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Exploring the ROI of 1:1 Computing Programs at the High School Level (open access)

Exploring the ROI of 1:1 Computing Programs at the High School Level

This dissertation explored the cost and value of 1:1 computing programs in high schools in Texas. The study examines whether the total cost of ownership of these programs can be justified by the student testing gains and graduation rates. It investigates whether student learning outcomes show a definable correlation between positive gains and the implementation of 1:1 computing programs. The study also explores whether there is a measurable return on investment of 1:1 programs based on testing gains and graduation rates. The research used the State of Texas Assessment of Academic Readiness exam scores to validate assumptions and test the hypothesis. The study found no clear link between the addition of 1:1 computing programs and the realms of student success. While there is marginal improvement in student outcomes, there is only circumstantial evidence that laptops and devices are the catalysts for the change. The dissertation also found that the total cost of ownership (TCO) is a significant portion of the district's spending, costing millions of dollars, and that the financial disclosure and budget information data was either missing, incomplete, or over-generalized, causing an issue for assessing program effectiveness or ROI. Despite this lack of transparency, there is a slight positive …
Date: December 2023
Creator: Kissel, Tara Michelle
System: The UNT Digital Library
Utility Trombone Playing: A Practical Method for Students to Achieve Mastery of Alto, Tenor and Bass Trombone (open access)

Utility Trombone Playing: A Practical Method for Students to Achieve Mastery of Alto, Tenor and Bass Trombone

With the importance of versatility in freelance work in the world of trombone performance, along with increased competition for that work, the need for players to play alto, tenor, and bass trombones to a high level of proficiency has become more and more crucial. This, coupled with the growing number of orchestras looking to hire musicians who are highly competent on all three instruments means that university professors need to be able to teach all three instruments. This evolution of the job market is driving a need for pedagogical material that is specifically designed to address the unique challenges of practicing and performing at a professional level on the main three instruments in the trombone family. As of the time of writing, this material simply does not exist. This project aims to fill that instructional gap. It gives students and teachers a resource that outlines an approach for a four-year undergraduate course of study that allows for the development of the playing of each of the trombones individually and collectively, utilizing the strengths of one instrument to develop the other two. It will also allow for the exploration of the technical challenges that arise when playing and changing between instruments. …
Date: December 2023
Creator: Owner, Timothy Michael
System: The UNT Digital Library

Remotely Controlled Magneto-Phononic Devices Achieving Nonreciprocity and Anderson Localization in Ferrofluid

Motivated by previous relevant research on phononics including both active and passive phononics, the interest of faster turnability and more functions of the active phononics of further study led to this proposing research topic: magnetic field tunable active functional phononics. The first design of magnetic field tunable reciprocal--non-reciprocal transmission acoustic device was established, material was characterized, and numerical simulation has been performed. The simulation results show clear T-symmetric breaking non-reciprocity due to energy level splitting effect with Doppler effect – an acoustic Zeeman effect. Inspired by this preliminary work, further experiments were planned to demonstrate this effective Zeeman effect in phononics and effectively charged phonons in water based ferro-fluid. The objectives of this work as the next series of tasks were to illustrate acoustic Zeeman effect and acoustic Landau levels in various strength of magnetic field to investigate a design non-reciprocal sound device with magnetic field switching, which could be controlled on the amount of non-reciprocity with the strength of magnetic field. Once this new field first discovered by the proposed study tasks, more active tunable magnetic field phononics devices could be designed and exemplified in terms of both simulations and experiments. Faster and more controllable active phononic devices could …
Date: December 2021
Creator: Jin, Yuqi
System: The UNT Digital Library
A Mixed Methods Approach to Exploring Social Support and Resilience in Coping with Stigma and Psychological Distress among HIV-Positive Adults (open access)

A Mixed Methods Approach to Exploring Social Support and Resilience in Coping with Stigma and Psychological Distress among HIV-Positive Adults

