Digital Commons Network^™

An Examination Of Psychological Climate Linking Mechanisms Across The Strategic Priorities Of Health And Stress, Alec Munc

All Dissertations

Given that employee health and well-being represent a significant source of financial costs for organizations, this dissertation seeks to address some of the pathways through which organizational efforts to improve physical and mental health may operate. This study drew from a model of safety climate (Neal & Griffin, 2000) to propose that psychological climate exerts in influence on employee health and well-being through the joint moderators of knowledge/motivation and behaviors. The model also extended beyond the typical climate linking mechanisms to include moderators both individual (behavioral activation & behavioral inhibition systems) and contextual (workplace physical exposure). Using a two-wave prospective …

Estimating The Effect Of Extended And Emergency Unemployment Benefits On The Long-Term Unemployed, James Jones

All Dissertations

Unemployment insurance is designed to help workers smooth consumption in the event of a negative employment shock. These benefits are traditionally funded and administrated by the individual states and territories of the United States. The depth and severity of the “Great Recession” that started in December of 2007 and ended in June of 2009 was such that, Congress was compelled on multiple occasions to extend those benefits. Legislation during this period extended the duration of unemployment benefits to the longest period in history, as unemployed individuals in many states could receive up to 99 weeks of unemployment compensation. The policy …

Understanding The Automotive Pedal Usage And Foot Movement Characteristics Of Older Drivers, Yubin Xi

All Dissertations

The purpose of this study was to understand the pedal usage characteristics of older drivers in various driving tasks using an instrumented vehicle. This study stemmed from the prevalence of the pedal application errors (PAEs) and the older drivers’overrepresentation in crashes caused by PAEs.

With the population increasing and becoming older, it is estimated that in 2020 there will be 40 million drivers over the age of 65 in the United States. Compared with their younger counterparts, older drivers are facing declining cognitive and physical abilities, such as impaired vision, slower reaction time and diminishing range of limb motion. Because …

Interacting Partners Of The Sunn Symbiotic Kinase, Ashley Dawn Zearfoss Crook

All Dissertations

The control of nodule number in legumes is primarily accomplished through a complex systemic signaling pathway termed autoregulation of nodulation (AON). The protein kinase SUNN, a leucine-rich repeat receptor-like kinase, exhibits shoot control of AON. I show subcellular localization of SUNN to the plasma membrane and specifically to the plasmodesmata, a prime location for systemic signaling. To aid in better understanding the mechanisms of signaling in AON, I used different approaches to identify potential protein-protein interactions involving SUNN, including candidate genes, exploratory proteomics, and forward genetic screens. Candidate interactors, including CLAVATA2 (CLV2), CORYNE (CRN) and guanine exchange factors of the …

Anisotropic Stimuli-Responsive Polymeric Nanoparticles: Synthesis And Characterization, Chunliang Lu

All Dissertations

This dissertation focuses on the design, synthesis and characterization of stimuli-responsive anisotropic nanoparticles with various morphologies. Size- and shape-tunable Janus nanoparticles consisting of poly(methyl methacrylate/n-butyl acrylate) (p(MMA/nBA)), poly(pentafluorostyrene/nBA) (p(PFS/nBA) and poly(2-(N,N′-dimethylamino) ethyl methacrylate/nBA) (p(DMAEMA/nBA)) phases were synthesized via consecutive seeded emulsion polymerization. These Janus nanoparticles are capable of changing size and morphology in response of temperature and/or pH changes, which may have potential applications as solid surfactants. Gibbous and inverse-gibbous nanoparticles were synthesized viacopolymerization of fluorinated monomers in the presence of pMMA or polystyrene (pSt) seed particles. The morphology of the gibbous nanoparticles can be controlled by polymerization conditions. Incorporation …

Filtering Impulses In Dynamic Noise In The Presence Of Large Measurement Noise, Jungphil Kwon

All Dissertations

This work considers the problem of filtering a system in which the dynamic noise occasionally has an impulse value that is an order of magnitude or more larger than its typical expected distribu-tion. This is particularly challenging when the ratio of measurement noise to typical dynamic noise is large enough that the impulse dynamic noise cannot be easily distinguished from a large random occurrence of measurement noise. A new filter model is proposed using a multiple model approach in which one of the models is an impulse. The implementation of the model is demonstrated in a Kalman filter framework. Simulation …

