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Dynamic Electron-Phonon Interactions In One Dimensional Models, Rahul Padmakar Hardikar

Theses and Dissertations

We study the unusual phases seen in charge transfer salts (CTS) at 1/2 and 1/4 filling. We use the Holstein-Hubbard model (HHM) and the Peierls extended Hubbard model (PEH) to study competing phases in CTS. In the 1/2illed HHM the Holstein coupling promotes a Peierls charge-density wave phase while the on-site Coulomb repulsion U gives rise to antiferromagnetic correlations and a Mott insulating state. Takada et al. have shown possibility of a third metallic phase between the Mott and the Peierls phase. We investigate the presence of an intermediate phase between the Mott and Peierls phase using Stochastic Series Expansion …

Full Scale Instrumented Testing And Analysis Of Matting Systems For Airfield Parking Ramps And Taxiways, Chad A. Gartrell

Theses and Dissertations

The U.S. military requires the ability to rapidly deploy troops, equipment, and materials anywhere in the world. Recent operations have brought attention to the need to utilize austere, unsurfaced, and sometimes sub-standard airfields within a theater of interest. These airfields may require additional taxiways and aprons. One option for the rapid construction of such is airfield matting systems. The focus of the work for this thesis was commercially available airfield matting systems to support large military transport aircraft, such as the C 17. Several test sections with differing strength soils were built with chosen mats tested in an elimination method, …

Development Of A Tungsten Carbide-Nickel Braze Alloy Hardface Coating, Travis Earl Puzz

Theses and Dissertations

If an expensive part such a turbine blade or high quality tool needed to be refurbished instead of discarded, the part would have be coated in a way that would resemble or even exceed its previous surface properties. In this regard, this work studies a tungsten carbide-nickel braze alloy hardface composite prepared by liquid infiltration. A unique polymeric binder system was used to form the brazing cloth which formed the carrier for the tungsten carbide and nickel braze alloy particles. After thermal pyrolysis of the binder, the nickel braze alloy would infiltrate into a porous tungsten carbide layer becoming a …

Development Of Bio-Photonic Sensor Based On Laser-Induced Fluorescence, Chan Kyu Kim

Theses and Dissertations

Laser-induced fluorescence (LIF) has been shown to be potentially useful for identifying microorganisms in real time. It is a selective and sensitive technique because the excitation is performed at one wavelength while the emission is monitored at longer wavelengths so that background from the excitation source can be eliminated. This specialized optical property of LIF can be applied to development of an optical sensor capable of quickly, non-invasively, and quantitatively probing complex biochemical transformations in microorganisms. Various bio-photonic optical fiber sensors based on laser-induced fluorescence (LIF) spectroscopy were developed as diagnostic tools for microorganisms. In the first phase, the enhancement …

Dielectrophoretic Characterization Of Abo Blood Type, Frequency And Ac Field Strength Of Erythrocytes, Prashant Reuben Daggolu

Theses and Dissertations

This research investigates the role of ABO blood type of erythrocytes in their dielectrophoretic response. The dielectrophoresis of erythrocytes of positive ABO blood types was studied at 5 V (peak to peak) and 1 MHz frequency AC field. The study revealed that the ABO blood type had an influence on the dielectrophoretic motion of the erythrocytes, particularly separating AB+ and O+ blood types. This is of particular significance since AB+ is a universal acceptor and O+ is a universal donor for blood transfusion purposes. The influence of field parameters, namely field strength and frequency of the AC field, was also …

Central Crops And Soils Research Station Highmore, South Dakota: Annual Progress Report, 2007, Agricultural Experiment Station, Plant Science Department

Agricultural Experiment Station and Research Farm Annual Reports

This is the 2007 progress report for the Central Crops and Soils Research Station at Highmore, South Dakota State College. This document represents the research conducted at the Station during the 2007 crop season including: temperature and precipitation data, evaluation of native and naturalized grasses for reduced-input turf in the Northern Plains, 2006 NTEP tall fescue ancillary trial for drought tolerance, sunflower evaluation for resistance to the red sunflower seed weevil, weed control, alfalfa production, and spring-seeded small grains- 2007 eastern South Dakota variety test results, herbicide programs and experiments.

