UNT Theses and Dissertations - Browse

ABOUT BROWSE FEED
Note: All results matching your query require you to be a member of the UNT Community (you must be on campus or login with university credentials for access).

9-Lipoxygenase Oxylipin Pathway in Plant Response to Biotic Stress

Description: The activity of plant 9-lipoxygenases (LOXs) influences the outcome of Arabidopsis thaliana interaction with pathogen and insects. Evidence provided here indicates that in Arabidopsis, 9-LOXs facilitate infestation by Myzus persicae, commonly known as the green peach aphid (GPA), a sap-sucking insect, and infection by the fungal pathogen Fusarium graminearum. in comparison to the wild-type plant, lox5 mutants, which are deficient in a 9-lipoxygenase, GPA population was smaller and the insect spent less time feeding from sieve elements and xylem, thus resulting in reduced water content and fecundity of GPA. LOX5 expression is induced rapidly in roots of GPA-infested plants. This increase in LOX5 expression is paralleled by an increase in LOX5-synthesized oxylipins in the root and petiole exudates of GPA-infested plants. Micrografting experiments demonstrated that GPA population size was smaller on plants in which the roots were of the lox5 mutant genotype. Exogenous treatment of lox5 mutant roots with 9-hydroxyoctadecanoic acid restored water content and population size of GPA on lox5 mutants. Together, these results suggest that LOX5 genotype in roots is critical for facilitating insect infestation of Arabidopsis. in Arabidopsis, 9-LOX function is also required for facilitating infection by F. graminearum, which is a leading cause of Fusarium head blight (FHB) disease in wheat and other small grain crops. Loss of LOX1 and LOX5 function resulted in enhanced resistance to F. graminearum infection. Similarly in wheat, RNA interference mediated silencing of the 9-LOX homolog TaLpx1, resulted in enhanced resistance to F. graminearum. Experiments in Arabidopsis indicate that 9-LOXs promote susceptibility to this fungus by suppressing the activation of salicylic acid-mediated defense responses that are important for basal resistance to this fungus. the lox1 and lox5 mutants were also compromised for systemic acquired resistance (SAR), an inducible defense mechanism that is systemically activated throughout a plant in response to a ...
Date: May 2012
Creator: Nalam, Vamsi J.
Partner: UNT Libraries

The 50,000 Watt Blowtorch of the Great Southwest: The History of WBAP

Description: This paper looks at the history of WBAP while examining how programming has changed from 1922-2014 and how WBAPs audience helped shape programming at the station. This paper reveals four formatting changes throughout the stations history and provides in-depth statistical analysis of how WBAPs audience changed during the stations 90 plus years of existence.
Date: December 2016
Creator: Dixon, Chad M
Partner: UNT Libraries

161 Glass: Site Specific Music in an Artistic Context

Description: The composition 161 Glass is a 17-minute musical work with percussion, wind and brass instruments in which the intersection of mid-century architecture, and the art and culture of a dynamic city are inextricably linked. Through this paper, I explore the process of composing a musical work in relationship to the significance of site specific context. The paper begins by defining the concept of site specific art works; then reviews the discourse of the intersection of art, music and architecture. I then delve into the cultural and geographic context surrounding this project from the modern era through the present, and how those perspectives apply to the building and my piece. I reveal how the composition relates the musical ideas to the site. Finally, I describe the collaborative process between myself, the musicians and the Dallas Contemporary staff.
Date: May 2010
Creator: Rusnak, Christina S.
Partner: UNT Libraries

A 018μm Cmos Transmitter for Ecg Signals

Description: Electrocardiography (ECG) signal transmitter is the device used to transmit the electrical signals of the heart to the remote machine. These electrical signals are ECG signals caused due to electrical activities in the heart. ECG signals have very low amplitude and frequency; hence amplification of the signals is needed to strengthen the signal. Conversion of the amplified signal into digital information and transmitting that information without losing any data is the key. This information is further used in monitoring the heart.
Date: December 2013
Creator: Kakarna, Tejaswi
Partner: UNT Libraries

