Physical Sciences and Mathematics Commons^™

Pulse-Laser Infrared Photothermal Spectrometry Of Condensed-Phase Aerosols Based On Photothermal Deflection Spectroscopy, Oluwatosin Olubunmi Dada

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The research reported in this dissertation is aimed at development of photothermal deflection detector that is consistent with constraints imposed by aerosols sampling and analysis. The main objectives of this project are: 1) the design and evaluation of initial apparatus prototypes and 2) a test of the prototype apparatus with surrogate substances using conventional mid-infrared gas lasers.

Experimental evaluation of reduced size photothermal apparatus is first performed with gaseous samples. Analysis of trichlorofluoromethane (CFC-11) and ethanol vapors is performed with both conventional large apparatus and the prototype small apparatus. Comparison studies in terms of photothermal signal from both apparatuses are …

The Process Of Tracking In Mathematics In Box Elder School District, Megan Haramoto Bushnell

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Educational policymakers have used tracking to instruct students in a variety of subjects, including mathematics. Tracking, which has also been called ability grouping, is a process by which students in the same grade are placed into different classes based on academic ability. Few educators and sociologists have looked at the process by which students are placed in different mathematics tracks. The research design of this study focused on accumulating, evaluating, and reporting the understanding and observations of 12 teachers and 4 counselors as they discussed their knowledge and involvement in the mathematics placement procedures from the intermediate and middle school …

Intergranular Phases In Cyclically Annealed Yba2cu3o7-X And Their Implications For Critical Current Densities, Andrew Peter Clarke

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

We report changes in the intergranular material and grain morphology of YBa₂Cu₃O_7-x during cyclic anneals between 780 and 980 ºC in oxygen at atmospheric pressure. Two endothermic reactions were detected: (a) the eutectic reaction of YBa₂Cu₃O_7-x with CuO and BaCuO₂ at 900 ºC (enthalpy ∆H_a) and (b) the peritectic reaction of YBa₂Cu₃O_7-x with CuO at 950 ºC (∆H_b). During the first anneal, only reaction (b) is detected, and although it should only occur if there is an excess of CuO, …

Approximations To Continuous Processes In Hierarchical Models, Amanda Cangelosi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Models for natural nonlinear processes, such as population dynamics, have been given much attention in applied mathematics. For example, species competition has been extensively modeled by differential equations. Often, the scientist has preferred to model the underlying dynamical processes (i.e., theoretical mechanisms) in continuous-time. It is of both scientific and mathematical interest to implement such models in a statistical framework to quantify uncertainty associated with the models in the presence of observations. That is, given discrete observations arising from the underlying continuous process, the unobserved process can be formally described while accounting for multiple sources of uncertainty ( …

Factors Related To Success And Participants’ Psychological Ownership In Collaborative Wildlife Management: A Survey Of Sage-Grouse Local Working Groups, Lorien R. Belton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Declines of sage-grouse (Centrocercus spp.) across the western United States have prompted the formation of numerous collaborative stakeholder partnerships, known as local working groups. These voluntary groups create and implement local sage-grouse management plans and projects, often in the hopes that their efforts may help avert a federal Endangered Species designation for the bird. Using a mail survey of participants in 54 local working groups, I examined the importance of psychological ownership in working group dynamics. Psychological ownership is conceptualized as a latent, multidimensional variable consisting of responsibility, control, and caring elements. Multiple regression analysis showed early-stage group success, representative …

Two Highly Diverse Studies In Computing: A Vitruvian Framework For Distribution And A Search Approach To Cancer Therapies, Brian G. Smith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Solid cancer tumors must recruit new blood vessels for growth and maintenance. Discovering drugs that block this tumor-induced development of new blood vessels (angiogenesis) is an important approach in cancer treatment. However, the complexity of angiogenesis and the difficulty in implementing and evaluating medical changes prevent the discovery of novel and effective new therapies. This paper presents a massively parallel computational search-based approach for the discovery of novel potential cancer treatments, using a high fidelity simulation of angiogenesis. Discovering new therapies is viewed as multi-objective combinatorial optimization over two competing objectives: minimizing the medical cost of the intervention while minimizing …

