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Decadal-Scale Changes On Coral Reefs In Quintana Roo, Mexico, Thaddeus Allen Nicholls Dec 2008

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. …


Development Of Modular Thermal Control Architecture For Modular Satellites, Quinn Eric Young Dec 2008

Development Of Modular Thermal Control Architecture For Modular Satellites, Quinn Eric Young

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Research has been completed to determine the most effective thermal control architecture for modular satellites. This research investigated principles of modularity, modular spacecraft examples, thermal control methods, and advanced thermal control technologies. A modular spacecraft was designed as a case study to determine key influences and issues. A number of thermal control architectures were developed. Each was evaluated for compatibility with modularity principles, thermal control performance, and a realizable implementation. Thermal control performance was determined by simulating on-orbit conditions for a number of design reference missions, including traditional thermal control architecture used for comparison. An effective thermal control architecture was …


Distributed Control For Robotic Swarms Using Centroidal Voronoi Tessellations, Shelley Rounds Dec 2008

Distributed Control For Robotic Swarms Using Centroidal Voronoi Tessellations, Shelley Rounds

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis introduces a design combining an emerging area in robotics with a well established mathematical research topic: swarm intelligence and Voronoi tessellations, respectively. The main objective for this research is to design an economical and robust swarm system to achieve distributed control. This research combines swarm intelligence with Voronoi tessellations to localize a source and create formations. Extensive software coding must be implemented for this design, such as the development of a discrete centroidal Voronoi tessellation (CVT) algorithm.

The ultimate purpose of this research is to advance the existing Mobile Actuator and Sensor Network (MASnet) platform to eventually develop …


Evaluation Of Arrayed-Field Concentration Measurements And U. S. Epa-Regulatory Models For The Determination Of Mixed-Source Particulate Matter Emissions, Derek Jones Dec 2008

Evaluation Of Arrayed-Field Concentration Measurements And U. S. Epa-Regulatory Models For The Determination Of Mixed-Source Particulate Matter Emissions, Derek Jones

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

With the continued population growth and the blurring of the urban and rural interface, air quality impacts associated with agricultural particle-producing processes are becoming increasingly important. There is a lack of emission rate data from these source types and no prescribed measurement technique available to the agricultural and regulatory communities. One technique that has shown promise is combining field measurements with inverse modeling. This approach was used herein to examine particulate emissions from an almond harvesting operation, a cotton ginning facility, and comparative emissions from conservation versus conventional tillage practices. EPAapproved models ISCST3 and AERMOD were used with AirMetrics samplers. …


Experiments In Distributed Multi-Robot Coordination, Larry Dale Ballard Dec 2008

Experiments In Distributed Multi-Robot Coordination, Larry Dale Ballard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Consensus control algorithms for multi-agent systems are an area of much research. Several consensus control laws are experimentally validated on a multi-robot testbed in this thesis. A graphical user interface (GUI) is developed that simplies use of the testbed, as well as allows the execution of the testbed programs to be divided across multiple computers. This not only provides a more powerful computing environment, but a more realistic communication environment for the testbed. A method for a time varying or dynamic formation is both proposed and experimentally validated on the testbed. This research also explores a method for dynamic group …


The Adaptability Of Langmuir Probes To The Pico-Satellite Regime, Andrew Jay Auman Dec 2008

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.


Effective Practices Of Project Lead The Way Partnership Teams, Cody J. Reutzel Dec 2008

Effective Practices Of Project Lead The Way Partnership Teams, Cody J. Reutzel

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to gather information from Project Lead The Way (PLTW) partnership team experts. This project follows the methodology of a modified Delphi study. A review of literature in the areas of curriculum development, pre-college engineering, and the Delphi research technique provided the background for the structure utilized. Top programs from across the country were questioned to identify and come to a consensus on top components essential to developing and utilizing a successful PLTW partnership team. The components were categorized into two lists: effective practices utilized to make a program successful and effective practices employed by …


Design Of Tunable Edge-Coupled Microstrip Bandpass Filters, Srinidhi V. Kaveri Dec 2008

Design Of Tunable Edge-Coupled Microstrip Bandpass Filters, Srinidhi V. Kaveri

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis is a study of tunability of edge-coupled filters. Microstrip edge-coupled bandpass filters are planar structures and have advantages such as easy design procedures and simple integration into circuits.

