Digital Commons Network^™

Approaches, Techniques, And Tools For Identifying Important Code Changes To Help Code Reviewers, Maneesh M. Mohanavilasam

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Software development is a collaborative process where many developers come together and work on a project. To make things easy and manageable, software is developed on a version control system. A version control system is a centralized system which stores code and adds code from all other developers as an increment to the code base in the repository. Since multiple people work on the same code repository together, it is important to make sure that their contributions do not conflict with each other. It is important to maintain the quality and integrity of the repository. This is where the code …

Changing The World Through The Word: Developing Critical Consciousness Through Multicultural Children’S Literature With Critical Literacy In An Elementary Classroom, Hyekyoung Lee

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to explore how fifth graders develop critical consciousness regarding the self and the world through critical literacy approaches using multicultural children’s literature. I employed Lewison, Flint, and Van Sluys’ four dimensions of critical literacy. I used a qualitative case study to design, frame and conduct this study in order to collect data and examine students’ cultural patterns including values, beliefs, behaviors, and language that they enacted in the critical literacy practices. I collected data through classroom observations, semi-structured students and teacher interviews, informal conversation, researcher’s reflective journal entries and field notes, and student-made artifacts. …

Mechanistic Studies Of The Iron And Molybdenum Nitrogenases, Derek Harris

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As a basic building block in many biological molecules the element nitrogen (N) is essential for life. Dinitrogen (N2) is abundant in Earth’s atmosphere, but this form is biologically unavailable. To be biologically available N2 must undergo an energy demanding reduction reaction to the fixed form, ammonia (NH3). The industrial Haber-Bosch process, which accounts for approximately 50% of the worlds fixed nitrogen, uses energy from fossil fuels to achieve high pressures and temperatures to facilitate the reaction. The energy used by Haber-Bosch accounts for approximately 2% of the world’s annual supply. The remainder of fixed nitrogen is produced biologically by …

Novel Statistical Models For Quantitative Shape-Gene Association Selection, Xiaotian Dai

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Other research reported that genetic mechanism plays a major role in the development process of biological shapes. The primary goal of this dissertation is to develop novel statistical models to investigate the quantitative relationships between biological shapes and genetic variants. However, these problems can be extremely challenging to traditional statistical models for a number of reasons: 1) the biological phenotypes cannot be effectively represented by single-valued traits, while traditional regression only handles one dependent variable; 2) in real-life genetic data, the number of candidate genes to be investigated is extremely large, and the signal-to-noise ratio of candidate genes is expected …

Rancher Perceptions Of Ecosystem Services From Rangelands Of The Intermountain West, Elisabeth C. York

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Rangelands within the Great Basin are responsible for the provision of multiple resources that humans depend on for a variety of reasons. Ranchers in this region are dependent on public lands to remain economically viable in their cattle operations. As a majority of land in this region is publically owned, there are varying interests at play in what should and could be the focus of management. Ranchers are charged with implementing strategies aimed at conserving these landscapes and their motivations for what to manage may significantly influence resource provision from Intermountain West ecosystem.

In this study, I sought to understand …

Non-Methane Hydrocarbon Source Apportionment And Btex Risk Assessment Of Winter 2015 In Roosevelt, Utah, Jerimiah Lamb

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Non-Methane Hydrocarbons (NMHC) monitored in Roosevelt Utah including Benzene, Toluene, Ethylbenzene and Xylene (collectively known as BTEX) are associated with deleterious effects including cancer. This study was designed to assess the origin and effect of the toxicants and addressed two points: 1) Source identification using the USEPA’s Positive Matrix Factorization (PMF) and NOAA’s Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model and 2) A human health risk assessment based on ambient concentrations of BTEX collected at the Roosevelt site. Model fit indicated that the primary contributor to total NMHCs was local oil and gas operations and was supported by previous …

The Influence Of Varying Fiber Stacking Sequence On The Tensile, Impact, And Water Absorption Properties Of Unidirectional Flax/E-Glass Fiber Reinforced Epoxy Composite, Mohammed F. Al-Edhari

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis includes the study of the mechanical performance of two different types of fibers reinforced hybrid composites. Two kinds of fibers, natural fiber (flax) and synthetic fiber (E-glass), are used to reinforce epoxy resin. To evaluate the effective properties of the hybrid composites, a micromechanical analysis of the structure genome (SG) of a unidirectional fiber hybrid composites is performed using nite element analysis (FEA). Both fibers are assumed to be circular and packed in a hexagonal pattern. The effects of varying volume fractions and fiber locations, of the two fibers, on the elastic properties of the hybrid composites are …

Extracting And Visualizing Data From Mobile And Static Eye Trackers In R And Matlab, Chunyang Li

