Digital Commons Network^™

Solar Technology In Our World- A Business Approach, Luke Ingalls Liska

Chancellor’s Honors Program Projects

No abstract provided.

Animal Welfare Around The World: Examining The Role The Economy Has On Animal Welfare, Olivia J. Thornton

Chancellor’s Honors Program Projects

No abstract provided.

Enhancing Usability Of The Multi-Channel Analysis Of Surface Wave (Masw) Technique For Subsurface Physical Property Mapping By Incorporating Random-Array Seismic Acquisition, Prasanta Malati Yeluru

Doctoral Dissertations

Subsurface imaging is very critical to exploit subsurface resources, monitor the fluid movement in the reservoir, mapping tunnels etc. As science advances scientists and other researchers are constantly trying to develop new techniques and methods for subsurface imaging that are more effective, efficient, and are more robust under varying field conditions. The main focus of this research is one such effort to improve and increase the usability of the Multi-channel Analysis of Surface Wave method (MASW) method in determining regolith and rock properties by introducing a new type of receiver arrangement to extend its usage in places that are inaccessible …

Work/Family Conflict As A Predictor Of Employee Work Engagement Of Extension Professionals, April B. Martin

Doctoral Dissertations

This study utilizes stress theory to explore the effects of work-family conflict and family-work conflict upon the work engagement outcomes of employees. Using a web-based questionnaire with a primary data sample of 2,782 full time Extension professionals in 46 states, this study incorporates the structural equation modeling analytic technique. This study confirmed the single, second order work-family conflict construct consisting of six first order constructs of work-family time, strain and behavior and family-work time, strain, and behavior. The bi-directionality of work-family conflict and family-work conflict was sustained, as numerous research studies have recommended. The structural equation modeling analysis found the …

The Relationship Between Broad And Narrow Personality Traits And Change Of Academic Major, Nancy A. Foster

Doctoral Dissertations

The purpose of this study was to investigate the relationship between personality traits and academic major change in two samples of college undergraduates. Utilizing a field study design, a total number of 859 undergraduates completed an online inventory that included the “Big Five” and other -related, narrow personality traits, as well as academic major change and various demographic variables. A number of expected and unexpected findings emerged. As hypothesized, the traits of Sense of Identity and Extraversion were significantly and negatively related to decisions to change major, but only for certain grade levels. Contrary to expectations, Career Decidedness and Optimism …

Analysis, Prototyping, And Design Of An Ionization Profile Monitor For The Spallation Neutron Source Accumulator Ring, Dirk A. Bartkoski

Doctoral Dissertations

The Spallation Neutron Source (SNS) located in the Oak Ridge National Laboratory is comprised of a 1 GeV linear H^- [H^-] accelerator followed by an accumulator ring that delivers high intensity 1 μs [microsecond] long pulses of 1.5x10¹⁴ [1.5x10^14] protons to a liquid mercury target for neutron production by spallation reaction. With its strict 0.01% total beam loss condition, planned power upgrade, and proposed second target station, SNS ring beam-profile diagnostics capable of monitoring evolving beam conditions during high-power conditions are crucial for efficient operation and improvement. By subjecting ionized electrons created during beam interactions with the residual …

The Advancement Of Bacterial Cellulose As A Bone And Vascular Scaffolds, Ryan Lee Hammonds

Doctoral Dissertations

Bacterial cellulose (BC) is a natural hydrogel made of nanofibers. This material has been used in commercial products, including wound dressings. BC can be modified and optimized for improved performance in multiple applications. This work will focus on producing and characterizing resorbable cellulose, a composite for bone applications, and a composite for a synthetic venous valve leaflet.