The 1896 Vienna Tonkünstler-verein Competition: the Three Award-winning Works and Seven Anonymous Submissions with Clarinet

Description: The Vienna Tonkünstler-Verein (1885-1929) was established for the sole purpose of providing extensive support to the music and musicians of Vienna. The society became renowned in Vienna for its outstanding performances of chamber music and counted among its members many of the city’s foremost musicians and composers. Johannes Brahms had a significant influence on the society as its honorary president and assisted in establishing its composition competitions, aimed at promoting and reviving under-developed chamber genres. Of particular interest to clarinetists is the Verein’s competition of 1896, which aspired to promote chamber music literature for wind instruments. Brahms’s recently completed chamber works for clarinet were clearly influential in fin-de-siècle Vienna; for of the twelve works chosen as finalists in the competition, ten included the clarinet in the chamber combination.The purpose of this document is to provide an English-language history of the Vienna Tonkünstler-Verein and a thorough account of its1896 competition based on my study of the society’s annual reports. In addition, this document will provide the first published account of the anonymous submissions for the 1896 competition. It is my hope that this paper will serve as a springboard for future endeavors aimed at uncovering the identities of the anonymous finalists for this competition.
Date: August 2014
Creator: Harrell, Andrea
Partner: UNT Libraries

2D and 3D Fabrication Devices: Can They Improve Spatial Reasoning Skills in Children?

Description: The purpose of this study is to evaluate the potential benefit of two hours of activities involving 2D and 3D fabricators on the spatial reasoning skills of children in Grades 4 and 5, ages 9 to 10, from a private school in Southeast Texas. Can the introduction to hands-on activities with products created with these devices and learning about how these devices operate improve spatial reasoning skills? The research also evaluates the use of the Shapes Test as a valid measure of the spatial reasoning skills of children. The Cube Design and Spatial Memory subtests of the UNIT (Universal Nonverbal Intelligence Tests) were used for evaluating the spatial reasoning skills of the participants, based on their respected validity, along with a Shapes Test that is in development. Discussion regarding gender, language, and experiential theories of spatial reasoning skill development are included in the literature review.
Date: August 2016
Creator: Zimmerman, Ellen L
Partner: UNT Libraries

3D Reconstruction Using Lidar and Visual Images

Description: In this research, multi-perspective image registration using LiDAR and visual images was considered. 2D-3D image registration is a difficult task because it requires the extraction of different semantic features from each modality. This problem is solved in three parts. The first step involves detection and extraction of common features from each of the data sets. The second step consists of associating the common features between two different modalities. Traditional methods use lines or orthogonal corners as common features. The third step consists of building the projection matrix. Many existing methods use global positing system (GPS) or inertial navigation system (INS) for an initial estimate of the camera pose. However, the approach discussed herein does not use GPS, INS, or any such devices for initial estimate; hence the model can be used in places like the lunar surface or Mars where GPS or INS are not available. A variation of the method is also described, which does not require strong features from both images but rather uses intensity gradients in the image. This can be useful when one image does not have strong features (such as lines) or there are too many extraneous features.
Date: December 2012
Creator: Duraisamy, Prakash
Partner: UNT Libraries