Development Of A Post-Fire Monitoring Protocol For Evaluating Treatment Effectiveness And Cheatgrass Abundance Using Quickbird Imagery And Ground Observations, Gabriel Bissonette

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Bureau of Land Management (BLM) manages 9.3 million hectares of land in Utah and has implemented an Emergency Stabilization and Rehabilitation (ESR) Program to protect life and property, combat soil erosion, and reduce the invasion of exotic/noxious weeds following wildland fire. In highly vulnerable sites, seeding treatments may be applied to establish an interim landcover to stabilize the soil and competitively exclude weed invasions. Monitoring treatment effectiveness is mandated through ESR guidelines and necessary for the submission of annual Accomplishment Reports for the first three years following fire containment. Ground monitoring has been the traditional approach to fulfilling this …

Perceived Crowding And Visitor Support For Use Rationing: A Reanalysis Of Existing Data, Jascha M. Zeitlin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis presents a reanalysis of data collected between 1999 and 2006 by the Institute for Outdoor Recreation and Tourism (IORT) at Utah State University. These data concern a variety of outdoor recreation sites in Utah, Idaho, and South Dakota, and were collected via intercept, mail, and, to a very limited extent, telephone surveys. Survey instruments contained questions related to visitor perceptions of crowding, overall satisfaction, support for use limits/rationing, and estimates of use density, in addition to other conceptually related factors.

Analyses consisted of multiple regression models for both perceived crowding and visitor support for use limits dependent variables …

The Adaptability Of Langmuir Probes To The Pico-Satellite Regime, Andrew Jay Auman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this thesis is to investigate whether it is feasible to use Langmuir probes on pico-satellites flying in low Earth orbit over mid- to low-latitude geographic regions. Following chapters on the expected ionospheric conditions and an overview of Langmuir probe theory, a chapter addressing the difficulties involved with pico-satellite Langmuir probes is presented. Also, the necessary satellite-to-probe surface area requirements in order to achieve confidence in pico-satellite Langmuir probe data, for the orbital regions of interest to this thesis, are stated.

Understanding Unfolding Change And The Value Of Strategic Unification In Recent Usu Information Technology Functional Realignment, Eric S. Hawley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This is a qualitative case study of the 2005-2008 Utah State University Information Technology reorganization from the perspective of key change advocates. The study identified and documented the unfolding change process involved in the reorganization in terms of dissatisfaction, executive changes, internal executive strategic planning, implementation and initial impacts, and continuous "in situ" strategic planning. The study also answered a set of supporting concluding questions indicating increased value to the institution in areas of customer service and confidence, organization, financial resources, planning and policy, security, and increased/improved services and service functions.

Synthetic Complexes Of Relevance To Ni(Ii)-Containing Enzymes, Katarzyna Rudzka

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The work outlined herein presents an investigation of synthetic model complexes of relevance to the active sites of Ni(II)-containing enzymes, particularly urease, glyoxalase I, and acireductone dioxygenase. The research focuses on studying the structural and reactivity features of nickel complexes with biologically relevant substrates. The anion of acetohydroxamic acid is a well-known inhibitor of urease enzymes, including those isolated from Klebsiella aerogenes and Bacillus pasteurii. A precursor to the acetohydroxamate coordination in ureases is proposed to be an interaction between Ni(II) and acetohydroxamic acid. By using a novel supporting chelate ligand capable of secondary hydrogen bonding interactions a novel …

A Novel Authentication And Validation Mechanism For Analyzing Syslogs Forensically, Steena D.S. Monteiro

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research proposes a novel technique for authenticating and validating syslogs for forensic analysis. This technique uses a modification of the Needham Schroeder protocol, which uses nonces (numbers used only once) and public keys. Syslogs, which were developed from an event-logging perspective and not from an evidence-sustaining one, are system treasure maps that chart out and pinpoint attacks and attack attempts. Over the past few years, research on securing syslogs has yielded enhanced syslog protocols that focus on tamper prevention and detection. However, many of these protocols, though efficient from a security perspective, are inadequate when forensics comes into play. …

