UNT Theses and Dissertations - 3,321 Matching Results

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The Relationship between Teacher Attrition and Student Achievement in Reading among Middle School Students

Description: The purpose of this study was to determine whether a significant relationship existed between teacher attrition and student success in middle school reading by conducting a quantitative analysis. Additionally, the inclusion of school demographic characteristics were included in the model to consider previous findings referencing the challenges schools face in attracting and retaining teachers in low performing urban schools with high populations of economically disadvantaged and minority students. In this analysis, the relationship between teacher attrition and student achievement in middle school as measured by the State of Texas Assessments of Academic Readiness (STAAR) for reading among middle school students in Grades 6, 7, and 8, as reported on the Texas Academic Performance Reports (TAPR), were examined. The regression models used to analyze the three research questions addressed in the study include an examination of teacher attrition on campus pass rates, and grade level pass rates for sixth, seventh, and eighth grades as measured by the STAAR Reading assessment. The data utilized in this study were collected from seven North Texas middle schools in a fast growth school district together with their comparable campuses as identified by the Texas Education Agency for the school years 2013-2014 through 2015-2016. The results of the analysis indicate teacher attrition accounts for a significant variance in STAAR Reading pass rates among middle school students. Additionally, the school demographic characteristics defined as percentage economically disadvantaged, percentage English language learners, mobility rates, and percentage white students account for 83.4% of the variance in the average campus pass rates for STAAR Reading when combined.
Date: August 2017
Creator: Perkins, Gwendolyn Moseley
Partner: UNT Libraries

Teaching Behavior Professionals to Use the Interview-Informed Synthesized Contingency Analysis (IISCA): A Preliminary Investigation

Description: We assessed the implementation accuracy and fidelity of two board certified behavior analysts (BCBAs) using the open-ended interview from Hanley. Participants interviewed a confederate using the open-ended interview, and were then asked to use information gathered from the interview to create operational definitions of target behaviors as well as test and control condition procedures for a subsequent matched test-control functional analysis as is characteristic of the interview-informed synthesized contingency analysis (IISCA) strategy. Brief behavioral skills training (BST) was then implemented with all participants to increase the accuracy of constructing both target behavior definitions and functional analysis procedures. Preliminary results show moderate rates of accuracy of target behavior definitions and functional analysis procedures prior to BST, and high rates of accuracy following BST. The results also suggest high implementation fidelity on the open-ended interview may not be necessary to achieve high accuracy when constructing target behavior definitions and functional analysis procedures.
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Date: August 2017
Creator: Metras, Rachel
Partner: UNT Libraries

Kinetic Study of the Reactions of Chlorine Atoms with Fluoromethane and Fluoromethane-d3 in the Gas Phase

Description: The kinetics of the gas-phase reactions of chlorine atoms with fluoromethane (CH3F) and fluoromethane-d3(CD3F) were tested experimentally. The relative rate method was applied by using CH4 as the reference compound for fluoromethane (CH3F) and CH4 and CH3F as the reference compound for fluoromethane-d3(CD3F). The rate constants for H-abstraction from CH3F and D-abstraction from CD3F were measured at room temperature and a total pressure of 920 Torr using Ar as a diluent. The rate constants are described by the expressions: kH= (3.50±0.52) x 10-13 cm3 molecule-1 s-1 and kD=(5.0±0.51) x 10-14 cm3 molecule-1 s-1. The kinetic isotope effect, equal to the ratio kH/kD, was found to be 7.0±1.2 at room temperature.
Date: August 2017
Creator: Shao, Kejun
Partner: UNT Libraries

"Second Life, Second Chance"

Description: This is a collection of two stories, one fiction and one non-fiction, in communication with one another. Both stories explore how trauma can transform a life. In "Tabula Rasa," Mena is unable to recall her past after being beaten and left for dead. She must choose whether to uncover her past or forget it and move forward with her life. Set in a town run by witches, Mena learns that both choices are dangerous. In "Eternal Second," the narrator recounts the aftermath of her husband's suicide. She explores how trauma invades all aspects of her life. In both stories, women must navigate a new life created by the destruction of the old one.
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Date: August 2017
Creator: Beattie, Jessica Kathrine
Partner: UNT Libraries