3GPP Long Term Evolution LTE Scheduling

Description: Future generation cellular networks are expected to deliver an omnipresent broadband access network for an endlessly increasing number of subscribers. Long term Evolution (LTE) represents a significant milestone towards wireless networks known as 4G cellular networks. A key feature of LTE is the implementation of enhanced Radio Resource Management (RRM) mechanism to improve the system performance. The structure of LTE networks was simplified by diminishing the number of the nodes of the core network. Also, the design of the radio protocol architecture is quite unique. In order to achieve high data rate in LTE, 3rd Generation Partnership Project (3GPP) has selected Orthogonal Frequency Division Multiplexing (OFDM) as an appropriate scheme in terms of downlinks. However, the proper scheme for an uplink is the Single-Carrier Frequency Domain Multiple Access due to the peak-to-average-power-ratio (PAPR) constraint. LTE packet scheduling plays a primary role as part of RRM to improve the system’s data rate as well as supporting various QoS requirements of mobile services. The major function of the LTE packet scheduler is to assign Physical Resource Blocks (PRBs) to mobile User Equipment (UE). In our work, we formed a proposed packet scheduler algorithm. The proposed scheduler algorithm acts based on the number of UEs attached to the eNodeB. To evaluate the proposed scheduler algorithm, we assumed two different scenarios based on a number of UEs. When the number of UE is lower than the number of PRBs, the UEs with highest Channel Quality Indicator (CQI) will be assigned PRBs. Otherwise, the scheduler will assign PRBs based on a given proportional fairness metric. The eNodeB’s throughput is increased when the proposed algorithm was implemented.
Date: December 2013
Creator: Alotaibi, Sultan
Partner: UNT Libraries

Ability of Offenders with Psychopathic Traits to Simulate Cognitive and Affective Empathy

Description: The accurate assessment of psychopathy constitutes a critical component of forensic assessments addressing offender populations. Among the core characteristics of psychopathy, the interpersonal component of deception and empathic deficits are prominently observed in offenders with psychopathic traits. Given the negative consequences of being classified as a psychopath, offenders may be likely to minimize their psychopathic traits. In particular, no research has investigated whether offenders with psychopathic traits are able to simulate empathy in an effort to mask their cognitive or affective empathy deficits (e.g., lack of remorse about offenses). The present study aims to contribute to the literature with regard to the simulation of empathy. Using a mixed between- and within-subjects design, 81 male detainees were placed into (a) a low psychopathy group, (b) a moderate psychopathy group, or (c) a high psychopathy group based on the Psychopathy Checklist – Revised. For the within-subjects component, all offenders answered empathy questionnaires under genuine and simulation conditions. Results indicate the sample possessed cognitive empathy, but did not display affective empathy under genuine instructions. Under simulation instructions, participants significantly increased their scores on several empathy measures. The implications of simulated empathy and comparisons between groups regarding simulation abilities are discussed.
Date: August 2013
Creator: Robinson, Emily V.
Partner: UNT Libraries

Absorptive Capacity: An Empirical Examination of the Phenomenon and Relationships with Firm Capabilities

Description: The field of strategic management addresses challenges that firms encounter in an attempt to remain competitive. The ability to explain variation in firm success through examination of knowledge flows has become a prominent focus of research in the strategic management literature. Specifically, researchers have sought to further examine how firms convert knowledge, a phenomenon conceptualized as absorptive capacity. Absorptive capacity is the firm’s ability to acquire, assimilate, transform, and exploit knowledge. Few studies have captured the richness and multi-dimensionality of absorptive capacity, and it remains to be understood how the dimensions of the phenomenon convert knowledge. Furthermore, how absorptive capacity influences the firm remains to be understood. To address these research gaps, this dissertation seeks to (1) determine how absorptive capacity converts knowledge, and (2) determine how absorptive capacity influences firm capabilities. The research questions are investigated using structural modeling techniques to analyze data collected from software-industry firms. The findings offer contributions to the absorptive capacity and capability literatures. For example, absorptive capacity is hypothesized to consist of complex relationships among its internal dimensions. However, findings of this study suggest the relationships among the dimensions are linear in nature. This finding is in line with the theoretical foundations of and early literature on absorptive capacity but contrary to recent conceptualizations, which suggests relationships among the dimensions are more closely related to the theoretical origins of absorptive capacity. Additionally, to examine how absorptive capacity influences the firm, a capability-based perspective is used to hypothesize the influence of absorptive capacity on firm capabilities. Findings suggest absorptive capacity positively influences each dimension of firm capabilities (e.g., operational, customer, and innovation capabilities); thus, absorptive capacity influences the firm by altering firm capabilities. Given the richness of the findings, numerous fields are likely to benefit from this investigation. Through an examination of absorptive capacity and ...
Date: May 2012
Creator: Daspit, Josh
Partner: UNT Libraries

Academic Advising Professional Characteristics and Standards: Do Academic Advisors Follow Recognized Professional Standards in Their Work?