Three tuning techniques were implemented. The first technique involved the loading of one open end of each coupled into tunable capacitors. The second technique used a tunable resonator in series with the edge-coupled blocks. The final design made use of tunable feedback sections.

A detailed mathematical analysis of each design was performed. MATLAB code based on the analyses was written. The MATLAB simulations were compared to Agilent Advanced Design System …


Teaching Creativity In Technical Communication Curricula, Curtis Robert Newbold Dec 2008

Teaching Creativity In Technical Communication Curricula, Curtis Robert Newbold

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis addresses the need to claim creativity as an essential component to our technical communication curricula as we prepare students for what their managers want. While many technical communication programs at universities across the country have recognized a need to teach skills beyond "writing technically," few, if any, have addressed or "claimed" a concept such as creativity that helps build these skills. I argue that creativity is what managers are looking for and what technical communication programs are already implementing. Claiming this concept will help us further define a discipline that is becoming much richer and help students develop …


Air Demand In Free Flowing Gated Conduits, David Peter Oveson Dec 2008

Air Demand In Free Flowing Gated Conduits, David Peter Oveson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A physical experimental setup of a circular, gated closed conduit was built at the Utah Water Research Laboratory (UWRL). Setup configurations were modified and data were measured to aid in the study of physical variables on air demand. It was determined that gate opening, gate and water surface roughness, and conduit length all were significant variables on the air demand measured through the conduit air vent. It was also determined that no noticeable air velocity profile existed above the air-water interface. A linear relationship was found between the air flow rate to water flow rate ratio (air-demand ratio) and head-to-gate …


Analysis Of Effectiveness Of Bridges With Partial Isolation, Wenying Hu Dec 2008

Analysis Of Effectiveness Of Bridges With Partial Isolation, Wenying Hu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A special class of seismically isolated bridges shares a common feature in that both ends of the superstructure are restrained and isolators over the columns of bridge uncouple the superstructure from the ground motions. They are defined as partial isolation bridges. From measured acceleration responses, effectiveness of full seismic isolation had been confirmed widely. However, the seismic isolation behavior in the partial isolation has not been widely observed.

The effectiveness of partial isolation is evaluated in this study. The static design procedures for linear and nonlinear partially isolated bridges are developed. Results from the static analysis of linear and nonlinear …


The Impact Of Religious Schema On Critical Thinking Skills, Matthew Kirby Dec 2008

The Impact Of Religious Schema On Critical Thinking Skills, Matthew Kirby

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to examine the relationship between critical thinking and religious schema as represented by religious orientation. Past research has included religious belief within the larger construct of paranormal belief, and demonstrated a correlation between high levels of paranormal belief and poor critical thinking skills. Studies in the psychology of religion suggested that a more complex religious measure based on religious orientation was necessary to understand these correlations. Additionally, schema theory offered a cognitive framework within which to experimentally test the cause of these correlations. This study found that primed religious schema did not account for …


Automated Data Type Identification And Localization Using Statistical Analysis Data Identification, Sarah Jean Moody Dec 2008

Automated Data Type Identification And Localization Using Statistical Analysis Data Identification, Sarah Jean Moody

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research presents a new and unique technique called SÁDI, statistical analysis data identification, for identifying the type of data on a digital device and its storage format based on data type, specifically the values of the bytes representing the data being examined. This research incorporates the automation required for specialized data identification tools to be useful and applicable in real-world applications. The SÁDI technique utilizes the byte values of the data stored on a digital storage device in such a way that the accuracy of the technique does not rely solely on the potentially misleading metadata information but rather …


Movement Patterns And Multi-Scale Factors That Influence Exotic Brook Trout And Endemic Bonneville Cutthroat Trout Distribution And Abundance In The Mill Creek Drainage, Utah, Benjamin Keith Nadolski Dec 2008

Movement Patterns And Multi-Scale Factors That Influence Exotic Brook Trout And Endemic Bonneville Cutthroat Trout Distribution And Abundance In The Mill Creek Drainage, Utah, Benjamin Keith Nadolski

