Physical Sciences and Mathematics Commons^™

Transformation Of Swine Manure And Algal Consortia To Value-Added Products, Mahmoud A. Sharara

Graduate Theses and Dissertations

The swine production sector is projected to grow globally. In the past, this growth manifested itself in increased herd sizes and geographically concentrated production. Although economically sound, these trends had negative consequences on surrounding ecosystems. Over-application of manure resulted in water quality degradation, while long-term storage of manure slurries was found to promote release of potent GHG emissions. There is a need for innovative approaches for swine manure management that are compatible with current scales of production, and increasingly strict environmental regulations.

This study aims to investigate the potential for incorporating gasification as part of a novel swine manure management …

Physical Records Of Impacts In The Early And Modern Solar System, Robert Ellis Beauford

Graduate Theses and Dissertations

The study of terrestrial meteorite impact craters and of impacted meteorites expands our understanding of cratered rocky surfaces throughout the solar system. Terrestrial craters uniquely expand upon data from remote imaging and planetary surface exploration by providing analogs for understanding the buried sub-surface portions of impact structures, while impacted meteorites provide examples of a much wider range of surface and subsurface impactite materials than we can directly sample thus far through solar system exploration.

This report examines three facets of the impact record preserved in terrestrial impact craters and in meteorites. First, it looks at the macroscopic structure of the …

The Power Behind The Controversy: Understanding Local Policy Elites' Perceptions On The Benefits And Risks Associated With High Voltage Power Line Installation In The State Of Arkansas, Rachael Marie Moyer

Graduate Theses and Dissertations

Following a proposal for the installation of high voltage power lines in northwest Arkansas, a controversial policy debate emerged. Proponents of the transmission line argue that such an installation is inevitable and necessary to efficiently and reliably support the identified electric load in the region. Opponents claim that the lines will degrade the natural environment and hamper the tourism-based local economy in affected regions, notably in Ozark Mountain areas. This study seeks to understand how local policy elites perceive the benefits and risks associated with proposed transmission lines, which is a critical step in comprehending the formation and changes of …

Stratigraphic Characterization And Depositional History Of The Barnett Shale Within The Fort Worth Basin In Denton County, Texas, Matthew Loren Cope

Graduate Theses and Dissertations

The Barnett shale, located in the Fort Worth Basin, is a geologic unit that has undergone extensive study and currently holds great economic importance. It contains well-known stratigraphy, but still holds questions with regard to the specific stratigraphic variation over much of its area. Denton County contains a large geographic area of the Barnett shale, and holds many answers to the varying stratigraphy of the Barnett shale, as well as an explanation into its depositional history. The investigation involved the use of two cross sections utilizing 32 and 26 wells respectively in the western region of Denton County, Texas. From …

Epitaxial Growth Of Silicon On Poly-Crystalline Si Seed Layer At Low Temperature By Using Hot Wire Chemical Vapor Deposition, Manal Abdullah Aldawsari

Graduate Theses and Dissertations

There has been a growing interest in using low cost material as a substrate for the large grained polycrystalline silicon photovoltaic devices. The main property of those devices is the potential of obtaining high efficiency similar to crystalline Si devices efficiency yet at much lower cost because of the thin film techniques. Epitaxial growth of Si at low temperatures on low cost large grained seed layers, prepared by aluminum induced crystallization method (AIC), using hot wire chemical vapor deposition (HWCVD) system is investigated in this thesis. In this work, different parameters have been studied in order to optimize the growth …

Mirror Buckling Transitions In Freestanding Graphene Membranes Induced Through Scanning Tunneling Microscopy, James Kevin Schoelz

Graduate Theses and Dissertations

Graphene has the ability to provide for a technological revolution. First isolated and characterized in 2004, this material shows promise in the field of flexible electronics. The electronic properties of graphene can be tuned by controlling the shape of the membrane. Of particular interest in this endeavor are the thermal ripples in graphene membranes. Years of theoretical work by such luminaries as Lev Landau, Rudolf Peierls, David Mermin and Herbert Wagner have established that 2D crystals should not be thermodynamically stable. Experimental research on thin films has supported this finding. Yet graphene exists, and freestanding graphene films have been grown …

