Digital Commons Network^™

Calculating Willingness-To-Pay As A Function Of Biophysical Water Quality And Water Quality Perceptions, Carlos G. Silva

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

When estimating economic value associated with changes in water quality, recreation demand models typically depend upon either (i) biophysical measures of water quality as collected by natural scientists or (ii) the perception of water quality by recreationists. Models based upon biophysical metrics (such as oxygen concentration, pollutant concentrations, Secchi depth measurements, etc.) operate on the assumption that people can perceive and respond to these metrics, or respond to factors that are, indeed, correlated with the biophysical measure. Economists have often estimated willingness-to-pay (WTP) measures associated with unit changes in biophysical measures without examining the degree to which the measures are …

Understanding Local Perceptions And The Role Of Historical Context In Ecotourism Development: A Case Study Of St. Kitts, Amber Greening

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ecotourism is a popular tool for the conservation of fragile ecosystems and local development of the communities surrounding them. It is widely argued that the key to effective and sustainable ecotourism programs relies on the depth of community involvement and support. This research reveals a better understanding of community members’ perceptions of ecotourism and conservation, and how these perceptions potentially influence participation in current and future ecotourism projects within the villages of Cayon and Keys on the Caribbean island of St. Kitts. Data were collected through several qualitative methods including: face-to-face surveys with Cayon and Keys villagers; interviews with government …

The Human Dimensions Of Climate Change: Smallholder Perception And Adaptation In The Loess Plateau Region Of China, Morey Burnham

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Climate change poses problems for agriculture in the Global South. Smallholders in the Global South are often considered highly vulnerable to climate change as a result of their farms being located in marginal environments, their insecure land tenure and lack of technology, and their participation in unpredictable regional and world markets. Analyzing how smallholders perceive climate change and attendant risk, the factors that enable and constrain their adaptive capacity, and the social impacts of state led projects designed to mitigate the impacts of climate change may provide crucial insights for developing effective climate adaption projects and policies. This research examined …

Molecular Systematics, Historical Biogeography, And Evolution Of Spider Wasps (Hymenoptera: Pompilidae), Juanita Rodriguez

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The study of the diversity and classification of any group of organisms provides a foundation for further scientific studies in ecology, evolution, and conservation. Insects are among the most diverse organisms that inhabit the planet, but knowledge of their diversity and classification is still limited. One understudied group of insects is spider wasps. These are solitary parasitoids that use one spider to lay a single egg. There are approximately 5,000 described species, and many more to be described. Unfortunately, fewer than 10 scientists worldwide study these insects. One reason the group has not been very well studied is the difficulty …

A Computational Fluid Dynamics Validation Experiment For Forced And Mixed Convection On A Vertical Heated Plate, Jeff Robert Harris

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A computational fluid dynamics (CFD) validation experiment is conducted for flow over a heated vertical plate. The design of the experiment to meet CFD validation standards is described. Many experiments and simulations have been completed in past studies, but none measure or present the necessary boundary conditions to define the simulation. Experimental measurements of heated flow are presented, along with corresponding boundary conditions sufficient to define the simulation's boundary conditions. Some simulation results are described, but a complete validation study is not included. The simulations are conducted by the experimentalist to ensure all necessary boundary conditions are being measured. This …

Mesoscale Deformational Features Near Outcrop Analogs Of A Reservoir-Seal Interface: Implications For Seal Failure, Santiago L. Flores

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The boundary that separates reservoir rocks from caprock seals is generally considered a flow barrier for reservoir fluids. Buoyant fluids do no flow through the caprocks because they have low permeability and molecular forces at the base of the caprock resist upward flow. Deformation at the reservoir/caprock boundary may include fractures that increase permeability and lessen the effect of the molecular forces.

The injection and storage of carbon dioxide (CO₂) in porous sandstone with effective top seals below earth’s surface is a possible solution for reducing the amount of human-created CO₂ in the atmosphere. Uplift and erosion …

Pathway Pioneer: A Web-Based Graphical Tool For The Organization And Flux Analysis Of Metabolic Networks, Sumit Kumar Singh

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Every so often the field of genome-scale metabolic networks undergoes radical changes, each bringing its own complexity and challenges. The existing visualization tools, owing to their inability to assist in generating layouts suitable for easy readability and conceptualization, hinder further advancement. The lack of in-depth comprehensible representation of the intricacies of interaction and arrangements within the network topology prevents researchers from being able to advance at a faster speed despite the growing number of networks and systems. The far and wide diverse standards, layout schemas and network formats of the biological realm contribute to the existing challenges of developing visualization …

Pathway Pioneer: A Web-Based Metabolic Network Layout Extension, Harsh Dosi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The number and complexity of genome-scale metabolic networks have seen a rapid growth in the past 10 years. Today, more than 450 genome-scale metabolic reconstructions of biological systems are characterized and existing models are extended. With the growing influence of these reconstructions on biomedical and biological research, the field has observed a shift from an inward focus on method development to an outward focus on application development.

