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Ensemble Methods For Dynamic Data Assimilation Of Chemical Observations In Atmospheric Models, Adrian Sandu, Emil Constantinescu, Gregory R. Carmichael, Tianfeng Chai, Dacian Daescu, John H. Seinfeld

Mathematics and Statistics Faculty Publications and Presentations

The task of providing an optimal analysis of the state of the atmosphere requires the development of dynamic data-driven systems (DDDAS) that efficiently integrate the observational data and the models. Data assimilation, the dynamic incorporation of additional data into an executing application, is an essential DDDAS concept with wide applicability. In this paper we discuss practical aspects of nonlinear ensemble Kalman data assimilation applied to atmospheric chemical transport models. We highlight the challenges encountered in this approach such as filter divergence and spurious corrections, and propose solutions to overcome them, such as background covariance inflation and filter localization. The predictability …

Does Non-Steroidal Anti-Inflammatory Drug (Nsaid) Use Affect Dementia Progression And Survival Rates In Alzheimer's Disease? The Cache County Study, Trevor R. Buckley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Alzheimer's disease (AD) has multiple factors that contribute to the disease process. Among these is a state of chronic inflammation that is endured by the brain during the aging process. The use of non-steroidal anti-inflammatory drugs (NSAIDs) decreases the amount of neuroinflammation sustained by the brain, and greater levels of NSAID use have been demonstrated to be associated with decreased probability of developing AD. This study looked at whether greater rates of NSAID use were also associated with decreased rates of cognitive and funtional decline and survival in a population-based sample of persons with AD. Linear mixed models failed to …

Environmental Sensor Anomaly Detection Using Learning Machines, Erick F. Conde

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The search for improvements in the quality assurance/quality control (QA/QC) of real-time environmental measurements has been a field well exploited in recent years. These measurements describe actual environmental conditions and processes that provide relevant information upon which water quality management decisions are based. In situ sensors (located at the site of interest) are commonly used for such real-time measurement purposes. However, the performance of these types of sensors can be affected by such things as human factors, lack of necessary maintenance, flaws on the transmission line or any part of the sensor, and unexpected changes in the sensors surrounding conditions. …

Distributed Electrical Power System In Cubesat Applications, Robert Burt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The cubesat spacecraft was conceived over ten years ago. Since that time, close to 100 cubesat satellites have either been launched or are in the process of construction. Although started as an educational teaching tool, the cubesat is gaining popularity in the satellite industry and is making inroads as a standard architecture for many nano and pico satellite applications. The electrical power system for the cubesat class satellites almost exclusively conforms to a centralized architecture.

This thesis researches the potential of using a distributed architecture for the cubesat power system. There are several key advantages of a distributed architecture that …

Outcomes Of Rotator Cuff Surgery In Utah Workers’ Compensation Patients, Jennifer R. Grewe

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The rotator cuff is responsible for the lifting function of the shoulder and the circular movement of the arm. Rotator cuff injuries are the most common problem for the shoulder and account for approximately 4.1 million annual physicians visits. Approximately 20.7% of the population has at least one rotator cuff tear and more than 75,000 individuals will have rotator cuff surgery each year. Medical and compensation costs associated with a rotator cuff surgery are increasing and current estimated annual costs exceed 2 billion dollars. The increasing prevalence and cost associated with rotator cuff injuries in the United States population represents …

Effects Of Tannin-Containing Feed On Haemonchous Contortus In Sheep And Its Behavioral Implications, Jessica A. Juhnke

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Herbivores prefer foods that supply required nutrients and avoid those with excess nutrients and plant secondary compounds (PSC). Nevertheless, PSC such as condensed tannins can provide beneficial medicinal effects to herbivores. The objectives of this study were to determine: 1) if parasitized lambs increased preference for a tannin-rich food after they experienced the beneficial antiparasitic effects of tannins relative to parasitized lambs that did not experience such benefits, 2) if preference for the tannin-containing food in the former group decreased when parasite burdens subsided, and 3) if the tannin-enriched food decreased parasitic burdens.

Twenty-two lambs were familiarized with beet pulp …

Molecular Interactions Of Salmonella With The Host Epithelium In Presence Of Commensals, Prerak T. Desai

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Food-borne infections are a major source of mortality and morbidity. Salmonella causes the highest number of Food-borne bacterial infections in the US. This work contributes towards developing strategies to control Salmonella by (a) defining receptors used by Salmonella to adhere to and invade the host epithelium; (b) developing a host receptor based rapid detection method for the pathogen in food matrix; (C) and defining mechanisms of how probiotics can help alleviate Salmonella-induced cell death in the host epithelium.

