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Physical Sciences and Mathematics

Theses/Dissertations

2008

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Molecular Hydrogen Adsorbed On Mgo (100) Surfaces: A Thermodynamic Study, Lillian Ruth Frazier Dec 2008

Molecular Hydrogen Adsorbed On Mgo (100) Surfaces: A Thermodynamic Study, Lillian Ruth Frazier

Doctoral Dissertations

The thermodynamics of molecular hydrogen adsorbed on MgO (100) surfaces has been examined using high resolution volumetric adsorption isotherm techniques. These studies were undertaken using highly perfect, narrow size distributed MgO nanocubes with essentially single (100) facet exposure and extremely high chemical purity. A narrowly spaced (in temperature) series of isotherms were performed between the temperatures of ~7K and the triple point (13.8 K) using H2 and D2 gas.

A minimum of five, and in some cases seven, discrete adsorption steps are clearly observed in each isotherm trace. Analysis of these data indicate that the monolayer film forms …


Sb-Corla: Schema-Based Constructivist Robot Learning Architecture, Yifan Tang Dec 2008

Sb-Corla: Schema-Based Constructivist Robot Learning Architecture, Yifan Tang

Doctoral Dissertations

This dissertation explores schema-based robot learning. I developed SB-CoRLA (Schema- Based, Constructivist Robot Learning Architecture) to address the issue of constructivist robot learning in a schema-based robot system. The SB-CoRLA architecture extends the previously developed ASyMTRe (Automated Synthesis of Multi-team member Task solutions through software Reconfiguration) architecture to enable constructivist learning for multi-robot team tasks. The schema-based ASyMTRe architecture has successfully solved the problem of automatically synthesizing task solutions based on robot capabilities. However, it does not include a learning ability. Nothing is learned from past experience; therefore, each time a new task needs to be assigned to a new …


Collective Behavior Of Interacting Magnetic Nanoparticles, Noppi Widjaja Dec 2008

Collective Behavior Of Interacting Magnetic Nanoparticles, Noppi Widjaja

Doctoral Dissertations

In the past, Low Dimensional Materials by Design group at ORNL in collaboration with students from the University of Tennessee, have successfully tailored and studied magnetic nanostructures in 2D, 1D and 0D spatial confinement on Cu(111) substrates. They observed a striking collective ferromagnetic long-range order in Fe-nanodots on Cu(111) surface which can be stabilized through the indirect exchange interaction mediated by the substrate. This type of magnetic interaction was expected to have little effect on promoting a global ferromagnetic order in a randomly distributed dot assembly. It is for certain that we need a better understanding of the relative roles …


Emergent Phenomena In Spatially Confined Manganites, Thomas Z. Ward Dec 2008

Emergent Phenomena In Spatially Confined Manganites, Thomas Z. Ward

Doctoral Dissertations

Rare earth manganites exhibit colossal magnetoresistance (CMR). There is evidence that alloyed single crystal materials in this class can display electronic inhomogeneity in which areas with vastly different electronic and magnetic properties can form and coexist in phase separated domains ranging in size from a few nanometers to micrometers. This phase separation (PS) is of particular interest, as it has been suggested that it is the central feature that leads to CMR in manganites, the Mott transition in VO2 and may play a role in high-TC superconductivity in cuprates. However there is debate as to its precise role.

The …


Scalable Graph Algorithms With Applications In Genetics, Yun Zhang Dec 2008

Scalable Graph Algorithms With Applications In Genetics, Yun Zhang

Doctoral Dissertations

Graph theoretical approaches have been widely used to solve problems arising in bioinformatics and genomic analysis. In particular, enumeration problems such as maximal clique and maximal biclique finding are cores for addressing many biological problems, such as the integration of genome mapping data. However, the enumeration problems may become computation and memory bot- tlenecks for genome-scale elucidation of biological networks due to their NP-hard nature and the huge memory requirements.

Therefore, this research is interested in developing exact, scalable, and efficient algorithms for these biological problems. The Clique Enumerator including a maximal clique enumeration algo- rithm and its parallel …


A Socioeconomic Study Of The Non-Industrial Private Forest Landowner Wood Supply Chain Link In The Cumberland Plateau Region Of Tennessee, Kevin Patrick Hoyt Dec 2008

A Socioeconomic Study Of The Non-Industrial Private Forest Landowner Wood Supply Chain Link In The Cumberland Plateau Region Of Tennessee, Kevin Patrick Hoyt

Doctoral Dissertations

The Cumberland Plateau in Tennessee currently is experiencing widespread forest parcelization and changes in species composition as a result of changes in land use and ownership. These changes can be attributed partially to industrial forest land divestiture, the lingering effects of the 1998 – 2002 Southern Pine Beetle (SPB) epidemic, and expanding development due to increasing population growth. The region has recently become a focus of debate concerning land use change, land management practices, and the effects on biodiversity.