Static state analysis of metabolic networks in textual format is too cumbersome and time consuming. In addition, visualization and arrangement of these networks to facilitate their analysis is an open research problem. A …

Family-Wise Error Rate Control In Quantitative Trait Loci (Qtl) Mapping And Gene Ontology Graphs With Remarks On Family Selection, Garrett Saunders

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

One of the great aims of statistics, the science of collecting, analyzing, and interpreting data, is to protect against the probability of falsely rejecting an accepted claim, or hypothesis, given observed data stemming from some experiment. This is generally known as protecting against a Type I Error, or controlling the Type I Error rate. The extension of this protection against Type I Errors to the situation where thousands upon thousands of hypotheses are examined simultaneously is known as multiple hypothesis testing. This dissertation presents an improvement to an existing multiple hypothesis testing approach, the Focus Level method, specific to gene …

Effective Graph-Based Content--Based Image Retrieval Systems For Large-Scale And Small-Scale Image Databases, Ran Chang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Digital imaging was a great invention in the last century. Since digital cameras became popular in the public, a large amount of digital images emerged in the late of the twentieth century. How to manage the huge amount of images and find desired images among them became an urgent issue during the same period.

Techniques of retrieving a desired image are generally categorized into two basic classes. One relies on text-based key words to retrieve desired images in the image
database. The other one relies on image-based queries to retrieve desired images in the image database. The second technique is …

An Algorithm To Recognize Multi-Stable Behavior From An Ensemble Of Stochastic Simulation Runs, Eduardo Monzon

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Synthetic biological designers are demanding tools to help with the design and verification process of new biological models. Some of the most common tools available aggregate multiple simulation results into one “clean” trajectory that hopefully is representative of the system’s behavior. However, for systems exhibiting multiple stable states, these techniques fail to show all the possible trajectories of the system. This work introduces a method capable of detecting the presence of more than one “typical” trajectory in a system, which can also be integrated with other available simulation tools.

Constraints On Patterns Of Abundance And Aggregation In Biological Systems, Kenneth J. Locey

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Understanding the mechanisms that structure biological systems is a primary goal of biology. My research shows that the biological structure is constrained in important ways by general variables such as the number of base pairs in a genome and the number of individuals and species in a community. I used a combination of macroecology, bioinformatics, statistics, mathematics, and advanced computing to pursue my research and published several peer-reviewed scientific manuscripts and open-source software as a result.

I was funded through a combination of fellowships and scholarships awarded by the Utah State University School of Graduate Studies, College of Science, and …

Development Of A Coupled Fluid And Colloidall Particle Transport Model, Scott Ripplinger

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A colloidal system usually refers to when very small particles are suspended within a solution. The study of these systems encompasses a variety of cases including bacteria in ground water, blood cells and platelets in blood plasma, and river silt transport. Taking a look at these kinds of systems using computer simulation can provide a great deal of insight into how they work. Most approaches to date do not look at the details of the system, however, and are specific to given system. In this study a program called OpenFOAM is used as a basis to build a computer simulation …

Unified Model Of Charge Transport In Insulating Polymeric Materials, Alec Sim

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Charge transport, charging, and subsequent electrostatic discharge due to interactions with the space environment are primary concerns of spacecraft designers. Developing a physical understanding of the interactions of charge with the multitude of materials that spacecraft are composed of is a critical step in understanding and mitigating both short-term and long-term spacecraft degradation. In particular, the study of charge transport in highly insulating materials is critical as they store charge longer, with higher capacity, and with greater destructive capability than other materials.

The Utah State University Materials Physics Group, with the funding of the NASA James Webb Space Telescope project …

Alluvial Geochronology And Watershed Analysis Of The Golo River, Northeastern Corsica, France, Emilee M. Skyles

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Golo River in Corsica, France, is a short, steep river (~95 km, 2706 m relief) in the Western Mediterranean with formerly glaciated headwaters. The small size and location of the Golo River make this system ideal for observing the influence of climate and sea-level change on river dynamics over the 100,000 years. A rapidly advancing dating technique, optically stimulated luminescence, was utilized to determine the timing of these river deposits on the coastal plain in order to frame them in the context of previous glacial and interglacial episodes. Climate fluctuations in the headwaters supplied the vast majority of sediment …

Computer Self-Efficacy, Cognitive Actions, And Metacognitive Strategies Of High School Students While Engaged In Interactive Learning Modules, Harry Budi Santoso