We developed a cell-cell crosslinking method to discover host-microbe receptors, and discovered three new receptor-ligand interactions. Interaction of Salmonella Ef-Tu with …

A Pilot Study Of Solution-Focused Brief Therapeutic Intervention For Couples, J. Wade Stewart

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A program was set to provide two 2-hour relationship consultations for couples. The purpose of this program was to attract couples that would not normally seek traditional therapy and/or relationship enrichment programs. The consultations were scheduled a month apart and were designed to be collaborative; the couple offered ideas for behaviors that they wanted to work on. Before the first consultation, each individual filled out several questionnaires about their relationship. In the initial session, the consultant reviewed the results with the couple pointing out the strengths of the couple. In addition, during the initial session, the couple also collaboratively created …

Asymptotic Multiphysics Modeling Of Composite Beams, Qi Wang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A series of composite beam models are constructed for efficient high-fidelity beam analysis based on the variational-asymptotic method (VAM). Without invoking any a priori kinematic assumptions, the original three-dimensional, geometrically nonlinear beam problem is rigorously split into a two-dimensional cross-sectional analysis and a one-dimensional global beam analysis, taking advantage of the geometric small parameter that is an inherent property of the structure.

The thermal problem of composite beams is studied first. According to the quasisteady theory of thermoelasticity, two beam models are proposed: one for heat conduction analysis and the other for thermoelastic analysis. For heat conduction analysis, two different …

Under What Conditions Do Community Demographics Influence Aggregate Recycling?, Edward Kotter

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Tons of household waste go to landfills throughout the western United States each year. Recycling has been a popular way for cities to extend the life of landfills by decreasing the amount of waste entering them. The development and implementation of recycling programs has not come without challenges. People recycle or do not recycle for different reasons. Much research has been done to understand who recycles, who does not recycle, and what recycling program characteristics elicit greater participation. This study adds to the existing body of literature by focusing on determinants of community-level recycling in the western United States. This …

Have Introduced Brown Trout (Salmo Trutta) Affected Native Aquatic Vertebrates In Western United States Streams?, Nora K. Burbank

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The introduction of exotic species to areas outside of their native range is one of the greatest threats to the biodiversity of native freshwater organisms. Exotic species have outcompeted native species for resources such as food and shelter, and in some cases these interactions have resulted in local extinctions or reductions in abundance of those native species. Brown trout are native to Eurasia, but have been introduced to much of the rest of the world, including the United States. In some parts of their introduced range, brown trout have substantially reduced the abundance and home ranges of some native fish …

Optimization Of Dissolved Air Flotation For Algal Harvesting At The Logan, Utah Wastewater Treatment Plant, Andrew R. Elder

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Research being completed at the Logan, UT wastewater treatment plant could provide a locally-sourced gasoline replacement by collecting algae that grows naturally. This process would also provide the City of Logan with a method to meet certain standards set by the state of Utah.

Problem and proposed solution:

The water leaving Logan’s wastewater treatment plant has high levels of phosphorus and nitrogen, two elements that are found in all wastewater treatment plants. These two substances need to be controlled, because they kill fish and cause pond scum to grow in recreational reservoirs downstream. A unique method has been found to …

Characterizing Water And Nitrogen Dynamics In Urban/Suburban Landscapes, Hongyan Sun

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research investigated the water use of different plant types in urban landscapes, nitrogen (N) and water transport in turf, and potential N leaching from urban landscapes to ground water. In the first study, three landscape treatments integrating different types of plants—woody, herbaceous perennial, turf—and putative water use classifications—Mesic, Mixed, Xeric—were grown in large drainage lysimeters. Each landscape plot was divided into woody, turf, and herbaceous perennial plant hydrozones and irrigated for optimum water status over two years, with water use measured using a water balance approach. For woody plants and herbaceous perennials, canopy cover, rather than plant type or …

Evaluation Of An Incompressible Energy-Vorticity Turbulence Model For Fully Rough Pipe Flow, Doug F. Hunsaker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Traditional methods of closing the Boussinesq-based Reynolds-averaged Navier-Stokes equations are considered, and suggestions for improving two-equation turbulence models are made. The traditional smooth-wall boundary conditions are shown to be incorrect, and the correct boundary conditions are provided along with sample solutions to traditional models. The correct boundary condition at a smooth wall for dissipation-based turbulence models is that which forces both the turbulent kinetic energy and its first derivative to zero. Foundations for an energy-vorticity model suggested by Phillips are presented along with the near-smooth-wall behavior of the model. These results show that at a perfectly smooth wall, the turbulent …

Latency As A Dependent Variable In Trial-Based Functional Analysis, Elizabeth Dayton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The following research project consisted of two parts. The first was a data analysis of previously collected data. The second was conducted in local public schools at no cost to the teachers, students, or schools. Many individuals with disabilities engage in aberrant behaviors that negatively affect their lives and the lives of those around them. The following research paper examined a tool currently being used in schools (trial-based functional analysis; FA) to determine its effectiveness at identifying the function of an individual’s behavior.