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 …
Date: August 2017
Creator: Fritz, Sarah-mee Hesse
System: The UNT Digital Library
Neurocognitive Effects of Gist Reasoning Training in Student-Athletes with Concussions, ADHD, and Learning Disabilities (open access)

Neurocognitive Effects of Gist Reasoning Training in Student-Athletes with Concussions, ADHD, and Learning Disabilities

Concussions, attention-deficit disorder (ADHD), and learning disabilities can adversely impact learning and academic achievement, particularly with respect to attention, memory, and executive functioning; fortunately, cognitive training can be beneficial and remediating these weaknesses. One such program, strategic memory advanced reasoning training (SMART), utilizes a top-down approach to train individuals in executive, higher-ordered thinking strategies including strategic attention, integration, and innovation to facilitate information synthesis and enhance cognitive efficiency. Thus, the purpose of the study is to examine whether SMART improved performances on various neuropsychological measures tapping into attention, processing speed, memory, and executive functioning for college student-athletes with neurological conditions (e.g., concussions, ADHD, LD). Student-athletes were randomly assigned to the SMART program or a "wait-list" control group and were administered a neuropsychological battery at baseline, immediately following the intervention, and after a four-month delay. Results showed that participants benefited from SMART with respect to working memory immediately following the intervention after controlling for baseline scores. The benefits of working memory also persisted after four months. Additionally, SMART was beneficial for improving attention, but only after four months after the intervention. The findings of the current study were consistent with previous studies which showed positive effects of SMART on working memory …
Date: August 2017
Creator: Nguyen, Thomas (Clinical neuropsychologist)
System: The UNT Digital Library

Corrosion Mechanism and Prevention of Wire Bonded Device in Microelectronic Manufacturing and Spectroscopic Investigation of Copper Etch Chemical Equilibria for High Density Interconnect Application

In the first part of this dissertation work, Al bond pad corrosion behavior was investigated in the presence of common industrial contaminants such as chloride (Cl-) and fluoride (F-). Al corrosion while in direct contact with Cu displayed rapid hydrogen (H2) gas evolution and dendrite propagation. In contrast, Al without bimetallic contact showed only minor surface roughening. This observed difference in the corrosion mechanism between Cl- and F- is attributed to the solubility of the corrosion products (AlCl3 vs. AlF3) formed on the Al surface. Our subsequent work explored corrosion prevention inhibition of wire-bonded devices (WBD) in the Cl- environment. Our research shows that the Al bond pad was protected against corrosion by chemically modifying the surface of the Cu wires, thereby preventing the H2 evolution. The inhibitor was observed to be highly selective, thermally stable, hydrophobic, and cost-effective, making it viable for industrial application of this coating for Al bond pad corrosion prevention. In the second part of the dissertation work, we utilized a novel approach of using ultraviolet-visible spectroscopy (UV-Vis) as a chemical-sensitive monitoring tool of the chemical environment in Cu etch bath. The UV-Vis technique illuminates the roles of H+, Cl-, Cu+, and Cu2+ to the etch …
Date: December 2021
Creator: Ashok Kumar, Goutham Issac
System: The UNT Digital Library
Instrumental Development and Implementation of Portable Membrane Inlet Mass Spectrometry for Homeland Security and Environmental Applications (open access)

Instrumental Development and Implementation of Portable Membrane Inlet Mass Spectrometry for Homeland Security and Environmental Applications

