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Toward Leveraging Artificial Intelligence to Support the Identification of Accessibility Challenges

The goal of this thesis is to support the automated identification of accessibility in user reviews or bug reports, to help technology professionals prioritize their handling, and, thus, to create more inclusive apps. Particularly, we propose a model that takes as input accessibility user reviews or bug reports and learns their keyword-based features to make a classification decision, for a given review, on whether it is about accessibility or not. Our empirically driven study follows a mixture of qualitative and quantitative methods. We introduced models that can accurately identify accessibility reviews and bug reports and automate detecting them. Our models can automatically classify app reviews and bug reports as accessibility-related or not so developers can easily detect accessibility issues with their products and improve them to more accessible and inclusive apps utilizing the users' input. Our goal is to create a sustainable change by including a model in the developer's software maintenance pipeline and raising awareness of existing errors that hinder the accessibility of mobile apps, which is a pressing need. In light of our findings from the Blackboard case study, Blackboard and the course material are not easily accessible to deaf students and hard of hearing. Thus, deaf students …
Date: May 2023
Creator: Aljedaani, Wajdi Mohammed R M., Sr.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Electronic Health Record Systems and Cyber Hygiene: Awareness, Knowledge, and Practices among Physicians in Kuwait (open access)

Electronic Health Record Systems and Cyber Hygiene: Awareness, Knowledge, and Practices among Physicians in Kuwait

This study explored issues related to the adoption and implementation of electronic health record (EHR) systems including building the awareness, knowledge, and experience of physicians toward cyber hygiene. This study used a qualitative research method to assess (a) the barriers to EHR systems adoption and implementation in Kuwait and (b) the level of awareness, knowledge and experiences related to cyber hygiene practices in Kuwait. The findings of the study supported the conceptual framework used to guide the research of the factors impacting the adoption and implementation of EHR systems in Kuwait as well as explore the level of awareness, knowledge, and experience of physicians about both EHR systems and cyber hygiene. The results from the systematic literature review analysis identified seven major barriers. These are financial barriers, time, difficulty of using technology, lack of support, negative attitude, legal and ethical (policies), and cultural barriers. The findings from the semistructured interviews supported the literature findings and provided more in-depth insights into the structural and social issues affecting the adoption and implementation of EHR systems. Given that Kuwait is a member of the Gulf Cooperation Countries (GCC), the results from the literature analysis showed that the problems in Kuwait are similar to …
Date: December 2022
Creator: Alkhaledi, Reem
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Scalable Next Generation Blockchains for Large Scale Complex Cyber-Physical Systems and Their Embedded Systems in Smart Cities (open access)

Scalable Next Generation Blockchains for Large Scale Complex Cyber-Physical Systems and Their Embedded Systems in Smart Cities

The original FlexiChain and its descendants are a revolutionary distributed ledger technology (DLT) for cyber-physical systems (CPS) and their embedded systems (ES). FlexiChain, a DLT implementation, uses cryptography, distributed ledgers, peer-to-peer communications, scalable networks, and consensus. FlexiChain facilitates data structure agreements. This thesis offers a Block Directed Acyclic Graph (BDAG) architecture to link blocks to their forerunners to speed up validation. These data blocks are securely linked. This dissertation introduces Proof of Rapid Authentication, a novel consensus algorithm. This innovative method uses a distributed file to safely store a unique identifier (UID) based on node attributes to verify two blocks faster. This study also addresses CPS hardware security. A system of interconnected, user-unique identifiers allows each block's history to be monitored. This maintains each transaction and the validators who checked the block to ensure trustworthiness and honesty. We constructed a digital version that stays in sync with the distributed ledger as all nodes are linked by a NodeChain. The ledger is distributed without compromising node autonomy. Moreover, FlexiChain Layer 0 distributed ledger is also introduced and can connect and validate Layer 1 blockchains. This project produced a DAG-based blockchain integration platform with hardware security. The results illustrate a practical technique …
Date: July 2023
Creator: Alkhodair, Ahmad Jamal M
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Interorganizational Collaboration in Implementing Urban Greening Policies in Saudi Arabia: An Institutional Collective Action Framework