The trial-based FA is an assessment tool that is accessible to classroom teachers to help them identify …

Effect Of Vegetation On The Accumulation And Melting Of Snow At The Tw Daniels Experimental Forest, Vinod Mahat

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Snow melt is an important component of Western US water resources, accounting for about 50-80% of the annual runoff. Water resources management requires prediction of runoff from snowmelt accounting for the variability of vegetation present in heterogeneous watersheds. This dissertation has examined ways to improve snowmelt modeling capability to better account for vegetation canopy effects on snowmelt and has presented enhancements to an energy balance model that include i) an improved representation of the transmission of radiation through the canopy, ii) an improved representation of the atmospheric transport of heat and water vapor between the snow on the ground, in …

Axisymmetric Finite Element Modeling Of Adhesive Joint Between A Laminated Composite And Metal Cylinder, Casey A. Talbot

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Because lowering weight as much as possible is desirable in all applications designed to go to space, the use of composite materials is desirable. Composites are materials that are made up of two or more separate materials usually with significantly different characteristics which remain separate and distinct in their completed state. Fiber-reinforced epoxy composites, in general, are very strong and light. Because most space structures cannot solely be made of composites, a method to join them with metals is needed. Adhesive joining, or gluing, has been determined to be the most promising option.

For the joining technique to be used, …

Inkjet-Printed Highly Transparent Solar Cell Antennas, Jesus A. Arellano

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Small satellites, especially Cube Satellites (CubeSats), have become important vehicles for space exploration. One of the challenges CubeSats face is limited surface area. This limitation poses a question for antenna design–where to mount the antenna? Transparent antenna is a solution to resolve the competition between solar cells and antennas for surface area. The transparent antennas can be directly integrated on top of solar cells without requiring additional space. It is for this reason that this thesis focuses on the integration of highly transparent meshed antenna with solar cells. Even though transparent antennas allow light to travel light through them, they …

Predictive Modeling And Analysis Of Student Academic Performance In An Engineering Dynamics Course, Shaobo Huang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Engineering dynamics is a fundamental sophomore-level course required for many engineering students. This course is also one of the most challenging courses in which many students fail because it requires students to have not only solid mathematical skills but also a good understanding of dynamics concepts and principles.

The overall goal of this study was to develop a validated set of mathematical models to predict student academic performance in an engineering dynamics course taught in the College of Engineering at Utah State University. The predictive models will help the instructor to understand how well or how poorly the students in …

A Comparison Of Caregiver Report And Performance-Based Measures Of Functional Ability In Dementia: An Examination Of Moderating Variables, Christine M. Snyder

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study examined the association between data collection techniques used to measure functional abilities in individuals with dementia. Cognitive, functional, and behavioral data were collected through the Cache County Dementia Progression Study for individuals with dementia and their caregivers. The caregivers’ reports of care recipients’ functional status were compared with the care recipients’ scores on a performance-based measure of functional abilities. Analyses showed moderate correlation between caregivers’ reports and objective measures, with no significant effect of caregiver demographic or mental health factors. However, care recipients’ sensory motor impairments reduced the association between the two assessment methods.

Visits occurred at the …

Managing Water Shortages In The Weber Basin Using The Water Evaluation And Planning (Weap) System, Bereket K. Tesfatsion

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Water is a scarce natural resource while the demand for water grows constantly. In Utah, most of the water resources have already been developed. In addition, Utah is prone to drought events and the effects of climate change may exacerbate the already dire situation. Hence, managing this scarce resource efficiently is very important in meeting the growing demand.

Reservoirs are used to store water which is subsequently released to meet demands. For management purposes, reservoirs have different zones such as flood control zone, conservation zone, buffer zone and inactive zone. Water is normally released from the conservation zone. The water …

Effects Of High-Interest Writing Prompts On Performance Of Students With Learning Disabilities By, Kelsey J. Chlarson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The following study was done to examine the extent to which high-interest narrative writing prompts for 12- to 13-year old students in special education increase accuracy and total words written (TWW) in a 3-min timed writing sample compared to low-interest writing prompts.

Students who will participate will be individuals from a sixth- and seventh-grade special education language arts class who have been classified with LD. In this study, participants select high-interest writing prompts as story starter topics as preferred prompts for writing tasks. Initially, participants will select high- and low-interest writing topics using a prompt selection procedure. Given 40 potential …

An Assessment Of Vegetation Metrics And Plot Types To Measure Seasonal Variation And Grazing Effects On Riparian Plant Communities, Caroline M. Laine

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Monitoring changes in vegetation is important on public lands. Observing how plant communities respond to changes in land management can give insightful information about which management practices are sustainable. Because water is scarce in the western United States, many land managers focus their monitoring efforts along streams. However, monitoring streamside vegetation is challenging due to a variety of factors and can be confounded by factors such as seasonal climate variation and management activities, like cattle grazing.

