Digital Commons Network^™

High Throughput Phenotypic Evaluation Of Drought-Related Traits In Soybean, Hua Bai

Graduate Theses and Dissertations

Drought limits crop growth and yield in soybean. Rapid and effective methods of screening large numbers of soybean lines for drought tolerance are urgently needed. Two experiments were conducted to evaluate the effects of drought in soybean during reproductive stages. In the first experiment five genotypes from maturity groups 2 through 5 were tested under well-irrigated and drought conditions. Beginning at R5, leaf samples were taken for nitrogen concentration analysis. Pictures were taken across the top of each plot to determine the intensity of greenness using the Dark Green Color Index (DGCI). Aerial photographs were also taken to determine aerial …

Recognition Training For Faces Across Age Gaps, William Blake Erickson

Graduate Theses and Dissertations

Face recognition is a problem that has theoretical and applied value. However, the fact of facial aging is rarely addressed in research and unmentioned in the major theories of face recognition. Facial aging also has ramifications for missing persons and fugitive cases, confounding attempts by law enforcement to recover these people whose last known images are years or decades out of date. This dissertation reports three studies aimed at measuring baseline age-gap recognition ability and testing various training regimens designed to increase accuracy rates for this unique kind of recognition task.

Chlorine Demand Shows Thresholds And Hierarchy With Source Water Quality At Beaver Lake, Arkansas, Jaime M. Gile

Graduate Theses and Dissertations

This study investigated the effects of source water quality in Beaver Lake on the amount of chlorine (Cl) needed to develop decision support system to help guide chlorination practices in pre-treatment of source water. Chlorine demand assays were performed on water samples from Beaver Lake collected from the intake structure at Beaver Water District from March 2014 through August 2015, and using data from these assays, the two points of interest in this study were the Cl dose at which Cl residuals began to accumulate and the mean Cl demand occurring after that dose. Three methods of analysis were used …

Analysis Of Bridge Deck Sections By Pseudo-Compressibility Method Based On Fdm And Les: Improving Performance Through Implementation Of Parallel Computing, Blandine Therese Mbianda Kemayou

Graduate Theses and Dissertations

The incidence of wind on bridges produces static and dynamic loading that must be adequately addressed when designing bridges. Dynamic loading is the primary concern, as the amplitude of the structures response to the applied loading may be greatly amplified. Ideally, the bridge's properties should be designed to avoid dynamic loading. Previous investigations of wind loading on bridges consisted of measuring forces produced on scaled models of bridges within wind tunnels. However, these wind tunnel tests are costly and time consuming due to cost to fabricate and instrument the bridge cross sections. Recent advancements in computational power of computers allow …

Quantification And Characterization Of Fracture Resistance In Asphalt Concrete Based On R-Curve Method, Shu Yang

Graduate Theses and Dissertations

The application of fracture energy is widely applied in the evaluation of cracking in the laboratory for asphalt concrete. However, this single number does not provide information on the characterization of the initiation and propagation of cracks. The Resistance Curve method, or R-Curve, is widely applied in characterizing various materials including, but not limited to, metal, polymer, rock, and composite. This research R-Curve method introduces asphalt concrete through a stepwise approach. First, in chapter one, there is a literature review of the history of fracture mechanics, fracture research in asphalt concrete, and an examination of the role of R-Curve application …

Quantifying, Assessing, And Mitigating Methane Emissions From Super-Emitters In The Oil And Gas Supply Chain, David Richard Lyon

Graduate Theses and Dissertations

Methane emissions from the oil and gas (O&G) supply chain reduce potential climate benefits of natural gas as a replacement for other fossil fuels that emit more carbon dioxide per energy produced. O&G facilities have skewed emission rate distributions with a small fraction of sites contributing the majority of emissions. Knowledge of the identity and cause of these high emission facilities, referred to as super-emitters or fat-tail sources, is critical for reducing supply chain emissions. This dissertation addresses the quantification of super-emitter emissions, assessment of their prevalence and relationship to site characteristics, and mitigation with continuous leak detection systems. Chapter …

Exploring The Black Space Of Compressive And Shear Modulus, Airam Marlee Morales Vega

