Digital Commons Network^™

Manipulating Light Quality, Light Intensity, And Carbon Dioxide Concentration To Optimize Indoor And Greenhouse Production Of Annual Bedding Plant Seedlings, Joshua Ken Craver

Open Access Dissertations

Annual bedding plant seedlings (plugs) are commonly produced in northern latitudes during the late winter and early spring when the natural daily light integral (DLI) in greenhouses is below recommended levels. Greenhouse supplemental lighting (SL) provides a means of increasing the DLI, with high-pressure sodium (HPS) lamps representing the current industry standard. However, low-profile and high-intensity light-emitting diode (LED) fixtures have recently emerged as a possible alternative for greenhouse SL. Additionally, due to the emission of very little radiant heat, LEDs may be used for sole-source lighting (SSL) applications where plants are produced on vertical shelving units in warehouses or …

Improving Information Alignment And Distributed Coordination For Secure Information Supply Chains, Omar Eldardiry

Open Access Dissertations

Industries are constantly striving to incorporate the latest technology systems into their operations so that they can maintain a competitive edge in their respective markets. However, even when they are able to stay up to speed with technological advancement, there continues to be a gap between the workforce skill set and available technologies. Organizations may acquire advanced systems, yet end up spending extended periods of time in the implementation and deployment phases, resulting in lost resources and productivity. The primary focus of this research is on streamlining the implementation and integration of new information technology systems to avoid the dire …

Design Methodology For A High-Frequency Transformer In An Isolating Dc-Dc Converter, Veda Samhitha Duppalli

Open Access Dissertations

The objective of this work is to propose a design methodology for a high-frequency transformer in the context of an isolating DC-DC converter. The design challenges relating to high-frequency operation include transformer parasitics, high-frequency loss mechanisms, and their coupled effect on the performance of the transformer and DC-DC converter. These issues are addressed in this work by incorporating high-frequency effects into the relevant magnetic, electrical, and thermal analyses needed for multi-objective optimization based design.

First, an accurate and computationally-efficient method for the transformer magnetic analysis is proposed. Leakage inductance is calculated using a procedure based on the Biot-Savart law and …

Eudaimonia And The Best Life: Epicurus' Objective Goods Perfectionism, Alex R. Gillham

Open Access Dissertations

In this dissertation, I argue that there is a standard reading of Epicurus’ ethics (SRE). The thesis of SRE is that Epicurus is both a hedonist and monist about the good, which entails that if something is good, then it (a) is pleasure, (b) contributes to pleasure, or (c) constitutes pleasure. If something is good in the sense of (a), it is intrinsically good. If something is good in the sense of (b), it is instrumentally good, i.e., it is good insofar as it is a tool for securing pleasure. If something is good in the sense of (c), it …

Conceptualizing Individual Disaster Resilience: Benchmarking Tools For Individual And Social Coping Capacity For A Disaster Resilient Society, Lindsey J. Ditirro

Open Access Dissertations

Individual disaster resilience is a new and understudied concept. It is defined as the degree to which an individual has the capacity to obtain, process, and understand disaster-related information and identify and mobilize relevant resources to make appropriate decisions and actions in dealing with disaster-related risk situations. This concept is composed of four factors: knowledge coping, information coping, communal coping and affective coping. This dissertation operationalizes this new concept and its four dimensions and develops a measurement system to test this multivariate concept known as the Individual Disaster Resilience Assessment or InDRA. This was accomplished by conducting two studies. Forty-six …

Efficient Markov Chain Monte Carlo Methods, Youhan Fang

Open Access Dissertations

Generating random samples from a prescribed distribution is one of the most important and challenging problems in machine learning, Bayesian statistics, and the simulation of materials. Markov Chain Monte Carlo (MCMC) methods are usually the required tool for this task, if the desired distribution is known only up to a multiplicative constant. Samples produced by an MCMC method are real values in N-dimensional space, called the configuration space. The distribution of such samples converges to the target distribution in the limit. However, existing MCMC methods still face many challenges that are not well resolved. Difficulties for sampling by using MCMC …