Development and Analysis of a Mobile Node Tracking Antenna Control System

Description: A wireless communication system allows two parties to exchange information over long distances. The antenna is the component of a wireless communication system that allows information to be converted into electromagnetic radiation that propagates through the air. A system using an antenna with a highly directional beam pattern allows for high power transmission and reception of data. For a directional antenna to serve its purpose, it must be accurately pointed at the object it is communicating with. To communicate with a mobile node, knowledge of the mobile node's position must be gained so the directional antenna can be regularly pointed toward the moving target. The Global Positioning System (GPS) provides an accurate source of three-dimensional position information for the mobile node. This thesis develops an antenna control station that uses GPS information to track a mobile node and point a directional antenna toward the mobile node. Analysis of the subsystems used and integrated system test results are provided to assess the viability of the antenna control station.
Date: August 2017
Creator: Hensley, Phillip Hayden
Partner: UNT Libraries

The Impact of Commuting on Mental Health

Description: The purpose of this research is to explicate the relationship between commuting behavior, stress, and mental health. The overall results from the regression analysis turned out to be inconclusive given the researcher's initial hypothesis. The commute time reported by respondents did not have a statistically significant bearing on mental health outcomes. This was true for both the normal sample, and the sample that was split by gender.
Date: August 2017
Creator: Malek-Ahmadi, John H.
Partner: UNT Libraries

A General Approach to Buhlmann Credibility Theory

Description: Credibility theory is widely used in insurance. It is included in the examination of the Society of Actuaries and in the construction and evaluation of actuarial models. In particular, the Buhlmann credibility model has played a fundamental role in both actuarial theory and practice. It provides a mathematical rigorous procedure for deciding how much credibility should be given to the actual experience rating of an individual risk relative to the manual rating common to a particular class of risks. However, for any selected risk, the Buhlmann model assumes that the outcome random variables in both experience periods and future periods are independent and identically distributed. In addition, the Buhlmann method uses sample mean-based estimators to insure the selected risk, which may be a poor estimator of future costs if only a few observations of past events (costs) are available. We present an extension of the Buhlmann model and propose a general method based on a linear combination of both robust and efficient estimators in a dependence framework. The performance of the proposed procedure is demonstrated by Monte Carlo simulations.
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Date: August 2017
Creator: Yan, Yujie yy
Partner: UNT Libraries

MBE Growth and Characterization of Graphene on Well-Defined Cobalt Oxide Surfaces: Graphene Spintronics without Spin Injection

Description: The direct growth of graphene by scalable methods on magnetic insulators is important for industrial development of graphene-based spintronic devices, and a route towards substrate-induced spin polarization in graphene without spin injection. X-ray photoelectron spectroscopy (XPS), low energy electron diffraction LEED, electron energy loss spectroscopy (EELS) and Auger electron spectroscopy (AES) demonstrate the growth of Co3O4(111) and CoO(111) to thicknesses greater than 100 Å on Ru(0001) surfaces, by molecular beam epitaxy (MBE). The results obtained show that the formation of the different cobalt oxide phases is O2 partial pressure dependent under same temperature and vacuum conditions and that the films are stoichiometric. Electrical I-V measurement of the Co3O4(111) show characteristic hysteresis indicative of resistive switching and thus suitable for advanced device applications. In addition, the growth of Co0.5Fe0.5O(111) was also achieved by MBE and these films were observed to be OH-stabilized. C MBE yielded azimuthally oriented few layer graphene on the OH-terminated CoO(111), Co0.5Fe0.5O(111) and Co3O4(111). AES confirms the growth of (111)-ordered sp2 C layers. EELS data demonstrate significant graphene-to-oxide charge transfer with Raman spectroscopy showing the formation of a graphene-oxide buffer layer, in excellent agreement with previous theoretical predictions. XPS data show the formation of C-O covalent bonding between the oxide layer and the first monolayer (ML) of C. LEED data reveal that the graphene overlayers on all substrates exhibit C3V. The reduction of graphene symmetry to C3V – correlated with C-O bond formation – enables spin-orbit coupling in graphene. Consequences may include a significant band gap and room temperature spin Hall effect – important for spintronic device applications. The results suggest a general pattern of graphene/graphene oxide growth and symmetry lowering for graphene formation on the (111) surfaces of rocksalt-structured oxides.
Date: August 2017
Creator: Olanipekun, Opeyemi B
Partner: UNT Libraries