BC can be produced and modified to perform as a degradable tissue scaffold. This is achieved by an oxidation procedure after the initial production and purification of native BC. A material characterization of oxidized BC was performed to identify the changes in properties …

Understanding The Student Perspective Of Teacher-Student Engagement In First-Year Studies Courses, Anton R. Reece

Doctoral Dissertations

Higher education institutions continue to seek high impact retention methods to address student attrition, particularly during the first year of college. First-year studies courses represent a major institutional intervention and retention resource designed to help higher education institutions meet the unique academic and social needs of students transitioning from high school to college. Teacher-student engagement is considered to be an essential part of student retention efforts. However, most of the research on teacher-student engagement has focused on pedagogical strategies and the teachers’ perspectives of engagement. What is lacking in the literature are studies of students’ perspectives of classroom engagement. This …

Tracking Real-Time Nanoparticle Positions And Measuring Three-Dimensional Solution Flow With A Four-Focus Confocal Microscope, James Andrew Germann

Doctoral Dissertations

This dissertation presents the development of instrumentation for measuring the position of a single emitter within the sample volume of a confocal fluorescence microscope with sub-diffraction limited precision in three dimensions together with applications for determining solution flow and for tracking a fluorescent nanoparticle as it undergoes Brownian diffusion. The localization method is based on comparing photon counts from alternating excitation of the emitter by four laser beams, which are focused at slightly offset positions in a tetrahedral pattern within the confocal volume. Two experimental set-ups are constructed. In the first, the four beams are from a femtosecond laser, which …

A Viscous Flow Analog To Prandtl’S Optimized Lifting Line Theory Utilizing Rotating Biquadratic Bodies Of Revolution, Mark Nathaniel Callender

Doctoral Dissertations

Prandtl’s lifting line theory expanded the Kutta-Joukowski theorem to calculate the lift and induced drag of finite wings. The circulation distribution about a real wing was represented by a superposition of infinitesimal vortex filaments. From this theory, the optimum distribution of circulation was determined to be elliptical. A consequence of this theory led to the prediction that the elliptical chord distribution on a real fixed wing would provide the elliptical circulation distribution. The author applied the same line of reasoning to lift-producing rotating cylinders in order to determine the cylindrical geometry that would theoretically produce an elliptical circulation distribution. The …

Ecological And Evolutionary Consequences Of Variation In Aristolochic Acids, A Chemical Resource, For Sequestering Specialist Troidini Butterflies, Romina Daniela Dimarco

Doctoral Dissertations

Plant-insect interactions provide an opportunity to examine fundamental ecological and evolutionary processes, including mechanisms of species cooccurrence and adaptations to herbivory and predation. An example is the interaction between butterflies in the Troidini tribe (Papilionidae), a group that sequesters chemical defenses from its host plants in the genus Aristolochia (Aristolochiaceae).

In this dissertation, I examined the ecological and evolutionary consequences of variation in aristolochic acids, the chemical compounds sequestered by Troidini from it host plants, through a combination of observational, experimental and laboratory studies. I conducted studies at several sites throughout the Americas where different levels of knowledge about this …

The Role Of An Intergenerational Acculturation Gap In The Adjustment Of Immigrant Youth: A Meta-Analysis, Min-Jung Jung

Doctoral Dissertations

Rapidly increasing numbers of immigrant families with children in the U.S. have led researchers to study the dynamics of immigrant families, focusing particularly on discrepancies in the acculturation levels of parents and children. Many studies have found such an acculturation gap to be associated with problematic functioning, such as conflicts between family members and poor adjustment outcomes among immigrant youth. Other studies have found no such associations. In order to clarify this association, this dissertation conducted a meta-analysis of available studies. Literature searches identified 63 qualifying studies, in which 117 separate effect sizes were reported.

Concentrating on main effects, the …

Syntheses And Reactions Of Early Transition Metal Amidinate Compounds, Adam Christopher Lamb

Doctoral Dissertations

Homoleptic Groups 4 and 5 metal amide compounds have been used as precursors in CVD/ALD processes to make microelectronic metal oxide thin films. These compounds are often very air sensitive. Ancillary ligands such as amidinates have been used to reduce their air sensitivity and to make their handling easier. Reactions of amidinates with dioxygen and water have thus been used to make metal oxide thin films. Studies of these reactions are important in order to make better precursors and purer thin films. This dissertation focuses on the following areas: (a) Syntheses of zirconium and Group 5 amidinate amides; (b) Studies …

