Physical Sciences and Mathematics Commons^™

Carbon Sequestration On Utah Rangelands: A Landowner Perspective, Seth Cook

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Carbon sequestration is the removal of carbon dioxide from the air and storing it in plants and soil through natural processes. Rangelands can be managed to sequester carbon and mitigate climate change. Supported by the Utah Agricultural Experiment Station, this study assessed Utah rangeland owners’ perceptions of carbon sequestration and explored factors influencing their likelihood of participation in relevant programs. Data were collected through interviews and a statewide survey of Utah rangeland owners. Over two-thirds of respondents were aware of carbon sequestration and viewed it positively. Those who thought the climate had been changing over the past 30 years tended …

Robust Computational Tools For Multiple Testing With Genetic Association Studies, William L. Welbourn Jr.

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The mapping of the human genome and the completion of the Human HapMap project over the past decade have significantly altered how research is conducted with respect to the genetic epidemiology of human disease. Study designs and analytic approaches have evolved rapidly from investigations involving relatively few targeted candidate genes to hypothesis-free genome-wide association studies, where thousands – and now even millions – of single molecular mutations are simultaneously analyzed to identify regions of the genome that may influence disease. As laboratory techniques continue to improve and costs decrease, the volume of genetic data will inexorably rise, and robust tools …

A 2d Finite Element/1d Fourier Solution To The Fokker-Planck Equation, Joseph Andrew Spencer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Plasma, the fourth state of matter, is a gas in which a significant portion of the atoms are ionized. It is estimated that more than 99% of the material in the visible universe is in the plasma state. The process that stars, including our sun, combine atomic nuclei and produce large amounts of energy is called thermonuclear fusion. It is anticipated future energy demands will be met by large terrestrial devices harnessing the energy of nuclear fusion. A gas hot enough to produce the number of atomic collisions needed for fusion is necessarily in the plasma state. Therefore, plasmas are …

Production Of Biodiesel From Oleaginous Organisms Using Underutilized Wastewaters, Valerie Godfrey

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As part of the BioEnergy Team at Utah State Univeristy, my research objectives have been centered around the common theme of innovating new methods and
technology for producing biological compounds and, by means of chemical conversion and/or extraction, isolating new forms of biodiesel available for transportation fuel.
Within the broad scope of this project, I focused on the replacement of freshwater in cultivating such biological systems with wastewaters. If accomplished and correctly
applied, such research would reduce the environmental impact of biodiesel production by reducing the demand for freshwater. It also would reduce production costs by reducing the amount of …

Test Case Generation Using Combinatorial Based Coverage For Rich Web Applications, Chad Maughan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Web applications are increasingly moving business and processing logic from the server to the browser. Traditional, multiple-page request/response applications are quickly being replaced by single-page applications where complex application logic is downloaded on the initial page load and data is then subsequently fetched asynchronously via the browser's native XMLHttpRequest (XHR) object.

These new generation web applications are called Rich Web Applications (RWA). Frameworks such as the Google Web Toolkit (GWT), and JavaScript model-view-controller (MVC) frameworks such as Backbone.js are facilitating this move. With this migration, testing frameworks need to follow the logic by moving analysis and test generation from the …

Instances Of Conflict And Cooperation: An Exploration Into The Role Of Competition Between Usda-Wildlife Services And Wildlife Control Operators, Gary J. Bezzant Jr.

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In early 1994 the United States Department of Agriculture’s Animal Damage Control agency implemented a directive providing guidance to help avoid competition between themselves and private businesses, known as Wildlife Control Operators (WCOs) engaging in similar work. Nearly two decades later some WCOs still complain about having to compete with the Animal Damage Control agency, now named Wildlife Services. Other businesses report enjoying a cooperative relationship with the agency.

I analyzed four policies that regulate competition between Wildlife Services and WCOs and found that there is a good amount of guidance given to Wildlife Services in regards to their competitive …

Combinatorial-Based Prioritization For User-Session-Based Test Suites, Schuyler Manchester

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Software defects caused by inadequate software testing can cost billions of dollars. Further, web application defects can be costly due to the fact that most web applications handle constant user interaction. However, software testing is often under time and budget constraints. By improving the time efficiency of software testing, many of the costs associated with defects can be saved.