Assessment of Competencies among Doctoral Trainees in Psychology

Description: The recent shift to a culture of competence has permeated several areas of professional psychology, including competency identification, competency-based education training, and competency assessment. A competency framework has also been applied to various programs and specialty areas within psychology, such as clinical, counseling, clinical health, school, cultural diversity, neuro-, gero-, child, and pediatric psychology. Despite the spread of competency focus throughout psychology, few standardized measures of competency assessment have been developed. To the authors' knowledge, only four published studies on measures of competency assessment in psychology currently exist. While these measures demonstrate significant steps in progressing the assessment of confidence, three of these measures were designed for use with individual programs, two of these international (i.e., UK and Taiwan). The current study applied the seminal Competency Benchmarks, via a recently adapted benchmarks form (i.e., Practicum Evaluation form; PEF), to practicum students at the University of North Texas. In addition to traditional supervisor ratings, the present study also involved self-, peer supervisor, and peer supervisee ratings to provide 360-degree evaluations. Item-response theory (IRT) was used to evaluate the psychometric properties of the PEF and inform potential revisions of this form. Supervisor ratings of competency were found to fit the Rasch model specified, lending support to use of the benchmarks framework as assessed by this form. Self- and peer-ratings were significantly correlated with supervisor ratings, indicating that there may be some utility to 360-degree evaluations. Finally, as predicted, foundational competencies were rated as significantly higher than functional competencies, and competencies improved significantly with training. Results of the current study provide clarity about the utility of the PEF and inform our understanding of practicum-level competencies.
Date: August 2017
Creator: Price, Samantha
Partner: UNT Libraries

Development of a Natural Fiber Mat Plywood Composite

Description: Natural fibers like kenaf, hemp, flax and sisal fiber are becoming alternatives to conventional petroleum fibers for many applications. One such applications is the use of Non-woven bio-fiber mats in the automobile and construction industries. Non-woven hemp fiber mats were used to manufacture plywood in order to optimize the plywood structure. Hemp fiber mats possess strong mechanical properties that comparable to synthetic fibers which include tensile strength and tensile modulus. This study focuses on the use of hemp fiber mat as a core layer in plywood sandwich composite. The optimization of fiber mat plywood was done by performing a three factor experiment. The three factors selected for this experiment were number of hemp mat layers in the core, mat treatment of the hemp mat, and the glue content in the core. From the analysis of all treatments it was determined that single hemp mat had the highest effect on improving the properties of the plywood structure.
Date: August 2017
Creator: Anthireddy, Prasanna Kumar
Partner: UNT Libraries

Community of Inquiry Meets Critical Discourse Analysis (CDA): A CDA of Asynchronous Computer-Conference Discourse with Seminary Students in India

