Digital Commons Network^™

What Is The Participant Learning Experience Like Using Youtube To Study A Foreign Language?, Yuan-Hsiang Lo

Graduate Theses and Dissertations

This research is to explore and understand participants' experience using YouTube to learn a foreign language. YouTube and learning has become more and more popular in the recent years. The finding of this research will be adding more understanding to the emerging body of knowledge of YouTube phenomenon. In this research, there are three interviews and two questionnaires. The interviews are conducted to find in-depth responses from participants; the questionnaires are used to inquire demographic and basic information about the participants. There are twelve themes found in this research. These themes reflect on the perceived experience using YouTube to learn …

Thermal And Electrical Parasitic Modeling For Multi-Chip Power Module Layout Synthesis, Zihao Gong

Graduate Theses and Dissertations

This thesis presents thermal and electrical parasitic modeling approaches for layout synthesis of Multi-Chip Power Modules (MCPMs). MCPMs integrate power semiconductor devices and drive electronics into a single package. As the switching frequency of power devices increases, the size of the passive components are greatly reduced leading to gains in efficiency and cost reduction. In order to increase switching frequency, electrical parasitics in MCPMs need to be reduced through tighter electronic integrations and smaller packages. As package size is decreased, temperature increases due to less heat dissipation capability. Thus, it is crucial to consider both thermal and electrical parasitics in …

New Applications Of Mass Spectrometry For Drug And Lipid Analysis, Elizabeth Lauren Emerson

Graduate Theses and Dissertations

Mass spectrometry is an important tool used in many different disciplines and settings that include forensics, drug discovery, environmental analysis, and proteomics. Gas chromatography - mass spectrometry (GC-MS) and matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI - TOF MS) are two of the most important instruments used for analysis of compounds. Chapters 1 and 2 of this discussion use GC-MS for the investigation of synthetic cannabinoids in `K2' incense products and the detection of metabolites in urine samples from individuals suspected of consuming these mixtures. Analytical standards were synthesized and used for identification and confirmation of structures. Detection of …

The Role Of Centromeric Chromatin And Kinetochore-Associated Factors In Chromosome Segregation, Wesley Williamson

Graduate Theses and Dissertations

Previous work in our lab has identified a point mutation in HTA1, one of the genes encoding histone H2A, which causes an increase-in-ploidy phenotype in Saccharomyces cerevisiae. This histone mutant strain was used to carry out a transposon insertion screen to identify suppressors of the increase-in-ploidy phenotype. This screen identified all three subunits of the Hda histone deacetylase complex, HDA1, HDA2, and HDA3. This study aims to elucidate the function of the Hda complex in chromosome segregation by exploring interactions among the members of the complex, as well as interactions between Hda complex and kinetochore components. …

Optimization Of Nonlinear Switch Cells For Switching Converters, Bradley Alan Reese

Graduate Theses and Dissertations

Switch cells consist of an array of power switches and passive components which can replace the main switches alone in many power topologies, allowing reduced switching loss without altering the power topology directly. This thesis discusses the development of a switch cell topology that utilizes a saturable resonant inductor to reduce the size and power loss of the cell. Additionally, the cell transfers energy stored in the inductor into a capacitor for efficient energy storage during the cell's conduction region. This energy is then transferred back to the system when the cell turns off, thus reducing the total switching energy.

Risk Analysis And Reliability Improvement Of Mechanistic-Empirical Pavement Design, Xingqiang Danny Xiao

Graduate Theses and Dissertations

Reliability used in the Mechanistic Empirical Pavement Design Guide (MEPDG) is a congregated indicator defined as the probability that each of the key distress types and smoothness will be less than a selected critical level over the design period. For such a complex system as the MEPDG which does not have closed-form design equations, classic reliability methods are not applicable. A robust reliability analysis can rely on Monte Carlo Simulation (MCS). The ultimate goal of this study was to improve the reliability model of the MEPDG using surrogate modeling techniques and Monte Carlo simulation.