Current methods for web application testing can take too long to generate test suites. In addition, studies have shown that user-session-based test suites often find faults missed by other testing techniques. This project addresses this problem by utilizing existing user sessions …

A Localized Geometric-Distortion Resilient Digital Watermarking Scheme Using Two Kinds Of Complementary Feature Points, Jiyuan Wang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

More and more digital images are being distributed over the Internet to an evergrowing number of people for sharing, studying, or other purposes. However, most of those digital products are exposed without any protection, and such information can be easily transferred, copied, and tampered without authorization simply by using readily available digital multimedia editing software. Digital watermarking techniques have been developed as a tool to discriminate whether the original content of digital media is tampered or not. A digital watermark is embedded on digital images as an invisible message and is used to demonstrate the proof by the owner.

In …

Environmental Assessment Of Streams: Linking Land Use, Instream Stressors, And Biological Indices To Infer Likely Causes Of Ecological Impairment, Jacob J. Vander Laan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

To protect and restore stream biota, managers need to be able to both detect biological degradation and infer likely causes of impairment. Managers commonly develop indices based on stream biota to assess the biological condition of streams. However, the performance of these indices dictates the ability to detect degradation, and although index performance varies widely, the sources of this variation are often unclear. In addition, bioassessments do not identify causes of impairment. My thesis research had two general goals: 1) develop indices to measure biological condition in Nevada streams and 2) quantify relationships between land uses, stressors, and biological condition …

Structural And Mechanistic Investigations Of Phosphothreonine Lyase Class Of Enzymes, Alok Gopalkrishna Shenoy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Phosphorylation and dephosphorylation are a highly pervasive mechanism in biology that is used by the cell to modulate enzymes and proteins. The presence of a phosphate group can activate or deactivate an enzyme. The phosphate group is linked to a protein by a phosphoester bond that is known to be highly stable in cytoplasmic pH range. Thus the breaking and formation of these bonds need to be effected by enzymes.

Recent discovery of the activity carried out by certain virulence related proteins (OspF released by Shigella and SpvC released by Salmonella) have resulted in a necessity to create a new …

Adaptive Re-Segmentation Strategies For Accurate Bright Field Cell Tracking, Nare Hayrapetyan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Cell migration is central for many fundamental biological processes and development of multi-cellular organisms. The failure of cells to migrate or migration of cells to inappropriate locations during embryo development can result in life threatening consequences such as brain malfunctions. In adults, cell migration plays an important role in wound healing and immune responses. Failure in these processes can have dramatic medical implications and can lead to vascular diseases and tumor formation. Therefore, studying cell migration is critical to helping prevent and cure diseases.

Cell migration is usually studied by observing cells photographed through a microscope at regular time intervals. …

Factors Influencing The Distribution Of Brown Trout (Salmo Trutta) In A Mountain Stream: Implications For Brown Trout Invasion Success, Christy Meredith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Brown trout (Salmo trutta), one of the world’s most successful introduced species in river and lake systems, negatively impacts native species through predation, competition, and systemwide effects. Thus, there is a need to understand factors controlling the distribution of brown trout, in order to prioritize and develop conservation and management strategies. Within the context of invasion success, I investigated how the physical characteristics of the Logan River influence the distribution of brown trout, as well as the potential for brown trout predation on a native fish, the mottled sculpin (Cottus bairdi).

In chapter 1, I evaluated …

Sustainable Ski Resorts In The State Of Utah: Working Toward The Future, Andrew Call

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Utah State University Extension branch funded a research project designed to meet an identified need and create a baseline in knowledge of the implementation of environmentally sustainable practices among Utah ski resorts. Because of the potential impacts of climate change and unsustainable practices that negatively impact both the biophysical and human/cultural aspects of these environments, the ski resort industry is facing an uncertain future both environmentally and economically. However, very little is known about this issue, or how to address it. Collecting baseline information on the subject of environmental sustainability amongst Utah area ski resorts is crucial to ensure …

Comparison Of Saber Oh Measurements To Rocket Photometry Data, Jordan Rozum, Gene A. Ware, Doran J. Baker

Browse All Undergraduate research

No abstract provided.