A rapidly growing topic of great interest is the adaptation of benchtop analytical instrumentation for use in outdoor harsh environments. Some of the areas that stand to benefit from field instrumentation development include government agencies involved with the preservation of the environment and institutions responsible for the safety of the general public. Detection systems are at the forefront of the miniaturization movement as the interest in analyte identification and quantitation appears to only be accessible through the use of analytical instrumentation. Mass spectrometry is a distinguished analytical technique known for its ability to detect the mass-to-charge (m/z) ratios of gas-phase ions of interest. Although these systems have been routinely limited to research lab-based analysis, there has been considerable development of miniaturized and portable mass spectrometry systems. Membrane Inlet Mass Spectrometry (MIMS) is becoming a common method of sample introduction that is subject to significant development. MIMS allows for minimal sample preparation, continuous sampling, and excludes complicated analyte introduction techniques. Sampling is accomplished using a semipermeable membrane that allows selective analyte passage into the vacuum of the mass spectrometer. MIMS is becoming the preeminent choice of homeland security and environmental monitoring applications with increasing opportunities for the future development of specialized …
Date: December 2021
Creator: Anguiano Virgen, Camila
System: The UNT Digital Library

Forging Pathways: A Multi-Case Study of Individuals with Intellectual Disability Pursuing Postsecondary Education at the Community College

This multi-case study sought to better understand how students with intellectual disability (ID) are forging pathways to higher education via the community college. Five individuals with ID who accessed higher education via the community college and their parents/guardians were interviewed. Each case provided insight into personal pathways with results given in case descriptions and individual case themes. Cross-case analysis revealed four themes positively impacting the college-going pathway for students with ID: value-driven grit, pathway knowledge, community support, and accessibility. Based on findings from this study, families appear to be the primary systems forging pathways to the community college for individuals with ID. Local education agencies and community colleges can assist these families by engaging in interagency collaboration, evaluating their systems, and aligning practices to the goal of students with ID accessing and engaging in higher education.
Date: December 2021
Creator: Jackson, Amanda O.
System: The UNT Digital Library

Advanced Cathodes for High Energy Density Lithium Sulfur Battery

A systematic development of 2D alloy catalyst with synergistic performance of high lithium polysulfide (LiPS) binding energy and efficient Li+ ion/electron conduction is presented. The first section of work found that Li+ ions can flow through the percolated ion transport pathway in polycrystalline MoS2, while Na+ and K+ ions can easily flow through the percolated 1D ion channel near the grain boundaries. An unusually high ionic conductivity of extrinsic Li+, Na+, and K+ ions in 2D MoS2 film exceeding 1 S/cm was measured that is more than two orders of magnitude higher than those of conventional solid ionic materials, including 2D ionic materials. The second section of this dissertation focus on catalyzing the transformation of LiPSs to prevent the shuttle effect during the battery cycling by synthesizing 2H (semiconducting) – 1T (metallic) mixed phase 2D Mo0.5W0.5S2 alloy on CNF paper, using two step sputtering and sulfurization method. The lithium sulfur (Li-S) battery cell assembled with the 2D Mo0.5W0.5S2/CNF/S cathode shows a high specific capacity of 1228 mAh g-1 at 0.1C and much higher cyclic stability over 4 times as compared to the pristine cathodes. The high LiPSs binding energy of catalyst efficiently prevents the shuttling effect and corrosion of Li …
Date: December 2021
Creator: Bhoyate, Sanket
System: The UNT Digital Library

Reliability Characterization and Performance Analysis of Solid State Drives in Data Centers

NAND flash-based solid state drives (SSDs) have been widely adopted in data centers and high performance computing (HPC) systems due to their better performance compared with hard disk drives. However, little is known about the reliability characteristics of SSDs in production systems. Existing works that study the statistical distributions of SSD failures in the field lack insights into distinct characteristics of SSDs. In this dissertation, I explore the SSD-specific SMART (Self-Monitoring, Analysis, and Reporting Technology) attributes and conduct in-depth analysis of SSD reliability in a production environment with a focus on the unique error types and health dynamics. QLC SSD delivers better performance in a cost-effective way. I study QLC SSDs in terms of their architecture and performance. In addition, I apply thermal stress tests to QLC SSDs and quantify their performance degradation processes. Various types of big data and machine learning workloads have been executed on SSDs under varying temperatures. The SSD throughput and application performance are analyzed and characterized.
Date: December 2021
Creator: Liang, Shuwen (Computer science and engineering researcher)
System: The UNT Digital Library
Unraveling the Effect of Atomic Configurations and Structural Statistics on Mechanical Behavior of Multicomponent and Amorphous Alloys (open access)