Graduate Theses and Dissertations

Uniaxial dynamic modulus is a standard test used to determine the viscoelastic behavior of asphalt pavement materials, with the standard analysis generating a Master Curve. One alternative to the master curve approach is a Black Space diagram, which is a rheological plot that can delineate either dynamic modulus |E*| or shear modulus |G*| vs. phase angle (δ). In this study, four asphalt binders were tested with one aggregate blend. One of these four binders was unmodified and the other three were modified with polymers and acids. Additionally, Polyphosphoric acid (PPA) is compared to the more traditional SBS polymer modification. PPA …

Impact Of Extreme Summer Temperatures On Bridge Structures, Ryan Hagedorn

Graduate Theses and Dissertations

Climate change and its effect on weather in the United States is a well-documented phenomenon. In particular, extreme heat waves have become more intense, more frequent, and longer lasting, especially in the southern United States. As with much of America’s transportation infrastructure, prestressed concrete bridge girders experience the effects of these heat waves. Uneven heating of optimized bridge girder sections results in large non-linear temperature gradients. In this study, temperature was monitored in three different AASHTO I-girders to determine the vertical and transverse temperature gradients in a pre-deck placement condition. It was determined that the current design standard, which uses …

Algal Wastewater Treatment And Biofuel Production: An Assessment Of Measurement Methods, And Impact Of Nutrient Availability And Species Composition, John F. Chamberlin

Graduate Theses and Dissertations

In order to move towards a more sustainable future, human civilization will need to decrease its impacts on air and water quality and minimize consumption of fossil fuels. Using algae for wastewater treatment and biofuel production offers one approach to progress towards these goals simultaneously. Algae are capable of removing nutrients from wastewater and carbon dioxide from the air, and the biomass formed in that process can be used to generate a wide-range of products including fertilizer or fuels that could power combustion engines, power plants, or zero-emission fuel cell vehicles. Using wastewater for biofuel production has the potential to …

Nanofiltration Rejection Of Contaminants Of Emerging Concern From Municipal Water Resource Recovery Facility Secondary Effluents For Potable Reuse Applications, Steven Michael Jones

Graduate Theses and Dissertations

As reuse of municipal water resource recovery facility (WRRF) effluent becomes vital to augment diminishing fresh drinking water resources, concern exists that conventional barriers may prove deficient and the upcycling of contaminants of emerging concern (CECs) could prove harmful to human health and aquatic species if more effective and robust treatment barriers are not in place.

There are no federal Safe Drinking Water Act (SDWA) regulations in place specifically for direct potable reuse (DPR) of WRRF effluent. Out of necessity, some states are developing their own DPR reuse regulations. Currently, reverse osmosis (RO) is the default full advanced treatment (FAT) …

Structural Identification Of An Elevated Water Tower, James Thomas Norris

Graduate Theses and Dissertations

Elevated water tanks are generally located at higher elevations within a particular geographic area. The location and height of these structures often makes them desirable for installing wireless and cellular communications antennas. The impact of this practice on the long-term serviceability performance of the primary structure is not clear and could be an important consideration deserving further analysis. This paper presents a case study of an elevated water tank that was motivated by this particular consideration. The structure had been retrofitted with cellular antennas during its service and later experienced fatigue cracking at the fill pipe-tank interface. The owner wished …

Evaluation Of Poisson’S Ratio Of Asphalt Concrete, Elvis Alexander Castillo Camarena

Graduate Theses and Dissertations

Poisson´s ratio can be defined as the negative ratio of strains perpendicular to the load direction to the strains parallel to the loading direction. If elastic or viscoelastic models are used, Poisson´s ratio, together with elastic modulus, is a main input used to predict distresses in flexible pavement structures such as rutting and cracking. In asphalt concrete, Poisson’s ratio is commonly measured using two different testing configurations: indirect tension (IDT) and uniaxial. However, results from these two testing configuration can potentially have differences. Design methodologies such as the Mechanistic Empirical Design Guide (MEPDG, now PavementME) have been shown to be …

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 …

Development Of The Masw Method For Pavement Evaluation, Benjamin J. Davis

Graduate Theses and Dissertations

The purpose of this research is to establish a recommended procedure for performing multichannel analysis of surface waves (MASW) on pavements as well as evaluating the ability of MASW to detect a change in shear wave velocity as damage in concrete increases. The tests for establishing a recommended procedure for performing MASW on pavements was conducted at five sites at the University of Arkansas Engineering Research Center in Fayetteville, Arkansas. The five sites consisted of three materials: asphalt, concrete, and soil (two sites were on asphalt, two were on concrete, and one was on soil). The methods evaluated at these …

