Digital Commons Network^™

A Series Of Papers On Detecting Examinees Who Used A Flawed Answer Key, Marcus W. Scott

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

One way that examinees can gain an unfair advantage on a test is by having prior access to the test questions and their answers, known as preknowledge. Determining which examinees had preknowledge can be a difficult task. Sometimes, the compromised test content that examinees use to get preknowledge has mistakes in the answer key. Examinees who had preknowledge can be identified by determining whether they used this flawed answer key. This research consisted of three papers aimed at helping testing programs detect examinees who used a flawed answer key.

The first paper developed three methods for detecting examinees who used …

Breeding Season Ecology And Demography Of Lesser Scaup (Aythya Affinis) At Red Rock Lakes National Wildlife Refuge, Jeffrey M. Warren

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

It is hypothesized that individuals make reproductive decisions based on current assessments of their physiological condition and environmental conditions. For female lesser scaup (Aythya affinis), breeding occurs after an energetically costly spring migration. Increasing fat reserves (i.e., ‘body condition’) prior to breeding allows a female to produce a larger clutch of eggs, but time spent gaining body condition is costly in terms of time allowed to raise ducklings before freezing conditions in the fall. In Chapter 2 I explored rate of pre-breeding body condition gain in female lesser scaup, and how that rate influenced clutch size. Spring phenology, …

In-Situ Educational Research From Concept To Classroom Implementation: A Multiple Paper Dissertation, David Mark Weiss

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

An educational researcher sought to collaborate with a classroom instructor to introduce problem-based learning as a new teaching intervention. First, a classroom instructor was approached to consider how a problem-based learning instructional approach might fit with their existing curriculum plan. The researcher and the classroom teacher used a discussion framework to decide together how to best design a professional learning course meant to prepare the teacher to use the new techniques in their classroom. The teacher took the professional learning course and subsequently designed his own problem-based learning course. That course was then delivered to undergraduate students in a college …

Investigating The Climatology Of Mesospheric And Thermospheric Gravity Waves At High Northern Latitudes, Michael Negale

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

An important property of the Earth's atmosphere is its ability to support wave motions, and indeed, waves exist throughout the Earth's atmosphere at all times and all locations. What is the importance of these waves? Imagine standing on the beach as water waves come crashing into you. In this case, the waves transport energy and momentum to you, knocking you off balance. Similarly, waves in the atmosphere crash, known as breaking, but what do they crash into? They crash into the atmosphere knocking the atmosphere off balance in terms of the winds and temperatures. Although the Earth's atmosphere is full …

Marginal Mediation Analysis: A New Framework For Interpretable Mediated Effects, Tyson S. Barrett

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Mediation analysis is built to answer not only if one variable affects another, but how the effect takes place. However, it lacks interpretable effect size estimates in situations where the mediator (an intermediate variable) and/or the outcome is categorical or otherwise non-normally distributed. By integrating a powerful approach known as average marginal effects within mediation analysis—termed Marginal Mediation Analysis (MMA)—the issues regarding categorical mediators and/or outcomes are, in large part, resolved. This new approach allows the estimation of the indirect effects (those effects of the predictor that affect the outcome through the mediator) that are interpreted in the same way …

Elucidating Molecular Interactions Of Shigella Type Three Secretion System Components Critical For Pathogenesis, R. Alan Burgess

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Shigella are pathogenic bacteria which commonly infect human hosts through the fecal-oral route. As the causative agent of shigellosis, a disease characterized by severe diarrhea, nausea, and vomiting, Shigella are responsible for an estimated 90 million infections and 100,000 deaths each year. With the emergence of antibiotic resistant strains of Shigella, the need for alternative treatments methods has become critical to fighting outbreaks of shigellosis and drug resistant strains. One such method is to target the infection system of the bacteria, called the type three secretion system (T3SS). The T3SS includes a complex needle and syringe-like apparatus that is …

Integrated Systems Modeling To Improve Watershed Habitat Management And Decision Making, Ayman H. Alafifi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Existing river management tools prioritize human uses and provide for ecosystem water needs as minimum instream flow requirements. Management efforts to provide water for multiple human and ecological needs can be improved by tools that recommend when, where, and how to allocate water between competing users across a river basin. This dissertation presents a set of tools in three studies to help managers make decisions on the allocation of water and money to improve habitat quality and area. The first study develops a new metric to measure habitat quality and area for priority river, riparian, and wetland species. The second …

A Propeller Model Based On A Modern Numerical Lifting-Line Algorithm With An Iterative Semi-Free Wake Solver, Zachary S. Montgomery

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A fundamental aerodynamic analysis technique for a single straight fixed wing has been expounded upon and turned into a modern technique that can analyze multiple wings of more realistic shapes common on aircraft. This modern technique is extended further to apply towards propellers. A method to overcome propeller analysis problems at low airspeeds is presented. This method is compared to more traditional propeller analysis techniques.

