrogen Fertilizer Needs Of First-Year Small Grains Following Alfalfa, Collin Pound

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Wheat, barley, triticale, and oats, are small grains commonly grown as hay and grain following alfalfa in Utah and the Intermountain West, especially during drought years as they require less irrigation than corn. Several studies in many parts of the world have shown that first-year corn following alfalfa rarely needs nitrogen (N) fertilizer, yet relatively few have evaluated the N needs of small grains, especially small grains grown for hay. Objectives of this research were to determine whether N fertilizer is needed to economically optimize the yield and quality of first-year small grains following alfalfa, develop N guidelines, and whether …


Ecology And Economic Impact Of The Invasive Brown Marmorated Stink Bug (Hemiptera: Pentatomidae; Halyomorpha Halys) In The Utah Agricultural Landscape, Zachary R. Schumm Aug 2020

Ecology And Economic Impact Of The Invasive Brown Marmorated Stink Bug (Hemiptera: Pentatomidae; Halyomorpha Halys) In The Utah Agricultural Landscape, Zachary R. Schumm

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The brown marmorated stink bug (BMSB) is a major insect pest that causes economic loss to a diversity of U.S. fruit and vegetable crops, and invades homes and human structures, causing nuisance issues for homeowners. This destructive insect causes millions of dollars of crop damage annually, and is difficult to manage due to its resistance to some common insecticides. BMSB is a relatively new pest to Utah, and its biology and ecology is not well known in the high elevation, arid Intermountain West region. In Chapter II, I explored the potential impact of BMSB to tart cherry, an unstudied crop …