Extending F10.7'S Time Resolution To Capture Solar Flare Phenomena, Ariel O. Acebal

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Solar ultraviolet (UV) radiation ionizes the neutral components in the atmosphere, which is partly responsible for the formation of the ionosphere, and contributes to heating of the atmosphere. Solar flares change the solar spectrum at times by several orders of magnitude. These changes modify the Earth's upper atmosphere, causing problems to communication systems and space operations, such as increased satellite drag. Unfortunately, solar UV measurements are limited since they can only be observed with space-based sensors. In order to work around this limitation, the solar radio emissions at a wavelength of 10.7 cm have been used as a proxy for …

Darboux Integrability Of Wave Maps Into 2-Dimensional Riemannian Manifolds, Robert Ream

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The harmonic map equations can be represented geometrically as an exterior differential system (EDS), ε. Using this representation we study the harmonic maps from 2D Minkowski space into 2D Riemannian manifolds. These are also known as wave maps. In this case, E is invariant under conformal transformations of Minkowski space. The quotient of ε by these conformal transformations, E/G, is an s=0 hyperbolic system.

The main result of our study is that the prolonged EDS, ε^(k), is Darboux integrable if and only if the prolonged quotient EDS, ε^(k+1), is Darboux integrable. We also find invariants determining …

Threat Perception As A Determinant Of Pro-Environmental Behaviors: Public Involvement In Air Pollution Abatement In Cache Valley, Utah, Joshua D. Marquit

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Threat perception related to environmental issues such as air pollution may be a determinant of pro-environmental behaviors. Among the potential threats of air pollution, include the perceived impacts on the psychological, social, and economic wellbeing of a community. Because of rapid increases in population growth, urbanization, and the mountainous landscapes, the American West is extremely susceptible to the adverse impacts of air pollution.

A secondary data analysis was conducted using data from the Air Quality Perception Survey conducted in Cache County, Utah. The survey focused on the public perception of air pollution in Cache County and perceived impact on personal …

Strides Towards Better Application Security, Sathyaraj Balasubramanian

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Static analysis tools analyze source code for vulnerabilities. However, these types of tools suffer from various problems that limit their effectiveness. This thesis examines these static analysis tools and suggests techniques for making them more efficient at detecting different types of vulnerabilities.

The thesis further analyzes possible causes for these vulnerabilities by examining the source code written by programmers of various categories. Finally, this thesis discusses solutions and techniques to improve general security awareness as well as the importance of secure coding among the students and software developers.

A C To Register Transfer Level Algorithm Using Structured Circuit Templates: A Case Study With Simulated Annealing, Jonathan D. Phillips

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A tool flow is presented for deriving simulated annealing accelerator circuits on a field programmable gate array (FPGA) from C source code by exploring architecture solutions that conform to a preset template through scheduling and mapping algorithms. A case study carried out on simulated annealing-based Autonomous Mission Planning and Scheduling (AMPS) software used for autonomous spacecraft systems is explained. The goal of the research is an automated method for the derivation of a hardware design that maximizes performance while minimizing the FPGA footprint. Results obtained are compared with a peer C to register transfer level (RTL) logic tool, a state-of-the-art …

Impact Analysis Of System And Network Attacks, Anupama Biswas

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Systems and networks have been under attack from the time the Internet first came into existence. There is always some uncertainty associated with the impact of the new attacks. Compared to the problem of attack detection, analysis of attack impact has received very little attention. Generalize and forecasting the kind of attack that will hit systems in future is not possible. However, it is possible to predict the behavior of a new attack and, thereby, the impact of the attack. This thesis proposes a method for predicting the impact of a new attack on systems and networks as well as …