This dissertation aims to examine the relationship between interorganizational collaboration and the implementation of urban greening policy. Specifically, it discusses bonding and bridging relationships that explain a successful interorganizational collaboration, and to what extent these factors explain the perception of success in the implementation of public programs. The effects of risks of collaboration on the implementation of urban greening policy are also studied. To frame the analysis, this dissertation uses Feiock's institutional collective action (ICA) framework, which aims to understand successful interorganizational collaboration and policy implementation across sectors. The collection of data was carried out in Riyadh City in Saudi Arabia, which is located in the center of Saudi Arabia. In this study, the unit of analysis is the networks of relationships among organizations that work with the Royal Commission for Riyadh City (RCRC). The data were obtained from 44 organizations collaborating to implement urban greening projects in Riyadh City and were collected over 17 days from June 15, 2019 to July 2, 2019. The sampling technique used in this study was snowball sampling. The main statistical methods employed for hypothesis examination were social network analysis (SNA) and ordinary least squares (OLS). The key empirical results indicated that there were …
Date: May 2020
Creator: Alkhurayyif, Mohammed A.
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Third-Party Perception: Implications for Governance and Communication of Health Risks during the Umrah in Saudi Arabia

The current study projects the third-person perception phenomenon into the area of emergency management, specifically regarding risk communication in the context of religious gatherings. This study utilized the Umrah religious gathering in Makkah, Saudi Arabia, during summer 2019 as a case study (N = 257). This study aimed to investigate whether pilgrims perceive there was a greater effect of health information on others than on themselves. Survey results were translated and then coded and analyzed statistically using SPSS software. The findings indicated that third-person perception existed among pilgrims. Specifically, the perception of pilgrims that the influence of news about MERS-CoV, believed to be undesirable in its effect on themselves, was greater on others than on themselves was found statistically significant. Further, the findings indicated that the more pilgrims watched, listened to, or read news about MERS-CoV, the larger the effect of the news they perceived on themselves and others was. Thus, exposure to MERS-CoV news did not increase, but rather decreased the perception of difference between self and others. Also, the empirical findings indicated that pilgrims who were knowledgeable about MERS-CoV could relate to the coverage. Moreover, if pilgrims believed they were affected by MERS-CoV news, they believed that the …
Date: May 2020
Creator: Alkhurayyif, Saad A.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
FruitPAL: An IoT-Enabled Framework for Automatic Monitoring of Fruit Consumption in Smart Healthcare (open access)

FruitPAL: An IoT-Enabled Framework for Automatic Monitoring of Fruit Consumption in Smart Healthcare

This research proposes FruitPAL and FruitPAL 2.0. They are full automatic devices that can detect fruit consumption to reduce the risk of disease. Allergies to fruits can seriously impair the immune system. A novel device (FruitPAL) detecting fruit that can cause allergies is proposed in this thesis. The device can detect fifteen types of fruit and alert the caregiver when an allergic reaction may have happened. The YOLOv8 model is employed to enhance accuracy and response time in detecting dangers. The notification will be transmitted to the mobile device through the cloud, as it is a commonly utilized medium. The proposed device can detect the fruit with an overall precision of 86%. FruitPAL 2.0 is envisioned as a device that encourages people to consume fruit. Fruits contain a variety of essential nutrients that contribute to the general health of the human body. FruitPAL 2.0 is capable of analyzing the consumed fruit and then determining its nutritional value. FruitPAL 2.0 has been trained on YOLOv5 V6.0. FruitPAL 2.0 has an overall precision of 90% in detecting the fruit. The purpose of this study is to encourage fruit consumption unless it causes illness. Even though fruit plays an important role in people's …
Date: December 2023
Creator: Alkinani, Abdulrahman Ibrahim M.
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Inflammatory Biomarker Levels and Vaccine Response

