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Full-Text Articles in Physical Sciences and Mathematics

A Classification Of Tensors In Ecsk Theory, Joshua James Leiter May 2023

A Classification Of Tensors In Ecsk Theory, Joshua James Leiter

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

You might have heard of Einstein’s theory of General relativity (GR): it is the one where mass and energy curve the fabric of spacetime to create gravity. This is the major theory which allows communication through satellites and our GPS to work too! Wormholes have interested me, but there are some issues about forming them in GR. Interestingly enough, elementary particles are also characterized by their spin in the standard model. However, intrinsic spin is nowhere geometrically coupled to the geometry of spacetime in Einstein’s theory. Later, Élie Cartan, Dennis Sciama, and Tom Kibble all flushed out adding different aspects …


Deep Learning With Attention Mechanisms In Breast Ultrasound Image Segmentation And Classification, Meng Xu May 2023

Deep Learning With Attention Mechanisms In Breast Ultrasound Image Segmentation And Classification, Meng Xu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Breast cancer is a great threat to women’s health. Breast ultrasound (BUS) imaging is commonly used in the early detection of breast cancer as a portable, valuable, and widely available diagnosis tool. Automated BUS image analysis can assist radiologists in making accurate and fast decisions. Generally, automated BUS image analysis includes BUS image segmentation and classification. BUS image segmentation automatically extracts tumor regions from a BUS image. BUS image classification automatically classifies breast tumors into benign or malignant categories. Multi-task learning accomplishes segmentation and classification simultaneously, which makes it more appealing and practical than an either individual task. Deep neural …


Cross-Boundary Stewardship In Protected Area Centered Ecosystems: Perceptions Of Success And Characteristics Of Cooperative Engagement, Ryan D. Tarver May 2023

Cross-Boundary Stewardship In Protected Area Centered Ecosystems: Perceptions Of Success And Characteristics Of Cooperative Engagement, Ryan D. Tarver

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The legal boundaries of protected areas, such as national parks are established and enforced by humans. Therefore, jurisdictional boundaries are ultimately have human meaning but not necessarily ecological relevance as natural phenomena such as watersheds and wildlife habitat often extend beyond a jurisdictional boundary. When considering the extent of natural system, we find that protected areas only make up part of a given ecosystem. The result is a large expanse of lands that fall under a various ownership types that include both publicly and privately designated tracts of land. This presents a management challenge when attempting to manage at the …


Evapotranspiration And Energy Balance Of Irrigated Urban Turfgrass, Matthew D. Miksch May 2023

Evapotranspiration And Energy Balance Of Irrigated Urban Turfgrass, Matthew D. Miksch

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Water usage for irrigation is a big consumer of water resources in urban areas in Utah and other parts of the Intermountain Region of the Western United States. As populations continue to increase in these states, it is important to understand how much water is being used by urban landscapes in order to plan and manage future water resources. Evapotranspiration (ET), or the amount of water leaving a surface over a certain timeframe due to both transpiration from plants and evaporation from the soil, is a key variable in understanding how much water urban landscapes are really using to grow …


Getting The Dirt On Phosphorus Pollution In Mountain Lakes: Are Rising Soil Temperatures Contributing To Eutrophication In Mountain Watersheds?, Gordon O. Gianniny May 2023

Getting The Dirt On Phosphorus Pollution In Mountain Lakes: Are Rising Soil Temperatures Contributing To Eutrophication In Mountain Watersheds?, Gordon O. Gianniny

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Mountain watersheds provide a critical supply of clean water to millions of people around the world. In recent years, evidence of a concerning trend has emerged in these watersheds: rising phosphorus (P) concentrations. P often acts as the limiting nutrient in mountain lake ecosystems, so increasing P availability in mountain lakes and streams has the potential to drastically increase algal growth in these systems. In extreme cases, increasing mountain lake P concentrations may even cause harmful algal blooms that degrade downstream water quality. While the implications of rising P concentrations in mountain lakes are serious, the cause driving this widespread …