Agent-Organized Network Coalition Formation, Levi L. Barton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis presents work based on modeling multi-agent coalition formation in an agent organized network. Agents choose which agents to connect with in the network. Tasks are periodically introduced into the network. Each task is defined by a set of skills that agents must fill. Agents form a coalition to complete a task by either joining an existing coalition a network neighbor belongs to, or by proposing a new coalition for a task no agents have proposed a coalition for. We introduce task patience and strategic task selection and show that they improve the number of successful coalitions agents form. …

Optimal Irrigation Management For Sloping, Blocked-End Borders, Jorge Jose Escurra

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A robust mathematical model of one-dimensional flow for sloping, blocked-end border irrigation was developed using the four-point implicit method to solve the Saint-Venant equations, the volume-balance solution method, and the implementation of new algorithms to avoid numerical instability and solution divergence. The model has the capability of successfully simulating all surface irrigation phases in blocked-end borders for a range of inflow rates (0.01 - 0.05 m³/s per m), longitudinal slopes (up to 1.00%), and border lengths (100 - 500 m).

To achieve numerical stability over the specified parameter ranges, the model was divided into three parts: (1) advance-phase …

Decadal-Scale Changes On Coral Reefs In Quintana Roo, Mexico, Thaddeus Allen Nicholls

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In 1988 data on coral reef community composition were collected from two areas, Akumal and Chemuyil, Quintana Roo, Mexico, ranging from 5-35m depth. These areas were revisited in 2005 and data were collected by the same methods and at the same depths as in 1988. Data from 1988 and 2005 were compared to determine if the coral reefs had undergone significant changes, and what specific changes had occurred. Chi-square analysis determined that community composition data collected in 1988 are significantly different from data collected in 2005 at all sites and depths within the categories of corals, gorgonians, sponges, and macroalgae. …

Sources And Source Processes Of Organic Nitrogen Aerosols In The Atmosphere, Mark E. Erupe

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The research in this dissertation explored the sources and chemistry of organic nitrogen aerosols in the atmosphere. Two approaches were employed: field measurements and laboratory experiments. In order to characterize atmospheric aerosol, two ambient studies were conducted in Cache Valley in Northern Utah during strong winter inversions of 2004 and 2005. The economy of this region is heavily dependent on agriculture. There is also a fast growing urban population. Urban and agricultural emissions, aided by the valley geography and meteorology, led to high concentrations of fine particles that often exceeded the national ambient air quality standards. Aerosol composition was dominated …

Discriminating Between Biological And Hydrological Controls Of Hyporheic Denitrification Across A Land Use Gradient In Nine Western Wyoming Streams, Andrew Kenneth Myers

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I studied nine streams near Grand Teton National Park, Wyoming, covering a land use gradient (urban, agricultural, and forested) to assess influences of land use on denitrification rates and hyporheic exchange. I hypothesized denitrification in the hyporheic zone is governed by availability of chemical substrates and hydrologic transport. I tested this hypothesis by coupling measurements of denitrification potentials in hyporheic sediments with a 2-storage zone solute transport model. Denitrification potentials were lowest on average in hyporheic sediments from forested streams and highest from agricultural streams. Modeling results suggest, on average, agricultural sites are transport-limited by having the slowest exchange rate …

A Post-Project Assessment Of The Provo River Restoration Project: Channel Design, Reconfiguration, And The Re-Establishment Of Critical Physical Processes, Randy Ray Goetz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A physical assessment of the Provo River Restoration Project was undertaken in order to determine how alterations to the channel were designed, the nature of as-built channel morphology, and the performance of the reconfigured channel in terms of achieving frequent (2-year recurrence) bankfull discharge and increasing transient storage. Measures of channelized and reconfigured channel morphology were obtained using total station survey, digital aerial photography, and pebble counts. Results of geomorphic analysis were compared with similar measurements made by a regional consulting company, and stream channel design data, in order to determine that intended mitigation included reducing channel capacity, increasing sinuosity, …