In vegetation assessment, there are a variety of measurements that are taken to glean valuable information. Some attributes of interest include how much vegetation …

The Potential For Growth In Foreign Direct Investment In The Horticultural Sector Of Armenia, Mikayel Khachatryan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study examines why foreign investors choose to invest in companies in Armenia and is specifically attempting to understand how to attract more investment into the fruit and vegetable companies of Armenia. Investment by foreigners in domestic companies is referred to as foreign direct investment of FDI. The research was completed by gathering information from foreign firms that are already investing in companies in Armenia. This was done by conducting a face-to-face questionnaire with business managers of these companies in Yerevan, Armenia during August and December of 2010. The information gathered from these interviews was used in a statistical analysis …

The Effects Of Early Identification And Intervention On Language Outcomes Of Children Born With Hearing Loss, Catherine A. Callow-Heusser

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study included a comprehensive review of the literature in which the effects of early identification of hearing loss and intervention on language outcomes were investigated. Previous reviews of studies were not comprehensive in their coverage and did not include a common measure for comparing results across studies. Without a more rigorous analysis of the primary research, conclusions drawn from these reviews are tenuous. The review of primary studies showed they exhibit many methodological problems including weak experimental designs, small sample sizes, attrition or questionable sample selection methods, differences in length of treatment and characteristics of the participants, and inadequate …

Assessment Of Colorado’S Wilderness Areas: Manager Perceptions And Remoteness Modeling, Gary D. Vaughn

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study assessed visitor use levels and resource and social conditions in wilderness areas across the State of Colorado using existing and collected spatial data. This is the first attempt to spatially assess wilderness conditions at the state level. A state-wide assessment of wilderness conditions allows local and regional managers to make informed regional decisions and to prioritize and direct their time and energy efficiently. This assessment clarifies the recreational use and impacts across the state. This study consists of two projects: 1) managers’ perceptions of the location and extent of resource and social condition problems; and 2) a geographic …

A Dynamic State Metabolic Journey: From Mass Spectrometry To Network Analysis Via Estimation Of Kinetic Parameters, Arockia Ranjitha Dhanasekaran

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The term "metabolism" refers to the chemical processes occurring in a living organism to convert the food consumed into the energy needed to maintain a living state. Metabolism consists of two states, namely, a dynamic state and a steady state. In the dynamic state, the rate of chemical conversion of a substance is proportional to the amount of substance available, whereas in the steady state this rate is constant and independent of the amount of substance present (Chapter 4 Figure 1). Like all other fields of engineering, metabolic engineering involves the analysis and synthesis of metabolism. Molecular biological tools for …

The Relationship Between Family Functioning, Family Resilience, And Quality Of Life Among Vocational Rehabilitation Clients, Kristi P. Openshaw

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

While there has been extensive research on the quality of life for people with disabilities, very little research has been conducted on the way in which families impact the quality of life of these individuals. This study focused on how family dynamics impact the quality of life for people with disabilities who are clients of state vocational rehabilitation agencies. Specifically, family flexibility and cohesion, as well as family resilience, were the independent variables; quality of life was the dependent variable.

It was found that family functioning and family resilience play an important role in the quality of life for people …

Attitudinal And Experiential Factors Of Interethnic Romantic Relationships Among Native American Emerging Adults, Merrill L. Jones

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Doctoral student in psychology at Utah State University, Merrill Jones, and his major advisor, professor and licensed clinical psychologist, Renee V. Galliher, surveyed a sample of Native American individuals in the 18- to 25-year-old range about their romantic relationship attitudes and experiences with ethnically-different dating partners. The survey measured the participants’ past dating experiences, with an emphasis on which social influences and individual characteristics might impact their current attitudes about choosing dating partners who are not Native American. The responses of the participants will also be analyzed to identify how these factors relate with the other factors, and which factors …

Orchard Floor Management, Marc A. Rowley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Managing fruit orchards involves both the management of the orchard trees, and the orchard floor. Orchard floor management is vital to tree health, yield and fruit quality. Current standard management practices include maintaining a vegetation free tree row and a grass-covered alleyway. This system effectively controls weeds and creates a favorable environment for the fruit trees. However, limitations to standard orchard floor practices are that the grass alleyway provides no nutrient benefit, and current practices do not readily lend themselves to organic management. Alternative in-row and alleyway systems are requisite to creating improved orchard floor management systems.

Three different approaches …