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First Principle Calculations of the Structure and Electronic Properties of Pentacene Based Organic and ZnO Based Inorganic Semiconducting Materials

Description: In this thesis, I utilize first principles density functional theory (DFT) based calculations to investigate the structure and electronic properties including charge transfer behaviors and work function of two types of materials: pentacene based organic semiconductors and ZnO transparent conducting oxides, with an aim to search for high mobility n-type organic semiconductors and fine tuning work functions of ZnO through surface modifications. Based on DFT calculations of numerous structure combinations, I proposed a pentacene and perfluoro-pentacene alternating hybrid structures as a new type of n-type semiconductor. Based on the DFT calculations and Marcus charge transfer theory analysis, the new structure has high charge mobility and can be a promising new n-type organic semiconductor material. DFT calculations have been used to systematically investigate the effect of surface organic absorbate and surface defects on the work function of ZnO. It was found that increasing surface coverage of organic groups and decreasing surface defects lead to decrease of work functions, in excellent agreement with experimental results. First principles based calculations thus can greatly contribute to the investigating and designing of new electronic materials.
Date: May 2012
Creator: Li, Yun
Partner: UNT Libraries

Monitoring and Increasing Goal Related Instruction and Engagement in Groups of Children with Autism

Description: A high rate of instructional engagement is important to maximize progress in early intensive behavioral interventions (EIBI). Teachers responsible for eliciting instructional engagement may need additional support to maintain high rates of engagement. Literature suggests that goal setting and feedback is effective in increasing performance. the purpose of this study was to evaluate whether goal setting and group feedback would increase engagement in instructional activities related to the children’s goals. Results indicate that goal setting and group feedback was successful in increasing engagement in instructional activities. the results are discussed in the context of engagement, staff performance, group contingencies and performance feedback.
Date: May 2012
Creator: Rossi, Kathleen Anne
Partner: UNT Libraries

Evaluation of Fine Particulate Matter Pollution Sources Affecting Dallas, Texas

Description: Dallas is the third largest growing industrialized city in the state of Texas. the prevailing air quality here is highly influenced by the industrialization and particulate matter 2.5µm (PM2.5) has been found to be one of the main pollutants in this region. Exposure to PM2.5 in elevated levels could cause respiratory problems and other health issues, some of which could be fatal. the current study dealt with the quantification and analysis of the sources of emission of PM2.5 and an emission inventory for PM2.5 was assessed. 24-hour average samples of PM2.5 were collected at two monitoring sites under the Texas Commission on Environmental Quality (TCEQ) in Dallas, Dallas convention Centre (CAMS 312) and Dallas Hinton sites (CAMS 60). the data was collected from January 2003 to December 2009 and by using two positive matrix models PMF 2 and EPA PMF the PM2.5 source were identified. 9 sources were identified from CAMS 312 of which secondary sulfate (31% by PMF2 and 26% by EPA PMF) was found to be one of the major sources. Data from CAMS 60 enabled the identification of 8 sources by PMF2 and 9 by EPA PMF. These data also confirmed secondary sulfate (35% by PMF2 and 34% by EPA PMF) as the major source. to substantiate the sources identified, conditional probability function (CPF) was used. the influence of long range transport pollutants such as biomass burns from Mexico and Central America was found to be influencing the region of study and was assessed with the help of potential source contribution function (PSCF) analysis. Weekend/weekday and seasonal analyses were useful in understanding the behavioral pattern of pollutants. Also an inter comparison of the model results were performed and EPA PMF results was found to be more robust and accurate than PMF 2 results.
Date: May 2012
Creator: Puthenparampil Koruth, Joseph
Partner: UNT Libraries

“The Way It Goes”: Stories

Description: This collection of short stories attempts to examine the role of a changing and often indifferent world has in the way various characters achieve maturity. Though the past is not always obvious in each story, each protagonist is characterized as holding onto some aspect of his or her past life in a way that is detrimental to their growing as human beings. the stories attempt to portray the indifference of the world as it moves forward to the plight of these characters, and to portray the manner in which they each come to terms with such a world and with their own lives.
Date: May 2012
Creator: Wood, Joshua
Partner: UNT Libraries

