Digital Commons Network^™

Field Observations And Computer Modeling Of Tornado-Terrain Interaction And Its Effects On Tornado Damage And Path, Nawfal Shihab Ahmed

Graduate Theses and Dissertations

Tornado forces on structures have been a research focus for the past decades, and some comparisons have been made to distinguish between straight boundary layer (SBL) wind and tornado wind forces on specific structures. However, very little attention has been paid to terrain effects on tornado damage and path. Available damage investigation data for four tornado locations (Joplin-2011, Tuscaloosa-2011, Parish-2011 and Mayflower-2014) is utilized to explore terrain effects on tornado damage and path. Google Earth, site visits and aerial images are employed to study the influence of terrain on an extent of damage and path variation. Additionally, a three dimensional …

Statistical Modeling Of The Temporal Dynamics In A Large Scale-Citation Network, Luis Javier Ek Jr.

Graduate Theses and Dissertations

Citation Networks of papers are vast networks that grow over time. The manner or the form a citation network grows is not entirely a random process, but a preferential attachment relationship; highly cited papers are more likely to be cited by newly published papers. The result is a network whose degree distribution follows a power law. This growth of citation network of papers will be modeled with a negative binomial regression coupled with logistic growth and/or Cauchy distribution curve. Then a Barabasi-Albert model, based on the negative binomial models, and a combination of the Dirichlet distribution and multinomial will be …

Spread Trading In Corn Futures Market, Ryan D. Napier

Graduate Theses and Dissertations

The non-linear relationship between old crop – new crop year spreads in corn futures market and stock-to-use (S-U) ratios published by the United States Department of Agriculture is analyzed. Using a non-linear logarithmic smooth transition regression (LSTR) model, we capture asymmetric market behaviors in high and low S-U regimes. Capturing this relationship and understanding the non-linear aspects of the relationship is of interest of grain merchandizers and speculators in the market. A spread trading strategy is simulated for the sample period, January 1985 through April 2015, to determine if the non-linear relationship is a profitable arbitrage opportunity in the market.

Dissemination And Persistence Of Plasmid Located, Integron Associated Antibiotic Resistant Genes In Wastewater Treatment Plant Effluent And Stream Water Bacteria, _ Suhartono

Graduate Theses and Dissertations

Transmissible plasmid-mediated integrons play important role in the persistence and dissemination of antibiotic resistance throughout the environment. Plasmids from 139 multi-antibiotic resistant Escherichia coli recovered from wastewater treatment plant effluent and upstream and downstream receiving stream water in Northwest Arkansas were extracted and profiled. Genes of class 1 and class 2 integrase (intI), mobilization (mob), sulfamethoxazole resistance (sul), and trimethoprim resistance (dfr) were detected using PCR and confirmed through DNA sequencing. Plasmids from almost half of the isolates (47%) were transmissible with mobF12 gene as the most frequently detected mobilization gene. Plasmid-borne class 1 with and without class 2 integrons …

Influences Of Channel Dredging On Avulsion Potential At The Atchafalaya River, Gordon William Mccain

Graduate Theses and Dissertations

In 1950, the U.S. Army Corps of Engineers (USACE) reported a rapid increase of water discharge from the Mississippi River to its distributary channel; the Atchafalaya River. If not prevented by man-made structures, the complete capture of the Mississippi River by the Atchafalaya River was predicted. The USACE report cites multiple causes for the observed increase in discharge partitioning, yet fails to assess the largescale channel dredging operations conducted throughout the Atchafalaya River Basin during the 1930's and 1940's as a potential cause for the increased discharge. To assess the role man-made interventions, specifically channel dredging, played in the increase …

Designing Sewn Circuits And Stem Self-Efficacy In Middle School Girls, Kara Kaiser

Graduate Theses and Dissertations

The purpose of this study is to determine if the experience of designing and sewing LilyPad Arduino circuits in crafts projects can increase middle school girls’ STEM self-efficacy. Boys STEM self-efficacy will also be assessed to determine if LilyPad Arduino circuits can also increase boys’ STEM self-efficacy. Researchers have been wondering why there is a male dominance in STEM (science, technology, engineering and mathematics) fields and why some women do not have a particular interest in these subjects. There are several reasons this could happen; stereotypes conveyed to them by parents and/or teachers, they genuinely are not interested in STEM …