A Framework For Designing Of Electric Vehicle Charging Infrastructure Network, Shengyin Li

All Dissertations

The lack of sufficient public charging stations for electric vehicles has long been recognized as a major hinder for massive adoption of electric vehicles (EV). This dissertation aims to develop a framework for designing charging station infrastructure networks that electric vehicle with limited travel range can be recharge en-route to complete trips to destinations and then would facilitate the adoption of electric vehicles. The rest part of this dissertation is concerned with modeling travel range of electric vehicle and users behavior of deviating from their most preferred routes when siting charging stations. The proposed multi-path refueling location model provides the …

Development And Implementation Of The Generations Eating Together Through Cooking (G.E.T.T. Cooking) Curriculum And Its Effects On An Inter-Generational Population: A Pilot Study, Elizabeth Ramirez

All Dissertations

The obesity epidemic continues to be a problem both in the US and worldwide. A number of factors have been attributed including: frequency of fast-food consumption, increased portion sizes, increased consumption of sugar-sweetened beverages, increased sedentary lifestyles, lack of nutrition knowledge, and lack of cooking skills. Nutrition intervention programs continue to be created providing innovative and creative ways of educating the public with pertinent knowledge and skills necessary for improving healthful behaviors; however, few programs focus on cooking skill development within a familial environment. The Generations Eating Together Through Cooking (G.E.T.T. Cooking) program was created by the lead researcher as …

Nematicidal Activity Of Extracts From Phytolacca Americana On Five Plant-Pathogenic Nematode Species Of Economic Importance, Saleh Ahmed

All Dissertations

Plant-parasitic nematodes cause significant losses to plant agriculture annually. The limited availability and high cost of synthetic nematicides, along with the environmental risks associated with their use, have created a renewed interest in the search for alternative management tactics. One such alternative tactic is the use of plant extracts. The focus of this research is the evaluation of the nematicidal activity of water extracts from Pokeweed (Phytolacca americana). In vitro and greenhouse tests were performed to evaluate the effects of the extracts on five species of plant-pathogenic nematodes of economic importance: Aphelenchoides fragariae, Ditylenchus dispsaci, Meloidogyne incognita, Pratylenchus penetrans, and …

Examining The Space-Time Constraints Concept On Tourist Behavior For Visitors To The South Carolina Coastal Area Of The United States, Sanghoon Kang

All Dissertations

This dissertation explored three themes with regard to the spatial aspects of tourist behavior, conducting three independent analyses. For these analyses, this dissertation research adapted Shoval's (2012) definition of the space-time constraints concept developed by Hagerstrand (1970): the purpose of trip (i.e., authority constraints), the length of visit (i.e., capability constraints), and the composition of travel party (i.e., coupling constraints). The purposes of the three analyses were to examine the relationships 1) between the space-time constraints and the spatial patterns of travel; 2) between ICT use (i.e., smartphones) and the spatial patterns of travel, space-time constraints, tourists' unplanned destination visits, …

Electromechanical Modeling Of A Honeycomb Core Integrated Vibration Energy Converter With Increased Specific Power For Energy Harvesting Applications, Nataraj Chandrasekharan

All Dissertations

Innovation in integrated circuit technology along with improved manufacturing processes has resulted in considerable reduction in power consumption of electromechanical devices. Majority of these devices are currently powered by batteries. However, the issues posed by batteries, including the need for frequent battery recharge/replacement has resulted in a compelling need for alternate energy to achieve self-sufficient device operation or to supplement battery power. Vibration based energy harvesting methods through piezoelectric transduction provides with a promising potential towards replacing or supplementing battery power source. However, current piezoelectric energy harvesters generate low specific power (power-to-weight ratio) when compared to batteries that the harvesters …

Developing Effective Ground And Space-Based Soil Moisture Sensing Techniques For Irrigating Cotton In Coastal Plain Soils, Xin Qiao