Phenology Of A Southern Population Of Mountain Pine Beetle (Dendroctonus Ponderosae), Anne Elise Mcmanis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Mountain pine beetle (Dendroctonus ponderosae, Hopkins) is a major disturbance agent in pine ecosystems of western North America. Adaptation to local climates has resulted in primarily univoltine (one generation per year) generation timing across a thermally diverse latitudinal gradient. We hypothesized that this pattern in total development time is shaped by selection for slower developmental rates, altered developmental thresholds, or oviposition rates in southern populations inhabiting warmer climates. To investigate traits responsible for latitudinal differences we measured lifestage-specific development of southern mountain pine beetle eggs, larvae and pupae across a range of temperatures. We also describe and model …

Learning Logic: A Mixed Methods Study To Examine The Effects Of Context Ordering On Reasoning About Conditionals, Christina W. Lommatsch

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Logical statements are prevalent in mathematics, the sciences, law, and many areas of everyday life. The most common logical statements are conditionals, which have the form “If H..., then C...,” where “H” is a hypothesis (or condition) to be satisfied and “C” is a conclusion to follow. Reasoning about conditionals is a skill that is only superficially understood by most individuals and depends on four main conditional contexts (e.g., intuitive, abstract, symbolic, or counterintuitive). The purpose of this study was to test a theory about the effects of context ordering on reasoning about conditionals. To test the theory, the researcher …

Facilitators Of Diné (Navajo) Student Access, Enrollment, And Persistence In Postsecondary Education: An Ecological Systems Perspective, Christina Hartman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Diné (Navajo) students drop out of high school and postsecondary education at higher than average rates. The purpose of this study was to investigate how Diné students currently enrolled in college describe the factors that supported their pursuit of higher education. Bronfenbrenner’s ecological systems theory was used as a framework and to identify and analyze factors that influence access, enrollment, and participation in higher education. The Diné participants in this study were six students enrolled in postsecondary education at the time of this research, recruited from two university campuses in the Southwestern U.S. Each student participated in a semistructured interview …

Assessing The Effects Of Local Turbulence And Velocity Profiles On Electromagnetic Flow Meter Accuracy, Kade J. Beck

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this research was to assess the effects of local turbulence and velocity profiles on electromagnetic (magnetic) flow meters. According to the American Water Works Association, “No tool available to water utilities has played a greater part in the conservation of water than the water meter (AWWA 2002).” Consequently, it is imperative to understand what variables may influence magnetic flow meter accuracy.

Even though other researchers have explored the effects of turbulence profile development on orifice plates, the literature is not clear how magnetic flow meters respond to the effect of local turbulence. Accordingly, this study investigated the …

Three Essays In Economics Of Prey-Predator Relation, Dong-Hun Go

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This dissertation explores how natural ecosystem can be integrated with economic system through two case studies of multiple species interactions, or predator-prey relations. By the inclusion of biological, ecological and economic aspects, the integrated approaches aim at more clearly understanding of how regional ecosystem and economy interact with each other, given threats of resource extinction and environmental shock. I also explain strategies and policy regimes that can be considered to achieve efficient and sustainable ecosystem management in those circumstances.

The first case study focuses on a predator-prey relation in the Pacific Ocean between the United States and Canada, where endangered/threatened …

Universal Mobile Service Execution Framework For Device-To-Device Collaborations, Minh Le

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

There are high demands of effective and high-performance of collaborations between mobile devices in the places where traditional Internet connections are unavailable, unreliable, or significantly overburdened, such as on a battlefield, disaster zones, isolated rural areas, or crowded public venues. To enable collaboration among the devices in opportunistic networks, code offloading and Remote Method Invocation are the two major mechanisms to ensure code portions of applications are successfully transmitted to and executed on the remote platforms. Although these domains are highly enjoyed in research for a decade, the limitations of multi-device connectivity, system error handling or cross platform compatibility prohibit …

Geometric Algorithms For Intervals And Related Problems, Shimin Li

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In this dissertation, we study several problems related to intervals and develop efficient algorithms for them. Interval problems have many applications in reality because many objects, values, and ranges are intervals in nature, such as time intervals, distances, line segments, probabilities, etc. Problems on intervals are gaining attention also because intervals are among the most basic geometric objects, and for the same reason, computational geometry techniques find useful for attacking these problems. Specifically, the problems we study in this dissertation includes the following: balanced splitting on weighted intervals, minimizing the movements of spreading points, dispersing points on intervals, multiple barrier …