Description: The purpose of this study was to better understand student learning in asynchronous computer-conference discourse (ASD) for non-native speakers of English in India through the Community of Inquiry (COI) framework. The study looked at ASD from an online course taught in the fall of 2015 to 25 students in a seminary in South India. All but one of the students were non-native speakers of English. The class consisted of 22 men and 3 women. Eight students spoke languages from the Dravidian family of languages (Malayalam, Tamil, Telegu and Kannada). Eight students were from the Northeastern states of Manipur, Nagaland and Tripura, where most languages are from the Sino-Tibetan family. Three students were native speakers of Indo-Aryan languages (Odiya and Assamese). Five students were from Myanmar representing several Sino-Tibetan languages. The COI is a framework used to understand learning in ASD, often used in online learning. To study the ASD of this group, critical discourse analysis (CDA) was used with the COI to capture the unique socio-cultural and linguistic conditions of this group. The study revealed that non-native speakers of English often reach the Exploration phase of learning but rarely show evidence of reaching the Resolution phase. This phenomenon was also observed in native English speakers as reported in the literature. Also, the structure of ASD showed that students took an examination approach to discussion shaped in part by their epistemology. This examination approach shaped how knowledge was constructed. CDA also showed that the discourse acquired an instructor-centered structure in which Resolution and Repair were initiated and finalized by the instructor. The study advances the COI framework by undergirding it with a theory of asynchronous discourse using critical discourse analysis and capturing cognitive, social and teaching presence phenomena for non-native speakers that were not observed through the traditional COI framework. These ...
Date: August 2017
Creator: George, Stephen J
Partner: UNT Libraries

A Case Study of Mathematics Teachers' Use of Short-Cycle Formative Assessment Strategies

Description: A single case study was used to examine two middle grades mathematics teachers' use of short-cycle formative assessment strategies. Data was collected using multiple sources to provide a description of this single case. Participant change in knowledge of short-cycle formative assessment strategies was collected and analyzed through participant pre- and post-interviews and targeted instructional support was provided through professional development sessions designed to meet diverse needs of participants. Participant change in use of short-cycle formative assessment strategies was collected and analyzed through classroom observations using Assess Today observation protocol and targeted instructional support was provided through post-observation conferences with written feedback. Findings from the study verified that changes in teachers' use of short-cycle formative assessment strategies were positively influenced by the targeted instructional support provided to each participant during the study. The study further indicated that an assessment of teacher's present knowledge and use of short-cycle formative assessment strategies should be considered before providing targeted instructional support to maximize the learning potential for each teacher. Future research is needed regarding the importance of building student self-efficacy through teacher use of short-cycle formative assessment, as well as the importance of involving students in the formative assessment process.
Date: August 2017
Creator: Davis, Adreana A
Partner: UNT Libraries

Microwave-Assisted Synthesis and Photophysical Properties of Poly-Imine Ambipolar Ligands and Their Rhenium(I) Carbonyl Complexes

Description: The phenomenon luminescence rigidochromism has been reported since the 1970s in tricarbonyldiimine complexes with a general formula [R(CO)3LX] using conventional unipolar diimine ligands such as 2,2;-bipyridine or 1,10-phenanthroline as L, and halogens or simple solvents as X. As a major part of this dissertation, microwave-assisted synthesis, purification, characterization and detailed photoluminescence studies of the complex fac-[ReCl(CO)3L], 1, where L = 4-[4,6-bis(3,5-dimethyl-1H-pyrazol-1-yl]-N,N-diethylbenzenamine are reported. The employment of microwaves in the preparation of 1 decreased the reaction time from 48 to 2 hours compared to the conventional reflux method. Stoichiometry variations allows for selective preparation of either a mononuclear, 1, or binuclear, fac-[Re2Cl2(CO)6], 2, complex. The photophysical properties of 1 were analyzed finding that it possesses significant luminescence rigidochromism. The steady state photoluminescence emission spectra of 1 in solution shift from 550 nm in frozen media to 610 nm when the matrix becomes fluid. Moreover, a very sensitive emission spectral analysis of 0.1 K temperatures steps shows a smooth transition through the glass transition temperature of the solvent host. Furthermore, synthetic modifications to L have attained a family of ambipolar compounds that have tunable photophysical, thermophysical and other material properties that render them promising candidates for potential applications in organic electronics and/or sensors - either as is or for their future complexes with various transition metals and lanthanides.
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Date: August 2017
Creator: Salazar Garza, Gustavo Adolfo
Partner: UNT Libraries