A stratified random sample of 1600 Nonindustrial Private Forest (NIPF) landowners owning 40 or more acres of forestland were surveyed obtaining …


Forestry Extension In Tennessee: Comparing Traditional And Web-Based Program Delivery Methods, Samuel Wayne Jackson Dec 2008

Forestry Extension In Tennessee: Comparing Traditional And Web-Based Program Delivery Methods, Samuel Wayne Jackson

Doctoral Dissertations

As the traditional forestry Extension clientele in Tennessee changes, Extension professionals need to adapt and deliver programs in such a way as to reach the maximum audience while ensuring the educational benefit of the program and remaining within budget. The development of the Internet and associated web-based programs presents a new tool by which Extension professionals can develop and deliver educational programs to clientele.

This study compared two Extension program delivery methods, web-based and traditional field-based. A series of field workshops were held and participants were surveyed. From these field workshops, a web-based program was developed and was marketed to …


Assessing The Tree-Ring Oxygen Isotope Hurricane Proxy Along The Atlantic And Gulf Coastal Seaboards, Usa, Whitney L. Nelson Dec 2008

Assessing The Tree-Ring Oxygen Isotope Hurricane Proxy Along The Atlantic And Gulf Coastal Seaboards, Usa, Whitney L. Nelson

Doctoral Dissertations

A recent increase in hurricane activity has put coastal populations at risk. To better understand hurricane activity, it is necessary to look beyond the modern instrumental record, using proxy records to establish modes of past variability. The utility of a newly developed tree-ring oxygen isotope proxy is further assessed. I present oxygen isotope time series from three sites: Francis Marion and Sandy Island, South Carolina and Eglin Air Force Base, Florida. Proxy results are verified against the instrumental record of hurricane occurrence. The sites record similar percentages (45% for Francis Marion and Sandy Island, 63% for Eglin Air Force Base) …


New Carbon-Carbon Bond Forming Reactions Mediated By Boron And Transition Metal Halides, Travis R. Quick Dec 2008

New Carbon-Carbon Bond Forming Reactions Mediated By Boron And Transition Metal Halides, Travis R. Quick

Doctoral Dissertations

This dissertation summarizes the recent use of boron and transition metal halides to form new carbon-carbon bonds. Several novel reactions have been discovered. These include the haloallylation of aryl aldehydes with boron trihalide; alkyne-aldehyde couplings mediated by boron trihalide to give either (Z,Z)-1,5-dihaloalkenes or (Z,E)-1,5- dihaloalkenes; dehydroxylation of benzylic alcohols and in situ generated benzylic alcohol salts with iron(III) chloride and triethylsilane to afford diarylmethanes; and, the alkenylation of allylic, benzylic, and propargylic alcohols with phenylacetylenes and titanium(IV) halide. The results of these studies strongly imply a cationic mechanism. The reaction methodology of the research described herein can be characterized …


Synthesis Of A Dirhodium Tetraphosphine Catalyst And The Effect Of Various H2/Co Ratios On The Catalyst, Christina Joanne Sweeney Dec 2008

Synthesis Of A Dirhodium Tetraphosphine Catalyst And The Effect Of Various H2/Co Ratios On The Catalyst, Christina Joanne Sweeney

Honors Theses

No abstract provided.


Increasing The Recycling Rate In Clark County, Nevada, Emerald Laija Dec 2008

Increasing The Recycling Rate In Clark County, Nevada, Emerald Laija

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study was to identify and evaluate policies that could increase the amount of municipal solid waste recycled in Clark County, Nevada. Clark County has not met the Nevada State goal of a 25% recycling rate since it was established by the Nevada Legislature in 1991. Using the system dynamics problem solving approach, a model for Clark County was adapted from a model developed by Stave (2008) to test policy options. There was no feedback in the model due to the long lifespan of the landfill servicing Clark County and the relatively shorter time horizon of the …


The Environmental And Economic Benefits Of Highway Access Management: A Multivariate Analysis Using System Dynamics, Dan Andersen Dec 2008

The Environmental And Economic Benefits Of Highway Access Management: A Multivariate Analysis Using System Dynamics, Dan Andersen

UNLV Theses, Dissertations, Professional Papers, and Capstones

Better management of highway operations can be achieved, in part, by controlling vehicular access to adjacent properties and cross streets. This tactic, referred to as access management, has proven safety and operational benefits. However, doubts remain regarding its environmental and economic benefits.