Examining Political Discourse On Online 8kun And Reddit Forums, Braden Mindrum May 2023

Examining Political Discourse On Online 8kun And Reddit Forums, Braden Mindrum

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A recent example of political violence in the United States was that of the January 6, 2021, Capitol attack in connection with the certification of Joseph R. Biden’s victory over Donald J. Trump in the 2020 US presidential election. This thesis analyzes the events of January 6, 2021, through the lens of social media discourse. This thesis presents a workflow that acquired over 5 million 8kun and Reddit posts from various apolitical and political forums in the three months preceding and following the Capitol attack on January 6, 2021. Techniques from text analysis are then used to group forums according …


Coding Bootcamps - Perceptions And Outcomes, Logan L. Hendricks May 2023

Coding Bootcamps - Perceptions And Outcomes, Logan L. Hendricks

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis is focused on gathering, aggregating and analysing data related to software development coding bootcamps. It comprises of three major research initiatives: A coding bootcamp outcomes meta-analysis, a study on perspectives regarding white-label coding bootcamps, and the data analysis of a survey gathering long-term outcomes of coding bootcamp and certificate program graduates.

The first study aggregates graduate outcome data from the three main organizations that review coding bootcamp outcomes: CourseReport.com, SwitchUp.com and the Council on Integrity in Results Reporting (CIRR). The purpose of this meta-review is to establish a baseline dataset which is immediately utilized in my further research. …


Adversarial Swarming: A Groundwork For Multi-Drone Independent Interception Exercises Through Ma-Poca In Unity, Johnathan D. Kunz May 2023

Adversarial Swarming: A Groundwork For Multi-Drone Independent Interception Exercises Through Ma-Poca In Unity, Johnathan D. Kunz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As drones become more popular and easier to use, air spaces are becoming more congested. Airports, hospitals, and similar structures require controlled, safe airspaces and drones are increasingly a threat. Locally controlled airspace requires efficient removal of airborne threats to continue sensitive operations. Many methods have been investigated for removing drones from contested airspace. Generally these methods involve ground-based signal disruption, physical contact, or drone interception of a single intruder. In this work we present a drone interception model with a low-cost, low-capability group of short-range drones intercepting an incoming drone.


Examining Model Complexity's Effects When Predicting Continuous Measures From Ordinal Labels, Mckade S. Thomas May 2023

Examining Model Complexity's Effects When Predicting Continuous Measures From Ordinal Labels, Mckade S. Thomas

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Many real world problems require the prediction of ordinal variables where the values are a set of categories with an ordering to them. However, in many of these cases the categorical nature of the ordinal data is not a desirable outcome. As such, regression models treat ordinal variables as continuous and do not bind their predictions to discrete categories. Prior research has found that these models are capable of learning useful information between the discrete levels of the ordinal labels they are trained on, but complex models may learn ordinal labels too closely, missing the information between levels. In this …


A Generative Neural Network For Discovering Near Optimaldynamic Inductive Power Transfer Systems, Md Shain Shahid Chowdhury Oni May 2023

A Generative Neural Network For Discovering Near Optimaldynamic Inductive Power Transfer Systems, Md Shain Shahid Chowdhury Oni

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

An urgent need is to electrify transportation to lower carbon emissions into the atmosphere. Wireless charging makes electrical vehicles (EVs) more convenient and cheaper because energy is transferred to the vehicle without the need to plug it in. Dynamic wireless charging is particularly interesting, where the vehicle does not need to stop to receive the energy. This technology requires the EV and the roadway to include coils of wire, where the roadway coil is energized as the vehicle passes over it to induce an electrical current in the EV coil through electromagnetic induction. However, the problem of designing the two …


Opportunities And Challenges For Cooperative Extension Becoming A Major Actor In Climate Change Mitigation And Adaptation, Dakoeta R. Pinto May 2023