2007 Fall Commencement, Harding University

Commencement Programs

Program for the Commencement on December 15.

Commencement Speaker: Howard Wright

Disease Management Strategies For Controlling Spring Dead Spot And Frequency Of Occurrence Of The Causal Organism Ophiosphaerella Korrae On 'Tifway' Bermudagrass (Cynodon Dactylon X C. Transvaalensis), Hunter D. Perry

Theses and Dissertations

Spring dead spot (SDS) is the most destructive disease of bermudagrass and its hybrids, affecting intensively managed bermudagrass turf that is at least three years old. This bermudagrass disease is most prevalent in the United States where winter temperatures become cold enough to induce dormancy. The symptoms of SDS appear as sunken, necrotic patches of turf ranging from several centimeters to greater than 0.5 m in diameter. Field studies were conducted at Old Waverly Golf Club in West Point, MS on a Tifway bermudagrass fairway beginning January of 2005 and concluding December of 2006 to determine the frequency and the …

Microstructure-Property Relations Throughout The Powder Metallurgy Process, Laura Arias Tucker

Theses and Dissertations

To produce crack free powder compacts with desirable mechanical properties and uniform densities, a predictive finite element simulation of the powder metallurgy process is necessary (compaction and sintering). The finite element method, through the use of appropriate constitutive material models captures the microstructure-property history after compaction and sintering. A FC-0205 cylinder and FC-0208 automotive main bearing cap were compacted to investigate the microstructure changes at different locations within the parts. Measurements of the pore volume fraction, pore size, pore nearest neighbor, pore aspect ratio, and grain size were performed after compaction for the cylinder after compaction and after compaction and …

Non-Equilibrium Surface Growth For Competitive Growth Models And Applications To Conservative Parallel Discrete Event Simulations, Poonam Santosh Verma

Theses and Dissertations

Non-equilibrium surface growth for competitive growth models in (1+1) dimensions, particularly mixing random deposition (RD) with correlated growth process which occur with probability $p$ are studied. The composite mixtures are found to be in the universality class of the correlated growth process, and a nonuniversal exponent $\delta$ is identified in the scaling in $p$. The only effects of the RD admixture are dilations of the time and height scales which result in a slowdown of the dynamics of building up the correlations. The bulk morphology is taken into account and is reflected in the surface roughening, as well as the …

Flexural And Tensile Properties Of Thin, Very High-Strength, Fiber-Reinforced Concrete Panels, Michael Jason Roth

Theses and Dissertations

This research was conducted to characterize the flexural and tensile characteristics of thin, very high-strength, discontinuously reinforced concrete panels developed by the U.S. Army Engineer Research and Development Center. Panels were produced from a unique blend of cementitous material and fiberglass reinforcing fibers, achieving compressive strength and fracture toughness levels that far exceeded that of typical concrete.The research program included third-point flexural experiments, novel direct tension experiments, implementation of micromechanically based analytical models, and development of finite element numerical models. The experimental, analytical, and numerical efforts were used conjunctively to determine parameters such as elastic modulus, first-crack strength, post-crack modulus …

Hydrodynamic Modeling Of Impact Craters In Ice, Jesse Andrew Sherburn

Theses and Dissertations

In this study, impact craters in water ice are modeled using the hydrodynamic code CTH. In order to capture impact craters in ice an equation of state and a material model are created and validated. The validation of the material model required simulating the Split Pressure Hopkinson Bar (SPHB) experimental apparatus. The SPHB simulation was first compared to experiments completed on Al 6061-T6, then the ice material model was validated. After validation, the cratering simulations modeled known experiments found in the literature. The cratering simulations captured the bulk physical aspects of the experimental craters, and the differences are described. Analysis …

Influence Of Source/Drain Residual Implant Lattice Damage Traps On Silicon Carbide Metal Semiconductor Field Effect Transistor Drain I-V Characteristics, John Adjaye