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Eye tracking is the process of measuring where people are looking at with an eye tracker device. Eye tracking has been used in many scientific fields, such as education, usability research, sports, psychology, and marketing. Eye tracking data are often obtained from a static eye tracker or are manually extracted from a mobile eye tracker. Visualization usually plays an important role in the analysis of eye tracking data. So far, there existed no software package that contains a whole collection of eye tracking data processing and visualization tools. In this dissertation, we review the eye tracking technology, the eye tracking …

Twentieth Century Channel Change Of The Green River In Canyonlands National Park, Utah, Alexander E. Walker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Since the early 20^th century, river channels of the Colorado River basin have narrowed, decreasing available riparian and aquatic habitat. Changes are considered to be the result of three major factors: wide-spread water development, increasing hydroclimate variability and the invasion of non-native tamarisk (Tamarix spp.), altering flow regime and sediment supply. Different studies have reached different conclusions about the relative roles of flow regime, sediment supply and tamarisk in causing narrowing.

I investigated channel change in the lower Green River within Canyonlands National Park to describe channel changes in the 20^th century and understand the roles …

Exact Approaches For Bias Detection And Avoidance With Small, Sparse, Or Correlated Categorical Data, Sarah E. Schwartz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Every day, traditional statistical methodology are used world wide to study a variety of topics and provides insight regarding countless subjects. Each technique is based on a distinct set of assumptions to ensure valid results. Additionally, many statistical approaches rely on large sample behavior and may collapse or degenerate in the presence of small, spare, or correlated data. This dissertation details several advancements to detect these conditions, avoid their consequences, and analyze data in a different way to yield trustworthy results.

One of the most commonly used modeling techniques for outcomes with only two possible categorical values (eg. live/die, pass/fail, …

Geological Characterization Of Precambrian Nonconformities: Implications For Injection-Induced Seismicity In The Midcontinent United States, Laura Cuccio

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The midcontinent United States, a region which typically does not experience many earthquakes, has experienced a significant increase in the number of earthquakes over the last decade. This increase in earthquake activity has been linked to wastewater injection, a process in which large volumes of wastewater from oil and gas extraction are injected into deep (2-3 km), high-permeability sedimentary rocks, near low-permeability Precambrian (>540-million-year-old) crystalline ‘basement’ rocks. The contact between these two rock types is referred to as the Precambrian nonconformity. Injection-induced earthquakes occur on or near basement-hosted faults due to an increase in pore fluid pressures, which implies …

Aerodynamic Centers Of Arbitrary Airfoils, Orrin Dean Pope

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The study of designing stable aircraft has been widespread and ongoing since the early days of Orville and Wilbur Wright and their famous Wright Flyer airplane. All aircraft as they fly through the air are subject to minor changes in the forces acting on them. The field of aircraft stability seeks to understand and predict how aircraft will respond to these changes in forces and to design aircraft such that when these forces change the aircraft remains stable. The mathematical equations used to predict aircraft stability rely on knowledge of the location of the aerodynamic center, the point through which …

The Investigation Of Gravity Waves In The Mesosphere / Lower Thermosphere And Their Effect On Sporadic Sodium Layer, Xuguang Cai

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Gravity waves in the atmosphere are the waves with gravity and buoyancy force as the restoring forces. Gravity waves will significantly impact the Mesosphere Lower / Thermosphere (MLT), and the breaking of gravity waves is the key factor to cause the cool summer and warm winter in the Mesopause region. Therefore, it is important for us to investigate gravity waves. In this dissertation, we mainly use USU Na lidar data to explore gravity waves in the MLT. The exploration is made up of two projects. One is the investigation of gravity wave breaking and the associated dynamic instability by USU …

Impacts Of Distributions And Trajectories On Navigation Uncertainty Using Line-Of-Sight Measurements To Known Landmarks In Gps-Denied Environments, Ryan D. Lamoreaux

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Unmanned vehicles are increasingly common in our world today. Self-driving ground vehicles and unmanned aerial vehicles (UAVs) such as quadcopters have become the fastest growing area of automated vehicles research. These systems use three main processes to autonomously travel from one location to another: guidance, navigation, and controls (GNC). Guidance refers to the process of determining a desired path of travel or trajectory, affecting velocities and orientations. Examples of guidance activities include path planning and obstacle avoidance. Effective guidance decisions require knowledge of one’s current location. Navigation systems typically answer questions such as: “Where am I? What is my orientation? …

Exploring And Describing The Spatial And Temporal Dynamics Of Medusahead In The Channeled Scablands Of Eastern Washington Using Remote Sensing Techniques, Timothy M. Bateman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Medusahead is a harmful weed that is invading public lands in the West. The invasion is a serious concern to the public because it can reduce forage for livestock and wildlife, increase fire frequency, alter important ecosystem cycles (like water), reduce recreational activities, and produce landscapes that are aesthetically unpleasing. Invasions can drive up costs that generally require taxpayer’s dollars. Medusahead seedlings typically spread to new areas by attaching itself to passing objects (e.g. vehicles, animals, clothing) where it can quickly begin to affect plants communities. To be effective, management plans need to be sustainable, informed, and considerate to invasion …