Opportunities And Challenges For Cooperative Extension Becoming A Major Actor In Climate Change Mitigation And Adaptation, Dakoeta R. Pinto

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Addressing climate change in the United States is an increasingly complex issue that requires social and technological changes throughout the country, which the Cooperative Extension System (Extension) can influence. Based at land-grant universities, their goals are to bring relevant science and innovation to the people of the United States. For a successful low-carbon transition, there are certain elements of society that must be influenced by innovators like Extension. Extension’s historical roots in agriculture prevail today with most of their programming focusing on this sector. However, there is a movement within Extension to expand their programmatic efforts to address more contemporary …


The Concept Of Multicenter Bonds In Chemistry And Materials Science, Nikolay V. Tkachenko May 2023

The Concept Of Multicenter Bonds In Chemistry And Materials Science, Nikolay V. Tkachenko

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Chemical bonds are components of a universal and compact language of chemistry that was empirically developed before the modern concepts of quantum physics. This language explains how molecules and solids keep together. In particular, Lewis’s shared electron-pair bonding model may be considered the most successful and generally accepted theory of chemical bonding due to its simplicity and predictive power. However, there is an entire world of chemical species where the classical Lewis bonding language fails to describe the bonding pattern adequately. Those cases include but are not limited to compounds with a significant electron delocalization (where electron density spread on …


Regeneration Of Quaking Aspen And Understory Vegetation Change After Fire Risk Reduction Treatment, Allison M. Trudgeon May 2023

Regeneration Of Quaking Aspen And Understory Vegetation Change After Fire Risk Reduction Treatment, Allison M. Trudgeon

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Quaking aspen (Populus tremuloides Michx.) is a keystone species that, when coexisting with conifers (i.e., seral aspen), often undergoes stand-replacing disturbances to sustain long term vigor. Historically, mixed-to-high severity fire reduced fuels and regenerated aspen, but such disturbances have become less common in recent decades. This has often led to high fuel loading, and many seral aspen stands are at now risk of an unpredictable, high-severity fire, posing a threat to development in the wildland-urban-interface. The lack of a commercial market for aspen, and the risk of conducting prescribed fire, means there are few alternate management options. This has …


Practical Improvements For Pivot And Surface Irrigation, Jonathan A. Holt May 2023

Practical Improvements For Pivot And Surface Irrigation, Jonathan A. Holt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Irrigation is critical to meeting global food and fiber demands. Optimizing agricultural irrigation may help sustain production levels, while reducing its demand for water. This research evaluated precision sprinklers and drip irrigation for pivots, five pivot track mitigation tools, three scientific irrigation scheduling (SIS) methods, sensors for surface irrigation cutoff, and automating surface systems to implement surge irrigation. With pivots and surface irrigation being the most common methods for irrigation in the West, small improvements from these tools could result in significant water savings.

Low energy precision application (LEPA) sprinklers and mobile drip irrigation (MDI) were tested on two pivots. …


A Frobenius-Schur Extension For Real Projective Representation, Levi Gagnon‐Ririe May 2023

A Frobenius-Schur Extension For Real Projective Representation, Levi Gagnon‐Ririe

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Many problems in physics have explicit mathematical descriptions. This thesis aims to provide the mathematical tools for a particular problem in physics, that of Quantum Mechanical symmetries. In essence, we extend the known mathematics to a more general setting and provide a wider view of Real projective representation theory. The work done in this thesis contributes to the subfield of mathematics known as representation theory and to the subfield of physics concerned with time reversal symmetry.