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this research was to investigate high school students’ computer self-efficacy, cognitive actions, and metacognitive strategies in a self-regulated learning (SRL) framework while utilizing an interactive learning module. The researcher hypothesized that computer self-efficacy is correlated positively with cognitive actions and metacognitive strategies while the students are engaged with interactive learning modules. This research used a mixed-methods approach to answer the research questions. Two research questions guided this research: (1) How is students’ computer self-efficacy related to cognitive actions and metacognitive strategies while using interactive learning modules?; and (2) How do students plan monitor their cognitive actions, and …

Substrate Binding And Reduction Mechanism Of Molybdenum Nitrogenase, Zhiyong Yang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As a key constituent of proteins, nucleic acids, and other biomolecules, nitrogen is essential to all living organisms including human beings. Dinitrogen represents the largest pool of nitrogen, about 79% of the Earth’s atmosphere, yet it is unusable by most living organisms due to its inertness. There are two ways to fix this inert dinitrogen to usable ammonia. One is the industrial Haber-Bosch process, which needs to be conducted at high temperature and pressure. This process uses a lot of the non-renewable fossil fuel as the energy source. The other major pathway is the biological nitrogen fixation carried out by …

Mixing The Emic And Etic Perspectives: A Study Exploring Development Of Fixed-Answer Questions To Measure In-Service Teachers' Technological Pedagogical Content Knowledge, M. Brooke Robertshaw

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this dissertation study was to develop fixed-answer questions to measure teachers' technological pedagogical content knowledge when teaching with online learning resources. Technological pedagogical content knowledge (TPACK) is a framework to describe the kind of knowledge that teachers use when they are teaching with technology. Online learning resources include text, video, images, and interactive websites that teachers can use to help teach subject matter to their students. Fixed-answer questions are the kinds of questions found on standardized tests like the SAT, and tests that K-12 students take as a part of state and national testing. Many measures have …

Transparent Antennas For Solar Cell Integration, Tursunjan Yasin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Transparent patch antennas have a certain level of optical transparency. Highly transparent patch antennas can be integrated with the solar panels of small satellites, which are becoming increasingly important in space exploration. Traditional patch antennas, which are not transparent, are employed on small satellites and compete with solar cells for surface area. But a transparent patch antenna can be placed directly on top of the solar cells and alleviate the issue of limited surface real estate. For such an integration, a high optical transparency of the patch antenna is required from the solar cells’ point of view since the solar …

Mechanisms Of Vegetation-Induced Channel Narrowing On An Unregulated Canyon-Bound River, Rebecca Blanche Manners

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The accurate prediction of river channel width remains a fundamental area of investigation in the field of geomorphology. River managers and scientists are interested in understanding how a channel will respond to environmental perturbations such as altered runoff patterns from climate change, a new dam, or a pulse of sediment from a landslide. Increasingly, studies that focus on this question acknowledge the importance of accounting for the vegetation that lines the river banks. For this dissertation, I strove to identify some of the primary ways by which vegetation affects channel width.

At a fundamental level, vegetation influences the size of …

Examining Relationships Among Student Interim Proficiency, School Environment, And Student End-Of-Year Proficiency, Kathy Janzen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Research on variables that are related to student academic proficiency has intensified due to the increased emphasis on high achievement for all students. The purpose of this correlational study was to explore the relative strength of the relationship between the school's learning environment and student achievement, and a literacy benchmark assessment and student achievement. Schools in the state of Utah that administered the Indicators of School Quality (ISQ) survey during the 2010-2011 school year and the Dynamic Indicators of Early Literacy Skills (DIBELS) assessments during the same school year were included in the study.

The study examined a combination of …

Experimental Analysis Of The Effects Of Manipulations In Weighted Voting Games, Ramoni Olaoluwa Lasisi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This dissertation investigates weighted voting games and three methods of manipulating those games, called splitting, merging, and annexation. The manipulations involve an agent or some agents misrepresenting their identities in anticipation of gaining more power over the outcomes of games. Indeed, in open anonymous environments, manipulation can be easy and cheap to achieve. We provide clear and sufficient discussion on related work and backgrounds to motivate this research topic, which certainly deserves attention. Weighted voting games are among key cooperative games, and the manipulations considered in this dissertation are natural, and have practical applications, that are likely …

Integrating Technology, Curriculum, And Online Resources: A Multilevel Model Study Of Impacts On Science Teachers And Students, Lei Ye

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This scale-up study investigated the impact of a teacher technology tool (Curriculum Customization Service, CCS), curriculum, and online resources on earth science teachers’ attitudes, beliefs, and practices and on students’ achievement and engagement with science learning. Participants included 73 teachers and over 2,000 ninth grade students within five public school districts in the western U.S.