Implementation of Wireless Communications on Gnu Radio

Description: This thesis investigates the design and implementation of wireless communication system over the GNU Radio. Wireless applications are on the rise with advent of new devices, therefore there is a need to transfer the hardware complexity to software. This development enables software radio function with minimum hardware dependency. the purpose of this thesis is to design a system that will transmit compressed data via Software Defined Radio (SDR). Some parameters such as modulation scheme, bit rate can be changed to achieve the desired quality of service. in this thesis GNU (GNU’s not unix) radio is used while the hardware structure is Universal Software Radio Peripheral (USRP). in order to accomplish the goal, a compression technique called H264 (MPEG_4) encoding is applied for converting data into compressed format. the encoder was implemented in C++ to get compressed data. After encoding, the transmitter reads the compressed data and starts modulation. After modulation, the transmitter put the packets into USRP and sends it to the receiver. Once packets are received they are demodulated and then decoded to recover the original data.
Date: May 2012
Creator: Njoki, Simon M.
Partner: UNT Libraries

Western Media Attitudes Toward an Immigrant of Color Sex Crime Victim: Case Study: the DSK Case

Description: About 30 million women in the U.S. are estimated to be victims of sex crimes in their lifetimes. However, sex crimes, especially those committed against immigrants are the least reported crime in the country. Some sex crime victims say the fear of media criticism discourages them from reporting the crime. in May 2011, an African maid working at a New York hotel accused Dominique Strauss-Kahn, the former director of the International Monetary Fund, of sexually assaulting her. This qualitative content analysis examined the coverage of the DSK case, by three leading international newspapers: the New York Times, the Guardian and Le Monde. Findings suggest that Strauss-Kahn received more favorable coverage than Diallo. Frames identified in the coverage include the importance of status/prominence, race, culture differences, victim-blaming, male privilege, socioeconomic differences and focus on appearance. the study recommends that news organizations avoid judgmental coverage of sex crimes and consider identifying victims by allowing them to tell their side of the story.
Date: May 2012
Creator: Mumah, Jenny
Partner: UNT Libraries

Performance Rights in Sound Recordings: the Impact of the Performance Rights Act on Radio, Records, and Performing Artists

Description: The original works of copyright holders included tangible creations, as music written on a page, thereby, extending copyright protection to songwriters and music publishers. Until 1995, absent from U.S. copyright law was protection for copyright owners of intangible sound recordings. the Performance Rights Act (PRA) seeks to amend the US copyright law in order to grant copyright holders of sound recordings the right to performance royalties from terrestrial broadcast radio. If passed, the legislation would be unprecedented in the United States. the PRA has implications for broadcast radio, record labels, and performing artists. This study includes historical and legal perspective of previous attempts at legislation of this nature and predicts outcomes of current legislation.
Date: May 2012
Creator: Wright-Harmon, Joy
Partner: UNT Libraries

The Effects of Textual Fluency on the Rate of Acquisition and Application of Intraverbal Relations

Description: Intraverbal behavior governs core elements of academic and intellectual behavior. These intraverbal relations can be explicitly taught when an individual is prompted to provide an appropriate response with pictures, text, or other stimuli following a verbal stimulus. It is possible that a focus on fluency of the target repertoires may lead to more conclusive data. the current study assessed the effects of precision teaching based instruction for component textual repertoires on the acquisition of intraverbal relations. Specifically, this study compared the effectiveness of two textual prompting procedures (with and without fluency-based instruction) on the acquisition and application of intraverbal relations using time-delay and a carefully controlled set of intraverbal stimuli. Results indicate that the use of textual prompts and an errorless time-delay transfer of stimulus control procedure were effective strategies for teaching intraverbal responses regardless of the inclusion of fluency-based instruction.
Date: May 2012
Creator: Shrontz, Rachael E.
Partner: UNT Libraries

Examining the Shade/flood Tolerance Tradeoff Hypothesis in Bottomland Herbs Through Field Study and Experimentation