From Mountain Streams To Urban Rivers: An Assessment Of Microplastic Sources And Characteristics, Macy Gustavus May 2023

From Mountain Streams To Urban Rivers: An Assessment Of Microplastic Sources And Characteristics, Macy Gustavus

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Plastic products are produced and discarded at an alarming rate. Bottles, bags, toys, and clothing break down into tiny plastic pieces called microplastics, ranging in size from an eraser on the top of a pencil to smaller in size than a red blood cell. Microplastics are becoming so common in the environment that they travel in the atmosphere, rivers, and ocean currents in ways that are similar to other types of Earth Systems Cycles (i.e., the water cycle). In this study, we explored microplastic sources and sinks in a freshwater river system and how seasonal changes in discharge affect how …


Algorithms For Unit-Disk Graphs And Related Problems, Yiming Zhao May 2023

Algorithms For Unit-Disk Graphs And Related Problems, Yiming Zhao

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In this dissertation, we study algorithms for several problems on unit-disk graphs and related problems. The unit-disk graph can be viewed as an intersection graph of a set of congruent disks. Unit-disk graphs have been extensively studied due to many of their applications, e.g., modeling the topology of wireless sensor networks. Lots of problems on unit-disk graphs have been considered in the literature, such as shortest paths, clique, independent set, distance oracle, diameter, etc. Specifically, we study the following problems in this dissertation: L1 shortest paths in unit-disk graphs, reverse shortest paths in unit-disk graphs, minimum bottleneck moving spanning …


Recreational Fishing Participation In Utah: Comparing Active And Non-Active Angler Constraint Perceptions With The Use Of License Purchase Data, Will Rempel May 2023

Recreational Fishing Participation In Utah: Comparing Active And Non-Active Angler Constraint Perceptions With The Use Of License Purchase Data, Will Rempel

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As a leisure activity, recreational fishing provides numerous social, physical, and psychological benefits to its participants. It can also provide socioeconomic opportunities to specific communities, and as an outdoor activity can create support for natural fisheries resources and public lands. License and equipment taxes are also important funding mechanisms for state wildlife managers. Though fishing participation as a percentage of the population has overall decreased in the last century, there is a recent increase in fishing participation. However, participation dynamics result in a shifting cycle of entries, departures, and re-entries to the sport. In an effort to maintain participation and …


Generative Neural Network Approach To Designing And Optimizing Dynamic Inductive Power Transfer Systems, Andrew Pond Curtis May 2023

Generative Neural Network Approach To Designing And Optimizing Dynamic Inductive Power Transfer Systems, Andrew Pond Curtis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Electric vehicles (EVs) offer many improvements over traditional combustion engines including increasing efficiency, while decreasing cost of operation and emissions. There is a need for the development of cheap and efficient charging systems for the future success of EVs. Most EVs currently utilize static plug-in charging systems. An alternative charging method of significant interest is dynamic inductive power transfer systems (DIPT). These systems utilize two coils, one placed in the vehicle and one in the roadway to wirelessly charge the vehicle as it passes over. This method removes the current limitations on EVs where they must stop and statically charge …


Daytime Versus Nighttime Sprinkler Irrigation Of Two Urban Crops In A Semi-Arid Climate At High-Elevation, Samikshya Pyakurel May 2023

Daytime Versus Nighttime Sprinkler Irrigation Of Two Urban Crops In A Semi-Arid Climate At High-Elevation, Samikshya Pyakurel

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nighttime irrigation scheduling is a longstanding water conservation approach to reduce evaporative losses in Utah's semi-arid, urban landscapes. However, residential demand now exceeds system capacity, and the efficiency of the practice has come under question. Therefore, the objectives of this study include: 1) quantify whether a water savings exists between day and night irrigation with a water balance and energy balance approach, and 2) analyze microclimate and crop quality effects to determine any changes to evaporative demand or plant stress by irrigation timing. In 2019, we established 12 field plots in North Logan, UT (41.77° N, -111.81° W, 1380 m …


Impacts Of Irrigation Technology, Irrigation Rate, And Drought-Tolerant Genetics On Silage Corn Production, Tina Sullivan, Matt Yost, Dakota Boren, Earl Creech, Boyd Kitchen, Randall Violett, Burdette Barker Apr 2023

Impacts Of Irrigation Technology, Irrigation Rate, And Drought-Tolerant Genetics On Silage Corn Production, Tina Sullivan, Matt Yost, Dakota Boren, Earl Creech, Boyd Kitchen, Randall Violett, Burdette Barker

