Increasing ubiquity of computational resources has enabled simulation of complex electronic systems and modern materials. The PAOFLOW software package is a tool designed to construct and analyze tight binding Hamiltonians from the solutions of DFT calculations. PAOFLOW leverages localized basis sets to greatly reduce computational costs of post-processing QE simulation results, enabling efficient determination of properties such as electronic density, band structures in the presence of electric or magnetic fields, magnetic or spin circular dichroism, spin-texture, Fermi surfaces, spin or anomalous Hall conductivity (SHC or AHC), electronic transport, and more. PAOFLOW's broad functionality is detailed in this work, and several independent studies where PAOFLOW's capabilities directly enabled research on promising candidates for ferroelectric and spintronic based technologies are described. Today, Quantum computers are at the forefront of computational information science. Materials scientists and quantum chemists can use quantum computers to simulate interacting systems of fermions, without having to perform the iterative methods of classical computing. This dissertation also describes a study where the band structure for silicon is simulated for the first time on quantum hardware and broadens this concept for simulating band structures of generic crystalline structures on quantum machines.

Digital language archives are used for the preservation of documented language data, such as video and voice recordings, transcriptions, survey data, and ethnographic fieldnotes. This data is most often used for research and linguists and anthropologists are generally heavily involved in the creation of language archives. Ideally, Indigenous communities that are represented in the archives are also able to access their data, but this is not always the case, especially if poor internet access and lack of technological know-how prevent archive use. In addition, western epistemologies are embedded in archival logics, exacerbating the issues surrounding Indigenous access and pointing to the need for a decolonizing archival design that centers the needs of its users. Using ethnographic research methods and a decolonizing framework, I conducted a usability study on the Archive of the Indigenous Languages of Latin America (AILLA) to uncover the cultural-based meanings that inform AILLA use. Using linguistics and anthropology listservs, I recruited research participants for a Qualtrics survey and conducted semi-structured interviews that explore the user perspective on AILLA. I analyzed AILLA's Google Analytics data and used qualitative and quantitative research methods to build upon the previous literature in user-centered design approaches to language archives. As one of …

Postlingually deafened cochlear implant (CI) adults have large variability in speech perception abilities. While CIs are one of the most successful neural prosthetic devices, they are not able to adequately provide fine structure cues which results in a degraded signal for the listener to interpret. While behavioral measures remain the gold standard for determining speech perception abilities, an objective measure is needed for patients who are unable to provide reliable behavioral responses. Behavioral, cognitive, and neural measures were collected in this study to identify potential neural biomarkers that correlate with speech perception performance. Behavioral experiments evaluated participants' abilities to identify, discriminate, and recognize words as well as sentences in quiet and in noise. Cognitive measures were assessed to determine the roles of attention, impulse control, memory, and cognitive flexibility on speech recognition. Auditory event-related potentials (ERP) were obtained with a double oddball paradigm to produce the mismatch negativity (MMN) response, which has been shown to have associations with phonetic categorical perception at the group level. The results indicated that executive function is highly predictive of speech performance and that the MMN is associated with categorical perception at the individual level. These findings are clinically relevant to determining appropriate follow-up care …

Disaster science is a procedural field often construed as producing blanket policies that attempt to cover everyone, but the complexity of human lived experiences must have a space to exist within disaster science if its research and findings are to be effective. This thesis illustrates that disaster policies and publications often leave out the most vulnerable communities—those in greatest need of collective support. Through critically analyzing beautification through green space, discussing photovoice interviews, and by deconstructing public preparedness documents published by Harris County Office of Homeland Security and Emergency Management (HCOHSEM), it is clear that accumulation by dispossession filters down through not only property and money but also access to green spaces and a healthy life. By dispossessing low-income communities of their right to green spaces and life, those communities end up in places that are environmentally dangerous, leaving them at a disadvantage in the disaster preparedness and recovery process. This thesis serves as a case study highlighting how HCOHSEM failed to provide low-income communities with assistance prior to, during, and after Hurricane Harvey. The lessons from these gaps in protective measures show that public policies need to be malleable to ensure residents of any community are covered. Though no …