A Method Comparison And Stressor-Response Experimental Study Of Nitrogen And Phosphorus Impacts To Periphyton In Ozark Streams, Ashley Renee Rodman

Graduate Theses and Dissertations

Stream bioassessment is important for understanding algal-nutrient relationships and the development of scientifically defensible numeric nutrient criteria. However, multiple methods of periphyton data collection are currently used, and little is known about the comparability of resulting datasets. Literature also suggests other factors besides nutrients (i.e. variable grazing, light, and flow) can confound algal-nutrient relationships. A one-year method comparison study and 31-day algal biomass-nutrient manipulative experiment were conducted in the southern Ozarks of Arkansas. The method comparison study was implemented using two common bioassessment procedures (whole-surface and delimiter-reduced periphyton removal) to assess the potential for combining datasets. During the manipulative experiment, …

Preserving Rice Quality: Fine-Mapping And Introgressing A Fissure Resistance Locus, Haley Marie Sater

Graduate Theses and Dissertations

Rice (Oryza sativa L.) kernel fissuring is a major concern of both rice producers and millers. Fissures are small cracks in rice kernels that increase breakage of kernels when milled, and decrease the value of processed rice. This study employed molecular gene tagging methods to fine-map a fissure resistance (FR) locus found in ‘Cybonnet’, a semidwarf tropical japonica cultivar, as well as transfer this trait to rice genotypes of taller, non-semidwarf plant height that are better adapted to some rice production systems. Three QTLs for FR were previously reported; the FR locus with strongest effect resides near the semidwarf sd-1 …

Viscous Liquids And The Glass Transition At Extremely High Pressure: Optical Techniques Applied To Cumene In A Diamond Anvil Cell, Timothy Craig Ransom

Graduate Theses and Dissertations

This dissertation presents the results from experiments studying the pressure-dependence of properties associated with the glass transition in the glass-forming liquid cumene. Through the use of a diamond anvil cell, we achieve extremely high pressures over 40,000 atmospheres. A new technique is refined to directly measure the glass transition temperature Tg extremely accurately, and we show that thermodynamic scaling is capable of describing the liquid�glass transition boundary up to record-high pressures. Optical techniques are also implemented to probe the system dynamics in the viscous regime leading up to the glass transition. We present laser light-scattering measurements of the dynamic susceptibility …

The Mass Flux Of Non-Renewable Energy For Humanity, Edwin Dale Solomon

Graduate Theses and Dissertations

The global energy supply relies on non-renewable energy sources, coal, crude oil, and natural gas, along with nuclear power from uranium and these finite resources are located within the upper few kilometers of the Earth’s crust. The total quantity of non-renewable energy resources consumed relative to the total quantity available is an essential question facing humanity. Analyses of energy consumption was conducted for the period 1800 – 2014 using data from the U. S. Energy Information Administration (EIA) and World Energy Production, 1800-1985 to determine the balance between non-renewable energy resources consumed and ultimately recoverable reserves. Annual energy consumption was …

The Maximal Thurston-Bennequin Number On Grid Number N Diagrams, Emily Goins Thomas

Graduate Theses and Dissertations

We will prove an upper bound for the Thurston-Bennequin number of Legendrian knots and links on a rectangular grid with arc index n.

TB(n)=CR(n)-[n/2]

In order to prove the bound, we will separate our work for when n is even and when n is odd. After we prove the upper bound, we will show that there are unique knots and links on each grid which achieve the upper bound. When n is even, torus links achieve the maximum, and when n is odd, torus knots achieve the maximum.

Enabling Usage Pattern-Based Logical Status Inference For Mobile Phones, Jon C. Hammer

Graduate Theses and Dissertations

Logical statuses of mobile users, such as isBusy and isAlone, are the key enabler for a plethora of context-aware mobile applications. While on-board hardware sensors (such as motion, proximity, and location sensors) have been extensively studied for logical status inference, continuous usage typically requires formidable energy consumption, which degrades the user experience. In this thesis, we argue that smartphone usage statistics can be used for logical status inference with negligible energy cost. To validate this argument, we present a continuous inference engine that (1) intercepts multiple operating system events, in particular foreground app, notifications, screen states, and connected networks; (2) …

Measuring Teacher Effectiveness: A Comparison Across Va Models Utilizing Arkansas Data, Kelli Lane Blackford