Theses and Dissertations

4H-SiC n-channel power MESFETs with nitrogen-doped epitaxially grown channel and nitrogen n+-implanted source/drain ohmic contact regions, with and without p-buffer layer fabricated on semi-insulating substrates exhibited hysteresis in the drain I-V characteristics of both types of devices at 300 K and 480 K due to traps. However, thermal spectroscopic measurements could detect the traps only in the devices without p-buffer. In this study the two-dimensional device simulator, MediciTM, and optical admittance spectroscopy (OAS) measurements are used to help resolve the discrepancy in the initial experimental characterization results and interpret the results. Device simulations also showed hysteresis in the drain I-V …

Selection For Reduced Seed Dormancy In Seven Native Grass Species, Kyle Bradley Holmberg

Theses and Dissertations

Lowland switchgrass (Panicum virgatum), big bluestem (Andropogon gerardii), indiangrass (Sorghastrum nutans), upland switchgrass (Panicum virgatum), little bluestem (Schizachyrium scoparium), beaked panicum (Panicum capillare), and purpletop (Tridens flavus) all show strong signs of seed dormancy which contributes to extremely poor field establishment. The objective of this work was to reduce seed dormancy by selecting individuals that exhibited reduced pre-stratification dormancy in laboratory tests. The classical breeding method of phenotypic recurrent selection was used to enhance germination. Of the three tall-stature species, lowland switchgrass made the greatest improvement in pre-stratification germination, followed by indiangrass and big bluestem. The four short stature species …

Watermarking With Wavelet Transforms, Kristen Michelle Parker

Theses and Dissertations

Digital watermarking algorithms based on wavelet transforms provide increased performance and perceptual quality. This thesis proposes two wavelet-based schemes: one robust and one fragile. Robust watermarks should withstand attacks, such as compression, while maintaining the data integrity. The first approach presented is an algorithm which implements image watermarking in the domain of an overcomplete, or redundant, wavelet transform. Alternately, fragile watermarks are intended for use in applications wherein any loss of image quality is not acceptable. In the second approach presented, data embedding in the domain of an integer wavelet transform is considered. An algorithm is proposed that uses a …

Energy Storage System Requirements For Shipboard Power Systems Supplying Pulsed Power Loads, Prashanth Duvoor

Theses and Dissertations

Energy storage systems will likely be needed for future shipboard power systems that supply loads with high power variability such as pulsed power loads. The power generation in shipboard power systems may not be sufficient to satisfy the energy demands of the pulsed power load systems operating in conjunction with other ship service loads. Two fundamental items in evaluating the requirements of an energy storage system are the energy storage capacity and the ratings of the power conversion equipment that interfaces the energy device to the power system. The supply current of pulsed power load systems is aperiodic and cannot …

Evaluation Of A Low Profile Cascade Aerator, Chukwukelue Kenneth Monwuba

Theses and Dissertations

The aeration potential of a low profile cascade aerator was studied under varying operational conditions in accordance with the ASCE Standard for Measurement of Oxygen Transfer in Clean Water [ASCE 2-06, 2007]. Operational parameters delved into included the channel slope (2.50, 4.50 and 6.50); water flow rate (465.75 L/min.m (37.5 gpm/ft), 931.45 L/min.m (75 gpm/ft) and 1397.20 L/min.m (112.5 gpm/ft)); and weir geometry (rectangular-shaped, inverted T-shaped, W-shaped and inverted Cross shaped weir). The oxygen transfer coefficient, KLa, was derived by use of a FORTRAN-based nonlinear regression analysis computer program and served to assess the effectiveness of various combinations of operational …

Laser Induced Breakdown Spectroscopy: Investigation Of Line Profiles, Slurries And Artifical [Sic] Neural Network Prediction, Seong Yong Oh

Theses and Dissertations

Laser induced breakdown spectroscopy (LIBS) was tested to examine its applicability to remote and in suit analysis in inaccessible situation. Two types of liquid sample (slurry) prepared for simulating vitrification of liquid hazardous wastes was tested. In situ analysis ability makes the LIBS technique practical for analysis of the slurry samples during vitrification, which is in inaccessible situation. For the first slurry sample, two slurry circulation systems were devised to overcome major technical problems associated with LIBS measurements of slurry samples - namely sedimentation and change in the lens-to-sample distance (L.T.S.D) during measurement. The second slurry sample contained less water …