Geologic Controls On Oil And Gas Accumulation And Production From Missourian Stage Granite Wash Reservoirs In The Western Anadarko Basin, Wheeler County, Texas, Derrell Mathis

Graduate Theses and Dissertations

Up-to-date regional and local Granite Wash data of any form is either too scarce to reference or highly privatized by exploration and production companies operating in the region. The objective of this research is to correlate horizontal production data with mapped depositional trends from Upper Pennsylvanian (Missourian Stage) Granite Wash reservoirs in the Western Anadarko Basin in northeastern Wheeler County, Texas. The correlation of raster logs to define various trap type and geometries in Missourian Granite Wash reservoirs of Wheeler County, Texas is used to understand the geologic controls on oil and gas accumulation and production. The analysis includes detailed …

Simulation In Algorithmic Self-Assembly, Jacob Hendricks

Graduate Theses and Dissertations

Winfree introduced a model of self-assembling systems called the abstract Tile Assembly Model (aTAM) where square tiles with glues on their edges attach spontaneously via matching glues to form complex structures. A generalization of the aTAM called the 2HAM (two-handed aTAM) not only allows for single tiles to bind, but also for "supertile" assemblies consisting of any number of tiles to attach. We consider a variety of models based on either the aTAM or the 2HAM. The underlying commonality of the work presented here is simulation. We introduce the polyTAM, where a tile system consists of a collection of polyomino …

Enabling Runtime Self-Coordination Of Reconfigurable Embedded Smart Cameras In Distributed Networks, Franck Ulrich Yonga Yonga

Graduate Theses and Dissertations

Smart camera networks are real-time distributed embedded systems able to perform computer vision using multiple cameras. This new approach is a confluence of four major disciplines (computer vision, image sensors, embedded computing and sensor networks) and has been subject of intensive work in the past decades. The recent advances in computer vision and network communication, and the rapid growing in the field of high-performance computing, especially using reconfigurable devices, have enabled the design of more robust smart camera systems. Despite these advancements, the effectiveness of current networked vision systems (compared to their operating costs) is still disappointing; the main reason …

Characterization Of Cellulase Enzyme Inhibitors Formed During The Chemical Pretreatments Of Rice Straw, Kalavathy Rajan

Graduate Theses and Dissertations

Production of fuels and chemicals from a renewable and inexpensive resource such as lignocellulosic biomass is a lucrative and sustainable option for the advanced biofuel and bio-based chemical platform. Agricultural residues constitute the bulk of potential feedstock available for cellulosic fuel production. On a global scale, rice straw is the largest source of agricultural residues and is therefore an ideal crop model for biomass deconstruction studies. Lignocellulosic biofuel production involves the processes of biomass conditioning, enzymatic saccharification, microbial fermentation and ethanol distillation, and one of the major factors affecting its techno-economic feasibility is the biomass recalcitrance to enzymatic saccharification. Preconditioning …

Terrestrial Impacts Of The Central Atlantic Magmatic Province On Western Pangea, Todd Kenneth Knobbe

Graduate Theses and Dissertations

Earth's climate is predominantly controlled by the fluctuation of greenhouse gases, specifically CO2 and CH4, over geologic time. The late Triassic is a period of abrupt climate change that has been associated with a disruption to the global carbon cycle due the emplacement of the Central Atlantic Magmatic Province (CAMP). Evidence has shown that this global carbon cycle perturbation may be the culprit for the end-Triassic extinction. The Whitmore Point Member of the Moenave Formation is a lacustrine deposit with a disputed age of either late Triassic or early Jurassic and currently no absolute dating techniques can be applied to …

Distinguishing Macrophage Activation States By Mass Spectrometry, Matthias Manfred Knust

Graduate Theses and Dissertations

Macrophages are versatile and highly adaptive cells that are involved in a wide range of physiological processes including host defense, homeostasis or regeneration, as well as pathogenesis. They react to their microenvironment, assuming various roles based on chemical and/or physical cues, and can reversibly shift between these so-called activation states. Concurrently, the technique of immunohistochemistry is used to gain spatial information on activated macrophages on tissue sections. The aim of this work was to find mass spectral biomarkers that allow the differentiation of activation states, and establish conditions that can be used in imaging mass spectrometry (IMS) experiments to investigate …

Design And Verification Environment For High-Performance Video-Based Embedded Systems, Michael Mefenza Nentedem