Graduate Theses and Dissertations

A shift in accountability systems from No Child Left Behind to a reauthorization of the Elementary and Secondary Education Act redefined the mandate of classroom teachers from being highly qualified to highly effective. Whereas previously, a teacher was deemed highly qualified for having a bachelor’s degree, full state certification, and demonstrated knowledge of subject matter in the field they teach, a highly effective teacher had to demonstrate their abilities to move a student at an acceptable rate of student growth (one grade level in an academic year). To provide this evidence, student assessment data was now going to be a …

Isotopic Identification Of Multiple Contributors Of Metal Ions In Mississippi Valley-Type Ore Deposits Along The Cincinnati Arch In South-Central Kentucky, William Travis Garmon

Graduate Theses and Dissertations

Mississippi Valley-Type (MVT) ores are economically-viable deposits of sulfide minerals, often dominated by sphalerite (zinc-sulfide) in carbonate facies, and galena (lead-sulfide) in siliciclastic facies. MVT ores precipitate from migrating fluids, which carry base metals often complexed with chlorine ions within a basinal brine. This study identifies metal-contributing source-regions of the Burkesville MVT deposit using Pb-isotope ratios within sphalerite samples collected from the Burkesville deposit. The deposit is found in south-central Kentucky within the Middle-Tennessee ore district along the crest of the Cincinnati Arch, which is the anticlinal divide between the Appalachian Basin and the Illinois Basin. Competing theories argue that …

Stratigraphic Interpretation And Reservoir Implications Of The Arbuckle Group (Cambrian-Ordovician) Using 3d Seismic, Osage County, Oklahoma, Ryan Marc Keeling

Graduate Theses and Dissertations

The Arbuckle Group in northeastern Oklahoma consists of multiple carbonate formations, along with several relatively thin sandstone units. The group is a part of the “Great American Carbonate Bank” of the mid-continent and can be found regionally as far east as the Arkoma Basin in Arkansas, and as far west as the Anadarko Basin in Oklahoma. The Arbuckle is part of the craton-wide Sauk sequence, which is both underlain and overlain by regional unconformities.

Arbuckle is not deposited directly on top of a source rock. In order for reservoirs within the Arbuckle to become charged with hydrocarbons, they must be …

Resolving Paragneiss Provenance At Grollier Lake In The Athabasca Granulite Terrane, Western Canadian Shield, Dustin Ply

Graduate Theses and Dissertations

U-Pb crystallization ages of metamorphic and detrital zircons from all three paragneiss samples fall into the range of ca. 1.85-2.59 Ga, excluding two much older grains. Evidence suggests that the paragneiss of Grollier Lake record deformation exclusively from the Taltson and Trans-Hudson orogenies. It is apparent from geochronological data that the Taltson orogeny played an exceedingly larger role in the deformation of these rocks than the Trans-Hudson. Deposition of the paragneiss protoliths most likely culminated between ca. 2037-1994 Ma with metamorphism ceasing by 1852.1 ± 11.1 Ma. The oldest overgrowth considered to be concordant is 1994 ± 12 Ma and …

Enabling Runtime Profiling To Hide And Exploit Heterogeneity Within Chip Heterogeneous Multiprocessor Systems (Chmps), Eugene Cartwright

Graduate Theses and Dissertations

The heterogeneity of multiprocessor systems on chip (MPSoC) has presented unique opportunities for furthering today’s diverse application needs. FPGA-based MPSoCs have the potential of bridging the gap between generality and specialization but has traditionally been limited to device experts. The flexibility of these systems can enable computation without compromise but can only be realized if this flexibility extends throughout the software stack. At the top of this stack, there has been significant effort for leveraging the heterogeneity of the architecture. However, the betterment of these abstractions are limited to what the bottom of the stack exposes: the runtime system.