This dissertation presents novel approaches to test context aware applications that suffer from a cost prohibitive number of context and GUI events and event combinations. The contributions of this work to test context aware applications under test include: (1) a real-world context events dataset from 82 Android users over a 30-day period, (2) applications of Markov models, Closed Sequential Pattern Mining (CloSPAN), Deep Neural Networks- Long Short Term Memory (LSTM) and Gated Recurrent Units (GRU), and Conditional Random Fields (CRF) applied to predict context patterns, (3) data driven test case generation techniques that insert events at the beginning of each test case in a round-robin manner, iterate through multiple context events at the beginning of each test case in a round-robin manner, and interleave real-world context event sequences and GUI events, and (4) systematically interleaving context with a combinatorial-based approach. The results of our empirical studies indicate (1) CRF outperforms other models thereby predicting context events with F1 score of about 60% for our dataset, (2) the ISFreqOne that iterates over context events at the beginning of each test case in a round-robin manner as well as interleaves real-world context event sequences and GUI events at an interval one achieves …

In this study, I analyze the relationship between sexual permissiveness and affiliation with a fundamentalist religion and how this relationship has changed over time. I first consider previous research that reviews how religious affiliation, religiosity, and religious fundamentalism shapes sex attitudes and, therefore sexual permissiveness. I then review existing studies that discuss what factors influence permissiveness toward different sexual behaviors. Next, I discuss the mechanisms of religious institutions that influence sexual permissiveness. Prior literature motivates my research question as there is a lack of studies that explore sexual permissiveness across religious affiliations. This study fills a void in the existing literature by exploring the gap in sexual permissiveness between religious affiliations and how that gap has changed over time. After considering the current literature, I introduce a hypothesis exploring the relationship between sexual permissiveness and affiliation with fundamentalist religion. This study performs OLS regression using secondary data from the General Social Survey (GSS) that describes respondents' religiosity, religious affiliation, and attitudes towards sex. The study's findings show that affiliation with more fundamentalist groups is significantly correlated with more conservative sex attitudes reflecting lower levels of sexual permissiveness. The results also suggest that the gap in sexual permissiveness between those that …

This study was a replication and an extension of the 2021 research performed by Spurgin and Borquez on the correspondence between receptive and expressive behavior. Spurgin examined the role of the echoic in a hear-say procedure with adult learners, while Borquez examined the role of the echoic in both hear-say and see-say procedures. Both studies found that receptive and expressive correspondence did not occur consistently across participants. The present study asked if the fading steps used during training contributed to the results of the previous researchers. In the present study, the fading steps were changed to minimize the chance that the participant developed a position bias. The conditions were also counterbalanced to analyze the effects of hear-say vs. see-say, easy vs. difficult words, and the order in which the words were trained on the acquisition of receptive labels and the emergence of expressive labels. The study consisted of five phases: pre-training, hear-say teaching, see-say teaching, receptive testing, and expressive testing. Results indicated that although that acquisition of receptive labels improved, the change in fading steps did not make a significant difference in the correspondence of receptive and expressive language. Results showed similar correspondence in the hear-say and see-say procedures. Easy …

The American Clarinet School includes approaches to clarinet playing from European immigrants who instilled their musical style and ideas in the first generation of American-born clarinetists. Some of the first influential pedagogues from Europe include Daniel Bonade (1896-1976), Gustave Langenus (1883-1957), Gaston Hamelin (1884-1951), and Simeon Bellison (1881-1953). Even though they inspired many ideas of the American approach to clarinet, they were known in their time as performers rather than teachers first. The aim of this dissertation is to provide further examination into the modern clarinet professorship in the United States by examining three of the first generation of American-born clarinet professors and their contributions to pedagogy: Keith Stein (1908-1980), William Stubbins (1911-1975), and Himie Voxman (1912-2011). Topics discussed include embouchure, hand position, articulation, technique, expression and phrasing, equipment, teaching beginners, and repertoire.

This was a mixed-method user-centered study regarding the University of North Texas's student-owned learner record and credentialing system. Through methods of quantitative and qualitative inquiry, student perceptions were unearthed and recommendations to improve the system were provided.