This study was conducted as part of a parent grantwhich examined the relationship between components of sleep and antibody responses to the flu vaccine in a population of 392 nurses working at two large hospitals. During/after sleep data was collected, nurses had blood drawn at four time points: immediately pre-vaccination, 1-, 6-, and 11-months post vaccine to obtain serum for detection of anti-influenza antibodies measured with an HI (hemagglutination inhibition) assay. Additionally, the inflammatory biomarkers IL6, IL1-β, TNF-α and CRP were measured at the pre-vaccine time point only to determine any correlation between the markers and antibody response. Data was analyzed using a hierarchical regression. In the first step, analyses assessed whether each change/average in cytokines over the one-month period had an impact on vaccine response for each of the four viral strains in the flu vaccine. In a second step, analyses assessed whether variables such as insomnia, stress, age, smoking, BMI, and race had any impact on vaccine response beyond the effects exerted through inflammation. The change in association (β) between the primary independent variable and primary dependent variable were examined in order to determine whether there are any suppression effects caused by baseline covariates on the relationship between …
Date: May 2022
Creator: Alkire, Christopher B
Object Type: Thesis or Dissertation
System: The UNT Digital Library

The Impact of Including Teacher and School Characteristics on Predicting Value-Added Score Estimates

Value-added models (VAMs) have become widely used in evaluating teacher accountability. The use of these models for high-stakes decisions making has been very controversial due to lack of consistency in classifying teachers as high performing or low performing. There is an abundance of research on the impact of various student level covariates on teacher value-added scores; however, less is known about the impact of teacher-level and school-level covariates. This study uses hierarchical linear modeling to examine the impact of including teacher characteristics, school characteristics, and student demographics aggregated at the school level on elementary mathematics and reading teacher value-added scores. Data for this study was collected from a large school district in north Texas. This study found that across all VAMs fitted, 32% of mathematics teachers and 37% of reading teachers changed quintile ranking for their value-added score at least once across all VAMs, while 55% and 65% of schools changed their quintile ranking of value-added scores based on mathematics and reading achievement, respectively. The results show that failing to control for aggregated student demographics has a large impact on both teacher level and school level value-added scores. Policymakers and administrators using VAM estimates in high-stakes decision-making should include teacher- …
Date: May 2021
Creator: Allen, Lauren E.
Object Type: Thesis or Dissertation
System: The UNT Digital Library

My Darling Boys: A Family at War, 1941-1947

Access: Use of this item is restricted to the UNT Community
My Darling Boys is the story of a New Mexico farm family whose three sons were sent to fight in World War II. All flew combat aircraft in the Army Air Forces. In 1973 one of the boys, Oscar Allison, a B-24 top turret gunner and flight engineer, wrote a memoir of his World War II experiences. On a mission to Regensburg, Germany, his bomber, ravaged by German fighters, was shot down. He was captured and spent fifteen months in German stalag prisons. His memoir, the core of this unique book, details his training, combat, and prisoner-of-war experience in a truthful, introspective, and compelling manner. Fred H. Allison, the author and Oscar’s nephew, gained access to family letters that supplement Oscar’s story and bring to light the experiences of Oscar’s brothers. Harold Allison, the author’s father, was sidelined from combat as a bomber copilot due to a health condition. The letters also tell of the brother who did not come home, Wiley Grizzle Jr., a P-51 fighter pilot. Wiley’s last mission brought his squadron of Mustangs into a pitched battle with German fighters bound for the front to attack American troops. The letters also introduce the boys’ family, who fought …
Date: October 2023
Creator: Allison, Fred H.
Object Type: Book
System: The UNT Digital Library
Thermal Transport Modeling in Three-Dimensional Pillared-Graphene Structures for Efficient Heat Removal (open access)

Thermal Transport Modeling in Three-Dimensional Pillared-Graphene Structures for Efficient Heat Removal