Description: There were two main purposes of this quantitative study. The first purpose was to identify characteristics associated with the selected sample of academic advisors that comprise study. Secondly, the study sought to determine how well work related activities of a selected population of academic advisors correlate with professional characteristics constructs and professional standards constructs of academic advising as a profession. The study used Habley’s (1986) characteristics of a profession to derive the studies professional characteristic construct, education activities, research activities, and professional development activities as it relates to a selected group of academic advisors work related activities. The studies professional standards construct was derived from five Council for the Advancement of Standards (CAS) professional standards for academic as it relates to a selected group of academic advisors work related activities. The study of 78 out of 210 identified full-time academic advisors at two-and four-year public colleges and universities in the North Texas Region utilized a multidimensional researcher-developed Web survey instrument designed to measure professional standards and characteristic within the field of academic advising. Study results reinforced current criticism of research and education activities within the field of academic advising showing that the lack of scholarly research and education activities among academic advisors decreases significantly their efforts towards professionalization. Also, professional standards construct results suggest that the utilization of CAS standards for academic advising as an evaluation tool may enhance an academic advisor’s knowledge of professional standards within the field.
Date: May 2014
Creator: Shelton, Kiesha R.
Partner: UNT Libraries

The Academic and Athletic Experiences of African-american Males in a Division I (Fbs) Football Program

Description: This study investigated the academic and athletic experiences of African-American males in a Division I football bowl subdivision football program. Critical race theory, identity development model, and social learning model were the theoretical frameworks used as the critical lenses in a qualitative design to examine the participants. The participants’ responses were analyzed and interpreted using thematic analysis. A qualitative research design, which included individual interviews with 10 second year African-American male football players, was used to address this research problem. The goal was to bring together both the psychological and sociological perspectives and to challenge participants to candidly describe their academic and athletic experiences and attitudes toward obtaining an undergraduate degree. Four themes were determined in the data analysis: differential treatment and determining oneself, time management, relationships, and career aspirations. In relation to the theoretical frameworks, the development of self-confidence and knowledge of balancing their academic and athletic schedules was critical for all participants. The sense of feeling different and challenged because of the differences in culture and experience was evident. From this study, university and collegiate athletics administrators may better understand the backgrounds, challenges, and learning needs of this population. As a result, higher education personnel may improve the services they provide these young men in hopes of educating and developing whole persons—physically, emotionally, intellectually, socially, and spiritually—to become well-rounded and functional in contemporary society.
Date: December 2013
Creator: Salinas, Silvia M.
Partner: UNT Libraries

Academic Progress Scores to Predict Performance on a State Assessment

Description: This quantitative study examined seventh-grade reading scores to determine the extent to which certain demographic variables (race/ethnicity, gender, socioeconomic status) explain and MAP reading scores predict reading scores on the State of Texas Assessment of Academic Readiness (STAAR) in a selected northeast Texas public school. Standardized assessments only compare the relative performance of an individual student to other groups of students using scaled scores, which can vary from year to year and from state to state. With the advent of computer adaptive testing, this study provides information on the predictive validity of benchmark assessments. Specifically, this study looked for predictive evidence that indicates how accurately test data can predict criterion scores. Findings revealed, through a multiple regression analysis, that the fall MAP Rasch Unit (RIT) scores predicted the STAAR scale scores. Using SPSS version 22, the data were entered and analyzed in a multiple regression model to determine the presence of a statistical trend or lack thereof. Demographic data and MAP scores were entered into the regression model to examine the predictive validity of the MAP assessment in determining student performance on the STAAR seventh-grade state-mandated reading assessment. The statistical analysis revealed that MAP RIT scores explain a significant variance related to seventh-grade STAAR reading scale scores. There is a vital need for tools that improve a student's academic development and MAP assessments have been found to predict performance on state-mandated assessments.
Date: December 2016
Creator: Curry, David Mitchell
Partner: UNT Libraries