This research explores the relationship between narrative, empathy and anxiety in art museum education. The study begins from my personal experience with anxiety and is methodologically rooted in narrative inquiry and friendship as method. In this study, I propose a creative method of narrative postcard writing called (fe)mail – rooted in a feminist ethic of care that seeks to understand and empathize with the experience of others through correspondence. This research asks relevant questions about the future of art museum programming for mental illness and the act of writing (fe)mail as a reflective practice for academics and educators in the field of social science. In my narrative analysis of the program and the data, I also problematizes my role as researcher, educator and friend throughout the study by considering my own biases, expectations and personal educator agenda. The study is divided into two parts. The first comprises correspondence and analysis of (fe)mail between myself and my best friend/co-participant, Atleigh. In Part I, I conduct a narrative analysis of the (fe)mail data produced between us in order to answer the following questions: What qualities of (fe)mail will appear in the exchange? Can (fe)mail be used as a tool for self-care during …

The main research objective of this dissertation is to understand the sensing and communication challenges to achieving cooperative perception among autonomous vehicles, and then, using the insights gained, guide the design of the suitable format of data to be exchanged, reliable and efficient data fusion algorithms on vehicles. By understanding what and how data are exchanged among autonomous vehicles, from a machine learning perspective, it is possible to realize precise cooperative perception on autonomous vehicles, enabling massive amounts of sensor information to be shared amongst vehicles. I first discuss the trustworthy perception information sharing on connected and autonomous vehicles. Then how to achieve effective cooperative perception on autonomous vehicles via exchanging feature maps among vehicles is discussed in the following. In the last methodology part, I propose a set of mechanisms to improve the solution proposed before, i.e., reducing the amount of data transmitted in the network to achieve an efficient cooperative perception. The effectiveness and efficiency of our mechanism is analyzed and discussed.

English learners (ELs) are the fastest growing student group in U.S. public schools. The purpose of this mixed method study was to gain an understanding of the relationship between principal actions and the academic achievement of ELs to determine which practices had the greatest impact on student achievement using archival achievement data. A mixed methods research study was conducted in an urban school district in North Texas to explore differences between principals of schools with high and non-high performance of ELs as it related to the implementation of leadership practices and social justice principles. The principals in the PK-5 grade level band who participated in an online survey, reported statistically significant differences regarding the implementation of leadership practices in the areas of leading student culture and data-driven instruction. Statistically significant differences were also found in the competency of driving for results within the social justice principles. Further data analysis of interview findings revealed the distinction between the high-performing and non-high-performing group to be centered on principal actions as inputs for effective teaching as it related to the implementation of schoolwide systems and processes. Further research is recommended to continue the identification of best practices that support the academic success of …

Broadly defined, group testing is the study of finding defective items in a large set. In the medical infection setting, that implies classifying each member of a population as infected or uninfected, while minimizing the total number of tests.

Historical dress as a museum theater and research process encompasses material, technological, and cultural experiences from the past in the present. This research examines how intimate experiences with heritage materials, processes, and environments may impact development of educator pedagogy. Historical attractions in the US draw visitors due in part to providing guests with context for the objects and built environments displayed. New Materialist theory offers insights into how inanimate objects and environments "teach" human and non-human entities in their own right. Using a New Materialist lens, I observed, interviewed, and conducted participant observations through a novel research methodology, intra-active narrative inquiry, with costumed museum educators to better discern how relations between humans and historical materials intra-act as embodied experiences of object knowledge in museum pedagogy.

This work demonstrates how local, randomized tailoring of bond stiffness can affect the activation energy of diffusion in model alloys using density functional theory-based computations. This work is organized into two parts. The first part deals with the vacancy diffusion mechanism, and it compares the in–plane (IP) vs out-of-plane (OOP) diffusion paths in prototypical binary Mg-X (Ca, Y, and Gd) and ternary Mg-X (Ca, Y, and Gd)-Zn alloys. We examine how vacancy formation, migration, and solute vacancy binding energies in binary Mg-X alloys influence diffusion activation and correlated them with conventional diffusion model based solely on the solute sizes. Next, we explore how Zn addition to binary Mg-X (Ca, Y, and Gd) alloys influences the OOP activation energy barrier is discussed in terms of detailed energetic computations and bond characterization in the present work. Our results indicate that Zn addition further enhances the OOP activation energy barrier compared to corresponding activation energies in Mg binaries. This work concludes that engineering stiffer directional bonds via micro-alloying additions in Mg is a promising route to dramatically improve their high temperature creep response. The second part of my work investigates the effects of Si, P, and S solutes on H interstitial diffusion mechanism …

Molecular dynamics simulations and QM/MM calculations can provide insights into the structure and function of enzymes as well as changes due to mutations of the protein sequence.