Description: While there is growing evidence that shade/flood tolerance tradeoffs may be important in distributions of bottomland hardwood trees and indications that they should apply to herbs, no studies have definitively explored this possibility. Four years of field data following historic flooding were supplemented with a greenhouse experiment designed to identify interactions congruent with tradeoffs. Fifteen bottomland species were grown in two levels of water availability and three levels of shade over 10 weeks. Results indicate responses of Fimbristylis vahlii and Ammannia robusta are consistent with tradeoffs. Modification of classical allometric responses to shade by substrate saturation indicates a potential mechanism for the tradeoff in A. robusta. Responses indicating potential for increased susceptibility to physical flooding disturbance are also discussed.
Date: May 2012
Creator: Sloop, Jordan
Partner: UNT Libraries

“Valentine’s Day” and Other Works

Description: The following collection includes three short stories and two essays compiled with a critical preface. “Valentine’s Day” explores the limits of friendship and love in various situations including, two road trips (one fictional and one factual), pet ownership, and the impersonations of Frank Sinatra.
Date: May 2012
Creator: Thornburg, Chrissie
Partner: UNT Libraries

“Almost Astronauts”: Short Stories

Description: In this collection of short stories, I abduct experiences from my own life and take them on an imaginative journey. I experiment with elements of structure and point of view, often incorporating the magical or surreal to amplify the narrator’s internal landscape. As demonstrated in the title story, “Almost Astronauts,” these stories all deal with a sudden and sometimes destructive shift in the narrator’s perspective.
Date: May 2012
Creator: Miller, Laura I.
Partner: UNT Libraries

Impact of Congruence Between Self-disclosed Personal Information and Review on Source Credibility in Online Travel Reviews

Description: This experimental study examined the source-message congruence effect on source credibility by manipulating the congruence of the reviewer’s profile information (travel interest, geographical location) with no changes in the review content. the congruence effect was found to influence perceptions of the reviewer’s expertise in a travel interest. This finding suggests that revealing the reviewer’s travel interest can assist the credibility assessment of travel reviewers-particularly in terms of expertise-within the category of a travel interest. the refined classification of travel reviewers based on their travel interests can improve their usefulness as information sources for prospective travelers’ information searches. These attributes can further be employed as search cues if embedded in the reviewer’s profile.
Date: May 2012
Creator: Park, Hee Lye
Partner: UNT Libraries

Jiggs

Description: Jiggs is a documentary that explores how Jiggs Gaffney serves despite his mental disability. By observing Jiggs’ involvement at Pine Cove Christian Camps, and revealing his past, the documentary shows how anyone can be used for a greater good, and reveals how God can be served and glorified by anyone, no matter the individual circumstances.
Date: May 2012
Creator: Sosa, Mario
Partner: UNT Libraries

Investigating Realistic Scenarios of Biodiversity Loss on Ecosystem Functioning: Extirpation of Rare Species and Food Web Collapse in Tropical Floodplain Lagoons

Description: This thesis investigates the influence of nonrandom species loss on the structure and functioning of trophic floodplain lagoons. Two experiments were conducted based on different realistic scenarios of biodiversity loss using multitrophic fish assemblages derived from long-term survey data. Loss of fish diversity influenced overall ecosystem multifunctionality of these lagoons through complex multitrophic interactions throughout the aquatic food web. These results indicate that biodiversity loss from diverse multitrophic ecosystems can influence ecosystem structure and function and likely deviate from simplified food chain dynamics or patterns that emerged from single trophic level studies.
Date: May 2012
Creator: Pendleton, Richard McCall
Partner: UNT Libraries

Implementing a Physical Activity Centered Education Program for Individuals with Brain Injury