Plants, Soils and Climate Student Research

Many studies have examined individual water-saving management practices for corn (Zea mays L.), but few studies have looked at how combinations of practices might further enhance water optimization. The research objectives of this paper were to evaluate the impact of irrigation technology, irrigation rate, and crop genetics, as well as their interactions, on silage corn yield and forage quality. Trials were conducted in three Utah locations from 2019 through 2021. The results from five site-years indicated that the best water optimization practices varied by site-year. Low-elevation sprinklers commonly applied water more efficiently, with four of the five site-years having …


High Frequency Radio Communication, Tyler Larsen Apr 2023

High Frequency Radio Communication, Tyler Larsen

Physics Capstone Projects

High frequency radio communication has been the most reliable form of communication for many decades. Over that period, we have learned and experienced times of enhanced signals along with complete radio blackouts. The purpose of this research is to collect and analyze radio signal data to see the evidence of various reasons as to why these phenomena occur. A radio antenna was set up at USU campus to retrieve the signals from beacon networks across the globe that transmit signals every 15 minutes. By tracking a few of these signals we can locate the times of discrepancies in the signals …


The Kp Index And Behavior Of Quiet Periods, Collette Walbeck Apr 2023

The Kp Index And Behavior Of Quiet Periods, Collette Walbeck

Physics Capstone Projects

The Kp-index quantifies the electromagnetic effects in the Earth’s atmosphere and is used in a variety of scientific fields. Higher Kp values tend to be the focus in these fields as they relate to high solar activity and geomagnetic storms. This study aimed to examine the significance, if any, of lower Kp indices. A simple data analysis was performed on continuous sequences of low Kp values, deemed Quiet Periods. Both the daily average of the values and the full set of Kp data were used. A decaying exponential relationship was discovered between the length of these periods and their frequencies …


Effectiveness Of Multilayer Graded-Z Forms Of Radiation Shielding, Brinley Packer Apr 2023

Effectiveness Of Multilayer Graded-Z Forms Of Radiation Shielding, Brinley Packer

Physics Capstone Projects

This study explored how different forms of radiation shielding were more or less effective than standard single-layer shielding. Beta and gamma radiation sources were used and measured using a Geiger counter to determine how well the various forms of shielding protect against the radiation. The shielding effectiveness of standard homogeneous materials (e.g., graphite, carbon/epoxy composites, aluminum, and lead) of various thicknesses for different radiation sources was measured to provide standards for comparison. Once a basis of effective shielding was established, the study can go into greater depth into how to use shielding materials to be more effective, to better shield …


For The Dissertation: A Classification Of Tensors In Ecsk Theory, Joshua James Leiter, Charles G. Torre Apr 2023

For The Dissertation: A Classification Of Tensors In Ecsk Theory, Joshua James Leiter, Charles G. Torre

Physics Student Research

This dissertation presents a Petrov/Plebanski/Segre/Algebraic (PPSA) classification scheme for both the curvature and torsion tensors in Einstein-Cartan-Sciama-Kibble theory (ECSK); additionally the work includes a software package in Maple with computational and PPSA classification tools. Six different solutions are classified using the new software tools developed. We also present a new boundary term for ECSK-NMC scalar theory to ensure Dirichlet boundary conditions. New work completed includes the decomposition of an arbitrary 4th rank tensor under SO (p, q), equivalent SL (2, C) irreducible spinor decompositions of arbitrary 3rd and 4th rank tensors. We provide new proofs that the corresponding spinors are …


Rethinking Integrated Computer Science Instruction: A Cross-Context And Expansive Approach In Elementary Classrooms, Umar Shehzad, Jody E. Clarke-Midura, Kimberly Beck, Jessica F. Shumway, Mimi M. Recker Apr 2023

Rethinking Integrated Computer Science Instruction: A Cross-Context And Expansive Approach In Elementary Classrooms, Umar Shehzad, Jody E. Clarke-Midura, Kimberly Beck, Jessica F. Shumway, Mimi M. Recker

