Digital Commons Network^™

Student Perceptions And Persistence : Taking A Person-Centered Approach To Understand Undergraduate Engineering Retention., Brittany Flanery Crawford

Electronic Theses and Dissertations

Many students are leaving their engineering programs as early as the first semester of their undergraduate studies. Although some of the factors related to engineering retention are largely academic, others are tied closely to students’ beliefs or perceptions. Student perceptions data are useful, but often overlooked by researchers who wish to take a person-centered approach to uncover profiles of student beliefs, both adaptive and maladaptive, when it comes to understanding engineering retention. The sample consisted of full-time undergraduate engineering students (N = 834) in the first semester of their undergraduate engineering programs. I used latent transition analysis (LTA) to …

A Two-Stage Approach To Ridesharing Assignment And Auction In A Crowdsourcing Collaborative Transportation Platform., Peiyu Luo

Electronic Theses and Dissertations

Collaborative transportation platforms have emerged as an innovative way for firms and individuals to meet their transportation needs through using services from external profit-seeking drivers. A number of collaborative transportation platforms (such as Uber, Lyft, and MyDHL) arise to facilitate such delivery requests in recent years. A particular collaborative transportation platform usually provides a two sided marketplace with one set of members (service seekers or passengers) posting tasks, and the another set of members (service providers or drivers) accepting on these tasks and providing services. As the collaborative transportation platform attracts more service seekers and providers, the number of open …

An Assessment Of Sustainability In Jefferson County Public Schools (Kentucky)., Elizabeth Ann Ruhe

Electronic Theses and Dissertations

Schools play a vital role in preparing the next generation of citizens to be active, engaged, creative thinkers and problem-solvers. Schools are also large institutions in their communities, employing many people and spending large sums of money. What happens in schools has an impact on their surrounding communities. Human behaviors are having a significant impact on our planet and changes in our society are affecting the sense of safety and security of our citizens. These are aspects of sustainability that schools need to begin addressing. This research looks at sustainability practices in a large urban school district to document current …

Segmentation And Classification Of Lung Nodules From Thoracic Ct Scans : Methods Based On Dictionary Learning And Deep Convolutional Neural Networks., Mohammad Mehdi Farhangi

Electronic Theses and Dissertations

Lung cancer is a leading cause of cancer death in the world. Key to survival of patients is early diagnosis. Studies have demonstrated that screening high risk patients with Low-dose Computed Tomography (CT) is invaluable for reducing morbidity and mortality. Computer Aided Diagnosis (CADx) systems can assist radiologists and care providers in reading and analyzing lung CT images to segment, classify, and keep track of nodules for signs of cancer. In this thesis, we propose a CADx system for this purpose. To predict lung nodule malignancy, we propose a new deep learning framework that combines Convolutional Neural Networks (CNN) and …

Technology For The 21st Century Workforce: A Case Study Of A Rural East Tennessee Workforce Community, Kim Bolton

Electronic Theses and Dissertations

The purpose of this study was to assess technology use, on-the-job technology training, education levels, and salary ranges of employees in low-, middle-, and high- skill jobs in a rural county in East Tennessee to create an example of a small town workforce. For this study, technology included computers, robotics, and mobile technology. A survey determined the technology used, training provided, salaries, and job skill levels based on education obtained and required by major employers. The study identified the level of jobs requiring more technology skills and salaries or training related to these job skill levels. Participants included 336 persons …

Development Of Granulated Adsorbent For Clean-Up Of Water Contaminated By Cesium, Esther Alorkpa

Electronic Theses and Dissertations

A study was conducted on sol-gel synthesis of an adsorbent (phosphotungstic acid embedded in silica gel, H-PTA/SiO­₂) of radioactive cesium. A novelty of this work is covalent bonding of PTA to the surface of solid support that prevents leaching from the surface of the material. The sample was granulated with a binder, aluminium oxide (γ-Al₂O₃). Solid-state NMR and FT-IR spectroscopy were used to confirm the presence of Keggin units of PTA in the bound materials. Thermal analysis of H-PTA/SiO­₂ - γ-Al₂O₃ (50 %) showed that the water content in the …