To achieve this goal, four tasks …

Improved Protocols For Automated Wheelpath Crack Detection In Pavements, Daniel Patrick Byram

Graduate Theses and Dissertations

Roadway pavement distress evaluations are vital to understanding the mechanics of pavement stability, determining the distribution of rehabilitation costs, and knowing the appropriate rehabilitation strategies. Advancements in technology over the past two decades have changed the way these surveys have been performed by means of automated data collection and interpretation. More and more state agencies have invested in automated road analyzing vehicles that are able to collect high resolution images of the pavement. Fewer have adopted automated data processing software with the ability to interpret road distresses due to the common discrepancies in distress classification algorithms.

In addition to automated …

New Insights Into Disinfection Byproduct Formation And Control: Assessing Dissolved Organic Matter Diffusivity And Chemical Functionality, Ashley Pifer

Graduate Theses and Dissertations

Methods were developed for application of asymmetric flow field-flow fractionation (AF4) and fluorescence parallel factor (PARAFAC) analysis to raw and treated samples from drinking water sources to improve characterizations of dissolved organic matter (DOM) and discover DOM properties correlated to disinfection byproduct (DBP) formation potential (FP). Raw water samples were collected from a reservoir, adjusted to pH 6, 7, and 8 and subjected to (1) jar tests using aluminum sulfate (alum) and (2) treatment with magnetic ion exchange (MIEX^®) resin. Both treatments were followed by DBPFP tests at pH 7. AF4 was used to size DOM in raw …

Assessing Knowledge Acquisition Through Lecture And Cooperative Learning: Traditional And Non-Traditional Secondary Students In Agriculture, Beth Ann Jean Bills-Hunt

Graduate Theses and Dissertations

Currently, students entering secondary agricultural education programs have less knowledge and hands-on experience about agriculture than previous generations. Agricultural educators are challenged to vary teaching practices to meet student needs. The purpose of this study was to determine if there is a difference in knowledge acquisition between students enrolled in secondary agricultural education classes taught by cooperative learning and lecture instruction. Additionally, this study explored the knowledge acquisition of traditional and non-traditional secondary agricultural education students and perceptions of instructional methods presented. Eight schools participated in the study. No significant difference was seen in test scores between methods of instruction, …

Locating And Protecting Facilities Subject To Random Disruptions And Attacks, Hugh Medal

Graduate Theses and Dissertations

Recent events such as the 2011 Tohoku earthquake and tsunami in Japan have revealed the vulnerability of networks such as supply chains to disruptive events. In particular, it has become apparent that the failure of a few elements of an infrastructure system can cause a system-wide disruption. Thus, it is important to learn more about which elements of infrastructure systems are most critical and how to protect an infrastructure system from the effects of a disruption. This dissertation seeks to enhance the understanding of how to design and protect networked infrastructure systems from disruptions by developing new mathematical models and …

The Price Of Dissent: Freedom Of Speech And Arkansas Criminal Anarchy Arrests, Jamie Leto Kern

Graduate Theses and Dissertations

Following World War I and the Bolshevik Revolutions, America's Red Scare began, inciting fanatical patriotism and an alleged threat of anarchy that gripped a nation with fear. Paranoia about communists, Socialists, and anarchists divided the country and resulted in many states, including Arkansas, passing criminal anarchy laws. Since a majority of those accused of anti-American activities were involved in labor disputes, Arkansas makes for an interesting case study; not only did it have a relative lack of labor disputes, it still passed anti-Bolshevik laws. The purpose of this research is to develop an understanding of the ways in which dissenters …

An Exploration Of Social Media Use In Local Television News Stations: An Evaluation And Development Of A Successful New Media Strategy, Aniseh Ebbini

Graduate Theses and Dissertations

This paper examines the ways in which Social media have gained popularity over the last decade, amongst the public, and especially in the television news industry. After evaluating the current ways Social media are being implemented and observing national trends, I developed a comprehensive new media strategy to serve as a guide and reference for any television station wanting to incorporate these tools into its regimen.