Micrometeoroid From Misse Examined To Understand The Effects Of The Space Environment On Space Suit Materials, Kelby T. Peterson

Student Showcase

Samples that were part of the Materials International Space Station Experiment (MISSE) experienced varying effects whilst exposed to the space environment; perhaps the most intriguing effect was the crater created by a micrometeoroid impact into a thin film of Vapor Deposited Aluminum (VDA) coated Mylar. Approximately 180 samples of various materials used in space-component design were flown on MISSE-6 and spent 18 months suspended off the side of the International Space Station. The Utah State University SUSpECS project was a unique student experiment that allowed for pre- and post-flight analysis of these material samples which were returned in pristine condition …

Leaf Area And Structural Changes After Thinning In Even-Aged Picea Rubens And Abies Balsamea Stands In Maine, Usa, R. Justin Derose, Robert S. Seymour

Wildland Resources Faculty Publications

We tested the hypothesis that changes in leaf area index (LAI m2 m−2) and mean stand diameter following thinning are due to thinning type and residual density. The ratios of pre- to postthinning diameter and LAI were used to assess structural changes between replicated crown, dominant, and low thinning treatments to 33% and 50% residual density in even-aged Picea rubens and Abies balsamea stands with and without a precommercial thinning history in Maine, USA. Diameter ratios varied predictably by thinning type: low thinnings were 0.7 but 1.0 . LAI change was affected by type and intensity of thinning. On average, …

Electron Energy Dependent Charging Effects Of Multilayered Dielectric Materials, Gregory Wilson, Jr Dennison, Amberly Evans Jensen, Justin Dekany

Presentations

No abstract provided.

Observations With The Most Sensitive Rayleigh-Scatter Lidar, Leda Sox, Vincent B. Wickwar, Joshua P. Herron, Marcus J. Bingham

Graduate Student Posters

The mesosphere is the most unexplored region of the atmosphere. Its altitude range of 50-85 km lies in between the reaches of data collecting instruments like weather balloons and satellites. For this reason, remote sensing systems, such as lidar, which are able to employ ground-based instruments to make extensive measurements in this difficult to detect region. The Rayleigh-scatter lidar at USU is currently being redeveloped to be the most powerful and sensitive of its kind. This type of lidar exploits light and particle interactions, like those that account for the blue color of the sky, to make relative density and …

The Glass Is Half-Full: Overestimating The Quality Of A Novel Environment Is Advantageous, Oded Berger-Tal, Tal Avgar

Wildland Resources Faculty Publications

According to optimal foraging theory, foraging decisions are based on the forager's current estimate of the quality of its environment. However, in a novel environment, a forager does not possess information regarding the quality of the environment, and may make a decision based on a biased estimate. We show, using a simple simulation model, that when facing uncertainty in heterogeneous environments it is better to overestimate the quality of the environment (to be an “optimist”) than underestimate it, as optimistic animals learn the true value of the environment faster due to higher exploration rate. Moreover, we show that when the …

Micrometeoroids From Misse Examined To Understand The Effects Of The Space Environment On Space Suit Materials, John R. Dennison

All Physics Faculty Presentations

Samples that were part of the Materials International Space Station Experiment (MISSE) experienced varying effects whilst exposed to the space environment; perhaps the most intriguing effect was the crater created by a micrometeoroid impact into a thin film of Vapor Deposited Aluminum (VDA) coated Mylar. Approximately 180 samples of various materials used in space-component design were flown on MISSE-6 and spent 18 months suspended off the side of the International Space Station. The Utah State University SUSpECS project was a unique student experiment that allowed for pre- and post-flight analysis of these material samples which were returned in pristine condition …

The Effects Of Space Environment On Wireless Communication Devices' Performance, Hillyard Landon, Jr Dennison