Predicting Graduation And College Gpa: A Multilevel Analysis Investigating The Contextual Effect Of College Major, John A. Gipson

Open Access Dissertations

Despite the overwhelming evidence that higher education data are nested at various levels, single-level techniques such as regression and analysis of variance are commonly used to investigate student outcomes. This is problematic as a mismatch in methodology and research questions can lead to biased parameter estimates. The purpose of this study was to predict cumulative grade point average (GPA) and the likelihood of four-year and six-year graduation while simultaneously accounting for select pre-college characteristics, during-college experiences, and the interrelationship between student-level and major-level predictors. To achieve the desired outcomes, the study applied multilevel modeling techniques to secondary data for new …

Political Order In The Modernizing Mormon Kingdom, 1887-1896, Mark Denninghoff

Open Access Dissertations

What was the function of political parties in colonizing the American West? How did the arrival of national party politics impact the public lives and lived religious experience of everyday Mormons? How did the Latter-day Saints disaggregate their hierarchal religious communities and re-aggregate them into party affiliations that pitted co-religionists against one another? Mormons had endured coerced adoption of secular public education, industrialization, a hostile military presence and legal battles threatening the existence of the church. The introduction of national political parties served as tipping point that precipitated the integration of this religiously constituted community into the American polity at …

Food Quality Versus Quantity: Consumer's Value Perception And The Influence Of Eating Style, Li Ge

Open Access Dissertations

Increased portion size of commonly consumed foods has been considered a strong environmental factor contributing to food overconsumption. Regulatory interventions to reduce portion sizes in restaurants, however, are likely to be opposed by the foodservice industry due to concerns that reduced portions may negatively affect consumers’ value perception. These interventions may also be considered as paternalistic by some consumers. Three studies were conducted to examine possible approaches to the “portion inflation” problem from different perspectives, with the intention to seek balance between public health benefits and business interests, and between corporate responsibility and consumer responsibility.

In study one, two quasi-experiments …

Highly Excited States Of Small Molecules And Negative Atomic Ions, Matthew T. Eiles

Open Access Dissertations

Excited states of atoms and molecules exhibit a rich array of diverse phenomena. This dissertation examines two exotic states of atoms at such excited levels: Rydberg molecules and atomic negative ions. Rydberg molecules are formed by a Rydberg atom and one or more ground state atoms, and can be highly polar due to their unusual electronic wave functions and enormous bond lengths. This dissertation expands the theory of these molecules by studying the formation and structure of polyatomic molecules, multichannel Rydberg molecules formed from divalent atoms, and spin effects and relativistic interactions. It also details intermolecular forces between Rydberg molecules, …

Influence Of Radical Proximity On The Charge Transport Of Nitroxide-Based Electronics, Martha E. Hay

Open Access Dissertations

As the societal dependence upon electronics continues to expand, consumer demand dictates the development of new materials to further augment both performance and user experience. Organic electronic materials enable unique features and applications due to the synthetic tunability of their optoelectronic properties, light weight, compatibility with flexible substrates, and biocompatibility. Radical polymers, macromolecules bearing pendant stable radical sites, have emerged as a new class of conducting polymers. These materials have demonstrated charge storage and transport capabilities in electrolyte-supported systems (e.g., secondary batteries) and have since been a source of inquiry for solid-state applications. Initial studies of their solid-state properties have …

The Design And Analysis Of Calcium-41 Clinical Trials To Study Treatments For Bone Loss, Courtney N. Henry

Open Access Dissertations

Calcium-41 (41Ca) is a biological tracer used to rapidly and sensitively monitor skeletal calcium metabolism. Measurements of the 41Ca:Ca ratio in urine quantify changes in net bone turnover (i.e. differences in bone formation and resorption). A biomedical application of 41Ca technology clinically assesses the efficacy of treatments for preventing bone loss, primarily targeting susceptible populations such as post-menopausal women.