Unraveling the Effect of Atomic Configurations and Structural Statistics on Mechanical Behavior of Multicomponent and Amorphous Alloys

Multicomponent high-entropy and amorphous alloys represent relatively new classes of structural materials with complex atomic configurations and exceptional mechanical properties. However, there are several knowledge gaps in the relationships between their atomic structure and mechanical properties. Understanding these critical relationships will enable novel alloy design and tailoring of their mechanical properties for desired engineering applications. In this dissertation, first-principles calculations and molecular dynamics simulations are applied to investigate the local atomic configurations and ordering in high-entropy and amorphous alloys. Our findings suggest that fluctuations in local atomic configurations for high- entropy alloys result in significant changes in stacking fault energy, twin energy, dislocation behavior, dislocation-twin interactions, and critical shear stress. For amorphous alloys or metallic glasses, the short-range order (SRO) and medium-range order (MRO) were found to play decisive roles in determination of their mechanical properties. Structural relaxation was found to lead to shear localization, which was attributed to free volume change and evolution of SRO and MRO to more brittle nature. In contrast, rejuvenated metallic glasses had relatively large and uniform free volume distribution giving rise to homogeneous flow and increased plasticity.
Date: December 2021
Creator: Yang, Yu Chia
System: The UNT Digital Library
The Examination of Black and Latino/a/x Students' and Responsive STEM Teachers' Perceptions of Teacher Cultural Consciousness and Culturally Responsive Instructional Practices (open access)

The Examination of Black and Latino/a/x Students' and Responsive STEM Teachers' Perceptions of Teacher Cultural Consciousness and Culturally Responsive Instructional Practices

School cultures, curriculum, and instruction are too often created through a monocultural lens, which excludes Black and Latino/a/x students both socially and academically, and perpetuates the false notion that these students are inherently less capable of achieving academic success when compared to their White counterparts. This is visible across all content areas, but especially in secondary science, technology, engineering, and mathematics (STEM) classes, which means that our Black and Latino/a/x students are continually denied preparation for the critical, high demand careers in the STEM field. Just as critical, with the dominance of White teachers in the classroom, out Black and Latino/a/x students often do not have access to teachers who share their lived experiences or who understand the nuances of their home cultures. However, teachers and school instructional leaders can change course by focusing their efforts to develop a rich cultural consciousness, and by focusing on the utilization of culturally responsive pedagogy (CRP) and related instructional strategies with great intentionality in the classroom. This mixed method, single site, exploratory case study was conducted to examine Black and Latino/a/x students' perceptions of their culturally responsive STEM teachers' cultural consciousness, and culturally responsive STEM teachers' perceptions of culturally responsive practices and their …
Date: December 2021
Creator: Norris, Margaret Louise
System: The UNT Digital Library

Homoleptic and Heteroleptic Platinum(II) Complexes for Organic Light Emitting Diodes and Humidity Sensors: Synthesis, Characterization, and Applications

This dissertation focuses on the design, synthesis, characterization of platinum (II) pyridylazolate complexes and develop high performance organic light emitting diodes (OLEDs) and design and execute high-sensitivity humidity sensors based on the luminescent metal-organic complexes of platinum. A majority of existing platinum compounds do not dissolve in organic solvents, making it difficult to analyze the photophysical characteristics of complexes in solution, a key part of understanding chemical photophysical properties. Furthermore, due to the poor quantum yield, it is inefficient for use in devices such as OLEDs. Chapter 2 reports the synthesis and characterization of a novel heteroleptic platinum(II) pyridylazolate complex with high solubility and quantum yield. The photochemistry of the complex is studied, including efficiency, emission profiles, and lifetimes at different temperatures. Chapter 3 reports the power efficiency (lm/W), current efficiency (cd/A), external quantum efficiency (EQE), luminance and operating voltage (V) of OLED devices made with the heteroleptic platinum(II) pyridylazolate complex. The relation between thickness of hole transport layer and electron transport layer on performance of devices has been studied through building a variety of devices. Chapter 4 includes application of a homoleptic platinum(II) pyridylazolate complex in humidity sensor. In many environments, the relationship between moisture content and emissive wavelength …
Date: December 2023
Creator: Farvid, Seyedmajid
System: The UNT Digital Library