Posters

This project evaluates the effects of the space environment on small radio hardware devices called Bluetooth (a proprietary open wireless technology standard for exchanging data over short distances) chips (hoovers). When electronics are exposed to the harsh environment outside the Earth's atmosphere, they sometimes do not perform as expected. The USU Getaway Away Special (GAS) team is now in the design stages of launching a CubeSat (a 10 cm cubed autonomous satellite to fly in Low Earth Orbit). In order to conduct experiments proposed for the USU GAS Cubesat, Bluetooth wireless communication will be used. By testing commercially available hardware …

The Effect Of Space Environment On Wireless Communication Devices' Performance, Landon Hillyard, Jr Dennison

Presentations

No abstract provided.

Simulation Chamber For Space Environment Survivability Testing, Lisa Montierth, Robert H. Johnson, Jr Dennison, James S. Dyer

Presentations

No abstract provided.

Micrometeoroid From Misse Examined To Understand The Effects Of The Space Environment On Space Suit, Kelby Peterson, Jr Dennison

Presentations

No abstract provided.

Electric Field Dependence Of The Time To Electrostatic Breakdown In Insulating Polymers, Charles Sim, Alec Sim, Jr Dennison

Presentations

No abstract provided.

Low Earth Orbiting Photographer (Leop) Cube Satellite, Jan J. Sojka, J. Alex Landon

Posters

The exploration and study of space is critical for the future of our society, but the opportunities for educational institutions to get involved in space research have faded dramatically in the last decade with the retirement of the space shuttle program. The USU Get Away Special (GAS) team is designing a new, low cost solution to space research, CubeSat (Cube Satellite). This small satellite, with a volume of approximately one liter, will have a high resolution camera directed at earth, and students will be able to request a picture of their area when the satellite flies overhead. In this way, …

Electric Field Dependence Of The Time To Electrostatic Breakdown In Insulating Polymers, Alec Sim, John R. Dennison

All Physics Faculty Presentations

Electrostatic breakdown can be thought of as the point at which a buildup of local defects in insulators leads to a catastrophic change in electrical conductivity. Defects can be produced by temperature, radiation, or a prolonged exposure to constant electric fields. The endurance time is the time it takes to generate enough defects to create a conduction path for electric current to flow more readily. The literature for electrostatic breakdown in polymeric highly disordered insulating materials discusses two competing theories for electrostatic breakdown, based on generation of either recoverable defects or irrecoverable defects. Such defects in the polymer chains can …

Simulation Chamber For Space Environment Survivability Testing, Lisa Montierth, Robert H. Johnson, John R. Dennison, James Dyer

All Physics Faculty Presentations

A vacuum chamber was designed and built that simulates the space environment making possible the testing of material modification due to exposure of solar radiation. Critical environmental components required include an ultra high vacuum (10-9 Torr), a UV/VIS/NIR solar spectrum source, an electron gun and charge plasma, temperature extremes, and long exposure duration. To simulate the solar spectrum, a solar simulator was attached to the chamber with a range of 200nm to 2000nm. The exposure time can be accelerated by scaling the solar intensity up to four suns. A Krypton lamp imitates the 120 nm ultraviolet hydrogen Lymann alpha emission …

Low Temperature Cathodoluminescence In Disordered Sio2, Amberly Evans, Gregory Wilson, John R. Dennison

All Physics Faculty Presentations

Disordered SiO2 is commonly used for optical instrumentation and coatings. In space telescope applications, these materials can be exposed to low temperature (particularly for IR telescopes) and simultaneous electron fluxes from the space plasma environment. During recent charging tests of this dielectric material, a discernable glow was detected emanating from the surface of the SiO2, indicating that the incident electron beam induced a luminescent effect, termed cathodoluminescence. As the sample cooled from 300 K to 120 K, a change in the intensity and energy spectrum of the glow was observed between 250 nm and 1700 nm, demonstrating that the SiO2 …

Electric Field Dependence Of The Time To Electrostatic Breakdown In Insulating Polymers, Charles Sim, Alec Sim, Jr Dennison

Presentations

No abstract provided.