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Introduced brook trout (Salvelinus fontinalis) are implicated as a primary factor leading to the decline in distribution and abundance of native cutthroat trout (Oncorhynchus clarkii). However, not all introductions are successful, suggesting local conditions influence the success of invasions. Therefore, I sought to determine the multi-scale factor(s) that influence brook trouts’ invasion success of native Bonneville cutthroat trout (Oncorhynchus clarkii utah) habitats in Mill Creek, Utah. I conducted patch occupancy surveys to determine watershed-scale brook trout and cutthroat trout distribution. I also determined the relative abundance of brook trout and cutthroat trout at the …


An Investigation Of The Effects Of Differential Reinforcement Of Alternative Behavior On Students With Mild/Moderate Disabilities In A School Classroom, Katrina Spangenberg Dec 2008

An Investigation Of The Effects Of Differential Reinforcement Of Alternative Behavior On Students With Mild/Moderate Disabilities In A School Classroom, Katrina Spangenberg

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study investigated the effects of differential reinforcement of alternative behavior (DRA), a behavior reduction procedure, on problem behavior exhibited by three elementary school students in a general education classroom. DRA involves reinforcement of an alternative behavior while withholding reinforcement for the inappropriate behavior. The three participants were classified as experiencing mild/moderate disabilities but received most services (and participated in this research) in a general education classroom. Problem behaviors included off-task, talk-outs, and inappropriate touching. Alternative behaviors included on-task and hand-raising to get teacher attention. Results indicated that DRA decreased off-task and talk-out behavior for two participants, although effects were …


Modeling, Designing, Fabricating, And Testing Of Channel Panel Flat Plate Heat Pipes, James R. Harris Dec 2008

Modeling, Designing, Fabricating, And Testing Of Channel Panel Flat Plate Heat Pipes, James R. Harris

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Flat plate heat pipes are very efficient passive two-phase heat transport devices. Their high efficiency and low mass are desirable in the aerospace and electronics industries. The highly competitive nature of the thermal management industry results in little awareness of the capabilities of at plate heat pipes, which has resulted in only a few applications of the technology. In the year 2000 a research and development project sponsored by Space Dynamics Laboratory was launched to investigate building carbon-based at heat pipes. The flat configuration is desireable to incorporate many components onto one thermal management system. Development led to the adoption …


Technologically Assisted Intervention (Tai): Are Clients Satisfied With Online Therapy?, Jennifer A. Morrow Dec 2008

Technologically Assisted Intervention (Tai): Are Clients Satisfied With Online Therapy?, Jennifer A. Morrow

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study examined the level of satisfaction reported by participants of a technologically assisted intervention study (TAI). TAI is a type of teletherapy done through online, live video conferencing. Satisfaction was examined at three different time points, post therapy, 3-months post therapy, and 6-months post therapy. Analyses examined if there were any changes in reported satisfaction over the three time periods. Participants received cognitive behavioral therapy (CBT) targeted at reducing symptoms of mild to moderately severe depression. A satisfaction measure was developed for this study, and included quantitative and qualitative items which were analyzed to determine participants' level of satisfaction. …


Academic Performance As A Predictor Of Student Growth In Achievement And Mental Motivation During An Engineering Design Challenge In Engineering And Technology Education, Nathan Mentzer Dec 2008

Academic Performance As A Predictor Of Student Growth In Achievement And Mental Motivation During An Engineering Design Challenge In Engineering And Technology Education, Nathan Mentzer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this correlational research study was to determine if students’ academic success was correlated with: (a) the student change in achievement during an engineering design challenge; and (b) student change in mental motivation toward solving problems and critical thinking during an engineering design challenge. Multiple experimental studies have shown engineering design challenges increase student achievement and attitude toward learning, but conflicting evidence surrounded the impact on higher and lower academically achieving students.