Pocket Ace: Neglect Of Child Sexual Abuse Survivors In The Aces Study Questionnaire, Robyn Dolson

Electronic Theses and Dissertations

In 1998, a seminal study on adverse childhood experiences (ACEs) and subsequent health risks catapulted ACEs and the study questionnaire into the zeitgeist. However, its childhood sexual abuse (CSA) item is problematic as it requires the perpetrator have been 5-years or older than the victim. To assess whether some survivors’ CSA is not identified by the current item, whether their exclusion prevents access to services requiring a four-threshold ACE score, and how their health outcomes compared to other CSA groups and controls, an international sample of 974 women completed an online survey assessing their current health and CSA history using …

Seeing The World Differently. An Exploration Of A Professional Development Model Bridging Science And Lay Cultures, Michael D. Garrett

Electronic Theses and Dissertations

This study explores the rationale, efficacy, and social validity of a professional development model designed to move elementary school science activities closer to the practices of working scientists as required by the United States’ “Next Generation Science Standards.” The model is culturally sensitive and aims to create experiences with high subjective task value. The formal theory of change uses scaffolding, Piagetian agency, and Vygotskian learning opportunities to argue that culturally familiar representational tasks in culturally natural intersubjective contexts can lead to work prototypical of scientific modeling under particular facilitation conditions: when participants (a) are allowed free use of their cognitive …

Successful Factors For Native And Community College Transfer Students In Engineering Technology At A Four-Year University, Leendert Craig

Electronic Theses and Dissertations

Students who attend community colleges often transfer to 4-year universities seeking to earn a degree typically not offered at the community college level. Tennessee has 2 programs: the Tennessee Promise and the Tennessee Reconnect programs that offer students tuition-free access to the state’s community college system. Previous studies have been conducted to compare transfer students’ performances to that of native students and typically compared the students in all disciplines. This study seeks to compare transfer students (students who enter the participating university with 40 or more credit hours) to native students (students who initially enrolled or transferred into the 4-year …

Teacher Factors And Student Achievement As Measured By The Act Assessment And Subsequent Teacher Perceptions Of Those Factors, Jessica Weaver

Electronic Theses and Dissertations

The purpose of this quantitative study was to investigate educator factors that have an impact on student achievement and overall school performance as indicated in the American College Test (ACT) scores from the district and the individual schools. Educators from a moderate-sized public school district participated in an anonymous online survey. According to the Tennessee Department of Education (TDOE) Report Card, the district ACT composite is a 20.1 (TDOE, 2018e). Two of the district’s schools’ results are higher than the district composite, while the other five are consistent with or below the district composite. Participants of this study shared their …

Tennessee High School Counselors' And Dual Enrollment Advisors' Perceptions Of Student Readiness For Dual Enrollment, Aleeta L. Shaw

Electronic Theses and Dissertations

The purpose of this qualitative phenomenological study was to explore Tennessee high school counselors’ and dual enrollment advisors’ perceptions of student readiness for dual enrollment within the context of school, institutional, state, and federal policies as aligned with adolescent development theories in order to inform both policy and practice. Twelve purposely sampled participants from three school districts within the First Tennessee Core Region responded to questions via a recorded phone interview. Participants reflected on the readiness of their students for dual enrollment in the academic, social, and emotional domains. Additionally, participants identified strengths and weaknesses of dual enrollment programs and …

Comparison Of Imputation Methods For Mixed Data Missing At Random, Kaitlyn Heidt

Electronic Theses and Dissertations

A statistician's job is to produce statistical models. When these models are precise and unbiased, we can relate them to new data appropriately. However, when data sets have missing values, assumptions to statistical methods are violated and produce biased results. The statistician's objective is to implement methods that produce unbiased and accurate results. Research in missing data is becoming popular as modern methods that produce unbiased and accurate results are emerging, such as MICE in R, a statistical software. Using real data, we compare four common imputation methods, in the MICE package in R, at different levels of missingness. The …