Academic Reading Online: Digital Reading Strategies of Graduate-level English Language Learners

Description: English language learners (ELLs) face many linguistic and cultural challenges in their attempts to succeed academically. They encounter complex academic text, which is increasingly presented online. Although some research has addressed the challenges that university-level ELLs face when reading online texts, almost all of this prior work has focused on undergraduates. The purpose of the current study was to investigate the reading strategies employed by graduate-level ELLs when reading an academic English text online. Participating in the study were four foreign-born doctoral students from different first-language backgrounds—Arabic, Korean, Urdu, and Vietnamese—and the focus was on commonalities as well as differences among them. All four were enrolled in the same doctoral-level course, which included the reading of a specific online academic article as a course requirement. When reading this text individually, each student participated in a think-aloud procedure, followed by post-reading and discourse-based interviews. Analyses included unitizing data from the think-aloud protocols, coding units for strategies employed, and considering related interview commentary and classroom contributions. In their reading, these students made major use of problem-solving strategies, especially reading segments aloud and questioning. They also employed evaluative strategies as well as metacognitive strategies, which included affirming their understanding or indicating lack of understanding. With respect to global strategies, all made use of the article’s abstract and used the cursor to scroll forward to preview the article. In contrast to previous research with undergraduates, these students made little use of support strategies that involved translation websites. Instead, their major support strategies were navigating to web-based tools, particularly online encyclopedias in English. Despite prior theory and research suggesting the importance of sociorhetorical strategies in academic reading, only one student directed much attention to the authors of the article and to authorial intent. Although all four participants were students in the same doctoral course and ...
Date: May 2015
Creator: Knezek, Lois Ann
Partner: UNT Libraries

Academic Self-efficacy of Adult First-generation Students Enrolled in Online Undergraduate Courses

Description: This study examined differences between adult first-generation (AFG) and adult-continuing generation (ACG) students’ academic self-efficacy with regard to the online courses in which they were currently enrolled. The study used an online survey methodology to collect self-reported quantitative data from 1,768 undergraduate students enrolled in an online course at a mid-sized, four-year public university in the southwestern United States; 325 cases were usable for the study. The t-tests revealed no statistically significant differences between the academic self-efficacy of the AFG and ACG students. Parents’ level of educational attainment was unrelated to adult students’ academic self-efficacy with online courses. Ordinary least-squares analysis was used to evaluate student characteristics that might be associated with academic self-efficacy in the online environment. A combination of gender, GPA, age, race/ethnicity (White, Black, Hispanic, and other), and number of previous online courses predicted a statistically significant 12% of the variance in academic self-efficacy in an online environment (p < .001). Age (p < .001) and self-efficacy were positively correlated, meaning that adult students reported greater academic self-efficacy than did younger students; and number of previous online courses (p < .001) was also positively correlated to academic self-efficacy, indicating that students with greater experience with online courses reported a greater sense of academic self-efficacy in that environment than students who had completed fewer online courses. This study has implications of providing additional insight for higher education practitioners working with adult learners. Identifying additional factors influencing adult learners’ academic self-efficacy in an online academic environment may be useful when building effective strategies to improve online retention and completion rates for these students. Future research should examine a wider variety of variables beyond demographic characteristics. External and internal factors, along with existing theories of behaviors should be investigated to help explain adult persistence and retention online and in face-to-face ...
Date: August 2014
Creator: Jackson, Delores
Partner: UNT Libraries