Micro-Structural Response Of Dp 600 To High Strain Rate Deformation, Brian Fredrick Hamburg

Theses and Dissertations

The object of this study was to investigate the micro-structural response of DP 600 subjected to high strain rate, ballistic impact tests. The ballistic tests were conducted using normal impact of a hardened steel penetrator into a 2 mm thick sheet of DP 600. The average strain rates produced from this test method are on the order of 10^5 s-1. Multiple methods were used to investigate the micro-structure before and after high strain rate deformation including optical microscopy, electron microscopy, and X-ray diffraction. A large variation in material response was observed between tests conducted at 0.8 x 10^5 and 2.5 …

Lb_Migrate: A Dynamic Load Balancing Library For Scientific Applications, Rohit Kailash Chaube

Theses and Dissertations

Parallel and distributed environments are used to solve large scientific and engineering problems that often are irregular and data parallel. However, performance of many parallel applications is affected by computation overheads, communication time and load imbalance. Among these factors, load imbalance is caused by the irregular nature of the problem, its algorithm, the difference in processor characteristics, and runtime loads. A number of applications achieve load balancing by one-time assignment of task. However, a number of applications have workloads that are unpredictable, and vary over the course of their execution. For such type of applications, load balancing is achieved by …

The Vehicle Routing Problem With Simultaneous Pick-Up And Deliveries And A Grasp-Ga Based Solution Heuristic, Arif Volkan Vural

Theses and Dissertations

In this dissertation, the vehicle routing problem and one of its variants, the vehicle routing problem with simultaneous pick up and deliveries (VRPSPD) are studied. The traditional vehicle routing problem (VRP) consists of constructing minimum cost routes for the vehicles to follow so that the set of customers are visited only once. A lot of effort has been devoted to research on developing fast and effective solution methods for many different versions of this problem by different majors of engineering profession. Thus, a structuring effort is needed to organize and document the vast literature so far has accumulated in this …

Effect Of Sparger Design On Hydrodynamics Of A Gas Recirculation Anaerobic Bioreactor, Rajneesh Varma, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

The Effects of Sparger Design and Gas Flow Rate On, Gas Holdup Distribution and Liquid (Slurry) Recirculation Velocity Have Been Studied in a Surrogate Anaerobic Bioreactor Used for Treating Bovine Waste with a Conical Bottom Mixed by Gas Recirculation. a Single Orifice Sparger (SOS) and a Multi-Orifice Ring Sparger (MORS) with the Same Orifice Open Area and Gas Flow Rates (Hence the Same Process Power Input) Are Compared in This Study. the Advanced Non-Invasive Techniques of Computer Automated Tomography (CT) and Computer Automated Radioactive Particle Tracking (CARPT) Were Employed to Determine Gas Holdup, Liquid Recirculation Velocity, and the Poorly Mixed …

Factors That Influcence African Americans To Enroll In Agricultural Science Programs, Levar Desmond Graham

Theses and Dissertations

The purpose of this study is to identify the factors that most influence African Americans to enroll in agricultural science programs at 1890 and 1862 Land Grant universities. This study used a quantitative approach in researching the problem of identifying the factors that led minorities to enroll in agricultural science programs at 1862 and 1890 land-grant institutions. A survey instrument was designed which collected the factors, demographics, and attitudes that influenced minority enrollment in agricultural sciences at 1890 and 1862 universities. The setting for the data collection in this study is 1890 and 1862 land grant universities in the southern …

Interview No. 1393, Ángel Guzmán Domínguez

Combined Interviews

Mr. Guzmán talks about growing up, including his family and learning how to make shoes; one of his uncles served in the bracero program, which convinced him to do the same; in 1944, he and five of his friends traveled by boat, bus and train before finally arriving at the contacting station in Queretaro, México; with the proper documentation, he was quickly called and passed all the medical exams; he explains that the men in Queretaro went straight to the railroads, while those processed in Guanajuato, México, went to work in the fields; from the contracting center he was transported …