Pillared-graphene structure (PGS) is a novel three-dimensional structure consists of parallel graphene sheets that are separated by carbon nanotube (CNT) pillars that is proposed for efficient thermal management of electronics. For microscale simulations, finite element analyses were carried out by imposing a heat flux on several PGS configurations using a Gaussian pulse. The temperature gradient and distribution in the structures was evaluated to determine the optimum design for heat transfer. The microscale simulations also included conducting a mesh-independent study to determine the optimal mesh element size and shape. For nanoscale simulations, Scienomics MAPS software (Materials And Processes Simulator) along with LAMMPS (Large-scale Atomic/ Molecular Massively Parallel Simulator) were used to calculate the thermal conductivity of different configurations and sizes of PGS. The first part of this research included investigating PGS when purely made of carbon atoms using non-equilibrium molecular dynamics (NEMD). The second part included investigating the structure when supported by a copper foil (or substrate); mimicking production of PGS on copper. The micro- and nano-scale simulations show that PGS has a great potential to manage heat in micro and nanoelectronics. The fact that PGS is highly tunable makes it a great candidate for thermal management applications. The simulations were …
Date: December 2020
Creator: Almahmoud, Khaled Hasan Musa
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Design Optimization of Functionalized Silica-Polymer Nanocomposite through Finite Element and Molecular Dynamics Modeling (open access)

Design Optimization of Functionalized Silica-Polymer Nanocomposite through Finite Element and Molecular Dynamics Modeling

This dissertation focuses on studying membrane air dehumidification for a membrane moisture exchanger in a membrane heat pump system. The study has two parts: an optimization of membrane moisture exchanger for air dehumidification in the macroscale, and diffusion of water vapor in polymer nanocomposites membrane for humid air dehumidification in the nanoscale. In the first part of the research, the mass transport of water vapor molecules through hydrophilic silica nanochannel chains in hydrophobic polyurethane matrix was studied by simulations and experiments for different membrane moisture exchanger design configurations. The mass transport across the polymer nanocomposite membrane occurs with the diffusion of moist air water vapor molecules in the membrane moisture exchanger in a membrane heat pump air conditioning system for air dehumidification purposes. The hydrophobic polyurethane matrix containing the hydrophilic silica nanochannel chains membrane is responsible for transporting water vapor molecules from the feed side to the permeate side of the membrane without allowing air molecules to pass through.In the second part of the research, diffusion analysis of the polymer nanocomposite membrane were performed in the nanoscale for the polymer nanocomposite membrane. The diffusion phenomena through the polymer, the polymer nanocomposite without modifying the silica surfaces, and the polymer nanocomposite …
Date: August 2020
Creator: Almahmoud, Omar H. M.
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Analysis of Multipartite Bacterial Genomes Using Alignment-Free and Alignment-Based Pipelines

In this work, we have performed comparative evolutionary analysis, functional genomics analysis, and machine learning analysis to identify the molecular factors that discriminate between multipartite and unipartite bacteria, with the goal to decipher taxon-specific factors and those that are prevalent across the taxa underlying the these traits. We assessed the roles of evolutionary mechanisms, namely, horizontal gene transfer and gene gain, in driving the divergence of bacteria with single and multiple chromosomes. In addition, we performed functional genomic analysis to garner support for our findings from comparative evolutionary analysis. We found genes such as those encoding conserved hypothetical protein DR_A0179 and hypothetical protein DR_A0109 in Deinococcus radiodurans R1, and Putative phage phi-C31 gp36 major capsid-like protein and hypothetical protein RSP_3729 in Rhodobacter sphaeroides 2.4.1, which are located on accessory chromosomes in both bacteria and were not found in the inferred ancestral sequences, and on the primary chromosomes, as well as were not found in their closest relatives with single chromosome within the same clade. These genes emphasize the important potential roles of the secondary chromosomes in helping multipartite bacteria to adapt to specialized environments or conditions. In addition, we applied machine learning algorithms to predict multipartite genomes based on gene …
Date: August 2021
Creator: Almalki, Fatemah
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Design, Fabrication and Testing of a Novel Dual-Axis Automatic Solar Tracker System Using a Fresnel-Lens Solar Concentrator