Academic, Social and Emotional Functioning of College Students with Attention-Deficit/Hyperactivity Disorder (ADHD)

Description: Attention deficit/hyperactivity disorder (ADHD) is frequently associated with negative occupational, social and psychological outcomes among community samples of adults; as such, it is expected that college students with ADHD face similar struggles. The research targeting this group of individuals, however, is sparse and tempered by significant limitations. The current study aimed to address methodological limitations in the current literature by including instruments to formally diagnosis ADHD and comorbid disorders, utilizing psychometrically sound instruments and comparing functioning of college students with ADHD across gender and subtype. It was hypothesized that participants with ADHD would report lower GPAs, higher levels of emotional distress and negative relationship characteristics than participants without ADHD. It was also hypothesized that participants with ADHD-combined type (ADHD-C) would report higher levels of substance and alcohol use than participants with ADHD-predominately inattentive type (ADHD-I), and that participants with ADHD-I would report higher levels of anxiety and depression than participants with ADHD-C. Women diagnosed with ADHD were expected to report higher levels of anxiety and depression than men diagnosed with ADHD; whereas, men diagnosed with ADHD were expected to report higher levels of substance and alcohol use than women. MANOVA, ANOVA and Mann-Whitney U tests were conducted to test hypotheses. Results revealed no significant differences between the ADHD and comparison group on GPA and relationship characteristics. Participants diagnosed with ADHD did report significantly higher emotional distress than participants in the comparison group. No differences in GPA or relationship characteristics were found across ADHD subtype or gender. Overall, these findings provide evidence to suggest that college students with ADHD are functioning relatively well compared to their non-ADHD peers.
Date: August 2015
Creator: McKelvy, Tara N.
Partner: UNT Libraries

Accelerated Degree Program Faculty: Motivation to Teach

Description: Adult educators are a growing part of American higher education. Because of their increasing prominence in adult education, it is essential to understand what roles these educators play and what motivates them to remain in the profession despite poor work prospects and conditions. Research to date, however, focuses primarily on the adult learner and not the adult educator. The purpose of this qualitative, multiple-case study was to explore the role and motivation for teaching of adult educators employed as adjunct faculty in an accelerated degree program at a small, liberal arts college in the northwest United States. Purposeful sampling was used to select the five participants for the study. All participants taught in the program for more than five years and were considered to be successful in their positions by peers, students, and administrators. The study employed a preliminary demographic survey to solicit initial background data on the instructors. Other data collection included in-depth, open-ended, face-to-face interviews, document analysis, and classroom observation. The results showed that all five participants identified the following roles and assumed them in the classroom: (a) facilitator, (b) listener, (c) specialist, (d) guide, (e) adviser, and (f) co-learner or colleague. Further results showed that all five participants were motivated to teach in the program for reasons other than monetary compensation. Although participants shared different levels of personal commitment to the institution, they all expressed extensive commitment to teaching, their discipline, and students. Motivating factors for teaching were (a) opportunity to teach part time, (b) love for the subject, (c) opportunity to gain more expertise in the field, (d) opportunity to grow and learn, (e) opportunity to give back, and (f) student success and growth. A major practical implication of this study is that adjunct faculty in an adult education program are motivated to teach for different ...
Date: May 2016
Creator: Grishkevich, Hanna Hults
Partner: UNT Libraries

An Accelerometer-based Gesture Recognition System for a Tactical Communications Application

Description: In modern society, computers are primarily interacted with via keyboards, touch screens, voice recognition, video analysis, and many others. For certain applications, these methods may be the most efficient interface. However, there are applications that we can conceive where a more natural interface could be convenient and connect humans and computers in a more intuitive and natural way. These applications are gesture recognition systems and range from the interpretation of sign language by a computer to virtual reality control. This Thesis proposes a gesture recognition system that primarily uses accelerometers to capture gestures from a tactical communications application. A segmentation algorithm is developed based on the accelerometer energy to segment these gestures from an input sequence. Using signal processing and machine learning techniques, the segments are reduced to mathematical features and classified with support vector machines. Experimental results show that the system achieves an overall gesture recognition accuracy of 98.9%. Additional methods, such as non-gesture recognition/suppression, are also proposed and tested.
Date: December 2015
Creator: Tidwell, Robert S., Jr.
Partner: UNT Libraries