The King Arrives: Chinese Government Inspections and Their Effects

Description: This dissertation studies a critical facet of Chinese politics, inspections by higher Chinese government to villages. Principally, it looks at how village economic development determines government inspection decisions and how inspections, once conducted, impact village politics. Specifically, I argue that villages perceived as destabilizing to the Chinese regime, villages with higher levels of economic inequality and villages located at the two extremes of economic development, should see more inspections. In addition, I argue that inspections, in return, drive village politics: they increase village leaders' governing efficacy and raise villagers' political awareness. This theory has received strong support from both field work and quantitative empirical tests using the Chinese Household Income Project (2002) dataset.
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Date: August 2017
Creator: Xi, Jinrui
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Mobile-Based Smart Auscultation

Description: In developing countries, acute respiratory infections (ARIs) are responsible for two million deaths per year. Most victims are children who are less than 5 years old. Pneumonia kills 5000 children per day. The statistics for cardiovascular diseases (CVDs) are even more alarming. According to a 2009 report from the World Health Organization (WHO), CVDs kill 17 million people per year. In many resource-poor parts of the world such as India and China, many people are unable to access cardiologists, pulmonologists, and other specialists. Hence, low skilled health professionals are responsible for screening people for ARIs and CVDs in these areas. For example, in the rural areas of the Philippines, there is only one doctor for every 10,000 people. By contrast, the United States has one doctor for every 500 Americans. Due to advances in technology, it is now possible to use a smartphone for audio recording, signal processing, and machine learning. In my thesis, I have developed an Android application named Smart Auscultation. Auscultation is a process in which physicians listen to heart and lung sounds to diagnose disorders. Cardiologists spend years mastering this skill. The Smart Auscultation application is capable of recording and classifying heart sounds, and can be used by public or clinical health workers. This application can detect abnormal heart sounds with up to 92-98% accuracy. In addition, the application can record, but not yet classify, lung sounds. This application will be able to help save thousands of lives by allowing anyone to identify abnormal heart and lung sounds.
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Date: August 2017
Creator: Chitnis, Anurag Ashok
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A Woman's Place is at Work: The Rise of Women's Paid Labor in Five Texas Cities, 1900-1940

Description: This thesis is a quantitative analysis of women working for pay aged sixteen and older in five mid-size Texas cities from 1900 to 1940. It examines wage-earning women primarily in terms of race, age, marital status, and occupation at each census year and how those key factors changed over time. This study investigates what, if any, trends occurred in the types of occupations open to women and the roles of race, age, and marital status in women working for pay in the first forty years of the 20th century.
Date: August 2017
Creator: Scott, Codee
Partner: UNT Libraries

A Systemic Model for Family Functioning: Mutual Influences of Spousal Attachment, Marital Adjustment, and Coparenting

Description: The current study examined direct and indirect influences of romantic attachment processes, marital adjustment, and the coparenting relationship on family functioning. Data was collected from a community sample of 86 heterosexual couples with a child aged eight to eleven living in the home. Both spouses completed a demographic questionnaire, the Experiences in Close Relationships Scale, the Dyadic Adjustment Scale, the Coparenting Scale, and the Self-Report Family Inventory as part of a larger study on family processes in middle childhood. Data analysis included multilevel modeling, utilizing the actor-partner interdependence model. Results indicated that marital adjustment mediated the association between attachment processes and family functioning, suggesting that a healthy marital relationship is an important variable that helps explain links between attachment security and the family functioning. Findings also highlighted the benefit of conceptualizing adult romantic attachment, marital, and coparental subsystems within a systemic framework.
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Date: August 2017
Creator: Young, Anne Michelle
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"Momentarium"

Description: "Momentarium" is a collection of poems that examines the instability of moments. By engaging with photography, the poems examine the strengths and flaws in representation. Qualified accuracy, in other words representations that exact no absolute authenticity, are paradoxically, most accurate. The original poems attempt to express both empathy an end to empathy, "I mean to give you what you cannot keep: a blue twice as true" and "I mean to give you what I cannot." The competing forces animate a contingent moment, before it becomes the past.
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Date: August 2017
Creator: Zuehlke, Karl
Partner: UNT Libraries