Ecometric Estimation Of Present And Past Climate Of North America Using Crown Heights Of Rodents And Lagomorphs: With Application To The Middle Miocene Climatic Optimum, Julia Schap

Electronic Theses and Dissertations

Continental scale studies on ungulate crown heights in relation to climate and habitat changes have revealed a correlation between increasing hypsodonty and a shift to more arid environments. Small mammals have been shown to adapt to changing habitats millions of years earlier than larger mammals. In this study I examined fossil localities throughout the last 37 Ma across North America. Diversity of rodents and lagomorphs were analyzed through this time period, with examination of community structure characterized by relative percentages of taxa with different crown heights. Overall, a decrease in precipitation and temperature was found across North America from 37 …

Perfect Double Roman Domination Of Trees, Ayotunde Egunjobi

Electronic Theses and Dissertations

See supplemental content for abstract

Synthesis And Evaluation Of 1,2,4-Oxadiazolidinones: The Search For A Potential Non-Β-Lactam Β-Lactamase Inhibitors., Chimdi Eke Kalu

Electronic Theses and Dissertations

β-lactam antibiotics have been the most widely used drug of choice to combat infectious disease caused by bacteria. Unfortunately, their effectiveness is drastically threatened by bacterial β-lactamases. β-lactamases is responsible for the resistance to most antibiotic drugs. For decades, β-lactam β-lactamases inhibitors have been used to reduce bacterial resistance; however, in this study 1,2,4-oxadiazolidinone derivatives as a non-β-lactam β-lactamases inhibitor against TEM-1 and P99 β-lactamases. The significance of oxadiazolidinone is the prominent five-membered ring scaffold in its structure, which is configurationally stable and present in other biologically active compounds such as linezolid and avibactam. Oxadiazolidinones were synthesized by treating nitrones …

A Systematic Assessment Of Socio-Economic Impacts Of Prolonged Episodic Volcano Crises, Justin Peers

Electronic Theses and Dissertations

Uncertainty surrounding volcanic activity can lead to socio-economic crises with or without an eruption as demonstrated by the post-1978 response to unrest of Long Valley Caldera (LVC), CA. Extensive research in physical sciences provides a foundation on which to assess direct impacts of hazards, but fewer resources have been dedicated towards understanding human responses to volcanic risk. To evaluate natural hazard risk issues at LVC, a multi-hazard, mail-based, household survey was conducted to compare perceptions of volcanic, seismic, and wildfire hazards. Impacts of volcanic activity on housing prices and businesses were examined at the county-level for three volcanoes with a …

The Correlation Between The Act, Inc. Explore Test And Student Success In High School Advanced And Advanced Placement Mathematics Courses, Virginia Story

Electronic Theses and Dissertations

The purpose of this study was to compare the relationship between the mathematics portion of the EXPLORE test with students successes in advanced and Advanced Placement(AP) mathematics courses in high school. The data was collected from a rural Tennessee school system consisting of five years of data among graduated seniors. Analysis was completed to determine the difference between the two county high schools in advanced coursework. The findings of this study concluded a positive correlation between EXPLORE scores and the frequency of students who took advanced mathematics courses. Positive correlation between EXPLORE scores and student successes in advanced courses was …

Paleoecology And Land-Use Of Quaternary Megafauna From Saltville, Virginia, Emily Simpson

Electronic Theses and Dissertations

Land-use, feeding habits, and response to seasonality by Quaternary megaherbivores in Saltville, Virginia, is poorly understood. Stable isotope analyses of serially sampled Bootherium and Equus enamel from Saltville were used to explore seasonally calibrated (δ¹⁸O) patterns in megaherbivore diet (δ¹³C) and land-use (⁸⁷Sr/⁸⁶Sr). Overall, this dataset suggests an open forest with relatively constant temperatures year round that were similar to modern conditions. Neither Bootherium or Equus individuals spent a significant amount of time at higher elevations in the nearby Blue Ridge geologic province. These analyses provide a unique perspective on long-term response …

Taking Notes: Generating Twelve-Tone Music With Mathematics, Nathan Molder

Electronic Theses and Dissertations

There has often been a connection between music and mathematics. The world of musical composition is full of combinations of orderings of different musical notes, each of which has different sound quality, length, and em phasis. One of the more intricate composition styles is twelve-tone music, where twelve unique notes (up to octave isomorphism) must be used before they can be repeated. In this thesis, we aim to show multiple ways in which mathematics can be used directly to compose twelve-tone musical scores.