This research initially describes a 41Ca simulation study to determine efficient 41Ca experimental designs that preserve the accuracy and reliability of estimation and the statistical power of our conventional design, whilst substantially lowering costs by reducing the number of samples and/or …

Nooses & Balancing Acts: Reflections And Advice On Racism And Antiracism From Black Writing Tutors At Predominantly White Institutions, Talisha Haltiwanger Morrison

Open Access Dissertations

Over the past 10-15 years, writing center scholars have acknowledged the significance of race to writing center work and examined the ways racism manifests within writing center spaces and practices. More recently, conversations have shifted from acknowledging racism to how to combat it through antiracist activism. However, due to the demographics of the field, the voices most often contributing to these conversations are white scholars, many of them directors at predominantly white institutions (PWIs). This study positions Black writing tutors as individuals with expertise to share on how to engage in antiracism through writing center work that stems from their …

Memory Subsystems For Security, Consistency, And Scalability, Terry Ching-Hsiang Hsu

Open Access Dissertations

In response to the continuous demand for the ability to process ever larger datasets, as well as discoveries in next-generation memory technologies, researchers have been vigorously studying memory-driven computing architectures that shall allow data-intensive applications to access enormous amounts of pooled non-volatile memory. As applications continue to interact with increasing amounts of components and datasets, existing systems struggle to eÿciently enforce the principle of least privilege for security. While non-volatile memory can retain data even after a power loss and allow for large main memory capacity, programmers have to bear the burdens of maintaining the consistency of program memory for …

The Federal Reserve As A Social Actor: On The Intersection Of Communication And Investor Expectations, Lauren Berkshire Hearit

Open Access Dissertations

As the U.S. central bank, the Federal Reserve sets U.S. monetary policy (i.e., control of the money supply and management of the inflation rate, economic growth, and price stability) through the Federal Open Market Committee (FOMC) and serves as a lender of last resort. A major actor in the U.S. economic system, it is dispersed geographically across the United States and contains many branches. The chairman of the Federal Reserve communicates on behalf of the entire system before Congress, makes a statement after FOMC meetings, and gives speeches and lectures on economic status and related economic topics.

Yet there is …

Effects Of Within-Day Dietary Protein Distribution On Changes In Plasma Amino Acid Concentrations And Body Composition, Joshua L. Hudson

Open Access Dissertations

The increasing prevalence of adults with overweight and obesity in the United States emphasizes the need for research on novel behavioral and lifestyle interventions such as dietary manipulation to modulate the epidemic. While consuming an energy-restricted diet is a proven method of reducing adiposity, adhering to and adopting a diet that is not self-chosen is difficult. Not unimportantly, reducing energy intake also typically results in a reduction in skeletal muscle mass. Skeletal muscle is important for facilitating functional movements, metabolizing glucose, and contributing to resting energy expenditure. Multitudinous research has focused on the macronutrient composition of an energy-restricted diet both …

Model And Appearance Based Analysis Of Neuronal Morphology From Different Microscopy Imaging Modalities, Sarun Gulyanon

Open Access Dissertations

The neuronal morphology analysis is key for understanding how a brain works. This process requires the neuron imaging system with single-cell resolution; however, there is no feasible system for the human brain. Fortunately, the knowledge can be inferred from the model organism, Drosophila melanogaster, to the human system. This dissertation explores the morphology analysis of Drosophila larvae at single-cell resolution in static images and image sequences, as well as multiple microscopy imaging modalities. Our contributions are on both computational methods for morphology quantification and analysis of the influence of the anatomical aspect. We develop novel model-and-appearance-based methods for morphology quantification …

Automated Fault Detection, Diagnostics, Impact Evaluation, And Service Decision-Making For Direct Expansion Air Conditioners, Andrew L. Hjortland