Best Practices in Targeted Advertising for Fashion Entrepreneurs

Description: A key to a business's success is reaching the target market. This ensures that consumers are exposed to the retailer's offerings and by turn, inspired to purchase. In turn, the business can reach its goal of a profitable organization. The purpose of this paper was to determine the most effective fashion advertising appeals for reaching target markets. To address these issues, this thesis consisted of two studies. The purpose of the first study was to determine the advice given to fashion entrepreneurs regarding effective target market practices. The purpose of the second study was to determine effective advertising strategies fashion entrepreneurs may employ for effectively reaching target markets. Data was collected to test the effectiveness of the advice from Study 1, degrees of brand awareness, attitudes towards advertising, willingness to follow trends, purchase intention, purchase behavior, and shopping involvement. The Theory of Reasoned Action was employed as the theoretical framework of the study. The framework was utilized to predict that attitudes towards targeted advertising and pressure to follow fashion trends would positively relate to intent to purchase which, in turn, would positively relate to purchase behavior. The results of this paper concluded the TRA model provided a proper framework to predict purchase behavior from targeted advertising employed by fashion entrepreneurs.
Date: August 2017
Creator: Slaton, Kelcie Shaelyn
Partner: UNT Libraries

Investigation of Immersion Cooled ARM-Based Computer Clusters for Low-Cost, High-Performance Computing

Description: This study aimed to investigate performance of ARM-based computer clusters using two-phase immersion cooling approach, and demonstrate its potential benefits over the air-based natural and forced convection approaches. ARM-based clusters were created using Raspberry Pi model 2 and 3, a commodity-level, single-board computer. Immersion cooling mode utilized two types of dielectric liquids, HFE-7000 and HFE-7100. Experiments involved running benchmarking tests Sysbench high performance linpack (HPL), and the combination of both in order to quantify the key parameters of device junction temperature, frequency, execution time, computing performance, and energy consumption. Results indicated that the device core temperature has direct effects on the computing performance and energy consumption. In the reference, natural convection cooling mode, as the temperature raised, the cluster started to decease its operating frequency to save the internal cores from damage. This resulted in decline of computing performance and increase of execution time, further leading to increase of energy consumption. In more extreme cases, performance of the cluster dropped by 4X, while the energy consumption increased by 220%. This study therefore demonstrated that two-phase immersion cooling method with its near-isothermal, high heat transfer capability would enable fast, energy efficient, and reliable operation, particularly benefiting high performance computing applications where conventional air-based cooling methods would fail.
Date: August 2017
Creator: Mohammed, Awaizulla Shareef
Partner: UNT Libraries

Are Streams Protected? Outcomes of Environmental Regulation

Description: Urban areas experience the loss of natural stream channels through conversion to artificial conveyances. This process tends to target headwater and other low order streams. The purpose of this study is to determine the patterns of stream loss in Denton, Texas, and explore the regulatory structure that manages these streams. Historic and current maps and stream data are used to map Denton's streams and categorize them according to their vertical connectivity as: 1) "intact", streams that are open to the atmosphere and connect to groundwater; 2) "concrete", channelized streams open to the atmosphere but cut off from groundwater; and 3) "buried", streams disconnected from the atmosphere and groundwater. A review of federal, state, and local regulatory codes and interviews with local government officials and other stakeholders elucidates stream management in Denton. Results from these analyses reveal high rates of stream loss in the urban center with low rates overall. The federal Clean Water Act and the local Environmentally Sensitive Areas code serve as the primary protective measures for natural streams. These regulations discourage stream impacts through expensive and complex permitting requirements. However the policies allow minor impacts which may cause cumulative effects. This study aims to inform future policy-making decisions and contribute to the knowledge of the environmental regulation of streams.
Date: August 2017
Creator: Rowen, Zachary
Partner: UNT Libraries