An Examination Of Feedback Request Strategies When Learning A Multi-Dimensional Motor Task Under Self-Controlled And Yoked Conditions, Arya Alami

Doctoral Dissertations

Recent research investigating how learners benefit from having control over some aspect of their practice environment has led to numerous potential explanations for its beneficial effects (Janelle et al., 1997; Chiviacowsky & Wulf, 2002). These explanations, however, are vague and difficult to directly measure. Current research suggests that learners in a self-controlled setting prefer feedback after relatively good performances. More recently, Aiken and colleagues (2012) have provided evidence suggesting that when learners control their feedback schedule while learning a task with multiple dimensions of performance, they prefer and request feedback after both “good” and “poor trials” equally. The purpose of …

Searching For Consensus: Shared Decision Making And Clinical Ethics, Meghan Estell Bungo

Doctoral Dissertations

The focus of this dissertation is the search for consensus in the context of clinical ethics—physician-patient interactions, ethics consultations, and ethics committee meetings focused on a particular patient’s care. I argue that consensus, when achieved through a process of shared deliberation that I outline, is the hallmark of the morally correct decision.

While philosophers have generally denigrated consensus as a guide to morally correct decisions, hospital ethics committees and President’s Councils charged with making recommendations about how to resolve moral conflicts in the clinical setting have clearly valued and aimed at the achievement of consensus. Assuming this search for consensus …

Rural To Urban Intercity Transit User Characteristics Analysis, Demand Estimation And Network Design, Hongtai Yang

Doctoral Dissertations

Rural transit always plays a critical role in transporting rural residents, especially the ones who do not have a car, cannot drive, or choose not to drive. Intercity bus (ICB), deviated fixed route transit (DFRT) and demand responsive transit (DRT) are three major modes of rural public transportation. Although there are more DFRT and DRT service providers and services in the US, due to institutional issues, there are much more studies about ICB than DFRT and DRT. Meanwhile, state governments are struggling on how to improve the rural transit system with limited budget. This dissertation is aimed to fill the …

Supportive Leadership, Employee Engagement And Occupational Safety: A Field Study, Lauren Elizabeth Baxter

Doctoral Dissertations

This archival field study examined the relationships of supportive leadership, employee engagement, and safety outcomes in order to address the current knowledge gap regarding these concepts and also to test predictions of and extend the Job Demands-Job Resources Model. Participants were 3,312 employees from multiple departments located at 11 different locations of a large southeastern utility company. Data were collected on supportive leadership, employee engagement, and safety climate using archival data from self-report questionnaires. Recordable injuries and first-aid instances were collected through the organization’s archival safety records. Three consecutive years of data were included in the study. As expected, supportive …

High Energy Synchrotron X-Ray Study Of Fatigue Damage In Amorphous And Polycrystalline Engineering Alloys, Chih-Pin Chuang

Doctoral Dissertations

The dissertation summarizes a series of studies on the fatigue damage of both amorphous and crystalline engineering alloys. The attention focuses on the utilization of synchrotron x-ray scattering related techniques for advanced material characterizations. In the first part of the research, critical issues regarding the mechanical response and structural evolution of Bulk-Metallic Glasses (BMGs) in the elastic region are addressed. The effects of cyclic-loading on the microstructures of an amorphous alloy are investigated, aiming to provide better mechanistic understandings of fatigue damage in BMGs. The second part of the research focuses on the characterization method based on two-dimensional X-ray diffraction …

Comparing Their Stories: A Narrative Inquiry Of African American Women Of The Student Nonviolent Coordinating Committee (1960-1966) And Contemporary Student Activists (2002-2012), Tracia Nikole Cloud

Doctoral Dissertations

This study is a collection of oral personal experience narratives from four self-identified Black female student activists – two from the Student Nonviolent Coordinating Committee (SNCC) (1960-1966) and two from the contemporary movement (2002-2012). I investigate general aspects of their experiences of being Black, female, students and activists within the context of their communities and educational institutions. My research questions are: 1) What were/are the cultural and historical factors that drove/drive each woman to activism? 2) How did/have women develop(ed) ways of knowing about self and community through activism and education? 3) How do Civil Rights activists (1960-1966) and contemporary …