A high school classroom was chosen in which elements of engineering design were purposefully taught. Eleventh-grade student participants represented a diverse set of academic backgrounds (measured …


Measuring And Modeling Of Plant Root Uptake Of Organic Chemicals, Erik Dettenmaier Dec 2008

Measuring And Modeling Of Plant Root Uptake Of Organic Chemicals, Erik Dettenmaier

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Determining the root uptake of xenobiotic organic chemicals into plants is critical for assessing the human and ecological health risks associated with the consumption of plants growing in contaminated environments. Root uptake of xenobiotic organics occurs passively in conjunction with transpiration and the transport from root to shoot is ultimately controlled by passage through one or more lipid root membranes. The transpiration stream concentration factor (TSCF), the ratio between the concentration of a chemical in the xylem to that in the solution used by the roots, is used to describe the relative ability of an organic chemical to be passively …


Hydrogen Production Using Geothermal Energy, Theodore Wayne Hand Dec 2008

Hydrogen Production Using Geothermal Energy, Theodore Wayne Hand

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

With an ever-increasing need to find alternative fuels to curb the use of oil in the world, many sources have been identified as alternative fuels. One of these sources is hydrogen. Hydrogen can be produced through an electro-chemical process. The objective of this report is to model an electrochemical process and determine gains and or losses in efficiency of the process by increasing or decreasing the temperature of the feed water. In order to make the process environmentally conscience, electricity from a geothermal plant will be used to power the electrolyzer. Using the renewable energy makes the process of producing …


Intergranular Phases In Cyclically Annealed Yba2cu3o7-X And Their Implications For Critical Current Densities, Andrew Peter Clarke Dec 2008

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 YBa2Cu3O7-x during cyclic anneals between 780 and 980 ºC in oxygen at atmospheric pressure. Two endothermic reactions were detected: (a) the eutectic reaction of YBa2Cu3O7-x with CuO and BaCuO2 at 900 ºC (enthalpy ∆Ha) and (b) the peritectic reaction of YBa2Cu3O7-x with CuO at 950 ºC (∆Hb). During the first anneal, only reaction (b) is detected, and although it should only occur if there is an excess of CuO, …


Dechlorinating And Iron Reducing Bacteria Distribution In A Trichloroethene Contaminated Aquifer, Carmen Lourdes Yupanqui Zaa Dec 2008

Dechlorinating And Iron Reducing Bacteria Distribution In A Trichloroethene Contaminated Aquifer, Carmen Lourdes Yupanqui Zaa

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Operable Unit 5 (OU 5) area of Hill Air Force Base currently has two trichloroethene-contaminated groundwater plumes underneath residential areas in Sunset and Clinton, Utah. Bioremediation by biological reductive dechlorination can be an important mechanism for the removal of chlorinated compounds from the plumes. The presence of suitable bacteria to carry on reductive dechlorination is the key in the bioremediation process. The goal of this study was to determine the distribution and population density of the 16S rRNA genes of Bacteria, Dehalococcoides ethenogenes, Desulfuromonas michiganensis, Geobacter spp and Rhodoferax ferrireducens-like bacteria, as well as the functional genes trichloroethene reductive …


A Three-Dimensional, Time-Dependent Circulation Model Of Utah Lake, Eric V. Callister Dec 2008

A Three-Dimensional, Time-Dependent Circulation Model Of Utah Lake, Eric V. Callister

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Spatial and temporal variations of Utah Lake’s flow field were modeled using the Estuary Lake and Computer Model from the Centre for Water Research (CWR-ELCOM) at the University of Western Australia as part of an effort to increase understanding of the lake’s natural processes in order to restore the lake to its pristine, clear-water state and preserve the habitat of the June sucker, an endangered species. The model was validated using temperature measurements taken by sensors in 2007. The water temperature was a strong function of air temperature and incident short wave radiation, and was influenced to a lesser degree …


Two Highly Diverse Studies In Computing: A Vitruvian Framework For Distribution And A Search Approach To Cancer Therapies, Brian G. Smith Dec 2008

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 …


The Consciousness Of Damnation : A Hermeneutical Phenomenology Of The Fall Of The Self In Matthew Lewis's "The Monk"., Becky Lee Meadows Dec 2008

The Consciousness Of Damnation : A Hermeneutical Phenomenology Of The Fall Of The Self In Matthew Lewis's "The Monk"., Becky Lee Meadows

Electronic Theses and Dissertations

When Ambrosio in Matthew Lewis's 1796 gothic masterpiece, The Monk , signs a contract relegating his soul to Satan and eternal damnation, he has reached the culmination of 442 pages of mental anguish, of his self wrestling with his conscience to overcome what philosopher Paul Ricoeur terms the "servile will" (The Symbolism of Evil 151). In the novel, Ambrosio, a monk the reader discovers has become the pawn of Satan, hurls himself down a path to damnation in consciousness, a phenomenological path that leads to the damnation of his own self. The purpose of this dissertation is to explore this …