Small Sample Methods For The Analysis Of Clustered Binary Data, Lawrence J. Cook

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

There are several solutions for analysis of clustered binary data. However, the two most common tools in use today, generalized estimating equations and random effects or mixed models, rely heavily on asymptotic theory. However, in many situations, such as small or sparse samples, asymptotic assumptions may not be met. For this reason we explore the utility of the quadratic exponential model and conditional analysis to estimate the effect size of a trend parameter in small sample and sparse data settings. Further we explore the computational efficiency of two methods for conducting conditional analysis, the network algorithm and Markov chain Monte …

Algorithm Development For Column Water Vapor Retrieval Using The Sun And Aureole Measurement (Sam) Sensor, Joshua Bruce Williams

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

To understand and model the energetics of the Sun-Earth connection, measurements of specific atmospheric molecules are beneficial. The objective is to formulate an algorithm to derive temporally varying atmospheric water vapor concentrations as functions of altitude, latitude, and longitude from solar irradiance absorption measurements. The Visidyne SAM (Sun and Aureole Measurement) instrument, which studies the size and distribution of cloud particles, was used to obtain the experimental data. By introducing a spectrometer to the SAM instrument, column water vapor is produced as part of the data product. A new model optimized algorithm is developed and tested versus existing algorithms. Through …

Impact Of Land-Applied Biosolids On Forage Quality And Water Movement During Rangeland Restoration Activities, Issaak R. Vasquez

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The land application of biosolids to provide nutrients and organic matter is widely practiced in agricultural applications. However, the potential benefit of applying biosolids to disturbed rangelands has not been adequately evaluated. Thus the main goal of the current study was to evaluate the potential economic and environmental benefits of applying biosolids to disturbed rangeland with the main focus on evaluating the impact on forage quality and quantity as a function of biosolids type and application rate. Three types of biosolids (aerobically, anaerobically, and lime stabilized biosolids) were surface applied with no subsequent tilling at various loading rates (1, 5, …

Algorithm Development Of The Aglite-Lidar Instrument, Christian Marchant

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Particulate emissions from agricultural operations are increasingly receiving attention from regulatory bodies as a potential source of air pollution. The Space Dynamics Laboratory (SDL) has developed the Aglite system, a suite of instruments including a lidar that is capable of measuring particulate emission levels from agricultural facilities. This system provides a novel method of measuring particulate mass (PM) pollution, allowing measurements to be taken of diverse types of facilities with high temporal and spatial resolution. This high resolution allows for the measurement of emission levels generated by specific activities, fostering the development and determination of best management practices.

The Aglite …

The Timing And Magnitude Of Channel Adjustments In The Upper Green River Below Flaming Gorge Dam In Browns Park And Lodore Canyon, Colorado: An Analysis Of The Pre- And Post-Dam River Using High-Resolution Dendrogeomorphology And Repeat Topographic Surveys, Jason S. Alexander

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Channel narrowing on the Green River in Utah and Colorado has been well documented by several authors and has been attributed to reductions in flow after 1930, the construction of Flaming Gorge Dam (FGD), and the invasion of the woody riparian plant Tamarisk (tamarix ramosissima). Narrowing has occurred through the deposition of inset floodplains, which have vertically accreted within a previously larger active channel. Prior to closure of FGD, lower magnitude floods aggraded surfaces in the areas of the channel that had the highest divergence in the velocity flow field (i.e. bars and banks). These surfaces later became …

The Geologic History Of Subsurface Arkosic Sedimentary Rocks In The San Andreas Fault Observatory At Depth (Safod) Borehole, Central California, Sarah D. Draper

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The aim of the San Andreas Fault Observatory at Depth (SAFOD) project, a component of the NSF Earthscope Initiative, is to directly observe active fault processes at seismogenic depths through the drilling of a 3 km deep (true vertical depth) inclined borehole across San Andreas fault. Preliminary subsurface models based on surface mapping and geophysical data predicted different lithologies than were actually encountered. At 1920 meters measured depth (mmd), a sequence of well-indurated, interbedded arkosic conglomerates, sandstones, and siltstones was encountered. We present a detailed lithologic and structural characterization as a step toward understanding the complex geologic history of this …