Relationships Among Preschool Attendance, Type, And Quality And Early Mathematical Literacy, Jennifer E. Throndsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As students enter kindergarten, some students are more academically prepared than others. This study looked at the relationships among preschool attendance, preschool type (i.e., public, private, Head Start, and home-based technology providers) and preschool quality and early mathematical literacy skills for diverse students. The study sought to answer three research questions: What is the relationship between preschool attendance and early mathematical literacy? What is the relationship between preschool type and early mathematical literacy? What is the relationship between preschool quality and early mathematical literacy? Within each research question, there was also an investigation to see if there were differing effects …

The Use Of Microfluidics And Dielectrophoresis For Separation, Concentration, And Identification Of Bacteria, Cynthia Hanson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Typical bacterial analysis involves culturing and visualizing colonies on an array of agar plates. The growth patterns and colors among the array are used to identify the bacteria. For fast growing bacteria such as Escherichia coli, analysis will take one to two days. However, slow growing bacteria such as mycobacteria can take weeks to identify. In addition, there are some species of bacteria that are viable but nonculturable. This lengthy analysis time is unacceptable for life-threatening infections and emergency situations. It is clear that to decrease the analysis of the bacteria, the culturing and growth steps must be avoided. …

A Model For Bioaugmented Anaerobic Granule, Amitesh Mahajan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In this study, we have created a simulation model which is concerned about digesting cellulose, as a major component of microalgae in a bioreactor. This model is designed to generate a computational model that simulates the process of granulation in anaerobic sludge and aims to investigate scenarios of possible granular bioaugmentation. Once a mature granule is formed, protein is used as an alternative substrate that will be supplied to a mature granule. Protein, being a main component of cyanobacteria, will promote growth and incorporation of a cell type that can degrade protein (selective pressure). The model developed in a cDynoMiCs …

Multi-Stop Routing Optimization: A Genetic Algorithm Approach, Abbas Hommadi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In this research, we investigate and propose new operators to improve Genetic Algorithm’s performance to solve the multi-stop routing problem. In a multi-stop route, a user starts at point x, visits all destinations exactly once, and then return to the same starting point. In this thesis, we are interested in two types of this problem. The first type is when the distance among destinations is fixed. In this case, it is called static traveling salesman problem. The second type is when the cost among destinations is affected by traffic congestion. Thus, the time among destinations changes during the day. In …

The Role Of Recoverable And Non-Recoverable Defects In Dc Electrical Aging Of Highly Disordered Insulating Materials, Allen Andersen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Electrical insulation under high voltage can eventually fail, causing critical damage to electronics. Such electrostatic discharge (ESD) is the primary source of anomalies or failures on spacecraft due to charged particles from the Sun or planetary radiation belts accumulating in spacecraft insulators. High-voltage direct current power distribution is another example of a growing industry that needs to estimate the operational lifetime of electrical insulation. My research compares laboratory tests of ESD events in common insulating materials to a physics-based model of breakdown. This model of breakdown is based on the approximation that there are two primary types of defects in …

In Situ Detection Of Road Lanes Using Raspberry Pi, Ashwani Chahal

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A self-driven car is a vehicle that can drive without human intervention by making correct decisions based on the environmental conditions. Since the innovation is in its beginning periods, totally moving beyond the human inclusion is still a long shot. However, rapid technological advancements are being made towards the safety of the driver and the passengers. One such safety feature is a Lane Detection System that empowers vehicle to detect road lane lines in various climate conditions.

This research provides a feasible and economical solution to detect the road lane lines while driving in a sunny, rainy, or snowy weather …

Modeling The Spread Of Alfalfa Stem Nematodes: Insights Into Their Dynamics And Control, Scott G. Jordan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Alfalfa is a major cash crop in the western United States, where fields that are infested with the alfalfa stem nematode (Ditylenchus dipsaci) can be found. With no nematicides available to control alfalfa stem nematode spread, growers can use nematode resistant varieties of alfalfa to manage nematode populations in a field. A deterministic, discrete-time, host-parasite model is presented that describes the spread of alfalfa stem nematodes on resistant hosts that was fit to experimental data obtained in Weber County, Utah. Numerical results obtained from simulations with the model are used to compare how varying levels of resistance can affect …

Be Cool, Stay In School: The Habits, Resources, And Confidence College Students Need To Succeed, Matthew Staheli