The …

Effect Of Potassium Deficiency On Uptake And Partitioning In The Cotton (Gossypium Hirsutum L.) Plant And Detection By A Crop Reflectance Sensor, Taylor Dayne Coomer

Graduate Theses and Dissertations

For cotton (Gossypium hirsutum L.) to grow and develop normally, plants need to uptake the necessary amount of nutrients and use those nutrients in a beneficial fashion. It is recognized that cotton needs a certain tissue concentration of ions to achieve and maintain growth rates (Siddiqi et al., 1987). One of the most essential and abundant nutrients in cotton is potassium (K), second only by mass to nitrogen (N) (Marschner, 1995; Oosterhuis et al., 2013). Potassium exists in the soil in four separate pools and moves through soil to roots mainly through diffusion (Rengel & Damon, 2008; Samal et al., …

Data Partitioning Methods To Process Queries On Encrypted Databases On The Cloud, Osama M. Omran

Graduate Theses and Dissertations

Many features and advantages have been brought to organizations and computer users by Cloud computing. It allows different service providers to distribute many applications and services in an economical way. Consequently, many users and companies have begun using cloud computing. However, the users and companies are concerned about their data when data are stored and managed in the Cloud or outsourcing servers. The private data of individual users and companies is stored and managed by the service providers on the Cloud, which offers services on the other side of the Internet in terms of its users, and consequently results in …

Dietary Effects On The Stoichiometry Of Growth, Regulation, And Wastes Of Ozark Stream Insect Detritivores, Halvor Matthew Halvorson

Graduate Theses and Dissertations

A widespread stressor, anthropogenic nitrogen (N) and phosphorus (P) pollution can increase resource nutrient content and alter animal community composition in freshwater ecosystems. In this dissertation, I used ecological stoichiometry theory to examine effects of diet nutrient content and leaf litter type on growth, regulation, and wastes of aquatic invertebrate detritivores. I tested effects of leaf litter diet carbon:phosphorus (C:P) on growth and stoichiometric regulation of the detritivorous caddisfly Pycnopsyche lepida and used results to determine a threshold elemental ratio of oak litter C:P=1620 that confers peak growth of this species. This empirical, growth-based approach provided a more accurate estimate …

Exploring Privacy Leakage From The Resource Usage Patterns Of Mobile Apps, Amin Rois Sinung Nugroho

Graduate Theses and Dissertations

Due to the popularity of smart phones and mobile apps, a potential privacy risk with the usage of mobile apps is that, from the usage information of mobile apps (e.g., how many hours a user plays mobile games in each day), private information about a user’s living habits and personal activities can be inferred. To assess this risk, this thesis answers the following research question: can the type of a mobile app (e.g., email, web browsing, mobile game, music streaming, etc.) used by a user be inferred from the resource (e.g., CPU, memory, network, etc.) usage patterns of the mobile …

Statistical Analysis Of Fluvial Channel Belts, Kyle Ryan Spencer

Graduate Theses and Dissertations

As meandering rivers laterally migrate over time, they build channel belts. The accumulation of all previous flow paths creates the channel belt. To better understand these ancient rivers, modern river systems are being mapped to find statistical relationships between current flow path and the channel belt of river systems. It is important to examine a wide range of systems in terms of age, size, and location. The rivers are being mapped using an ImageJ, interpretations from Saucier (1994) and Google Earth. Three channel belt morphologies are mapped for 15 modern channel belts; the width of the river in relation to …

Social And Emotional Development And Language Outcomes In Mixed Income Preschool Classroom Environments, Misty D. Newcomb

Graduate Theses and Dissertations

Two different publicly funded preschool programs exist within Arkansas: Head Start and the Arkansas Better Chance (ABC) program. Though philosophically similar, the different programs have dramatically different income eligibility guidelines resulting in classrooms with differing levels of economic diversity. Independent samples t-tests were conducted on initial, final, and growth scores in Personal and Social Development and in the area of Language and Literacy Development. The program with higher income guidelines had higher initial and final scores, but mixed growth scores. Multiple regression analyses indicated that starting score was the single greatest predictor of growth and of final scores. Growth was …

Evaluation Of Rusle 2 To Estimate Soil Loss From Pastures, Stasha Katrina Balkissoon

Graduate Theses and Dissertations

The accurate estimation of soil erosion by the Revised Universal Soil Loss Equation version 2 (RUSLE2) is critical for several conservation assessments, least of which is its use in the Phosphorus Index (PI) to identify and rank the vulnerability of agricultural fields to phosphorus (P) runoff. Earlier versions of RUSLE reported a soil loss overestimation, which were revised to give RUSLE2, where biomass production in different climatic regions was more accurately represented. RUSLE version 2.0, which contains the new vegetative biomass production routine, was evaluated using two performance indices, the Nash Sutcliffe Efficiency Index (NSE) and Index of Agreement (D) …