All Dissertations

Irrigation scheduling based on soil moisture sensor readings has gained popularity in the past few decades since it can enhance crop yield while saving water. Such method is limited since the representativeness of an individual soil moisture sensor measurement is questionable in a large field with variable soil type and texture. The optimum location of soil moisture sensors needs to be determined within such a production field for effective sensor-based irrigation scheduling. Therefore, the first object of this study was to investigate the optimum sensor location and the number of moisture sensors required for irrigating cotton in coastal plain soils. …

Exploring Elementary Teachers’ Conceptions Of Global Citizenship Through Cross-Cultural Interaction, Sheliah Durham

All Dissertations

The challenge we face as educators is how to best prepare our students for an increasingly complex and interconnected world. A growing interest in global citizenship education is evidenced by its inclusion in academia related to curriculum development and teacher preparation (Banks, 2008; Merryfield, 2000; 2001; 2003; 2009; Myers, 2006; Nussbaum, 2002). I, following other scholars, argue that global citizenship education provides an opportunity to develop tolerances, appreciation for differences, and global awareness, as well as providing a format to address current and future global issues (Ikeda, D. 2005; Noddings, 2005a; Merryfield 2000; 2007; 2009). Yet, a review of the …

Multi-Factor Models To Resolve Growth Responses In Vitro And During Subsequent Greenhouse Growth For Turmeric (Curcuma Longa L.), Rabia El-Hawaz

All Dissertations

Plant media has been developed over the last six decades, yet, there has not been medium optimized for microplant greenhouse growth, which may be important for producing chemical compounds and preparing transplants for success in the field. A series of multi-factor optimization experiments were conducted on turmeric (Curcuma longa L., genotype L 35-1) to identify the effects of mineral nutrition and plant density in vitro on laboratory and greenhouse production. The first experiment optimized PO43-, Ca2+, Mg2+, and KNO3 for five-months growth in bioreactors with periodic supplementation of sucrose solution +/- nutrients. Phosphorus (6.25 mM) increased sucrose supplement and rhizome …

Effects Of Semi-Rigid Plastic Tray Geometry On Thermal Processing And Quality Factors In Retorted Foods, Curtis Stowe

All Dissertations

This research studied the effect of packaging geometry changes on heat penetration and quality attributes of a food system processed in a rotary retort vessel. Studies were conducted to determine the effect of package geometry in a rotary retort on heat penetration, analytical, and physical properties of a model food system processed at optimum conditions. Additionally, heat mapping for each shape was used to determine the heating profiles during retorting. Retort-able trays were filled with a tomato based food simulate and thermally processed in a water immersion, automated batch retort system (ABRS) using rotational speeds of 6 RPM and 11 …

Iterative Design And Testing Of A Mobile Application To Support Food Consumption Monitoring And Decision Making, Melva James

All Dissertations

Food overconsumption is a major contributor to weight gain leading to obesity. Constant exposure to larger amounts of food and beverage has caused many individuals to experience “portion distortion,” the perception that bigger portion sizes are appropriate for consumption at a single sitting. Independently and accurately changing this perception can be very difficult even if one has a desire to do so. In response to these observations, we developed and tested Picture-Perfect Portions, a mobile application designed to combat overconsumption, at the individual level, by leveraging the power of simple visualizations to help adults understand and adjust their food consumption …

Development Of A Miniaturized Ambient Glow Discharge Ionization Source And Its Application In Elemental And Molecular Analysis, Xinyan Zhang

All Dissertations

Since the liquid sampling-atmospheric pressure glow discharge (LS-APGD) was first developed as an excitation source for atomic emission spectroscopy, it has been improved upon and demonstrated as an ionization source for elemental mass spectrometry, molecular mass spectrometry, and ambient desorption mass spectrometry. Multiple functions coming from one package allowed the LS-APGD to hold a unique position among all atmospheric pressure glow discharges. It also has the capabilities to work with different sample forms including liquids, bulk solids, and solution residues. The high salt/matrix tolerance reduces sample prep work and thus provides convenience for its potential use as a field-Based ionization …

Bayesian Minimum Description Length Techniques For Multiple Changepoint Detection, Hewa Anuradha Priyadarshani