Promoting Women? Causes and Effects of Gender-Informed Transitional Justice

Quantitative research investigating the causes and subsequent impact of transitional justice practices has further developed thanks to the production of cross-national data on justice practices, namely by the Justice Data Project and the Transitional Justice Research Collaborative. Current work, however, does not consider the role of justice from a feminist perspective. For example, with respect to causes, we know little about whether and how justice processes are gender inclusive, and what the factors lead to gendered inclusion within justice practices. There is also a need for further inquiry to explain how gendered conflict violence, e.g., sexual violence directed at women, influences justice adoption, and if so, whether these justice processes are more likely to be inclusive of women and gendered issues. Regarding justice impact (its post-hoc effects), there is much to know about the implications gendered justice pose for post-violence societies. Moving away from essentialist notions that position men as protectors and women as inherently peaceful and mere victims of abuse, feminist scholars advocate for research to showcase women's agency as security providers in peacebuilding and peacemaking. I introduce a framework to explain how women and gendered issues become integrated into justice practices and evaluate implications that result from these …
Date: December 2023
Creator: Roark, Polly DeAnne
System: The UNT Digital Library
The Local Organization of Refugee Service Provision: A Qualitative Comparison of Two Resettlement Cities in Texas (open access)

The Local Organization of Refugee Service Provision: A Qualitative Comparison of Two Resettlement Cities in Texas

This comparative case study examines the organizational variations in refugee services in Dallas and Amarillo, Texas. Engaging sociological theories of organizations, migration, and the state, this study conceptualizes immigrant-serving organizations as brokers that operate within fields of similar entities that channel resources and services to refugees. Drawing on 60 in-depth interviews and over two hundred hours of participant observation, this study finds two distinct models of resource brokerage. In Dallas, immigrant-serving organizations operated as networked resource brokers, characterized by high levels of collaboration, robust local political support, and community engagement through consistent volunteer labor. These characteristics facilitated the sharing of resources and knowledge, resulting in the establishment of more professionalized services for immigrants and refugees. In contrast, immigrant-serving organizations in Amarillo operated as atomized resource brokers, characterized by fragmented collaborations, inter-organizational competition, limited volunteer labor, and varying levels of political support from local representatives. This atomized brokerage model hindered the efficient allocation of resources and support, leading to fragmented and less comprehensive services for refugees. In conclusion, this study provides valuable insights into the variations within the organizational fields of ISOs in Texas. The comparative analysis of Dallas and Amarillo offers a nuanced understanding of the impact of local context …
Date: December 2023
Creator: Fessenden, Deborah June
System: The UNT Digital Library

The Effect of Online Consumer Reviews and Brand Equity on the Consumer Decision Making Process

This research aims to investigate the (1) review effects on consumer decision making process, (2) effects of negative reviews on brand equity, and (3) consumers' likely response to a brand's request for reviews. The objective of the first essay is to investigate the nature of the relationship between skepticism and consumer decision making in an online behavior context. Its second objective is to know whether people's belief on their abilities or their hedonic principle moderates the relationship between a person's skepticism toward online reviews and their reliance on online reviews. The objective of the second essay is to explore whether negative online reviews that focus on service quality specific dimensions have a different effect on a service organization's perceived brand equity. Its second objective is to analyze the role of emotional contagion in the relationship between negative reviews related to various service quality dimensions and its effect on perceived brand equity. The main objective of the third essay is to know whether consumers are more likely to write an online review for a brand when the request comes from a higher equity brand. This essay also investigates how message trust and persuasion knowledge influence the relationship between a brand's request …
Date: December 2021
Creator: Ahmad, Fayez
System: The UNT Digital Library