To assess the impact on teachers, changes between pre- and postsurveys were examined. Results suggest that the CCS tool appeared to significantly increase both
teachers’ awareness of other earth science teachers’ practices and teachers’ frequency of using interactive resources in their lesson planning and classroom …

Two Scenes From Utah's Stratigraphic Record: Neoproterozoic Snowball Earth, Before And After, Dawn Schmidli Hayes

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research is focused on rock units deposited in northern Utah before and after global glacial events of unprecedented magnitude, commonly referred to as
“Snowball Earth” glaciations. The rock units deposited prior to the beginning of these glaciations (~770 to 740 million years ago) include the Uinta Mountain Group in Utah’s Uinta Mountains. Rock units deposited after the glaciations (either ~665 or ~635 million years ago) include parts of the Kelley Canyon Formation on Antelope Island in the Great Salt Lake. These rocks, deposited in shallow ocean environments, record the history of life and ocean chemistry just before and after …

Functional Ontologies And Their Application To Hydrologic Modeling: Development Of An Integrated Semantic And Procedural Knowledge Model And Reasoning Engine, Aaron Range Byrd

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In hydrology we straddle the domains of science and engineering. As hydrologists our goal is to predict the movement and volume of water. As scientists we seek to improve our understanding of water-related processes and how to model them. As engineers we seek to be able answer specific water-related questions to provide protection and an essential resource for the people we serve. Underlying all of our work is a body of knowledge that we have developed and continue to develop. This knowledge involves many aspects, such as the role of various hydrologic processes, how to obtain data, computational models that …

Formation, Deformation, And Incision Of Colorado River Terraces Upstream Of Moab, Utah, Andrew P. Jochems

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The history of rivers is laid down as sediment in all landscapes, typically as a function of climate, geologic structures, and/or changes in sea level. When a river abandons its floodplain, this sediment collectively constitutes a landform called a fluvial terrace. Terraces are used to unlock prior characteristics of a river flowing through a given area at both local and regional scales. Dating terrace sediment allows comparison to known changes in climate and geologic deformation, two significant controls on the hydraulics of rivers and the deposition of their sediment loads.

The importance of terraces lies in their utility as markers …

Modeling Habitat Use Of A Fringe Greater Sage-Grouse Population At Multiple Spatial Scales, Anya Cheyenne Burnett

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Greater sage-grouse (Centrocercus urophasianus; hereafter sage-grouse) are a prominent bird species of sagebrush-dominated landscapes across the western United States. Over the past 15 years, sage-grouse have gained international attention due to decreasing population trends despite management efforts. In 2010 the U.S. Fish and Wildlife Service designated this species as warranted for listing under the Endangered Species Act, but the listing was precluded by other species at higher conservation risk. Habitat loss, degradation, and fragmentation have been implicated as primary sources of declines in sage-grouse distribution and abundance. The Bald Hills population in southwestern Utah occupies an area with …

Relationship Between Occupational Complexity And Dementia Risk In Late-Life: A Population Study, Daylee Rose Greene

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

According to cognitive reserve theory, challenging and/or stimulating cognitive activities can build a theoretical reserve, which may lead to a delay in the clinical expression of dementia and/or Alzheimer's disease. These cognitively stimulating activities are thought to build cognitive strategies and neural pathways that are more efficient, enabling the individual to live symptom-free for a longer period of time. One mechanism through which cognitive reserve can be built is by participating in an occupation high in cognitive complexity. When individuals hold an occupation that is high in complexity, they may build their cognitive reserve in such a manner as to …

Understanding Successful Japanese Language Programs: Utah Case Study, Timothy G. Stout

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Recent world events have caused Americans to reassess national political, economic, and educational priorities, resulting in a shift towards Asia. The schools in response have begun to introduce less commonly taught languages, such as Japanese and Chinese. Many Utah public schools have tried to implement less commonly taught language programs. Some have succeeded, and other others have not. The purpose of this study was to understand how and why some schools were able to successfully integrate less commonly taught language programs, and why others were not.

The results of this study suggest that the factors relating to students’ interests and …

Verification And Validation Of The Spalart-Allmaras Turbulence Model For Strand Grids, Oisin Tong

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The strand-Cartesian grid approach is a unique method of generating and computing fluid dynamic simulations. The strand-Cartesian approach provides highly desirable qualities of fully-automatic grid generation and high-order accuracy. This thesis focuses on the implementation of the Spalart-Allmaras turbulence model to the strand-Cartesian grid framework. Verification and validation is required to ensure correct implementation of the turbulence model.

Mathematical code verification is used to ensure correct implementation of new algorithms within the code framework. The Spalart-Allmaras model is verified with the Method of Manufactured Solutions (MMS). MMS shows second-order convergence, which implies that the new algorithms are correctly implemented.

Validation …