Adsorption And Diffusion Of Gases In Nano-Porous Materials, Nethika Sahani Suraweera

Doctoral Dissertations

In this work, a systematic computational study directed toward developing a molecular-level understanding of gas adsorption and diffusion characteristics in nano-porous materials is presented. Two different types of porous adsorbents were studied, one crystalline and the other amorphous. Physisorption and diffusion of hydrogen in ten iso-reticular metal-organic frameworks (IRMOFs) were investigated. A set of nine adsorbents taken from a class of novel, amorphous nano-porous materials composed of spherosilicate building blocks and isolated metal sites was also studied, with attention paid to the adsorptive and diffusive behavior of hydrogen, methane, carbon dioxide and their binary mixtures. Both classes of materials were …

Analysis, Segmentation And Prediction Of Knee Cartilage Using Statistical Shape Models, Joseph Michael Johnson

Doctoral Dissertations

Osteoarthritis (OA) of the knee is one of the leading causes of chronic disability (along with the hip). Due to rising healthcare costs associated with OA, it is important to fully understand the disease and how it progresses in the knee. One symptom of knee OA is the degeneration of cartilage in the articulating knee. The cartilage pad plays a major role in painting the biomechanical picture of the knee. This work attempts to quantify the cartilage thickness of healthy male and female knees using statistical shape models (SSMs) for a deep knee bend activity. Additionally, novel cartilage segmentation from …

A Comparison Of Mississippian Period Subadults From The Middle Cumberland And Eastern Regions Of Tennessee To Assess Health And Past Population Interactions, Rebecca Scopa Kelso

Doctoral Dissertations

Human subadult skeletal remains can provide a unique perspective into biosocial aspects of past populations. However, for a variety of reasons, they are often overlooked in the skeletal record. This is especially true for the Mississippian period (ca. 1000 years before present to ca. 400 years before present) populations that inhabited the Middle Cumberland region (MCR) and Eastern Tennessee Region (ETR). Most of the previous studies of these areas focused on adult skeletal remains, leaving out a large and extremely important population segment. To further expand current knowledge on the prehistory of the MCR and ETR, skeletal indicators of disease, …

Understanding Mechanical And Fatigue Behavior Of A Wrought Magnesium Alloy Using In-Situ Neutron And Synchrotron X-Ray Diffraction, Wei Wu

Doctoral Dissertations

Magnesium (Mg) alloys have received great attentions in the past several decades, due to their unique properties of low density, high strength-to-weight ratio, and high specific stiffness. Previous work on fatigue behavior of Mg alloys typically relies on ex situ microstructural characterization and crack-growth monitoring with replica techniques. The primary challenge is thus the lack of an in situ, non-destructive measurement on microstructural length scales, which prevents us from linking the stress analyses (top-down point of view) to the failure mechanisms on inter- and intra-granular scales (bottom-up point of view). A unique opportunity that resolves many of these difficulties …

Virtual Reality Aided Mobile C-Arm Positioning For Image-Guided Surgery, Zhenzhou Shao

Doctoral Dissertations

Image-guided surgery (IGS) is the minimally invasive procedure based on the pre-operative volume in conjunction with intra-operative X-ray images which are commonly captured by mobile C-arms for the confirmation of surgical outcomes. Although currently some commercial navigation systems are employed, one critical issue of such systems is the neglect regarding the radiation exposure to the patient and surgeons. In practice, when one surgical stage is finished, several X-ray images have to be acquired repeatedly by the mobile C-arm to obtain the desired image. Excessive radiation exposure may increase the risk of some complications. Therefore, it is necessary to develop a …

Chemical Vapor Deposition Of Heteroepitaxial Boron Phosphide Thin Films, John Daniel Brasfield