Graduate Theses and Dissertations

In this dissertation, a method and a tool to enable design and verification of computation demanding embedded vision-based systems is presented. Starting with an executable specification in OpenCV, we provide subsequent refinements and verification down to a system-on-chip prototype into an FPGA-Based smart camera. At each level of abstraction, properties of image processing applications are used along with structure composition to provide a generic architecture that can be automatically verified and mapped to the lower abstraction level. The result is a framework that encapsulates the computer vision library OpenCV at the highest level, integrates Accelera's System-C/TLM with UVM and QEMU-OS …

Source Constraints Of Ore Metals In Mississippi Valley-Type Deposits In Central And Eastern Tennessee Using Pb Isotopes, Austin Moyers

Graduate Theses and Dissertations

The Mississippi Valley-Type (MVT) Central and East Tennessee (TN) Districts contain economically significant lead-zinc deposits that occur in the Early Ordovician carbonates of the Knox Group. Although both districts share similar host rock, have similar temperatures of formation, and typically fill open spaces of collapse breccias or replace their host carbonates, previous studies may suggest that these ores did not form from the same mineralizing fluids and may have different Pb sources. Nu Plasma MC-ICP-MS Pb isotopic analyses on sulfides from Central and East TN were conducted and the metal sources evaluated. Results were plotted on covariation diagrams with respect …

Controls On Dissolution Rate Variation At A Pair Of Underflow-Overflow Springs At The Savoy Experimental Watershed, Kiefer Allen Vaughn

Graduate Theses and Dissertations

Physical dissolution experiments and numerical modeling have been used in the past to study limestone dissolution rates. Numerical models have typically used constant dissolution rates, whereas rates in nature vary in time. Limestone tablets allow natural estimation of rates over month time scales, but these rates cannot necessarily be extrapolated to geologic timescales and also do not aid our understanding of short term variability. This study characterizes natural variability in these rates and examines potential causes of that variability from first principles. This may enable more accurate projections of dissolution rates within models. This study combines measurement of physical and …

Subsurface Fluid Flow Through The Mississippian Section Of North-Central Oklahoma, Carolyn Brown

Graduate Theses and Dissertations

This study consisted of using drill stem tests, seismic amplitude data, and well logs to create the parameters needed to construct a groundwater flow model for a portion of Osage County. At the start, a potentiometric map of Osage County, Oklahoma was generated to use as a basis for the initial hydraulic heads and the constant heads in the model. Next, three seismic amplitude images were produced in a seismic interpretation program, OpenDtect, to base the hydraulic conductivity values on. In addition, utilizing Gamma Ray on 12 separate wells east-west across the county, a structural cross-section was created within Petra. …

Experimental Verification And Integration Of A Next Generation Smart Power Management System, Tavis Clemmer

Graduate Theses and Dissertations

With the increase in energy demand by the residential community in this country and the diminishing fossil fuel resources being used for electric energy production there is a need for a system to efficiently manage power within a residence. The Smart Green Power Node (SGPN) is a next generation energy management system that automates on-site energy production, storage, consumption, and grid usage to yield the most savings for both the utility and the consumer. Such a system automatically manages on-site distributed generation sources such as a PhotoVoltaic (PV) input and battery storage to curtail grid energy usage when the price …

Logarithmic Spiral Arm Pitch Angle Of Spiral Galaxies: Measurement And Relationship To Galactic Structure And Nuclear Supermassive Black Hole Mass, Benjamin Lee Davis

Graduate Theses and Dissertations

In this dissertation, I explore the geometric structure of spiral galaxies and how the visible structure can provide information about the central mass of a galaxy, the density of its galactic disk, and the hidden mass of the supermassive black hole in its nucleus. In order to quantitatively measure the logarithmic spiral pitch angle (a measurement of tightness of the winding) of galactic spiral arms, I led an effort in our research group (the Arkansas Galaxy Evolution Survey) to modify existing two-dimensional fast Fourier transform software to increase its efficacy and accuracy. Using this software, I was able to lead …

Incorporating Environmental And Social Factors Into Decision-Making Of An Oil And Gas Industry To Improve Sustainability, Gaurav Dabhadkar