Open Access Dissertations

This work describes approaches for automatically detecting, diagnosis, and evaluating the impacts of common faults in unitary rooftop air conditioning equipment. A semi-empirical component-based modeling approach using virtual sensors has been implemented using low-cost microcontrollers and tested on fixed-speed and variable-speed equipment using laboratory psychrometric test chambers. A previously developed virtual refrigerant charge sensor was applied to a fixed-speed rooftop unit with combinations of condenser types and expansion valve types and resulted in average prediction errors less than 10%. In addition, a methodology was developed that can be used to tune the empirical parameters of the model using data collected …

How Heat Affects Human Hair: Thermal Characterization And Predictive Modeling Of Flat Ironing Effects, Jaesik Hahn

Open Access Dissertations

Many people with curly hair experience heat damage – loss of curls and structural degradation of hair – after repetitive use of flat irons. While an array of relevant studies provide insight into thermochemical processes behind the phenomenon, practical tools for flat iron users are unavailable. As a result, people shun heat for fear of unpredictable amount of heat damage while adopting other laborious methods to satisfy a persevering need for temporary hair straightening. Thus three overarching research projects emerge to address the problem. In Part 1, I develop an empirical approach to mathematically correlate four flat ironing parameters (a …

Essays On The Economics Of Education, Kendall J. Kennedy

Open Access Dissertations

This dissertation is composed of three independent chapters in the field of the economics of education. The first chapter studies the impact of grade retention on a broad group of conventional estimation strategies in the economics literature. The second chapter studies the effects of a widespread negative incentive policy on educational choice. The third chapter studies the effects of the same policy on teen behavioral and health outcomes. The first chapter investigates how the high prevalence of grade retention in the United States causes bias in a wide variety of conventional estimation strategies. Over the past four decades, ninth grade …

Investigating The Developmental Toxicity Of Legacy, Emergent, And Current Use Environmental Toxicants Using The Zebrafish Model System, Katharine Ann Marie Horzmann

Open Access Dissertations

Environmental toxicants are chemical or physical agents that enter the environment and can have adverse health effects on populations of humans. Chemical contamination of rivers, lakes, and ground water is a significant public health concern; 23% of private wells are contaminated with at least one significant environmental toxicant and chemical spill incidences can have severe consequences to human health and the environment. Even low doses of chemicals in the environment can have an effect on human health, and it is suggested by the Developmental Origins of Health and Disease (DOHaD) hypothesis that embryonic exposure to toxicants alters health status and …

Techniques For Reconstructing A Riemannian Metric Via The Boundary Control Method, Paul A. Kepley

Open Access Dissertations

In this dissertation, we consider some new techniques related to the solution of the inverse boundary value problem for the wave equation with partial boundary data. Most results are formulated in a geometric setting, where waves propagate in the interior of a smooth manifold with smooth boundary M, and the wave speed is modelled by an unknown Riemannian metric g. For data, we focus mostly on using the Neumann-to-Dirichlet (N-to-D) map with sources and receivers restricted to a measurement set Γ ⊂ ∂M. The goal of the inverse problem, in this setting, is to use these wave boundary measurements to …

Ultra Purification Of Gallium By Zone Refining, Daniel Kim

Open Access Dissertations

High electron mobility is essential to improve two-dimensional electron gas (2DEG) quality in MBE grown AlGaAs/GaAs heterostructures. Recently, gallium purity was identified as limit to electron mobility in such structures. A laboratory horizontal zone refiner was constructed and procedures such as cleaning operation and handling/extracting samples were developed to suit needs for producing ultra-high purity gallium. One major problem is that most of the impurities are already below detection limit of current measurement techniques for starting high purity gallium. The 8N gallium (99.999999%, 10 ppb nominal purity) is the most pure commercially available gallium and measuring the purity becomes difficult …

Large Scale Constrained Trajectory Optimization Using Indirect Methods, Thomas Antony

Open Access Dissertations

State-of-the-art direct and indirect methods face significant challenges when solving large scale constrained trajectory optimization problems. Two main challenges when using indirect methods to solve such problems are difficulties in handling path inequality constraints, and the exponential increase in computation time as the number of states and constraints in problem increases. The latter challenge affects both direct and indirect methods. A methodology called the Integrated Control Regularization Method (ICRM) is developed for incorporating path constraints into optimal control problems when using indirect methods. ICRM removes the need for multiple constrained and unconstrained arcs and converts constrained optimal control problems into …