All Dissertations

This dissertation develops a minimum description length (MDL) multiple changepoint detection procedure that allows for prior distributions. MDL methods, which are penalized likelihood techniques with penalties based on data description-length information principles, have been successfully applied to many recent multiple changepoint problems. This work shows ow to modify the MDL penalty to account for various prior knowledge. Our motivation lies in climatology. Here, a metadata record, which is a file listing times when a recording station physically moved, instrumentation was changed, etc., sometimes exists. While metadata records are notoriously incomplete, they permit the construct a prior distribution that helps detect …

Synthesis And Characterization Of Oleophobic Fluorinated Polyester Films, Tugba Demir

All Dissertations

The study presented in this dissertation is dedicated to the synthesis and characterization of oleophobic fluorinated polyester films. Specifically, the blending of oleophilic polyethylene terephthalate (PET) with low surface energy materials such as fluorinated polyesters has been used in order to fabricate oleophobic PET films. First, fluorinated polyesters (P(PF-oate-R)) possessing different end-groups (-COOH, -OH and -CF3) are synthesized via polycondensation reaction of isophthaloyl chloride with perfluoro ether alcohols. Then, they are solvent-blended with PET at various concentrations to obtain oleophobic polyester films of different compositions. In addition, the films are annealed to investigate the effect of annealing on surface properties …

The Detection And Characterization Of Some Viruses Infecting Blackberry And Cherry In South Carolina, Bindu Poudel

All Dissertations

Three separate virus research projects were conducted. Blackberry yellow vein disease (BYVD), a disorder caused by virus complexes, has become a major threat to blackberry production in the United States, especially in the southeastern part of the country where blackberries are grown for the fresh market. More than 30 viruses have been found to be associated with the disease. Most of these induce no symptoms when infecting the plant alone. However, when more than a single virus is present in the host visible symptoms are displayed. The incidence of 6 different viruses (Blackberry yellow vein-associated virus, Blackberry virus Y, Blackberry …

Bombardment Simulations And Intercalation Studies Of Carbon Materials, Charles Lowe

All Dissertations

Molecular bombardment experiments have led to the possibility of altering materials with properties not normally associated with those materials. Molecular bombardment leads to defect formation in the material, potentially creating a pore, depending on the material and bombarding molecule. Carbon allotropes, specifically graphite and graphene, make excellent candidates for molecular bombardment experimentation. Depending on the bombarding molecule and the kinetic energy associated with that molecule, the defects induced will be sufficient to create a pore in the graphene. The AIREBO potential is used to simulate a graphene bilayer being bombarded with a single Ar atom, or a fullerene molecule, to …

Creating Arguments Using A Multiliteracies Approach: A Formative Experiment, Emily Howell

All Dissertations

This dissertation study addresses the New London Group’s (1996) concern that technology and globalization require an expanded concept of literacy that focuses upon the multimodal nature of communication. This study combined a formative experiment with multiple-case-study methods to understand the pedagogical implications of implementing an intervention based upon the multiliteracies perspective (New London Group, 1996), a perspective that remains theoretical in application. This study sought to implement this perspective in a ninth- and a tenth-grade English class in a rural school district and develop assertions that further the localized, pedagogical understanding and application of the present study’s intervention (Gravemeijer & …

Integrated Coherent Combining Of Angled-Grating Broad-Area Lasers: Design, Fabrication And Characterization, Yunsong Zhao

All Dissertations

In this thesis, we proposed, fabricated and demonstrated the coherent beam combining of angled-grating broad-area lasers. We have obtained the simultaneous coherent beam combining and single transverse mode operation completely on chip without any external phase control/components. Since the single transverse mode is the key to obtain diffraction-limit beam quality and high brightness, the proposed design is a good candidate for high power and high brightness applications. In the proposed coherently combined laser array, we use the angled-grating broad-area laser as the building block and overlap the adjacent emitters at one facet. The overlapped region becomes a 2D coupling region. …

Production And Characterization Of Cut Resistant Acrylic/Copolyaramid Fibers Via Bicomponent Wet Spinning, Stephen Hipp

All Dissertations

A composite fiber system consisting of a sheath core bicomponent polymer fiber loaded with hard ceramic particles was developed and characterized for use in cut protective clothing. The core component was comprised of a copolyaramid in order to provide high base cut resistance. An acrylic-copolyaramid polymer blend was used for the sheath component to improve processability and provide potential benefits such as dyeability. Lastly, aluminum oxide particles were incorporated into the fiber core to deflect and deform the cutting edge, further improving cut resistance. A series of designed experiments was used to explore the effects of the wet spinning and …