Food Environment And Childhood Obesity, Yucong Jiao

Graduate Theses and Dissertations

This thesis examines whether children's food environment, especially food stores that have fresh produce, affects obesity prevalence among elementary school children in the state of Arkansas. Misclassified food outlet types in the Dun and Bradstreet commercial data set were first corrected and then food environment measures were computed and aggregated to geographic regions corresponding to school attendance areas. After applying classical panel estimation, it was found that the fixed effects model fit the data best. Results indicate that an additional supermarket within a one-mile radial of the census neighborhood block center will bring down childhood obesity prevalence by 0.58 percent, …

Optimization Models And Algorithms For Truckload Relay Network Design, Hector Andres Vergara Arteaga

Graduate Theses and Dissertations

Driver turnover is a significant problem for full truckload (TL) carriers that operate using point-to-point (PtP) dispatching. The low quality of life of drivers due to the long periods of time they spend away from home is usually identified as one of the main reasons for the high turnover. In contrast, driver turnover is not as significant for less-than-truckload (LTL) carriers that use hub-and-spoke transportation networks which allow drivers to return home more frequently. Based on the differences between TL and LTL, the use of a relay network (RN) has been proposed as an alternative dispatching method for TL transportation …

Cell Bioenergetics In Leghorn Male Hepatoma Cells And Immortalized Chicken Liver Cells In Response To 4-Hydroxynonenal Induced Oxidative Stress, Alissa Laura Piekarski

Graduate Theses and Dissertations

Bioenergetic mechanisms responsible for ATP production are essential in carrying out maintenance and cell-specific functions. In this study, hepatocytes (liver cells) were used to test both endogenous and exogenous stress on cellular respiration. The secondary lipid peroxide, 4-hydroxynonenal (HNE), was used because it alters bioenergetics by increasing mitochondrial proton leak that attenuates mitochondrial radical production and, therefore, endogenous oxidative stress. The major objective of this study was to demonstrate effects of HNE-induced oxidative stress on avian hepatocyte bioenergetics. Various chemical which help enable the determination of oxygen (O2) consumption linked to ATP synthesis (oligomycin), maximal O2 consumption (FCCP), and proton …

Fabrication And Characterization Of Thinner Solid-State Nanopores, Denis Forbi Tita

Graduate Theses and Dissertations

Solid State nanopores that are fabricated by the ion beam sculpting process and electron beam drilling have shown great promise as a sensing device for DNA and protein molecules. Even though biological pores such as the alpha-Haemolysin have been in use for quite some time, the use of solid state Nanopores in single biomolecule detection has been on the rise since the mid 1990s. Solid State nanopores have an advantage over biological pores in that they are more robust, stable, and can be sculpted to any desired size for use in translocation experiments. One of the major challenges in Nanopore …

Contextual Influences On Small Group Decision-Making: A Field Investigation, Sarah Kathryn Chorley

Graduate Theses and Dissertations

This thesis examines small group decision-making among groups of educators in an elementary school through the Bona Fide Group Perspective, which focuses on a group and its relationships to elements in its context. Twenty-six faculty members were interviewed and 26 meetings were recorded; these were analyzed using thematic analysis. The results indicated contextual, relational, and discursive factors influenced the decision-making process. Most critically, power, status, overlapping group memberships, and competing Discourses shaped the group decision-making process.

Evaluation Of Internal Markers For Predicting Digestibility And Fecal Output By Cattle Fed Bermudagrass Hays Of Varying Quality, Juvenal Kanani

Graduate Theses and Dissertations

The potential of in situ rumen undegradable dry matter (RUDM), indigestible neutral-detergent fiber (INDF), indigestible acid-detergent fiber (IADF), acid-detergent insoluble ash (ADIA), alkaline-peroxide lignin (APL), and acid-detergent lignin (ADL) to predict digestibility (DMD) and fecal output (FO) by cattle fed bermudagrass [Cynodon dactylon (L.) Pers.] hay-diets categorized by their low (L), medium low (ML), medium high (MH), or high (H) CP concentrations (79, 111, 131, and 164 g/kg DM, respectively) was evaluated. The second objective was to evaluate the effects of time (0600, 1200, 1800, and 2400 h) of fecal sampling on the prediction of FO and DMD. A replicated …

Gendered Effects On The Child Welfare Agency Decision-Making Process, Brandon Crawford