Optimal Pair-Trading Decision Rules for a Class of Non-Linear Boundary Crossings by Ornstein-Uhlenbeck Processes

The most useful feature used in finance of the Ornstein-Uhlenbeck (OU) stochastic process is its mean-reverting property: the OU process tends to drift towards its long- term mean (its equilibrium state) over time. This important feature makes the OU process arguably the most popular statistical model for developing best pair-trading strategies. However, optimal strategies depend crucially on the first passage time (FPT) of the OU process to a suitably chosen boundary and its probability density is not analytically available in general. Even for crossing a simple constant boundary, the FPT of the OU process would lead to crossing a square root boundary by a Brownian motion process whose FPT density involves the complicated parabolic cylinder function. To overcome the limitations of the existing methods, we propose a novel class of non-linear boundaries for obtaining optimal decision thresholds. We prove the existence and uniqueness of the maximizer of our decision rules. We also derive simple formulas for some FPT moments without analytical expressions of its density functions. We conduct some Monte Carlo simulations and analyze several pairs of stocks including Coca-Cola and Pepsi, Target and Walmart, Chevron and Exxon Mobil. The results demonstrate that our method outperforms the existing procedures.
Date: December 2021
Creator: Tamakloe, Emmanuel Edem Kwaku
System: The UNT Digital Library

A New Class of Stochastic Volatility Models for Pricing Options Based on Observables as Volatility Proxies

One basic assumption of the celebrated Black-Scholes-Merton PDE model for pricing derivatives is that the volatility is a constant. However, the implied volatility plot based on real data is not constant, but curved exhibiting patterns of volatility skews or smiles. Since the volatility is not observable, various stochastic volatility models have been proposed to overcome the problem of non-constant volatility. Although these methods are fairly successful in modeling volatilities, they still rely on the implied volatility approach for model implementation. To avoid such circular reasoning, we propose a new class of stochastic volatility models based on directly observable volatility proxies and derive the corresponding option pricing formulas. In addition, we propose a new GARCH (1,1) model, and show that this discrete-time stochastic volatility process converges weakly to Heston's continuous-time stochastic volatility model. Some Monte Carlo simulations and real data analysis are also conducted to demonstrate the performance of our methods.
Date: December 2021
Creator: Zhou, Jie
System: The UNT Digital Library
"Scent of Ink": A Study and Performance Guide of Selected Gagok by Wonju Lee (open access)

"Scent of Ink": A Study and Performance Guide of Selected Gagok by Wonju Lee

Wonju Lee (b. 1979) has already made her own unique contribution to Korean art song. Her songs commissioned by classical Korean music performers have been recorded and released on record labels such as Universal Music and Sony Music. Albums include the Gagok collection, Lee Hwa-woo, The Pear Blossom Falls published by Soo Moon Dang. Some songs have been published by music publishers in the United States such as Classical Vocal Reprints and in Korea by the Korean Traditional Music Resource Center. Wonju Lee's songs are being performed by singers not only in Korea but also in the United States. This study provides information regarding the history of Gagok (Korean art songs) and discusses two duets "Scent of Ink" and "Under the Cherry Tree," and three solo songs "Sam-Arirang," "Relationship," and "Loom Song" by Wonju Lee. This critical essay includes biographical information about the composer and poets, IPA transcriptions for each song, and both word-for-word and poetic translations. In addition, using the methodology from Carol Kimball's book Song: A Guide to Art Song Style and Literature, style sheets of musical characteristics for each song and for the composer are provided and serve as the basis for interpretive recommendations for performers.
Date: May 2022
Creator: Lee, Eun Kyung
System: The UNT Digital Library