Graduate Theses and Dissertations

The energy industry (including the oil and gas industry) is facing unparalleled scrutiny and demands from stakeholders including investors, regulators (industry and environmental), communities, and other stakeholders. Sustainable development is one of the major concerns of the oil and gas industry. Companies are seeking to increase sustainability of their operations by considering environmental and Social concerns in addition to economic concerns. Oil and gas companies need to take decisions at different stages of the product life cycle (e.g. planning, design, exploration, production, and clean-up) which have direct or indirect impact on the organization's objectives. Addressing economic, technical, Social, and environmental …

Pennsylvanian Subsurface Sequence Stratigraphy Based On 3d Seismic And Wireline Data In Western Osage County, Oklahoma, Alexander West

Graduate Theses and Dissertations

The Pennsylvanian System in the Mid-Continent United States has been studied for nearly a century. In north central Oklahoma, the Pennsylvanian is primarily composed of cyclothems. These cyclothems are sequences of alternating carbonate, clastic, and shale members. Because of this, these zones can be difficult to differentiate. This project provides valuable insight into better understanding the Pennsylvanian System in western Osage County, Oklahoma. The scope of this project is to perform a subsurface study to produce a detailed interpretation of the depositional history and stratigraphy of Pennsylvanian sequences in western Osage County.

This study features 3D seismic and well log …

Analysis Of Paleokarst Sinkholes In The Arkoma Basin Using 3-D Seismic, Michael Kumbalek

Graduate Theses and Dissertations

Paleokarst features are important to understand, both with regards to research geologists and to the petroleum industry. In terms of geology, understanding paleokarst features can yield more information about the depositional and surface environments of past times, and how diagenetic alteration affected the environment during the formation of karst features. In the petroleum industry, paleokarst features can have positive or negative consequence resulting in a potential reservoir with enhanced porosity due to the paleokarst features, or as a geo-hazard to prepare for or avoid when drilling.

Inspired by issues faced when drilling in the Ft. Worth basin, this study utilizes …

Interpretation At The Controller's Edge: The Role Of Graphical User Interfaces In Virtual Archaeology, Tyler Duane Johnson

Graduate Theses and Dissertations

The important role of graphical user interfaces (GUIs) as a medium of interaction with technology is well established in the world of media design, but has not received significant attention in the field of virtual archaeology. GUIs provide interactive capabilities and contextual information for 3D content such as structure-from-motion (SFM) models, and can represent the difference between "raw data" and thoughtful, skilled scholarly publications. This project explores the implications of a GUI created with the game engine Unity 3D (Unity) for a series of SFM models recorded at a structure known as the Area B House at the ancient central …

Analytical Comparison Of Contrasting Approaches To Estimating Competing Risks Models, Brian Stephen Rickard

Graduate Theses and Dissertations

Survival analysis is a commonly used tool in many fields but has seen little use in education research despite a common number of research questions for which it is well suited. Researchers often use logistic regression instead; however, this omits useful information. In research on retention and graduation for example, the timing of the event is an important piece of information omitted when using logistic regression. A simulation study was conducted to evaluate four methods of analyzing competing risks survival data, Cox proportional hazards regression, Weibull regression, Fine and Gray's Method, and Cox proportional hazards regression with frailty. College student …

Interpretation Of Late Cretaceous Volcanic Mounds And Surrounding Gulfian Series Formations Using 3d Seismic Data In Zavala County, Texas, Laura Claire Bennett

Graduate Theses and Dissertations

The Late Cretaceous Gulfian series is a prominent and important series across the State of Texas that has been extensively studied since the nineteenth century. It is composed of series of southeast-dipping shelf carbonates and clastics deposited on the northwest margin of the Gulf of Mexico Basin. In south Texas, the Gulfian series was deposited in the Rio Grande Embayment and Maverick Basin and is comprised of the Eagle Ford Group, Austin Group, Anacacho Limestone, San Miguel Formation, Olmos Formation, and Escondido Formation that crop out and continue basinward in the subsurface. Late Cretaceous volcanism formed volcanic mounds composed of …

Petrology And Weathering Environment Of Sub-Unconformity Limestone Unit: The Kessler Limestone Member Of The Bloyd Formation, Morrowan (Pennsylvanian) Northwest Arkansas, Thomas Daniels Dolan