By organically fusing the methods of convolutional neural network (CNN) and recurrent neural network (RNN), this dissertation focuses on the application of optical character recognition and image classification processing. The first part of this dissertation presents an end-to-end novel receipt recognition system for capturing effective information from receipts (CEIR). The main contributions of this research part are divided into three parts. First, this research develops a preprocessing method for receipt images. Second, the modified connectionist text proposal network is introduced to execute text detection. Third, the CEIR combines the convolutional recurrent neural network with the connectionist temporal classification with maximum entropy regularization as a loss function to update the weights in networks and extract the characters from receipt. The CEIR system is validated with the scanned receipts optical character recognition and information extraction (SROIE) database. Furthermore, the CEIR system has strong robustness and can be extended to a variety of different scenarios beyond receipts. For the convolutional recurrent structure application of land use image classification, this dissertation comes up with a novel deep learning model for land use classification, the convolutional recurrent land use classifier (CRLUC), which further improves the accuracy in classifying remote sensing land use images. Besides, the …

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.

Multiple contributors to neurocognitive impairment in individuals with sickle cell disease have been identified. Research indicates that a history of cerebrovascular accidents, such as silent infarcts and strokes are associated with greater cognitive decline among children with sickle cell disease. Additionally, disease effects such as hemoglobin and hematocrit levels significantly effect cognitive performance among this population and should be taken into consideration when examining neurocognitive impairment. Further, previous studies show a significant relationship between child behavior problems, family functioning, and cognitive performance in children with sickle cell, marking those as important targets for intervention among this population. While cognitive decline with increased age is not typically examined in healthy child populations, some research indicates the presence of age effects in those with SCD. A majority of the literature addresses cognitive impairment from a broad perspective, while a limited number of studies have begun to address effects among specific cognitive domains. Using archival data from the National Institutes of Health's Cooperative Study of Sickle Cell Disease, results revealed that disease severity was negatively correlated with some aspects of cognitive functioning, including visual-spatial domains. Additionally, some measures of cognitive performance were inversely correlated with age. Consistent with hypothesized outcomes, family functioning was …

A projective plane tropical curve is a proper immersion of a graph into the real Cartesian plane subject to some conditions such as that the images of all the edges must be lines with rational slopes. Two important combinatorial invariants of a projective plane tropical curve are its degree, d, and genus g. First, we explore Gathmann and Markwig's approach to the study of the moduli spaces of such curves and explain their proof that the number of projective plane tropical curves, counting multiplicity, passing through n = 3d + g -1 points does not depend on the choice of points, provided they are in tropical general position. This number of curves is called a Gromov-Written invariant. Second, we discuss the proof of a theorem of Mikhalkin that allows one to compute the Gromov-Written invariant by a purely combinatorial process of counting certain lattice paths.

Low Earth orbit (LEO) satellite systems have been proposed as a resource for combating the challenges in 5G network coverage and expanding connectivity to a global realm. This research focuses on the current architecture of LEO satellite constellations, with an emphasis on satellite coverage, visibility patterns and coordination schemes. Key-elements of integrating LEO satellites into the eMBB component of 5G are presented and a breakdown of potential link channel characteristics and physical layer performance metrics are described. The produced information allows for a justified analysis on the conceptualized integration.

Photograph of a variety of scattered handwritten notes and drawings including edited pages of drafts, academic and personal notes, recipes, and sheet music from the James Flowers Collection of Ephemera Found in Returned Library Books held by UNT Special Collections.

Photograph of a variety of lined up library book check out cards from the James Flowers Collection of Ephemera Found in Returned Library Books held by UNT Special Collections.

Photograph of a variety of lined up business cards from the James Flowers Collection of Ephemera Found in Returned Library Books held by UNT Special Collections.