Culturally Responsive Training For Secondary English Language Teachers, Tina Mccorkle

Electronic Theses and Dissertations

In this quantitative study, I investigated the effectiveness of a training intervention program to positively impact secondary teacher attitudes and perceptions of culturally responsive teaching (CRT). The study is relevant in Alvin Independent School District given the demographic shift resulting in an increase in Hispanic students and students learning English as a second language. The purpose of the study was to investigate teacher attitudes and perceptions of CRT to determine if there was a statistically significant difference according to pre- and post-survey data in order to evaluate the effectiveness of the CRT program intervention. The CRT research from Ladson-Billings (1992) …

Experimental Investigation Of The Manufacture Of Tunable Graphene Oxide Filter Membranes Using Intense Pulse Light, Joshua H Kotter

Electronic Theses and Dissertations

Reduced graphene oxide is a thin, strong, and inexpensive material with a channel and pore structure that make it a promising candidate for a filtration material. Reduced graphene oxide has been produced and tested in the laboratory, but a lack of scalable manufacturing techniques have limited its commercial use.

This thesis has shown that graphene oxide can be rapidly manufactured with an industrially scalable flash reduction process. The flash reduction process uses 0.58 millisecond pulses from a xenon lamp to reduce the graphene oxide film in less than a minute. Results for partially reduced graphene oxide membranes tuned by the …

The Relativistic Harmonic Oscillator And The Generalization Of Lewis' Invariant, Daniel Reinhart

Electronic Theses and Dissertations

In this thesis, we determine an asymptotic solution for the one dimensional relativistic harmonic oscillator using multiple scale analysis and relate the resulting invariant to Lewis' invariant. We then generalize the equations leading to Lewis' invariant so they are relativistically correct. Next we attempt to find an asymptotic solution for the general equations by making simplifying assumptions on the parameter characterizing the adiabatic nature of the system. The first term in the series for Lewis' invariant corresponds to the adiabatic invariant for systems whose frequency varies slowly. For the relativistic case we find a new conserved quantity and seek to …

Cognitive And Vascular Risk Factors For Depression: Testing An Integrated Theoretical Framework, Rosanna Scott

Electronic Theses and Dissertations

Objective: Theoretical models that have guided the study of later-life depression include the vascular depression hypothesis, depression-executive dysfunction syndrome, and the CaR-FA-X model. Evidence suggests these can be integrated into a single developmental model of disordered mood (and its associated overgeneral memory feature) in later-life to delineate a mechanism of the vascular depression effect and identify modifiable intervention targets. Methods: In older adults, four serial mediation models evaluated the relationships between (1) vascular burden and depressive symptoms via executive control and rumination, and (2) vascular burden and autobiographical memory specificity (AMS) via executive control and rumination. In younger adults, four …

Development Of 3d Printed And 3d Metal-Based Micro/Nanofabricated, And Nano-Functionalized, Microelectrode Array (Mea) Biosensors For Flexible, Conformable, And In Vitro Applications, Charles Didier

Electronic Theses and Dissertations

Emerging fields such as "Organs on a Chip", disease modeling in vitro, stem cell manufacturing and wearable bioelectronics are demanding rapid development of 3D Microelectrode Arrays (MEAs) for electrical interfacing with biological constructs. The work reported in this thesis focuses on two developmental tracks: "Dynamic 3D MEAs" and metal microfabrication for 3D MEAs. In the first part of the thesis, we explore the capabilities and limitations of 3D printed microserpentines (µserpentines) and utilize these structures to develop dynamic 3D microelectrodes. Analytical modeling of µserpentines flexibility followed by integration into a flexible Kapton® package and PDMS insulation are demonstrated. These 3D …