Acceptability of Behavioral Interventions for Autism

Description: Caregivers' evaluation of evidence-based behavioral interventions may differ dependent upon the type of language used to describe the intervention. We administered a survey to 24 parents of children with autism to assess social validity measures of behavioral interventions described in one of three communication styles: technical, conversational, and conversational with intended outcome. Participants were presented with a description of two behavior-reduction and two behavior-acquisition interventions. Overall, interventions described in conversational with intended outcome style received the highest social validity ratings, while interventions described in the technical style received the lowest ratings. Moreover, behavior-acquisition interventions were rated significantly higher than behavior-reduction interventions when described in either conversational or conversational with intended outcome style. The current study supports the requirements of the Behavior Analyst Certification Board's Compliance Code that behavior analysts should inform the client/consumer of the treatment/interventions in an understandable language. Findings are also discussed in terms of verbal communities.
Date: December 2016
Creator: Fatema, Afshaan
Partner: UNT Libraries

Acceptance Theories for Behavior in Conducting Research: Instructors in the Rajabhat University System, Thailand

Description: Responding to globalization and its effects on education and research development, the Thai government decided to push all public universities to become autonomous and establish a system of quality assurances. The establishment of quality assurances has had a large impact on many Thai instructors, especially in new public universities. Thai instructors are now forced to more focus on conducting research because the number of research publications is regarded as one of the main criteria for quality universities. The purpose of this study is to investigate the key factors, at the individual and university levels, which impact on the instructors' behavior in conducting research of the full-time instructors in the faculty of Management Science from the Rajabhat Universities in Thailand. The current study will help explain how and why the instructors accept or refuse to conduct research and provide insight into the salient factors motivating the instructors to produce more research by conducting HLM. Data were collected from 694 participants at 37 institutions via a questionnaire survey. The findings revealed that there was no difference among these 37 universities on behavior in conducting research. The key factors statistically influencing behavior in conducting research of the instructors were facilitating conditions, academic degree, social influence, and usefulness as well as ease of conducting research that the instructors perceived. This study gained 46% of effect size.
Date: December 2015
Creator: Laksaniyanon, Benchamat
Partner: UNT Libraries

Acceptor-sensitizers for Nanostructured Oxide Semiconductor in Excitonic Solar Cells

Description: Organic dyes are examined in photoelectrochemical systems wherein they engage in thermal (rather than photoexcited) electron donation into metal oxide semiconductors. These studies are intended to elucidate fundamental parameters of electron transfer in photoelectrochemical cells. Development of novel methods for the structure/property tuning of electroactive dyes and the preparation of nanostructured semiconductors have also been discovered in the course of the presented work. Acceptor sensitized polymer oxide solar cell devices were assembled and the impact of the acceptor dyes were studied. The optoelectronic tuning of boron-chelated azadipyrromethene dyes has been explored by the substitution of carbon substituents in place of fluoride atoms at boron. Stability of singlet exited state and level of reduction potential of these series of aza-BODIPY coumpounds were studied in order to employ them as electron-accepting sensitizers in solid state dye sensitized solar cells.
Date: August 2014
Creator: Berhe, Seare Ahferom
Partner: UNT Libraries