Prevention Of Drone Jamming Using Hardware Sandboxing, Joshua Mead

Graduate Theses and Dissertations

In this thesis, we concern ourselves with the security of drone systems under jamming-based attacks. We explore a relatively new concept we previously devised, known as hardware sandboxing, to provide runtime monitoring of boundary signals and isolation through resource virtualization for non-trusted system-on-chip (SoC) components. The focus of this thesis is the synthesis of this design and structure with the anti-jamming, security needs of drone systems. We utilize Field Programmable Gate Array (FPGA) based development and target embedded Linux for our hardware sandbox and drone hardware/software system.

We design and implement our working concept on the Digilent Zybo FPGA, which …

Development Of Infrared Heating Technology For Corn Drying And Decontamination To Maintain Quality And Prevent Mycotoxins, Shantae Wilson

Graduate Theses and Dissertations

Infrared (IR) heating of corn followed by tempering treatments has potential to rapidly dry and simultaneously decontaminate corn without adverse effect on the overall quality. However, it is vital to determine the optimal processing parameters that maximize throughput and minimize drying energy without affecting overall corn quality. This study investigated the effects of IR heating and tempering treatments on moisture removal, mold load reduction, corn color change, and drying energy requirements. In addition, the study evaluated the feasibility of scaling up IR drying process using a newly built, pilot scale IR dryer. Freshly harvested corn with initial moisture content (IMC) …

Validation Of A Confocal Light Sheet Microscope Using Push Broom Translation For Biomedical Applications, Joshua Hutcheson

Graduate Theses and Dissertations

There exists a need for research of optical methods capable of image cytometry suitable for point-of-care technology. To propose am optical approach with no moving parts for simplification of mechanical components for the further development of the technology to the poin-of-care, a linear sensor with push broom translation method. Push broom translation is a method of moving objects by the sensor for an extended field of view. A polydimethylsiloxane (PDMS) microfluidic chamber with a syringe pump was used to deliver objects by the sensor. The volumetric rate of the pump was correlated to the integration time of the sensor to …

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 …

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) …

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 …

Essays In Physicians Preference Items And Inventory Management Within The Healthcare Supply Chain, Mohammad A. Shbool

Graduate Theses and Dissertations

This work is composed of a number of topics in the healthcare area, which are approached separately with appropriate methodologies. The two topics deal with physician preference items via two different approaches. The first one investigates stock keeping unit (SKU) proliferation in healthcare organizations due to physician preference items (PPI). It captures perspectives of physicians and supply chain professionals about this problem through two surveys. The second topic builds a decision-making framework for the PPI selection process that can be used by healthcare organizations to make more objective decisions. A Multi-criteria decision making technique is implemented to illustrate the framework.

Trade And Transport In Late Roman Syria, Christopher Wade Fletcher

Graduate Theses and Dissertations

Despite the relative notoriety and miraculous level of preservation of the Dead Cities of Syria, fundamental questions of economic and subsistence viability remain unanswered. In the 1950s Georges Tchalenko theorized that these sites relied on intensive olive monoculture to mass export olive oil to urban centers. Later excavations discovered widespread cultivation of grains, fruit, and beans which directly contradicted Tchalenko’s assertion of sole reliance on oleoculture. However, innumerable olive presses in and around the Dead Cities still speak to a strong tradition of olive production. This thesis tests the logistical viability of olive oil transportation from the Dead Cities to …

Production And Application Of Trans, Trans Cla-Rich Eggs: Chemical And Physiological Properties And Prospects For Value-Added Foods, Sara Shinn

Graduate Theses and Dissertations

Conjugated linoleic acid (CLA) is an 18-carbon fatty acid with conjugated double bonds that is naturally present in beef and dairy products. Certain CLA isomers exhibit human bioactivity such as anti-obesity and muscle metabolism effects, as well as prevention of age-associated conditions, and improved immune and inflammatory responses. However, an individual needs to consume 3-4 g CLA/day to realize these potential health benefits, and a Western diet only provides a tenth of this recommendation. Chicken eggs have been used as a commercialized vehicle to deliver other bioactive lipids such as omega-3 fatty acids, because the lipid profile of the egg …