Stream Temperature Monitoring And Modeling To Inform Restoration: A Study Of Thermal Variability In The Western Us, Jessica R. Wood

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Water temperature is an important variable for aquatic ecosystems. Salmonid population numbers and distribution are heavily influenced by stream temperature, and there is growing concern about the health of salmonid populations with anticipated climate change. Managers are looking to efficiently evaluate options to maintain stream temperatures needed by salmonids. This study evaluated and compared stream temperature restoration alternatives in two streams with warm temperatures using stream temperature monitoring and modeling.

The first study identified pockets of cold water that are important to native fish species in Nevada’s Walker River. Comparison of monitoring results with existing basin-scale model outputs identified two …

Real Simple Lie Algebras: Cartan Subalgebras, Cayley Transforms, And Classification, Hannah M. Lewis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The differential geometry software package in Maple has the necessary tools and commands to automate the classification process for complex simple Lie algebras. The purpose of this thesis is to write the programs to complete the classification for real simple Lie algebras. This classification is difficult because the Cartan subalgebras are not all conjugate as they are in the complex case. For the process of the real classification, one must first identify a maximally noncompact Cartan subalgebra. The process of the Cayley transform is used to find this specific Cartan subalgebra. This Cartan subalgebra is used to find the simple …

Extensions And Improvements To Random Forests For Classification, Anna Quach

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The motivation of my dissertation is to improve two weaknesses of Random Forests. One, the failure to detect genetic interactions between two single nucleotide polymorphisms (SNPs) in higher dimensions when the interacting SNPs both have weak main effects and two, the difficulty of interpretation in comparison to parametric methods such as logistic regression, linear discriminant analysis, and linear regression.

We focus on detecting pairwise SNP interactions in genome case-control studies. We determine the best parameter settings to optimize the detection of SNP interactions and improve the efficiency of Random Forests and present an efficient filtering method. The filtering method is …

Application Of Machine Learning And Statistical Learning Methods For Prediction In A Large-Scale Vegetation Map, Carla M. Brookey

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Original analyses of a large vegetation cover dataset from Roosevelt National Forest in northern Colorado were carried out by Blackard (1998) and Blackard and Dean (1998; 2000). They compared the classification accuracies of linear and quadratic discriminant analysis (LDA and QDA) with artificial neural networks (ANN) and obtained an overall classification accuracy of 70.58% for a tuned ANN compared to 58.38% for LDA and 52.76% for QDA.

Because there has been tremendous development of machine learning classification methods over the last 35 years in both computer science and statistics, as well as substantial improvements in the speed of computer hardware, …

Optimizing Bioengineered Vascular Systems: A Genetic Algorithm Approach, Sima Mehri Kochaki

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Efficiency of current cell cultures producing biological products is limited due to accumulation of the product and waste on the cells. A previous work aims at assisting bioengineers in solving this problem by introducing a new set of cells which possess the ability to connect to one another and thus form a network. Once created, the network of cells can help the initial cellules by removing their waste and product as well as nourishing them. Our project explores a technique to be able to create the best network of such cells; hence maximizing the amount of metabolic product in the …

The Anatomy Of Virtual Manipulative Apps: Using Grounded Theory To Conceptualize And Evaluate Educational Apps That Contain Virtual Manipulatives, Jennifer M. Boyer-Thurgood

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This exploratory qualitative study used grounded theory to investigate the anatomy of educational apps that contain virtual manipulatives. For this study 100 virtual manipulatives within educational apps designed for the iPad were observed by the researcher in order to expand the explanations of and build theory about virtual manipulatives within apps. Affordance theory was used to frame all six phases of the study in which the researcher identified virtual manipulatives situated within educational apps, conducted observer-as-participant structured and unstructured observations, analyzed component data including field notes and memos using open and axial coding, created a conceptual framework, developed an evaluation …

Analysis Of Angles-Only Hybrid Space-Based/Ground-Based Approach For Geosynchronous Orbit Catalog Maintenance, Blythe A. Andrews

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Geosynchronous Equatorial Orbit (GEO) is critical to Earth communications, weather monitoring, and national defense. Orbit estimation of GEO objects is difficult due to physical constraints placed on ground-based tracking devices such as weather, object range, and tracking frequency restrictions. These constraints are commonly mitigated through the use of two-way signaling devices for cooperative GEO satellites. However, determining the position and velocity of uncooperative GEO satellites and/or objects is more challenging. The objective of this dissertation is to quantify the increased orbital accuracy of objects in the GEO catalog when the Air Force Space Command Space Surveillance Network (AFSPC SSN) is …