Publications

This study examines how a rural-serving school district aimed to provide elementary level computer science (CS) by offering instruction during students’ computer lab, a class taught by paraprofessional educators with limited background in computing. As part of a research practice partnership, cross-context mathematics and CS lessons were co-designed to expansively frame and highlight connections across – as opposed to integration within – the two subjects. Findings indicate that the paraprofessionals teaching the lessons generally reported positive experiences and understanding of content; however, those less comfortable with the content reported lower student interest. Further, most students who engaged with the lessons …


I-Optimal Or G-Optimal: Do We Have To Choose?, Stephen J. Walsh, Lu Lu, Christine M. Anderson-Cook Apr 2023

I-Optimal Or G-Optimal: Do We Have To Choose?, Stephen J. Walsh, Lu Lu, Christine M. Anderson-Cook

Mathematics and Statistics Faculty Publications

When optimizing an experimental design for good prediction performance based on an assumed second order response surface model, it is common to focus on a single optimality criterion, either G-optimality, for best worst-case prediction precision, or I-optimality, for best average prediction precision. In this article, we illustrate how using particle swarm optimization to construct a Pareto front of non-dominated designs that balance these two criteria yields some highly desirable results. In most scenarios, there are designs that simultaneously perform well for both criteria. Seeing alternative designs that vary how they balance the performance of G- and I …


Using Particle Swarm Optimization To Generate Optimal Experimental Designs With Replication Structures, Thomsen Bolton Apr 2023

Using Particle Swarm Optimization To Generate Optimal Experimental Designs With Replication Structures, Thomsen Bolton

Student Research Symposium

The modern dominant approach to planning experiments in industrial engineering and manufacturing is optimal design. This is a popular design paradigm because it 1) requires specification of an optimality criterion which incorporates practical objectives as definition of a design with high quality and 2) yields a design via high-dimensional optimization that gives the researcher ‘the most bang for the buck’ for a fixed sample/experimental run size. We aim to adapt the state-of-the-art meta-heuristic optimization algorithm, the Particle Swarm Optimization (PSO), to generating optimal designs with user-specified replication structure. Recently, PSO has been demonstrated to be highly effective at generating candidate …


Generating Optimal Space-Filling Designs With Particle Swarm Optimization, Rebekah Scott Apr 2023

Generating Optimal Space-Filling Designs With Particle Swarm Optimization, Rebekah Scott

Student Research Symposium

In 1935, Ronald Fisher published The Design of Experiments, establishing classical designs for various types of experiments. With the rise of computing power came optimal design, where statisticians can better customize designs according to the needs of the researchers running the experiment. This research focuses on generating optimal MaxMin space-filling designs with particle swarm optimization using various distance metrics (Manhattan, Euclidean, etc). Interestingly, changing the distance metric in the objective function had a minimal effect on the design, except for Aitchison geometry on the simplex. Space-filling designs are optimal for supporting high-order models with only a small sacrifice in prediction …


A Taste Of Gluten-Free Italy: Substituting The Structural Agent In Fettuccine, Olivia Purles, Madison Cavender, Emeline Manser Apr 2023

A Taste Of Gluten-Free Italy: Substituting The Structural Agent In Fettuccine, Olivia Purles, Madison Cavender, Emeline Manser

Student Research Symposium

The structural ingredient of pasta was varied in an attempt to identify a suitable and desirable gluten-free fettuccine pasta option. The flours that were used were almond flour, Bob’s TM Red Mill Gluten Free 1 to 1 Baking Flour, cricket flour, potato flour, and cornstarch, with all-purpose flour serving as the control. The objective tests that were performed were a noodle density test, and a water absorption test. Once the various noodles were made, they were presented to a consumer panel and various sensory evaluations were performed to determine the acceptability of appearance, texture, and flavor in fettuccine noodles. Bob’s …