An Evolutionary Approach To Image Compression In The Discrete Cosine Transform Domain, Benjamin E. Banham Dec 2008

An Evolutionary Approach To Image Compression In The Discrete Cosine Transform Domain, Benjamin E. Banham

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This paper examines the application of genetic programming to image compression while working in the frequency domain. Several methods utilized by JPEG encoding are applied to the image before utilizing a genetic programming system. Specifically, the discrete cosine transform (DCT) is applied to the original image, followed by the zig-zag scanning of DCT coefficients. The genetic programming system is finally applied to the one-dimensional array resulting from the zig-zag scan. The research takes an existing genetic programming system developed for the spatial domain and develops DCT domain functionality. The results from the DCT domain-based genetic programming system are compared with …


Design, Analysis, And Development Of Cost Effective Canine Wheelchairs., Edward Bros Fowler Dec 2008

Design, Analysis, And Development Of Cost Effective Canine Wheelchairs., Edward Bros Fowler

Electronic Theses and Dissertations

Hind limb paralysis may occur in dogs for a variety of neurological or musculoskeletal reasons. For dogs with limited mobility their lack of ability to ambulate can have a great impact on their physical and mental health. Canine wheelchairs can provide these dogs with a mobility option. The purpose of this project was to design a cost effective, adjustable, and lightweight canine wheelchair for dogs with hind limb paralysis. To account for the diverse range of canine breed sizes, wheelchairs were categorized into three separate designs (small, medium, and large size wheelchairs). A quality function deployment (QFD) matrix was created …


Measurement Of Fine Spatial Scale Ecohydrologic Gradients In A Pinyon-Juniper Ecosystem, Matthew David Madsen Dec 2008

Measurement Of Fine Spatial Scale Ecohydrologic Gradients In A Pinyon-Juniper Ecosystem, Matthew David Madsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

With the dramatic expansion of pinyon-juniper woodlands over the last century, improved understanding of how these woodlands modify infiltration properties is needed, in order for land managers to make informed decisions on how to best manage their specific resources. However, current methods for measuring soil infiltration are often limited by low sample sizes and high experimental error, due to constraints associated with remote, non agricultural settings. This thesis first presents a scheme for automating and calibrating two commercially available infiltrometers, which allows collection of a large number of precise unsaturated infiltration measurements in a relatively short period of time. Secondly, …


Ethylene Synthesis And Sensitivity In Crop Plants, Joseph F. Romagnano Dec 2008

Ethylene Synthesis And Sensitivity In Crop Plants, Joseph F. Romagnano

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The gaseous plant hormone ethylene is a small molecule that regulates developmental change. Research was conducted in three areas: sensitivity, synthesis, and alterations to synthesis. Vegetative pea plants were more sensitive than radish plants to atmospheric ethylene. Light intensity did not affect ethylene sensitivity. Ethylene synthesis rates were measured for unstressed cotton, corn, soybean, and tomato plants. The per-plant ethylene synthesis rate ranged from 0.1-80 pmol plant-1 s-1. However, when normalized to net photosynthetic rate, this range was 1-4 µmol of ethylene synthesis per mol of CO2 uptake. Diurnal cycles in ethylene synthesis were present in …


Comparing Dynamic Risk-Based Scheduling Methods With Mrp Via Simulation., Li Sun Dec 2008

Comparing Dynamic Risk-Based Scheduling Methods With Mrp Via Simulation., Li Sun

Electronic Theses and Dissertations

Material Requirements Planning (MRP) is one of the earliest production scheduling approaches that utilizes computers. MRP is still regarded as one of the most widely used systems for production scheduling. Even though MRP has made contributions, there are some fundamental problems (i.e. the assumption of infinite capacity and fixed lead times) which make the MRP system vulnerable to effects of uncertainty. To overcome this fundamental flaw, there was a trend towards the development of detailed finite-capacity scheduling systems (i.e. MRP II, ERP, and APO). All these MRP-based systems still ignore variability and randomness and are inherently push systems. Instead of …