This thesis project investigates, analyzes, designs, simulates, constructs and tests a dual-axis solar tracker system to track the sun and concentrates the heat of the sunlight, using a Fresnel lens, into a small area, which is above of an evaporator, to increase the temperature of the seawater to convert it into freshwater. The dual-axis solar tracker was designed with the main objectives that the structure was portable, dismountable, lightweight, low cost, corrosion resistant, wires inside pipes, accurate, small size, follow the sun automatically, off-grid (electrical), use green energy (solar powered), and has an empty area right below of the lens. First, a 500 mm diameter flat Fresnel lens was selected and simulated based on an algorithmic method achieved by a previous PhD student at UNT using MATLAB®, to give the optimization lens dimensions. The lens profile was drawn with AutoCAD®, then output profile lens was simulated in COMSOL Multiphysics®. The objective was to provide the high efficiency, optimum and high precision of the focal rays and heat to the receiver of the evaporator. A novel dual-axis solar tracker system was then designed that is portable, dismountable, lightweight and corrosion resistant. The solar tracker tracks the sun in two axis of …
Date: August 2021
Creator: Almara, Laura Mabel
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Gender Differences, Age Differences, and the Relationship between Time Spent Playing Video Games and Cognitive, Affective, and Behavioral Engagement (open access)

Gender Differences, Age Differences, and the Relationship between Time Spent Playing Video Games and Cognitive, Affective, and Behavioral Engagement

This study quantitatively and qualitatively measured gender and age differences in cognitive, affective, and behavioral engagement while playing video games among the University of North Texas (UNT) undergraduate students. Also, it examined the relationship between time spent playing video games and the three engagement states. For the quantitative method, the data of this study was collected via an online survey, the Consumer Video Game Engagement Scale (CVGES), distributed at UNT (N = 140). The qualitative method involved asking open-ended questions at the end of the survey. The CVGES uses a 5-point Likert scale that encompasses three subscales: (a) Cognitive Engagement, (b) Affective Engagement, and (c) Behavioral Engagement. A series of analyses were conducted to analyze the quantitative data via SPSS. Also, the open-ended questions' responses were analyzed by using an inductive analysis approach. The main findings of this study were: (a) there were significant differences between males and females in cognitive, affective, and behavioral engagement, (b) there were no significant differences between age groups in the three engagement states, and (c) there is a positive relationship between the time spent playing a video game and the three engagement states. Also, the game elements, such as characters, storytelling, content, the objective …
Date: December 2022
Creator: Almazyad, Reem Ali
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Freight Forwarder Satisfaction: A Conceptualization and an Empirical Test of Effect on Airport Customer Loyalty and Competitiveness

In 2018, global gross domestic product (GDP) was US$86.3 trillion, and almost a quarter of that value was due to international trade with a value of US$19.6 trillion. Air cargo accounts for about 35 percent of that trade value (approximately US$6.86 trillion). Moreover, from the perspective of the airport sector, air cargo revenue contributes between 20 to 70 percent of airport revenue. The global airport revenue for freight in 2018 was US$250 billion. Despite the interest and research activities surrounding competition and competitiveness of airports and specifically among airlines and passengers, it appears scholars have overlooked research concerning the competitiveness of airports when it comes to air cargo. This study attempts to fill the gap in the supply chain and logistics literature by putting forward a framework and ultimately operationalizing the framework highlighting the pivotal role of air cargo in the supply chain domain and within the global economy. Specifically, the framework is operationalized within the freight forwarding air cargo supply chain domain – providing insight into this important yet understudied phenomenon. The population of interest is freight forwarders from the Dubai International Airport, United Arab Emirates. The Middle East represents 18 percent of the world's air cargo volume and …
Date: May 2021
Creator: Almofeez, Sarah Ibraheem
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Modeling Email Phishing Attacks (open access)

Modeling Email Phishing Attacks

Cheating, beguiling, and misleading information exist all around us; understanding deception and its consequences is crucial in our information environment. This study investigates deception in phishing emails that successfully bypassed Microsoft 365 filtering system. We devised a model that explains why some people are deceived and how targeted individuals and organizations can prevent or counter attacks. The theoretical framework used in this study is Anderson's functional ontology construction (FOC). The methodology involves quantitative and qualitative descriptive design, where the data source is the set of phishing emails archived from a Tier 1 University. We looked for term frequency-inverse document frequency (Tf-idf) and the distribution of words over documents (topic modeling) and found the subjects of phishing emails that targeted educational organizations are related to finances, jobs, and technologies. Also, our analysis shows the phishing emails in the dataset come under six categories; reward, urgency, curiosity, fear, job, and entertainment. Results indicate that staff and students were primarily targeted, and a list of the most used verbs for deception was compiled. We uncovered the stimuli being used by scammers and types of reinforcements used to misinform the target to ensure successful trapping via phishing emails. We identified how scammers pick their …
Date: December 2021
Creator: Almoqbil, Abdullah
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Twisted Moire Photonic Crystals: Their Nano-Fabrications, Optical Properties, and Applications in Light Extraction