Genotoxicity Of Graphene In Escherichia Coli, Ananya Sharma

Graduate Theses and Dissertations

Rapid advances in nanotechnology necessitate assessment of the safety of nanomaterials in the resulting products and applications. One key nanomaterial attracting much interest in many areas of science and technology is graphene. Graphene is a one atom thick carbon allotrope arranged in a two-dimensional honeycomb lattice. In addition to being extremely thin, graphene has several extraordinary physical properties such as its exceptional mechanical strength, thermal stability, and high electrical conductivity. Graphene itself is relatively chemically inert and therefore pristine graphene must undergo a process called functionalization, which is combination of chemical and physical treatments that change the properties of graphene, …

Identification Of Biomarkers For The Overall Survival Of Ovarian Cancer Patients, Kristi Mai

Graduate Theses and Dissertations

Rapid advance in sequencing technology has led to genome-wide analysis of genetic and epigenetic features simultaneously, making it possible to understand the biological mechanisms underlying cancer initiation and progression. However, how to identify important prognostic features poses a great challenge for both statistical modeling and computing. In this thesis, a network-based approach is applied to the Cancer Genome Atlas (TCGA) ovarian cancer data to identify important genes related to the overall survival of ovarian cancer patients. In the first step, a stepwise correlation-based selector is used to reduce the dimensionality of TCGA data, by filtering out a large number of …

Risk Estimation Toward A Natural History Model For Low Grade Glioma Patients, Anh Thi Hoang Pham

Graduate Theses and Dissertations

Glioma is a common type of primary brain tumor that represents 28% of all brain tumors and 80% of malignant tumors. According to a recent study by the Centers for Disease Control and Prevention (CDC), gliomas account for 53%, 35% and 29% of all brain tumors (68%, 74% and 81% of malignant brain tumors) among children (aged 0-14), teenagers (aged 15-19) and young adults, respectively. Gliomas are often diagnosed through radiological imaging and histopathology. There are two main groups of gliomas following World Health Organization’s classification: Low grade gliomas (LGG), or grade I and II gliomas; and high grade gliomas …

The Role Of Hydrologic Regimes In Driving Morphologic Divergence And The Trait Compositions Of Fish Assemblages, Lindsey A. Bruckerhoff

Graduate Theses and Dissertations

The hydrologic regime is an important determinant of the ecological integrity of a stream. Hydrologic regimes are defined by the magnitude, timing, frequency, rate of change, and duration of high and low flow events and capture long term patterns of variability and predictability of water movement in a stream. Flow regimes influence many aspects of the biophysical environment in lotic systems; therefore organisms have adapted to natural flow patterns. We investigated how fish have adapted to flow regimes at both a population and community level. In the first study presented in this thesis, we hypothesized fish exhibit phenotypic divergence to …

The Grey Men Of Empire: Framing Britain's Official Mind, 1854-1934, Blake Allen Duffield

Graduate Theses and Dissertations

“The Grey Men of Empire: Framing Britain’s Official Mind, 1854-1934,” examines the crucial, yet too often-undervalued role of Britain’s imperial bureaucracy in forging the ethos and identity behind the policy-decisions made across the Empire. Although historians have tended to dismiss them as the faceless and voiceless grey men of Empire, this study argues that the political officers of the Colonial Services represented the backbone of British colonial administration and, quite literally, were responsible for its survival and proliferation. These so-called ‘men on the spot’—the District Officers, Assistant District Officers, and Cadets of the C.S.—made innumerable day-to-day, minute-to-minute decisions free from …

Linear Trend Analysis: Implications For A Structural Fracture System And Applications Of Subsurface Fluid Migration, Northwest Arkansas And Eastern Oklahoma, Loren Labusch

Graduate Theses and Dissertations

Lineaments are mappable, simple or composite linear or curvilinear features of the Earth’s surface longer than one mile, which differ from the patterns of adjacent features and are presumed to reflect subsurface phenomenon such as faults and fractures. The usage of the term refers to the description Lattman published in 1958 and was the foundation for work by MacDonald in 1977, which is the basis for this project. Remote sensing techniques have provided a valuable means to analyze lineaments on a large scale in a relatively short time in comparison to field mapping methods. The products of such fracture studies …