Accessing the Power of Aesthetics in Human-computer Interaction

Description: In information systems design there are two schools of thought about what factors are necessary to create a successful information system. The first, conventional view holds that system performance is a key, so that efficiency characteristics such as system usability and task completion time are primary concerns of system designers. The second, emerging view holds that the visual design is also the key, so that visual interface characteristics such as visual appeal, in addition to efficiency characteristics, are critical concerns of designers. This view contends that visual design enhances system use. Thus, this work examines the effects of visual design on computer systems. Visual design exerts its influence on systems through two mechanisms: it evokes affective responses from IT users, such as arousal and pleasure and it influences individuals’ cognitive assessments of systems. Given that both affective and cognitive reactions are significant antecedents of user behaviors in the IT realm, it is no surprise that visual design plays a critical role in information system success. Human-computer-interaction literature indicates that visual aesthetics positively influences such information success factors as usability, online trust, user satisfaction, flow experience, and so on. Although academic research has introduced visual design into the Information Systems (IS) field and validated its effects, visual design is still very limited in three contexts: product aesthetics in e-commerce, mobile applications and commercial emails. This dissertation presents three studies to help fill these theoretical gaps respectively.
Date: August 2013
Creator: Chenyan, Xu
Partner: UNT Libraries

Accomplished Teachers' Instructional Decisions About Shakespeare

Description: Teachers' decisions are a powerful influence on student learning and it is important to fully document accomplished teachers' instructional decisions, as well as to investigate possible influences on those decisions. Shakespearean dramas are central to high school curricula across the U.S. and pose particular instructional challenges, therefore teachers' decisions about teaching these texts are of particular interest. There is limited empirical research, however, about these instructional decisions. Thus, the purpose of this study was to describe how four accomplished high school English teachers working on a single campus make instructional decisions about teaching a Shakespearean play. Specifically, research questions addressed teachers' decisions regarding the teaching of a Shakespearean play and various influences on those decisions (self-reports and inferences from the data). Case study methodology was used, including an inductive analysis of individual teacher interviews, classroom observations, focus group, instructional artifacts, and researcher's journal. The findings revealed that instructional activities described by these teachers addressed support for meaning-making during four stages of reading instruction: (a) before, during, and after; (b) before; (c) during; and (d) after. Comparison of these cases suggests that, although each teacher brings personal preferences and unique background knowledge to her instructional decisions, all make decisions to promote student engagement and student construction of meaning. Regarding influences on these teachers' decisions about teaching the Shakespearean play, four categories were identified: (a) response to students; (b) aspects of the text; (c) response to contextual constraints and supports; and (d) personal preferences and background experiences. Individual teacher differences are clearly a strong influence, even among this group of colleagues on the same campus. Also, two influences not reported explicitly by the teachers suggest a complex integration of these influences. One is their intuitive thinking, which deserves a closer investigation in future research. The other proposes that each teacher's decisions are ...
Date: May 2013
Creator: Parris, Sheri Rene’
Partner: UNT Libraries

Accountability in Schools: a Study of High School Accountability Ratings and College Success

Description: The purpose of this study was to determine the relationship between high school campus accountability ratings, college readiness indicators, and the percent of students who achieved first year college success. Correlation and multiple regression analyses were used to analyze the relationship between the variables. Data was analyzed for two-year and four-year postsecondary educational institutions which were divided by eight school district types. Regression analysis of the relationship between high school campus accountability ratings and the percent of students who achieved first year college success for four- year post secondary educational institutions revealed statistically significant results ranging from R2 =.179 to R2 = .220. Similar results were found for two-year post secondary educational institutions with statistically significant results ranging from R2 = .049 to R2 = .218. The results indicated negligible to small relationships between the variables. Regression results of the analysis for the relationship between college readiness indicators and the percent of students who achieved first year college success revealed statistically significant results for 2 - year post secondary educational institutions ranging from R2 = .077 to R2 = .596 and for 4 -year post secondary educational institutions ranging from R2 = .048 to R2 = .304. These results indicated small to moderate relationships between college readiness indicators and the percent of students who achieve first year college success.
Date: August 2013
Creator: Orsborn, Shannon
Partner: UNT Libraries