Doctoral Dissertations

Boron monophosphide (BP) is a group III-V compound semiconductor with a wide band gap of 2.3 eV. Its unique electrical properties make it a promising material for use as a room temperature thermal neutron detector and thermoelectric device in high temperature and radiation fields. A thin film of BP enriched in the boron-10 isotope can yield 2.8MeV of energy, which in solid-state BP can yield ∼0.5 million electron-hole pairs that would be detectable with minimal amplification in a device. The high carrier concentration, wide band gap, inertness and refractory nature make it an attractive material for use in the extreme …

Numerical Study Of Hubbard Model For Iron-Based Superconductors, Qinlong Luo

Doctoral Dissertations

This thesis addresses the numerical and analytical study of the iron-based superconductors, mainly using the multi-orbital Hubbard model and Hartree-Fock approximation. The text starts with an introduction to the new iron-based superconductors, followed by a theoretical description of the multi-orbital Hubbard model and Hartree-Fock approximations. The numerical study of the Hubbard model in momentum space is described next, where the phase diagrams for three- and five-orbital Hubbard models are provided. The physically ``realistic" regime of couplings is highlighted, to guide future theoretical work into the proper region of parameters of Hubbard models for iron-based superconductors. What goes next is the …

From Shell To Center: Gaston Bachelard And The Transformation Of Domestic Space In The Nineteenth-Century French Novel, Emily Pace

Doctoral Dissertations

This dissertation will look at the house-occupant relationship in four major French novels of the long nineteenth century: Balzac’s Le Père Goriot (1835), Flaubert’s Madame Bovary (1856), Zola’s Thérèse Raquin (1867), and Proust’s “Combray,” from Du côté de chez Swann (1913). Each of these novels relies heavily on the use and description of interior and domestic space, and the manner in which the characters in each novel inhabit and relate to this space is a reflection of the specific and evolving cultural landscape of the moment when these works were composed, I argue, as well as of the particular obsessions …

Reconstruction Of Patient-Specific Bone Models From X-Ray Radiography, Hatem Amin Abdel Fattah El Dakhakhni

Doctoral Dissertations

The availability of a patient‐specific bone model has become an increasingly invaluable addition to orthopedic case evaluation and planning [1]. Utilized within a wide range of specialized visualization and analysis tools, such models provide unprecedented wealth of bone shape information previously unattainable using traditional radiographic imaging [2]. In this work, a novel bone reconstruction method from two or more x‐ray images is described. This method is superior to previous attempts in terms of accuracy and repeatability. The new technique accurately models the radiological scene in a way that eliminates the need for expensive multi‐planar radiographic imaging systems. It is also …

Development Of Si Device Based Power Converters For High Temperature Operation In Hev Applications, Zhuxian Xu

Doctoral Dissertations

In this dissertation, the feasibility of operating Si devices at 200 ˚C [degree Celsius] is investigated and the guidelines on the development of a high temperature Si converter for operating with 105 ˚C high temperature liquid coolant in hybrid electrical vehicle (HEV) applications are provided.

First, the characterization of a Si IGBT operating at 200 ˚C junction temperatures is presented. It is shown that the commercial 175 ˚C Si IGBT under test can be successfully switched at an elevated junction temperature of 200 ˚C with increased but acceptable losses.

Second, a comprehensive evaluation of Si IGBT ruggedness at high temperature …

A Flute Runs Through It, Sometimes… Understanding Folsom-Era Stone Tool Variation, Robert Detlef Lassen

Doctoral Dissertations

This dissertation addresses the “Folsom-Midland Problem,” in which two distinct varieties of stone projectile points occur together in many Folsom-age sites from the terminal Pleistocene in North America. In order to understand why these point types co-occur, a sample of measurements and photographs of 1,093 artifacts including points, preforms, and ultrathin bifaces has been amassed from 27 archaeological sites and three private collections across the Great Plains region of the United States. Analysis of the Folsom and Midland diagnostic artifacts from the Gault site in Central Texas provides the basis of subsequent analyses of the larger sample and indicates that …