Description: Research has shown that health promotion programs (HPP) that incorporate education about physical activity (PA) are one mode of rehabilitation that can improve the health of individuals with disabilities. However, education-based PA curriculum is not included in the rehabilitation program for individuals with a brain injury, indicating a gap in services provided. Consequently, the purpose of this study was to create and deliver a physical activity centered education (PACE) program that supplemented the existing rehabilitation program for brain injury. PACE consists of an 8-week (16 session) program aimed to (1) increase self-efficacy for being physically active of PACE program participants, (2) increase PA stage of change in PACE program participants or the maintenance of adequate level of PA, and (3) improve the rehabilitation outcomes (i.e., abilities, participation, adjustment) of PACE program participants. Based on previous research, it is hypothesized that participation in PACE will result in (1A) increased self-efficacy for PA, (1B) greater self-efficacy for PA than the standard of care group, (2A) increased readiness to be physically active, (2B) greater readiness to change their PA behavior than the standard of care group, (3A) improved rehabilitation outcomes, and (3B) greater rehabilitation outcomes than the standard of care group. the PACE program resulted in: (1) an average increase of 19.36% in participants’ PA self-efficacy (effect size [ES] = 0.37), (2) 15 of the 22 PACE participants (68.18%) reported readiness to engage in regular PA , and (3) an increase in rehabilitation outcomes (i.e., abilities, adjustment, and participation)In conclusion, the PACE program can improve PA self-efficacy, readiness for regular PA behavior, and improved short-term rehabilitation outcomes.
Date: May 2012
Creator: Woolsey, Anne-Lorraine T.
Partner: UNT Libraries

Detection of Mercury Among Avian Trophic Levels at Caddo Lake and Lake Lewisville, TX

Description: Mercury (Hg) is a globally distributed toxicant that has been shown to have negative effects on birds. in the United States, avian taxa have been shown to possess high Hg concentrations in the northeast, Great Lakes and Everglades ecosystems; however, few studies have measured avian Hg concentrations in other geographic regions. Previous studies have documented high Hg concentrations in multiple organisms in east Texas, but birds were not included in these studies. the main objective of the present study was to quantify Hg concentrations in birds in differing trophic levels at Caddo Lake and Lake Lewisville, TX. Results suggest that Hg concentrations may be high enough to negatively impact some bird taxa, particularly those at high trophic levels, residing at both Caddo Lake and Lake Lewisville.
Date: May 2012
Creator: Schulwitz, Sarah Elizabeth
Partner: UNT Libraries

Experimental Determination of L, Ostwald Solubility Solute Descriptor for Illegal Drugs By Gas Chromatography and Analysis By the Abraham Model

Description: The experiment successfully established the mathematical correlations between the logarithm of retention time of illegal drugs with GC system and the solute descriptor L from the Abraham model. the experiment used the method of Gas Chromatography to analyze the samples of illegal drugs and obtain the retention time of each one. Using the Abraham model to calculate and analyze the sorption coefficient of illegal drugs is an effective way to estimate the drugs. Comparison of the experimental data and calculated data shows that the Abraham linear free energy relationship (LFER) model predicts retention behavior reasonably well for most compounds. It can calculate the solute descriptors of illegal drugs from the retention time of GC system. However, the illegal drugs chosen for this experiment were not all ideal for GC analysis. HPLC is the optimal instrument and will be used for future work. HPLC analysis of the illegal drug compounds will allow for the determination of all the solute descriptors allowing one to predict the illegal drugs behavior in various Abraham biological and medical equations. the results can be applied to predict the properties in biological and medical research which the data is difficult to measure. the Abraham model will predict more accurate results by increasing the samples with effective functional groups.
Date: May 2012
Creator: Wang, Zhouxing
Partner: UNT Libraries

Electrochemical Depostion of Bismuth on Ruthenium and Ruthenium Oxide Surfaces

Description: Cyclic voltammetry experiments were performed to compare the electrodeposition characteristics of bismuth on ruthenium. Two types of electrodes were used for comparison: a Ru shot electrode (polycrystalline) and a thin film of radio-frequency sputtered Ru on a Ti/Si(100) support. Experiments were performed in 1mM Bi(NO3)3/0.5M H2SO4 with switching potentials between -0.25 and 0.55V (vs. KCl sat. Ag/AgCl) and a 20mV/s scan rate. Grazing incidence x-ray diffraction (GIXRD) determined the freshly prepared thin film electrode was hexagonally close-packed. After thermally oxidizing at 600°C for 20 minutes, the thin film adopts the tetragonal structure consistent with RuO2. a hydrated oxide film (RuOx?(H2O)y) was made by holding 1.3V on the surface of the film in H2SO4 for 60 seconds and was determined to be amorphous. Underpotential deposition of Bi was observed on the metallic surfaces and the electrochemically oxidized surface; it was not observed on the thermal oxide.
Date: May 2012
Creator: Taylor, Daniel M.
Partner: UNT Libraries