Effects Of Intentional Electromagnetic Interference On Analog To Digital Converter Measurements Of Sensor Outputs And General Purpose Input Output Pins, David A. Ware

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As technology becomes more prevalent, its application to safety and security in critical systems continues to increase. This leads to an increased dependence on sensors to provide an accurate view of the environment surrounding an application. These sensors can also be exploited by a malicious individual to attack a system and compromise its safety or security. These attacks change the reported value of a sensor so that it doesn't reflect the real situation. The systems in a car can be used as an example of this. Cars can have numerous sensors that measure a variety of things, including the car's …

Quantifying Riverbed Sediment Using Recreational-Grade Side Scan Sonar, Daniel Hamill

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Colorado River in Glen, Marble, and Grand Canyons is subject to a complex regulatory framework, including the Colorado River Compact, the Endangered Species Act, and the Grand Canyon Protection Act of 1992. Physical, biological, and cultural resources are extensively monitored by the Glen Canyon Dam Adaptive Management Program (GCDAMP) to assess the effect of Glen Canyon Dam (GCD) operations on the downstream environment. The GCDAMP consists of a diverse group of stakeholders who identify priority resources and agree upon water releases at GCD. Large expenditures of money have been devoted to monitoring physical and biological resources in Grand Canyon. …

Development And Application Of Hydraulic And Hydrogeologic Models To Better Inform Management Decisions, Trinity L. Stout

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Water is one of the most important and limited resources in regions with little rainfall. As populations continue to grow, so does the need for water. Individuals in water management positions need to be well informed in order to avoid potential negative effects concerning the overall quality and amount of water available for both people and the environment. In order to provide better information for these individuals, computer models and mathematical relationships are commonly developed to estimate the outcome of different situations regarding surface water and groundwater. Along these lines, this study focused on two modeling studies that provide information …

Estimating Accuracy Of Personal Identifiable Information In Integrated Data Systems, Amani "Mohammad Jum'h" Amin Shatnawi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Both government agencies and private companies rely on the collection of personal data on an ever-increasing scale. Out of necessity, person data include Personal Identifiable Information (PII), which is information that could potentially identify a specific individual. Many of these data would be integrated, so data analyst, policy makers or corporate officers can use it to make decisions or get a conclusion. Integrating data in a heterogeneous database environment create a need to estimate the accuracy of that data; without a valid assessment of accuracy there is a risk of coming with incorrect conclusions or making bad decision based on …

Database Auto Awesome: Enhancing Database-Centric Web Applications Through Informed Code Generation, Jonathan Adams

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Database Auto Awesome is an approach to enhancing web applications comprised of forms used to interact with stored information. It was inspired by Google's Auto Awesome tool, which provides automatic enhancements for photos. Database Auto Awesome aims to automatically or semi-automatically provide improvements to an application by expanding the functionality of the application and improving the existing code.

This thesis describes a tool that gathers information from the application and provides details on how the parts of the application work together. This information provides the details necessary to generate new portions of an application.

These enhancements are directed by the …

Geometric Facility Location Problems On Uncertain Data, Jingru Zhang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In this dissertation, we study several facility location problems on uncertain data. We mainly consider the k-center problem and many of its variations. These are classical problems in computer science and operations research. These problems on deterministic data have been studied extensively in the literature. We consider them on uncertain data because data in the real world is often associated with uncertainty due to measurement inaccuracy, sampling discrepancy, outdated data sources, resource limitation, etc. Although we focus on the theoretical study, the algorithms developed in this dissertation may find applications in other areas such as data clustering, wireless sensor …

Evaluating Utah 4-H Stem Curricula Used To Promote Stem In Utah 4-H Programs, Michelle D. Simmons

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Utah 4-H strives to ensure that youth receive the best that positive youth developmental programming has to offer in an endeavor to provide 4-H youth with the knowledge and skills that will given them an advantage in the workforce. The purpose of this study was to determine if Utah's Discover 4-H STEM curricula that is being used to promote STEM in Utah 4-H program met the outcomes of the National 4-H STEM logic model.

Writing Attitudes And Practices Of Content Area Teachers After Participating In The Central Utah Writing Project Summer Institute, Joseph P. Anson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study of four case studies looks at how secondary math, music, science, and social studies teachers' attitudes and classroom practices were affected by their participation in the Central Utah Writing Project (CUWP) summer institute. Participant interviews, observations, and artifacts were analyzed by looking at themes for effective professional development: a participant's personal interpretation of the experience (phenomenon), construction of one's own learning, active learning/participation in the professional development, the inclusion of authentic tasks, collaborative support community, inclusion of prior knowledge and/or experience, self-efficacy regarding one's own writing and the teaching of writing, motivation as a teacher, motivation as a …