Predictors of Postsecondary Success: An Analysis of First Year College Remediation

Description: This study was a quantitative multiple regression investigation into the relationships between campus factors of high school students graduating in 2013 who immediately enrolled in first-year college freshman level remedial coursework at a large, Central Texas two-year postsecondary institution. The goal of this study was to determine which high school campus-level factors predicted enrollment into college remedial education coursework. The dependent variable was a continuous variable representing the percentage of students from Texas public high school campuses enrolled into at least one student credit hour of remedial education during their first semester as a first-year college student. Eight high school campus-level independent variables were included in the regression model at the campus-level: at risk percentage, economically disadvantaged percentage, limited English proficient percentage, advanced course/dual-enrollment percentage, college ready math percentage, college ready English percentage, ACT average, and SAT average. Pearson correlations and linear regression results were examined and interpreted to determine the level of relationship between the eight selected variables and first-year college student remedial coursework. The multiple regression model successfully explained 26.3% (F(8,286) = 12.74. p < 0.05, r2 = 0.263) of the variance between first-year college students enrolled into remedial coursework at a large, Central Texas two-year postsecondary institution and the campus-level variables from high schools from which they graduated and indicated campus-level economic disadvantaged percentage and campus-level SAT average to be statistically significant at the p < 0.05 level.
Date: August 2017
Creator: Baker, Emmett Andrew
Partner: UNT Libraries

Effect of Surface Treatment on the Performance of CARALL, Carbon Fiber Reinforced Aluminum Joints

Description: Fiber-metal laminates (FML) are the advanced materials that are developed to improve the high performance of lightweight structures that are rapidly becoming a superior substitute for metal structures. The reasons behind their emerging usage are the mechanical properties without a compromise in weight other than the traditional metals. The bond remains a concern. This thesis reviews the effect of pre-treatments, say heat, P2 etch and laser treatments on the substrate which modifies the surface composition/roughness to impact the bond strength. The constituents that make up the FMLs in our present study are the Aluminum 2024 alloy as the substrate and the carbon fiber prepregs are the fibers. These composite samples are manufactured in a compression molding process after each pre-treatment and are then subjected to different tests to investigate its properties in tension, compression, flexural and lap shear strength. The results indicate that heat treatment adversely affects properties of the metal and the joint while laser treatments provide the best bond and joint strength.
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Date: August 2017
Creator: Bandi, Raghava
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A Mixed Methods Approach to Exploring Social Support and Resilience in Coping with Stigma and Psychological Distress among HIV-Positive Adults

Description: Since its emergence in the U.S., HIV has been a stigmatized illness. People living with HIV (PLH) are a minority and prone to psychological distress and poor mental health outcomes due to HIV-related stigma. PLH who identify with another minority group in addition to being HIV-positive (e.g., gay, African-American) experience multiple forms of oppression or layered stigma. Affirmative social support and resilience are negatively associated with HIV-stigma and are important coping resources for PLH. We used an explanatory sequential mixed methods design study involving a quantitative survey phase and a qualitative interview phase. We explored whether social support and resilience (Positive Psychological Resources) mediate or moderate the relationship between HIV Stigma and Psychological Distress among HIV-positive adults using partial least squares (PLS) path modeling and multiple regressions. Via PLS, we found Positive Psychological Resources partially mediated the relationship between HIV Stigma and Psychological Distress: the path between HIV Stigma and Psychological distress reduced (from t = 5.49, p = .000 to t = 2.39, p = .000) but remained statistically significant. Similarly, via regression, the Sobel test was significant (Sobel = .26, SE = .07, z = 3.63, p = .000). However, moderation was not found (HIV Stigma x Positive Psychological Resources β = .05, t = .66, p = .508). Overall, our quantitative survey and qualitative interview data were consistent. We anticipate that our findings will inform strengths-based therapeutic interventions to mitigate stress and stigma among PLH.
Date: August 2017
Creator: Fritz, Sarah-mee
Partner: UNT Libraries