The Natural Learning Process and Its Implications for Trombone Pedagogy

Description: This thesis considers the natural learning process as defined by Timothy Gallwey and Daniel Kohut. This learning theory is examined and applied to trombone pedagogy while also considering physiological attributes to trombone performance. a brief synopsis of the history and lineage of the trombone is considered in order to understand the current setting of the trombone medium.
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Date: May 2012
Creator: Reider, Shane Robert
Partner: UNT Libraries

My Land, My Life

Description: My Land, My Life is a documentary film about the woman, Jo Angela Lamb, who lives and works on Frying Pan Ranch in Texas Panhandle. the film explores the complexity of a ranch woman's experience that breaks the spell of the stereotyped image of American cowgirls. It also reflects on women ranchers’ relationship with their family members and their relationship with the land.
Date: May 2012
Creator: Zhang, Mingyun
Partner: UNT Libraries

Social Networking: the Benefits of Twitter for Music Fans and Consumers

Description: Due to the evolution of new media technologies, social networking websites have become major avenues for online media consumption. Twitter is one of many proven beneficial for online users. It is utilized for many different reasons, one of which includes music. It is then necessary to know how beneficial Twitter is for music fans and consumers. This study attempts to analyze the benefits of Twitter for music fans and consumers. Using an online survey, different gratification items are measured. Results reveal that some music fans and consumers do use Twitter for music purposes and that there is a statistically significant difference in terms of gratifications between those who use Twitter for music purposes and those who do not.
Date: May 2012
Creator: Perrilliat, Jessica A.
Partner: UNT Libraries

Alternative Complementation in Partially Schematic Constructions: a Quantitative Corpus-based Examination of COME to V2 and GET to V2

Description: This paper examines two English polyverbal constructions, COME to V2 and GET to V2, as exemplified in Examples 1 and 2, respectively. (1) the senator came to know thousands of his constituents (2) Little Johnny got to eat ice cream after every little league game. Previous studies considered these types of constructions (though come and get as used here have not been sufficiently studied) as belonging to a special class of complement constructions, in which the infinitive is regarded as instantiating a separate, subordinate predication from that of the “matrix” or leftward finite verb. These constructions, however, exhibit systematic deviation from the various criteria proposed in previous research. This study uses the American National Corpus to investigate the statistical propensities of the target phenomena via lexico-syntactic (collostructional analysis) and morpho-syntactic (binary logistic regression) features, as captured through the lens of construction grammar.
Date: May 2012
Creator: Lester, Nicholas A.
Partner: UNT Libraries

Baseband Noise Suppression in Ofdm Using Kalman Filter

Description: As the technology is advances the reduced size of hardware gives rise to an additive 1/f baseband noise. This additive 1/f noise is a system noise generated due to miniaturization of hardware and affects the lower frequencies. Though 1/f noise does not show much effect in wide band channels because of its nature to affect only certain frequencies, 1/f noise becomes a prominent in OFDM communication systems where narrow band channels are used. in this thesis, I study the effects of 1/f noise on the OFDM systems and implement algorithms for estimation and suppression of the noise using Kalman filter. Suppression of the noise is achieved by subtracting the estimated noise from the received noise. I show that the performance of the system is considerably improved by applying the 1/f noise suppression.
Date: May 2012
Creator: Rodda, Lasya
Partner: UNT Libraries

The Portuguese Expeditionary Corps in World War I: From Inception to Destruction, 1914-1918

Description: The Portuguese Expeditionary Force fought in the trenches of northern France from April 1917 to April 1918. on 9 April 1918 the sledgehammer blow of Operation Georgette fell upon the exhausted Portuguese troops. British accounts of the Portuguese Corps’ participation in combat on the Western Front are terse. Many are dismissive. in fact, Portuguese units experienced heavy combat and successfully held their ground against all attacks. Regarding Georgette, the standard British narrative holds that most of the Portuguese soldiers threw their weapons aside and ran. the account is incontrovertibly false. Most of the Portuguese combat troops held their ground against the German assault. This thesis details the history of the Portuguese Expeditionary Force.
Date: May 2012
Creator: Pyles, Jesse
Partner: UNT Libraries