A Study On General Assembly Line Balancing Modeling Methods And Techniques, Bryan Pearce

All Dissertations

The borders of the assembly line balancing problem, as classically drawn, are as clear as any other operations research topic in production planning, with well-defined sets of assumptions, parameters, and objective functions. In application, however, these borders are frequently transgressed. Many of these deviations are internal to the assembly line balancing problem itself, arising from any of a wide array of physical or technological features in modern assembly lines. Other issues are founded in the tight coupling of assembly line balancing with external production planning and management problems, as assembly lines are at the intersection of multiple related problems in …

Proportioning And Properties Of Ultra-High Performance Concrete Mixtures For Application In Shear Keys Of Precast Concrete Bridges, Zhengqi Li

All Dissertations

Ultra-high performance concrete (UHPC) is defined as a cementitious based composite material with compressive strengths above 150 MPa, pre-and post-cracking tensile strengths above 5 MPa, and enhanced durability. To achieve desired properties, UHPC is typically produced with low water-cementitious materials (w/cm) ratio (i.e. w/cm < 0.25), high cementitious materials content (i.e. >1000 kg/m3), high quality aggregate, high dosage of high-range water reducing admixture (HRWRA) and reinforcing fibers. UHPC has distinct advantages in applications where narrow formwork and dense reinforcement are inevitable, high compressive strength concrete material is required and the surrounding environment is aggressive. The construction of shear keys in precast bridges is one of the important …

Configuration Management In Manufacturing And Assembly: Case Study And Enabler Development, Keith Phelan

All Dissertations

The overall goal of this research is to improve the product configuration change management process. The increase in the demand for highly customizable products has led to many manufacturers using mass customization to meet the constantly changing demands of a wide consumer base. However, effectively managing the configurations can be difficult, especially in large manufacturers or for complex products with a large number of possible configurations. This is largely due to a combination of the scope of the configuration management system and the difficulty in understanding how changes to one element of a configuration can propagate through the configuration system. …

Electrochemical Enhancement Of Butanol Production And Xylose Consumption In Pure And Mixed Culture Fermentations, Jovan Popovic

All Dissertations

The volatility of foreign and domestic petroleum markets has prompted initiatives for the development of alternative liquid energy carriers which have the capacity to accommodate our current transportation infrastructure. Butanol, which has an energy density similar to that of gasoline and can be produced through the fermentation of carbohydrates by solventogenic Clostridia, has been investigated as a supplement or direct replacement to gasoline. However, most butanol fermentations rely on glucose as a feedstock which is in direct competition with our food supply, and this requires the exploration of alternative fermentable substrates. This study investigates the use of electrochemical fermentation modifications …

Microrna-Mediated Plant Development And Response To Environmental Stress In Perennial Grasses, Shuangrong Yuan

All Dissertations

World population will pass nine billion by 2050, while the agricultural land area will not increase dramatically in the coming decades. To meet the ever-increasing food demand, genetically engineered crops have been rapidly adopted for crop productivity. MicroRNAs have become increasingly attractive as targets in crop genetic modification due to their regulatory role in fine-tuning many essential biological processes. My research explores the potentials of microRNA528 (miR528) and miR396 for use in genetic modifications of the important agronomic traits of plant development, abiotic stress response, and/or flowering time control in an economically and environmentally important perennial monocot species, creeping bentgrass …

On Subgrid-Scale Physics In The Convective Atmospheric Surface Layer, Khuong Nguyen

All Dissertations

The dynamics of the subgrid-scale (SGS) stress and scalar flux in the convective atmospheric surface layer are studied using field measurements from the Advection Horizontal Array Turbulence Study (AHATS). We extend the array technique previously used to evaluate the SGS velocity and temperature to include measurements of the fluctuating pressure, enabling separation of the resolvable- and subgrid-scale pressure and allowing for the first-ever observations of the pressure covariance terms and the full SGS budgets. Non-dimensional forms of the budget terms are analysed as functions of the surface-layer stability parameter and the ratio of the wavelength of the spectral peak of …