Divining The Southwest: Liminality, Pragmatism, And Regionalism In "Death Comes For The Archbishop", Alex C. Blomstedt

Graduate Theses and Dissertations

This work aims to explore the themes of pragmatism and liminality, particularly as they pertain to spirituality, in Willa Cather’s Death Comes for the Archbishop. By taking an interdisciplinary critical approach to the novel, I will synthesize its spiritual affect into a sensibility called “pragmatic liminality.” Finally, I will connect this sensibility to other works in the Southwestern literary canon and elucidate the foundational importance that pragmatic liminality has to the Southwestern “sense of place” and its role in the larger narratives of regionalism in American literature.

Cloning, Fed-Batch Expression And Purification Of A Novel Anti-Candida Peptide And Development Of A Cleavage Resistant Variant Of Green Fluorescence Protein, Rudra Palash Mukherjee

Graduate Theses and Dissertations

This work illustrates that the intelligent design of a bioprocess for the production of peptides of various length is possible by having a prior knowledge of desired product, cell line, fermentation conditions, and choices for downstream recovery. Cloning, expression, and recovery of a novel 12-mer anti-Candida peptide served as an illustrative case for a proposed Escherichia coli platform. The antifungal peptide, expressed as a fusion to GFPUV during high call density fed-batch, was recovered from cell lysate, concentrated using ion exchange chromatography, and finally cleaved with cyanogen bromide. The platform was capable of producing active peptide capable of arresting the …

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) …

Control Design Of A Single-Phase Dc/Ac Inverter For Pv Applications, Haoyan Liu

Graduate Theses and Dissertations

This thesis presents controller designs of a 2 kVA single-phase inverter for photovoltaic (PV) applications. The demand for better controller designs is constantly rising as the renewable energy market continues to rapidly grow. Some background research has been done on solar energy, PV inverter configurations, inverter control design, and hardware component selection. Controllers are designed both for stand-alone and grid-connected modes of operation. For stand-alone inverter control, the outer control loop regulates the filter capacitor voltage. Combining the synchronous frame outer control loop with the capacitor current feedback inner control loop, the system can achieve both zero steady-state error and …

Genetic Analysis Of Soybean Mosaic Virus (Smv) Resistance Genes In Soybean [Glycine Max (L.) Merr.], Mariola Klepadlo

Graduate Theses and Dissertations

Soybean mosaic virus (SMV) causes the most serious viral disease in soybean worldwide. Seven SMV strains, G1 - G7, and three independent multi-allelic loci for SMV resistance, Rsv1, Rsv3, and Rsv4, have been identified. In the initial study, 299 soybean germplasm lines were genotyped for Rsv4 region, inoculated with SMV-G1 and G7 strains, and classified into several resistance groups. The Glyma.02g121400 locus was sequenced from ten soybean accessions, and alignment of the sequences revealed three SNPs displaying 100% polymorphic consistency when a soybean genotype carrying the Rsv4 gene was present. A cross between V94-5152 × Lee 68 was made to …

Use Of Response Surfaces In The Design Of A Simple Step Stress Accelerated Test Plan, Alexander H. Wong

Graduate Theses and Dissertations

In designing accelerated testing plans, cost is a factor that is missing in much of the literature. This paper explicits considers cost by developing an optimization model with the objective to minimize costs for a simple step stress accelerated test plan. Two methodologies are employed. One is an optimization approach in which an attempt is made to quantify the behavior of a series-parallel hardware system over all stages of testing using a response surface, and then an optimization model is used to determine the settings for stresses and failure mode modifications for all stages of testing prior to the start …

Dandy As Disease: Gender Hygiene And British Nineteenth-Century Literature, Sharon Louise Fox

Graduate Theses and Dissertations

“Dandy as Disease: Gender Hygiene and British Nineteenth-century Literature” explores the link between the nineteenth-century dandy, ideas of hegemonic masculinity, and Walter Besant’s The Revolt of Man, a dystopian text in which women have usurped all traditionally-masculine roles, while men are the caretakers and manual workers. The first chapter deals with the historical role of the dandy in the nineteenth-century and how he might be viewed as the cause of the fall of Britain. The second chapter revolves around Besant’s novel, exploring how men are shown to be at fault for Britain’s fall in the eyes of the rest of …