Graduate Theses and Dissertations

In northwest Arkansas the thin, widespread Pennsylvanian Kessler Limestone of the Bloyd Formation is exposed in numerous locations. Comparison of various exposures shows the Kessler is heterogeneous in thickness and lithology. Thickening of the Kessler occurs southward into the Arkoma Basin where the interval has been commonly used as a horizon for natural gas exploration. The Kessler Limestone is underlain by the Dye Shale Member of the Bloyd Formation and overlain by the Trace Creek Shale of the Atoka Formation. The contact between the Kessler Limestone Member and the Trace Creek is a regional unconformity in the midcontinent, marked by …

An Investigation Of 3d Seismic Deep Basement Events In Osage County, Oklahoma, Kevin Matthew Liner

Graduate Theses and Dissertations

Deep basement events seen in 3D seismic surveys located in Osage County, Oklahoma can be observed and may have affect overlying sedimentary formations. The 3D surveys used in this study are on the Chautauqua platform about fifty miles northwest of Tulsa, Oklahoma. Stratigraphy of the work area spans base of the Permian to Precambrian formations, with basement depth averaging around 5000 ft in the area of the 3D seismic surveys. Cores spanning Precambrian to Pennsylvanian were examined in the area of the 3D seismic surveys. Hydrothermal minerals were observed in Mississippian age cores. The basement events where tracked using OpendTect …

Mapping Ancient Baldcypress Forests For Conservation At Black River, North Carolina, Jordan Nichole Burns

Graduate Theses and Dissertations

A few ancient baldcypress-bottomland hardwood forests survive across the southeastern United States in a mosaic of remnant old-growth stands left untouched by extensive logging during the early 20th century. Uncut stands in the Southeast that survived centuries of disturbance following European settlement tended to be too senescent and non-commercial to justify logging. Remnant ancient baldcypress forests at Black River, North Carolina, appear to contain the oldest living trees in eastern North America and The Nature Conservancy has protected several of these stands. However, the full extent of ancient bottomland forests along Black River is not known and many valuable tracts …

Toolstone Use In Ozark Prehistory: Assessing Adaptations To A Lithic Dichotomy In The Boston Mountains And Springfield Plateau, Luke Allen Morris

Graduate Theses and Dissertations

Toolstone use in the Ozark Mountains is a reactionary process reliant on how the landscape provides or constrains chipped stone for prehistoric populations. These technological adaptations are recognized at sites throughout the area, but no regional assessment of lithic assemblages provides answers as to why certain stones are used at a particular location. This thesis employs a five step mass analysis of lithic assemblages, and GIS visualizations to observe how the organization of stone technologies vary based on location within contrasting geologic contexts. The chert-bearing Springfield Plateau, and the Boston Mountains with siltstone, are two neighboring dichotomous landscapes that illustrate …

Inertial Force-Driven Synthesis Of Near-Infrared Plasmonic Nanosphere Composites: Physicochemical Characterizations, Joseph Noel Batta-Mpouma

Graduate Theses and Dissertations

Near-infrared (NIR) responsive nanoparticles (NPs) like gold nanorods (GNRs) are important in biomedical fields because of their transparency for biological tissues. Although GNRs are sought after as contrast agents for theranostics in cancer studies, capping ligands like cetyltrimethylammonium bromide (CTAB) for the GNR synthesis are toxic for biological tissues. The need for an alternative to toxic GNRs is of interest to alleviate the problem.

This work aimed to optimize the synthesis of NIR responsive nanosphere composites (NSCs) by inertial force (g-force) using colloidal gold NPs as model, elucidate the mechanism for the NSC formation, and study their detailed physicochemical characteristics. …

Disaggregating The Effect Of Drought And Heat Stress During Flowering On Spikelet Fertility In Rice, Lisa Straussberger

Graduate Theses and Dissertations

Due to rice’s wide geographic distribution, extending from 50°N to 35°S, rice is

forecasted to be the most vulnerable crop to warming global climates. Previous studies have

predicted lower rice yields and increasing rice yield variability due to higher frequencies of heat

stress events, and a higher variability in precipitation patterns due to global warming. As such,

understanding the effects of drought and heat stress intensity and frequency on rice yields is of

upmost importance to feeding the growing global population.

Given that drought and high-temperature stress often occur together, it is essential to

disaggregate the two individual stressors and …