I hypothesize that one environmental indicator, carbon emissions, will decrease with proper access management. Controlling access increases the speed at which vehicles travel, improving fuel efficiency and reducing carbon emissions. My hypothesis relative to financial impacts is that access management will neither help nor harm businesses. Controlling access can reduce travel time which has the effect of increasing …


Tolerance Intervals In Random-Effects Models, Kakotan Sanogo Dec 2008

Tolerance Intervals In Random-Effects Models, Kakotan Sanogo

Theses and Dissertations

In the pharmaceutical setting, it is often necessary to establish the shelf life of a drug product and sometimes suitable to assess the risk of product failure at the desired expiry period. The current statistical methodology use confidence intervals for the predicted mean to establish the expiry period and prediction intervals for a predicted new assay value or a tolerance interval for a proportion of the population for use in a risk assessment. A major concern is that most methodology treat a homogeneous subpopulation, say batch, either as a fixed effect and therefore uses a fixed-effects regression model (Graybill, 1976) …


Synthesis, Characterization, And Application Of Ag Nanostructures, Stephen Hudson Dec 2008

Synthesis, Characterization, And Application Of Ag Nanostructures, Stephen Hudson

All Dissertations

Noble metal nanoparticles (NPs) have been used for many centuries; however their properties were not truly scrutinized until Michael Farady's investigations in the 1850's. Advances in the field of nanotechnology over the last three decades have enabled insights into the properties of materials as their dimensions are reduced to the nanoscale. The repercussions of these insights are seen in many modern applications.
In this dissertation, properties of novel nanostructures based on Ag NPs are presented and discussed. The exceptional optical properties of Ag NPs stem from the collective oscillations of the conduction electrons known as plasmon resonances. The excitation of …


Fabrication And Optical Properties Of Noble Metal Nanostructures, Mark Kinnan Dec 2008

Fabrication And Optical Properties Of Noble Metal Nanostructures, Mark Kinnan

All Dissertations

Experimental and theoretical results are presented in Chapters 2, 3, and 4 on the effects of dielectric medium, particle size, and interparticle distance, respectively, on plasmon coupling in two-dimensional arrays of silver nanoparticles. The arrays were fabricated via the self-assembly of single crystal particles from c.a. 46 nm to 287 nm on PVP-modified glass substrates. Spin-coated poly(methylmethacrylate) layers were used to immobilize the particles and prevent their surface aggregation. Varying the thickness of the PMMA layer made it possible to change the average dielectric medium between the particles. UV-Visible spectra of different arrays were compared to the corresponding electron microscope …


Fluorescent Conjugated Polymer Dots For Single Molecule Imaging And Sensing Applications, Changfeng Wu Dec 2008

Fluorescent Conjugated Polymer Dots For Single Molecule Imaging And Sensing Applications, Changfeng Wu

All Dissertations

While single molecule imaging and sensing hold the promise of providing unprecedented detail about cellular processes, many advanced applications are limited by the lack of appropriate fluorescence probes. In many cases, currently available fluorescent labels are not sufficiently bright and photostable to overcome the background associated with various autofluorescence and scattering processes. This dissertation describes research efforts focused on the development of a novel class of fluorescent nanoparticles called conjugated polymers dots (CPdots) for single molecule fluorescence detection. The CPdots contain highly fluorescent π-conjugated polymers that have been refined over the last decades as the active material in polymer light-emitting …


Two Categories Of Refutation Decision Procedures For Classical And Intuitionistic Propositional Logic, Edward Doyle Dec 2008

Two Categories Of Refutation Decision Procedures For Classical And Intuitionistic Propositional Logic, Edward Doyle

All Dissertations

An automatic theorem prover is a computer program that proves theorems without the assistance of a human being. Theorem proving is an important basic tool in proving theorems in mathematics, establishing the correctness of computer programs, proving the correctness of communication protocols, and verifying integrated circuit designs.
This dissertation introduces two new categories of theorem provers, one for classical propositional logic and another for intuitionistic propositional logic. For each logic a container property and generalized algorithm are introduced.
Many methods have been developed over the years to prove theorems in propositional logic. This dissertation describes and presents example proofs for …


Characterization Of Campus Parking Lot Stormwater And Remediation Of Risks Using Constructed Wetland Treatment Systems, Andrew Mcqueen Dec 2008

Characterization Of Campus Parking Lot Stormwater And Remediation Of Risks Using Constructed Wetland Treatment Systems, Andrew Mcqueen