An Evaluation Of Perceptions Of A Mentoring Program Of Beginning Teachers In A Rural East Tennessee Secondary School., Mike Frazier

Electronic Theses and Dissertations

Teachers, especially beginning teachers, continue a trend of leaving the profession at alarming rates within the first 5 years resulting in excessive costs to school systems and diminished instructional quality. Some programs, however, have shown impressive results. The purpose of this qualitative study, using an emerging interview process, was to examine the perceptions of beginning teachers in their 1st or 2nd year and those of veteran 3- to 5-year teachers regarding the effectiveness of mentoring and other guidance they received as beginning teachers in a secondary school and to understand their vision of how mentoring should be structured for beginning …

And This, Our Measure: Figurative Realism And Workaday Culture., Perry Walter Johnson

Electronic Theses and Dissertations

Man has created vast and powerful systems. These systems and their associated protocols, dogmas, and conventions tend to limit rather than liberate. Evaluation based on homogeneity threatens the devaluation of our humanity. This paper and the artwork it supports examine contemporary culture and its failings in the stewardship of the humanist ideal.

My paintings referenced herein are satirical narratives. The story told is one of alienation and evisceration. The visual subject matter is the human figure and environments dominated by architectural geometry. The male figures are conspicuously turned from view, a visual cue to their estrangement. Parallel and subordinate thoughts …

Self-Management Of Type 2 Diabetes In Appalachina Women., Melissa Joy Magness

Electronic Theses and Dissertations

Gender, minority, and regional-related disparities have been documented in diabetes management. Self-efficacy, the belief in one's ability to carry out the actions mandated by a task, has been identified as a key predictor in glycemic control; however, it has not been investigated in rural, female populations. This cross-sectional, correlation investigation examined the relationships among self-efficacy, depression, and diabetes self-care management in women living in Appalachia with type 2 diabetes. Using Bandura's Social Cognitive Theory, 85 women ages ≥ 21 with type 2 diabetes for a minimum of 6 months who were residents in Appalachia completed the 1) Diabetes Self-Efficacy Scale, …

Decomposition, Packings And Coverings Of Complete Digraphs With A Transitive-Triple And A Pendant Arc., Janice Gail Lewenczuk

Electronic Theses and Dissertations

In the study of design theory, there are eight orientations of the complete graph on three vertices with a pendant edge, K₃∪{e}. Two of these are the 3-circuit with a pendant arc and the other six are transitive triples with a pendant arc. Necessary and sufficient conditions are given for decompositions, packings and coverings of the complete digraph with each of the six transitive triples with a pendant arc.

Light Image Therapy In The Health Care Environment., Anna Rae Dutro

Electronic Theses and Dissertations

Use of positive distraction in the built healthcare environment to assist in alleviating stress in a patient was investigated. A backlit light image was mounted in the ceiling of an examination room to create a positive distraction for patients in the ETSU Pediatric Clinic in Johnson City, TN. Survey instruments were used to collect sample data from patients and physicians in a randomized, balanced controlled study designed to determine if patients experienced less stress in the room with the backlit image as compared to other rooms (treatments). Although a statistical difference was not determined between the room with the backlit …

1, Structural And Functional Studies Of Human Replication Protein A; 2 Dna Damage Responses And Dna Repair Defects In Laminopathy-Based Premature Aging., Yiyong Liu

Electronic Theses and Dissertations

The genome of mammalian cells is under constant attack from DNA-damaging agents. To maintain genomic integrity, cells activate an array of pathways primarily consisting of DNA repair and DNA damage checkpoints. Human replication protein A (RPA), a single-stranded DNA (ssDNA) binding protein, is essential for almost all DNA metabolic pathways. However, the role of RPA in nucleotide excision repair (NER), a DNA repair pathway for removing bulky DNA lesions, remains elusive. In this study, the binding of RPA to a battery of well-defined ssDNA substrates has been systematically examined using fluorescence spectroscopy. The results showed that RPA has a lower …