Applications Of Geometric And Spectral Methods In Graph Theory, Lauren Morey Nelsen

Electronic Theses and Dissertations

Networks, or graphs, are useful for studying many things in today’s world. Graphs can be used to represent connections on social media, transportation networks, or even the internet. Because of this, it’s helpful to study graphs and learn what we can say about the structure of a given graph or what properties it might have. This dissertation focuses on the use of the probabilistic method and spectral graph theory to understand the geometric structure of graphs and find structures in graphs. We will also discuss graph curvature and how curvature lower bounds can be used to give us information about …

Supervised Machine Learning Techniques For Short-Term Load Forecasting, Harish Amarasundar

Electronic Theses and Dissertations

Electric Load Forecasting is essential for the utility companies for energy management based on the demand. Machine Learning Algorithms has been in the forefront for prediction algorithms. This Thesis is mainly aimed to provide utility companies with a better insight about the wide range of Techniques available to forecast the load demands based on different scenarios. Supervised Machine Learning Algorithms were used to come up with the best possible solution for Short-Term Electric Load forecasting. The input Data set has the hourly load values, Weather data set and other details of a Day. The models were evaluated using MAPE and …

Control Strategy For A Small-Scale Microgrid Based On Battery Energy Storage System-Virtual Synchronous Generator (Bess-Vsg), Wei Gao

Electronic Theses and Dissertations

As one of widely deployed renewable energy resources, PV power is playing a very important role in microgrids today. It has advantages such as making the best of natural solar energy and being friendly to our environment. In this thesis, solar PV based microgrid is studied using modeling and simulation. Microgrid can run in either grid-connected-mode or islanded-mode. However, there are also some disadvantages for solar power. For solar panel, its output is influenced by weather conditions such as illumination intensity and temperature. In addition, during the control process of grid-connected mode, it is hard to guarantee its output power …

Divergence Of Threespine Stickleback That Differ In Nuptial Coloration, Clara Sophie Jenck

Electronic Theses and Dissertations

Recent research has led to a much better understanding of the evolutionary processes that mold and structure variation within and among populations. How populations diverge at the genome-wide level and how polymorphism is maintained within a species, however, remains unclear. We address these questions with two freshwater color morphs, red and black, of the threespine stickleback fish (Gasterosteus aculeatus) from the northwest United States, in which a shift from red to black nuptial coloration occurred in several locations following glacial retreat. We measured phenotypic variation in a suite of traits and used next generation sequencing to characterize within-species and among-morph …

Contrasting Chicago School And Kaleckian Theories: Industrial Organization, Income Distribution, And Historical Policy Significance In The United States, Henry Aaron Dobbs

Electronic Theses and Dissertations

The purpose of this paper is to identify the role that long-run industry concentration plays in determining the distribution of income, particularly in the past four decades in the United States, as well as examining how industry concentration has developed during that period. The paper is especially focused on the fall in labor’s share of income. First, I examine current literature regarding trends in industry concentration and its relation to the distribution of income. Next, I examine the historical impact of the Chicago School of Economics on this subject, focusing on the school of thought’s propositions regarding industry concentration, their …

Amelioration Of Alzheimer's Disease Pathology In 12-Month-Old Happ(Sweind) Transgenic Mice After Treatment With A Cysteine Rich Whey Supplement, Immunocal®, Srivalli Puttagunta

Electronic Theses and Dissertations

Deficits in Reelin expression and signaling play a pathogenic role in Alzheimer’s disease (AD). Thus, strategies aimed at correcting Reelin deficits may provide a novel therapeutic approach to treating AD. The cysteine-rich, whey protein supplement, Immunocal®, has recently been shown to rescue Reelin expression in a mouse model of Schizophrenia. Given that Reelin-expressing neurons of the entorhinal cortex region are a highly vulnerable population of cells that are lost early in AD, we examined the effects of Immunocal® in the hippocampal-entorhinal cortex formation in a mouse model of AD. Glutathione levels and Reelin expression in the hippocampal-entorhinal cortex formation (entorhinal …