All Theses

Campus parking lot stormwater (CPLSW) runoff mobilizes a variety of constituents from vehicular and atmospheric deposition that may pose risks to receiving aquatic systems. The overall objective of this research was to provide an approach for risk characterization, toxicity identification, and remediation of constituents of concern in CPLSW. The specific objectives of this research were to: (1) Characterize campus parking lot stormwater (CPLSW) to discern the constituents of concern present in these waters; (2) Perform TIE manipulations to identify possible fractions of concern in CPLSW, and; (3) Evaluate the performance of a pilot-scale constructed wetland treatment system (CWTS) designed to …


Insights Into Biogeophysical Signatures Using Polarization Force Microscopy, Elizabeth Bartosik Dec 2008

Insights Into Biogeophysical Signatures Using Polarization Force Microscopy, Elizabeth Bartosik

All Theses

The success of bioremediation strategies is dependent upon effective monitoring of microorganisms in the subsurface. Induced polarization (IP) may represent a cost-effective, complementary technique to existing borehole-based microbe detection schemes. Recent studies show a significant, yet poorly understood IP effect associated with the presence of bacteria in aqueous and porous media. This effect is believed to be rooted in the physicochemical surface interactions between cells and minerals which we probe using polarization force microscopy. Polarization force experiments were conducted on a hydrated mica surface using the gram positive bacterium Bacillus subtilis and the gram negative bacterium Escherichia coli. On all …


Application Of Resiliency Theory And Adaptive Cycles As A Framework For Evaluating Change In Amenity-Transition Communities, Scott L. Hoffmann Dec 2008

Application Of Resiliency Theory And Adaptive Cycles As A Framework For Evaluating Change In Amenity-Transition Communities, Scott L. Hoffmann

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In recent decades, many rural, natural resource-dependent communities have experienced ubiquitous and oftentimes substantial economic decline due to downturns in their commodity-oriented industries. In spite of this, communities with access to varying forms of natural capital have experienced an upsurge in activities such as recreation, tourism, second home growth, and retirement in-migration. If managed properly, amenity-oriented development has potential to reverse economic decline by attracting tourists, entrepreneurs, younger and more educated workers, and retirees, and may ultimately generate economic diversification, local growth, and an improved quality of life for residents. While there are literally thousands of potential measures of well-being, …


The Process Of Tracking In Mathematics In Box Elder School District, Megan Haramoto Bushnell Dec 2008

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 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, …


Approximations To Continuous Processes In Hierarchical Models, Amanda Cangelosi Dec 2008

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 Dec 2008

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 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 …


Sedimentology, Stratigraphy, And Organic Geochemistry Of The Red Pine Shale, Uinta Mountains, Utah: A Prograding Deltaic System In A Mid-Neoproterozoic Interior Seaway, Caroline Amelia Myer Dec 2008

Sedimentology, Stratigraphy, And Organic Geochemistry Of The Red Pine Shale, Uinta Mountains, Utah: A Prograding Deltaic System In A Mid-Neoproterozoic Interior Seaway, Caroline Amelia Myer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Red Pine Shale (RPS; ~1120m thick), uppermost formation of the Neoproterozoic Uinta Mountain Group, Utah, is an organic-rich sedimentary succession interpreted as a marine deltaic system that delivered immature sediment from the north that mixed with mature sediment from the east. Multiple data sets suggest regional climate and sea-level changes associated with changing organic-carbon burial rates.

Six facies were identified and represent wave-, tidal-, and river-influenced parts of the distal prodelta to delta front in a marine system. These include the shale facies and associated concretion facies (distal prodelta), the shale-sandstone facies (proximal prodelta to delta front), the slump …


Perceived Crowding And Visitor Support For Use Rationing: A Reanalysis Of Existing Data, Jascha M. Zeitlin Dec 2008

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 …


Hydrological Characterization Of A Riparian Vegetation Zone Using High Resolution Multi-Spectral Airborne Imagery, Osama Zaki Akasheh Dec 2008

Hydrological Characterization Of A Riparian Vegetation Zone Using High Resolution Multi-Spectral Airborne Imagery, Osama Zaki Akasheh

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Middle Rio Grande River (MRGR) is the main source of fresh water for the state of New Mexico. Located in an arid area with scarce local water resources, this has led to extensive diversions of river water to supply the high demand from municipalities and irrigated agricultural activities. The extensive water diversions over the last few decades have affected the composition of the native riparian vegetation by decreasing the area of cottonwood and coyote willow and increasing the spread of invasive species such as Tamarisk and Russian Olives, harmful to the river system, due to their high transpiration rates, …


Understanding Unfolding Change And The Value Of Strategic Unification In Recent Usu Information Technology Functional Realignment, Eric S. Hawley Dec 2008

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.


Threat Perception As A Determinant Of Pro-Environmental Behaviors: Public Involvement In Air Pollution Abatement In Cache Valley, Utah, Joshua D. Marquit Dec 2008

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 …