Graduate Theses and Dissertations

Previous research on child abuse and neglect suggests that there may be gendered relationships between child victims and case outcomes. Specifically, although agency practices may generally regard most male and female children as equally vulnerable, agency attributions regarding the culpability, need, and suitability of parents may be highly differentiated based on gender. Explanations for this pattern may lie in the cultural ideologies and organizational beliefs that distinguish between the perceived rights, responsibilities, and relative importance of mothering and fathering roles. That is, one function of Social service agencies is to uphold Social constructions of parenting and promote our larger cultural …

The Effects Of First-Year Students' Self-Perceptions Of Behaviors, Attitudes, And Aptitudes On Their First-To-Second-Year Persistence, Rebecca Jean Lambert

Graduate Theses and Dissertations

Student persistence continues to be a topic of much research and discussion in higher education. Based on Bean and Eaton's (2000) psychological theory of persistence for its theoretical framework, this study examined the effect of students' demographic and background characteristics and students' self-perceptions on their first-to-second-year persistence at a small, private, faith-based institution. Demographic and background characteristics examined were gender, race/ethnicity, first-generation college student status, high school GPA, and type of high school attended. Four constructs from the CIRP Freshman Survey were used to examine student self-perceptions: (a) Habits of the Mind, (b) Academic Self-concept, (c) Social Self-concept, and (d) …

Ultra-Low Voltage Digital Circuits And Extreme Temperature Electronics Design, Aaron J. Arthurs

Graduate Theses and Dissertations

Certain applications require digital electronics to operate under extreme conditions e.g., large swings in ambient temperature, very low supply voltage, high radiation. Such applications include sensor networks, wearable electronics, unmanned aerial vehicles, spacecraft, and energyharvesting systems. This dissertation splits into two projects that study digital electronics supplied by ultra-low voltages and build an electronic system for extreme temperatures. The first project introduces techniques that improve circuit reliability at deep subthreshold voltages as well as determine the minimum required supply voltage. These techniques address digital electronic design at several levels: the physical process, gate design, and system architecture. This dissertation analyzes …

The Impact Of Selected Forage Legumes On Cattle Performance, Forage Production, And Soil Quality, And Evaluation Of Legume Persistence Under Grazing, Bradley Edward Briggs

Graduate Theses and Dissertations

Interest in substituting legumes for N fertilizer in beef cattle grazing systems has recently increased with rising fertilizer prices. Legumes are well known for their ability to fix atmospheric N and decrease dependence on input of N fertilizer. However, there are still difficulties associated with legume utilization including establishment and persistence. Two experiments were conducted to evaluate legume performance under herbivory. The objective of Experiment 1 was to compare forage production and beef cattle gains from annual ryegrass [Lolium multiflorum (L.)] and bermudagrass [Cynodon dactylon (L.) Pers.] pastures fertilized with N or overseeded with legumes. Gelbvieh × Angus …

Performing Literacy: How Women Read The World In The Late Eighteenth-Century British Novel, Amy Hodges

Graduate Theses and Dissertations

This dissertation explores the intersection of sensibility, Social identity, and literacy practices among representations of women readers in four late eighteenth-century British novels. Through an analysis of the authors' use of identity constructs which shaped and were shaped by reading practices, this study documents the rise of Social identity formation as mutually constitutive with the history of reading. The first chapter reveals how Charlotte Lennox's The Female Quixote uses Arabella's follies as education for readers about the corresponding processes of reading their society and reading novels. The second chapter argues that Frances Burney's Evelina considers women's ability to read others …

Interactions Between The Thermic Effect Of Food And Exercise On Total Energy Expenditure In Moderately Active Females, Ashley Binns

Graduate Theses and Dissertations

Diet and exercise are key components to overall health maintenance. Aspects contributing to weight maintenance include the thermic effect of food (TEF) and total energy expenditure (TEE), with TEF contributing to upwards of 10% TEE. PURPOSE: The purpose of this study was to determine the interaction between TEF and exercise on TEE in moderately active females. METHODS: A sample population was established with the use of a health history questionnaire (HHQ). Ten active females of normal body composition, determined by body mass index (BMI) and a dual energy absorptiometry x-ray (DEXA) scan, participated in the study. Maximal aerobic …