Analysis And Automated Discovery Of Attacks In Transport Protocols, Samuel C. Jero

Open Access Dissertations

Transport protocols like TCP and QUIC are a crucial component of today’s Internet, underlying services as diverse as email, file transfer, web browsing, video conferencing, and instant messaging as well as infrastructure protocols like BGP and secure network protocols like TLS. Transport protocols provide a variety of important guarantees like reliability, in-order delivery, and congestion control to applications. As a result, the design and implementation of transport protocols is complex, with many components, special cases, interacting features, and efficiency considerations, leading to a high probability of bugs. Unfortunately, today the testing of transport protocols is mainly a manual, ad-hoc process. …

Evaluation Of Reactivity Feedbacks Due To Core Deformation In Fast Reactors, Tian Jing

Open Access Dissertations

In order to meet the worldwide demands on sustainable energy, new generation of nuclear reactor systems has been proposed to continue the benefit of nuclear power for electricity production. Sodium-cooled fast reactor (SFR) is one of the most promising candidate among those reactor concepts for both energy production and minimizing radioactive nuclear waste and features inherent safety potential. To ensure inherent safety characteristics of SFR, accurate evaluation of reactivity feedbacks is essential. However, accurate evaluation of the negative reactivity induced by the core radial expansion and assembly bowing remains challenging. SFR has a relatively large coolant temperature rise, and thus …

Three Essays On Strategic Human Capital, Managers And Competitive Advantage, Jongsoo Kim

Open Access Dissertations

In this dissertation, I investigate the interplay between strategic human capital and the role of managers in an organization. In Essay 1, using a natural experiment setting with a dataset on change of interdependence that an organization requires, and unexpected employee exit in a professional sports league for the period 1992 to 2010, I examine the consequence of losing strategically important human resources (HR) and shows that how specific organizational recovering techniques for dealing with HR can help the firm’s strategic renewal process. The data present that the consequential impact of losing employees is depending upon the type of interdependence …

Motion Paradigm To Detect Pedestrians And Vehicle Collision, Mehmet Kilicarslan

Open Access Dissertations

Nowadays, many vehicles are equipped with a vehicle borne camera system for monitoring drivers’ behavior, accident investigation, road environment assessment, and vehicle safety design. This produces a huge amount of video data recorded daily. Analyzing and interpreting these data in an efficient way has become a non-trivial task. Therefore, in this work, for efficient analysis of these data, videos are mapped into a temporal profile image of reduced dimension for acquiring motion information. The video profile is compact and continues motion representation of a video. This work examines those motion profile trajectories. A new motion based collision avoidance and pedestrian …

Welfare Impcats Of Optimal Virtual Bidding In A Multi-Settlement Electricity Market With Transmission Line Congestion, Hyungkwan Kim

Open Access Dissertations

With a goal of improving the performance of wholesale electricity markets, virtual financial products have been introduced. Virtual bids are purely financial instruments that may be used to speculate on the differences between prices in the forward and spot markets in a two-settlement electricity market. While there is evidence that price convergence across these markets can be induced by virtual bidding, other research has shown that the impacts on the welfare of market participants are less clear. The problem is that, while virtual bidding may narrow the price gap, if it does so by inflating the prices, then electricity consumers …

The Effects Of A Career Development Intervention On The Career Aspirations Of Middle School Students, William E. Kovach

Open Access Dissertations

The purpose of the study was to identify and evaluate the effectiveness of a career development program at the middle school level. The intent was to provide middle school students with the necessary formalized support to assist them to develop self-awareness and self-efficacy, understand why they are in school, connect long-term goals with the steps needed to achieve those goals, and receive support from the teacher/advisor, counselors, and business community throughout the process. Further, through the tenets of Social Cognitive Career Theory and values-affirmation intervention, the purpose was to implement an introspective opportunity for students to reflect on their career …