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Earning a college degree yields many benefits. In addition to an increased income, college degree earners generally have greater job satisfaction, make healthier life choices, are better communicators, and have greater social mobility. Even with all of these benefits, however, some colleges are seeing graduation rates as low as 32%. One of the greatest contributing factors affecting the dropout rate of undergraduate college students is poor academic performance in their courses. In this study, we sought to identify several academic resources, study behaviors, academic self-confidence scores, and demographic information to assess what types of behaviors and resources may lead to …

Importance Of Exposure Time On Digital Image Correlation (Dic) At Extreme Temperatures, Thinh Quang Thai

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Extreme temperatures have increasingly played an important role in engineering applications, including leading edges during hypersonic flight, spacecraft re-entry, and propulsion systems. In order to design for such thermo-mechanical conditions, materials must be characterized using suitable measurement methods. DIC is a popular and versatile method in full-field measurement. In brief, DIC compares images of a sample between its undeformed and deformed state in order to get displacement and strain field maps. Since the images are acquired from digital cameras, it is important to have high contrast images for meaningful correlation. Exposure time is a pivotal camera setting relating to camera …

Quaternary Incision, Salt Tectonism, And Landscape Evolution Of Moab-Spanish Valley, Utah, James P. Mauch

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

To study the history of processes that shape the Earth’s surface, geologists look for markers in the landscape that they can date and use to measure change. Rivers leave such markers in their deposits and terrace landforms and in the overall shape of their elevation profile from head to toe. This thesis uses luminescence and cosmogenic methods to date the sediment in terraces to determine when the river deposited it. Field mapping and global positioning system (GPS) surveying are also used to measure the distance between terrace levels to quantify how much change has occurred. This study seeks to answer …

Longitudinal Thermal And Solute Dynamics In Regulated Rivers, Muhammad Rezaul Haider

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Dam releases increase river stage and can reverse groundwater movement into and out of the river. As the flood, thermal, and solute waves travel downstream in a regulated river, the size of the waves is anticipated to be affected both by river processes and exchanges with near river groundwater. This study established a modeling framework to quantify the influences of the groundwater exchanges on the temperatures and solute concentration dynamics along regulated rivers. The wave properties, volume of exchanges, conservative solute mass exchanges, and heat energy exchanges were calculated as a function of time and distance downstream. Results show that …

Water Surface Impact And Ricochet Of Deformable Elastomeric Spheres, Randy Craig Hurd

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Soft and deformable silicone rubber spheres ricochet from a water surface when rigid spheres and disks (or skipping stones) cannot. This dissertation investigates why these objects are able to skip so successfully. High speed cameras allow us to see that these unique spheres deform significantly as they impact the water surface, flattening into pancake-like shapes with greater area. Though the water entry behavior of deformable spheres deviates from that of rigid spheres, our research shows that if this deformation is accounted for, their behavior can be predicted from previously established methods. Soft spheres skip more easily because they deform significantly …

Optimizing Barrier Removal To Restore Connectivity In Utah’S Weber Basin, Maggi Kraft

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

River barriers, such as dams, culverts and diversions are important for water conveyance, but disrupt river ecosystems and hydrologic processes. River barrier removal is increasingly used to restore and improve river habitat and connectivity. Most past barrier removal projects prioritized individual barriers using score-and-rank techniques, neglecting the spatial structure and cumulative change from multiple barrier removals. Similarly, most water demand models satisfy human water uses or, only prioritize aquatic habitat, failing to include both human and environmental water use benefits. In this study, a dual objective optimization model identified in-stream barriers that impede quality-weighted aquatic habitat connectivity for Bonneville cutthroat …

Advancing The Cyberinfrastructure For Integrated Water Resources Modeling, Caleb A. Buahin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Like other scientists, hydrologists encode mathematical formulations that simulate various hydrologic processes as computer programs so that problems with water resource management that would otherwise be manually intractable can be solved efficiently. These computer models are typically developed to answer specific questions within a specific study domain. For example, one computer model may be developed to solve for magnitudes of water flow and water levels in an aquifer while another may be developed to solve for magnitudes of water flow through a water distribution network of pipes and reservoirs. Interactions between different processes are often ignored or are approximated using …

Usarray Imaging Of North American Continental Crust, Xiaofei Ma

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The layered structure and bulk composition of continental crust contains important clues about its history of mountain-building, about its magmatic evolution, and about dynamical processes that continue to happen now. Geophysical and geological features such as gravity anomalies, surface topography, lithospheric strength and the deformation that drives the earthquake cycle are all directly related to deep crustal chemistry and the movement of materials through the crust that alter that chemistry.

The North American continental crust records billions of years of history of tectonic and dynamical changes. The western U.S. is currently experiencing a diverse array of dynamical processes including modification …