Stability Of Phyllosilicates On Mars, Patricia Gavin

Graduate Theses and Dissertations

This study investigates the stability of phyllosilicates on the surface of Mars through laboratory experiments and analysis of terrestrial analogs. Phyllosilicates are mostly found in the oldest Noachian terrains on Mars and hence hold clues to the planet's earliest aqueous and geologic history. Phyllosilicates relevant to Mars were heated up to ~1100°C for up to 24 hours and impacted with projectile velocities up to ~4.5 km/s. Heated samples were analyzed using x-ray diffraction (XRD) and Fourier Transform Infrared (FT-IR) spectroscopy in the near- (NIR, 1.0-2.5 µm) and mid-infrared (MIR, 5.0-15.0 µm) ranges. Impacted samples were also analyzed using Raman spectroscopy …

The Competitive Front-Of-Package Labeling Of Consumer Packaged Goods: Cutting Through The Clutter, Christopher Newman

Graduate Theses and Dissertations

At no point in U.S. history have food product packages displayed so many symbols and statements regarding nutrition and health benefits (Nestle 2010). However, despite this explosion of front-of-package (FOP) health communications, obesity and health-related problems of U.S. consumers continue to be a critical concern. Therefore, it is important for marketers, retailers, manufacturers, and public policy makers to develop a more complete understanding of consumers' processing and utilization of health information on food packages, as well as how this information affects product evaluations and choices.

Therefore, this dissertation utilizes a processing fluency theoretical framework (e.g., Zajonc 1968; Jacoby and Dallas …

A Daily Temperature Record For Central Texas, 1896-2011, Matthew Kain Taylor

Graduate Theses and Dissertations

A continuous record of 882,693 daily maximum, minimum, and mean temperature measurements for seven weather stations in central Texas dating from August 1, 1896, to August 31, 2011, were screened and corrected for missing values and inhomogeneities. The resulting data were averaged to create a 115-year unbroken regional record of daily temperature for central Texas. This record indicates warming in daily, seasonal, and annual temperatures. Winter warm temperature extremes have increased over the period of record while warm temperature extremes during the summer months have remained largely unchanged. Summer heat wave days and the length of heat waves have increased …

Relationship Of Polymorphisms In The Fsh Beta Subunit Gene With Reproduction In Bos Taurus And Bos Indicus Cattle, Amanda Jo Davis

Graduate Theses and Dissertations

Two experiments were conducted to characterize polymorphisms (SNP) in the bovine FSHβ gene promoter region to examine breed differences in SNP, and to determine effects of SNP on reproduction in beef cattle. Experiment 1 - DNA samples were collected from 5 Angus (ANG), 13 Balancer (BAL), & 16 Brahman influenced (BI) bulls. Polymorphisms were identified by sequencing of 3 sequential PCR products from the promoter region revealed 17 SNP & 4 insertion/deletions (INDEL). Semen samples were collected and sperm quality variables determined via computer assisted sperm analysis (CASA) or stained smears. The MIXED procedure for ANG & BAL indicated interactions …

Gain Of A Single Gas Electron Multiplier, Mythra Varun Nemallapudi

Graduate Theses and Dissertations

Gas Electron Multiplier (GEM) is a gaseous detector used in particle detection and is known for its high rate capability. Ever since its invention in 1997, GEM was applied in many areas and recently has been proposed to be installed in the CMS high η regions for upgrade at LHC, CERN. A complete understanding of the working and gain behaviour does not exist. GEM gain is influenced by charging up and this has been variedly interpreted in literature lacking consensus. I have attempted in this work through simulations and measurements to achieve a better understanding of single GEM gain and …

Delay Insensitive Ternary Logic Utilizing Cmos And Cntfet, Ravi Sankar Parameswaran Nair

Graduate Theses and Dissertations

As digital circuit design continues to evolve due to progress of semiconductor processes well into the sub 100nm range, clocked architectures face limitations in a number of cases where clockless asynchronous architectures require substantially less power, generate less noise, and produce less electromagnetic interference (EMI). This dissertation develops the Delay Insensitive Ternary Logic (DITL) asynchronous design paradigm that combines the designs aspects of similar Dual-Rail asynchronous paradigms and Boolean logic to create a single wire per bit, three voltage signaling and logic scheme.

DITL is designed at the transistor level using multi-threshold CMOS and carbon nanotube (CNT) FETs to develop …