In this dissertation, I report the results of my research on twisted moiré photonic crystals which can be formed through multi-beam holographic interference without a physical rotation and later fabricated by electron-beam lithography. Their optical properties, such as photonic bandgaps, multiple resonance modes, and quality factor are presented. Randomized moire photonic crystals in lattice are also studied. The applications of moire photonic crystals in improving light extraction efficiency are simulated and verified in light emitting devices. Furthermore, I simulated the light extraction efficiency in OLED when the Al layer is patterned with a triangular GPSC, square moiré PhC with defects in the uniform area, and random locations of the photonic lattice, and obtain light extraction efficiency of 78.9%, 79.9%, 81.7%, respectively. Also, the ratios of photoluminescence intensity of LED integrated with twisted moiré PhCs and random moiré PhCs over that without moiré PhCs are measured to be (1.3-1.9) and 1.74, respectively, in a good agreement with simulated ratios of 1.69 and 1.8.
Date: May 2023
Creator: Alnasser, Khadijah Saleh T.
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Frameworks for Attribute-Based Access Control (ABAC) Policy Engineering

In this disseration we propose semi-automated top-down policy engineering approaches for attribute-based access control (ABAC) development. Further, we propose a hybrid ABAC policy engineering approach to combine the benefits and address the shortcomings of both top-down and bottom-up approaches. In particular, we propose three frameworks: (i) ABAC attributes extraction, (ii) ABAC constraints extraction, and (iii) hybrid ABAC policy engineering. Attributes extraction framework comprises of five modules that operate together to extract attributes values from natural language access control policies (NLACPs); map the extracted values to attribute keys; and assign each key-value pair to an appropriate entity. For ABAC constraints extraction framework, we design a two-phase process to extract ABAC constraints from NLACPs. The process begins with the identification phase which focuses on identifying the right boundary of constraint expressions. Next is the normalization phase, that aims at extracting the actual elements that pose a constraint. On the other hand, our hybrid ABAC policy engineering framework consists of 5 modules. This framework combines top-down and bottom-up policy engineering techniques to overcome the shortcomings of both approaches and to generate policies that are more intuitive and relevant to actual organization policies. With this, we believe that our work takes essential steps towards …
Date: August 2020
Creator: Alohaly, Manar
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Participation in the Play of Nature: A Hermeneutic Approach to Environmental Aesthetics (open access)

Participation in the Play of Nature: A Hermeneutic Approach to Environmental Aesthetics

Within the environmental aesthetics literature, there is a noticeable schism between two general approaches to understanding the aesthetic value of nature: the ambient approach and the narrative approach. Ambient thinkers focus on the character of aesthetic appreciation of nature, the way in which one is embedded in multi-sensory environment. These ambient theorists emphasize the importance of those aesthetic experiences that are difficult to articulate. Narrative thinkers argue that aesthetic appreciation of nature is enhanced and enriched by narratives that are relevant to the natural object or environment encountered. Certain narratives – usually those based on scientific knowledge – encourage a depth of appreciation that is inaccessible to those unfamiliar with the narratives. In this dissertation, I attempt to articulate an account of environmental aesthetic experience that does justice to both of these approaches by drawing on the resources of philosophical hermeneutics, and especially on the aesthetic theory of Hans-Georg Gadamer. The most important aspects of Gadamer's work for environmental aesthetics are his phenomenology of play, his revival of practical philosophy, and his emphasis on the interpretive character of all understanding. His discussion of play fleshes out the core of ambient accounts, his focus on interpretation explains the insights of narrative …
Date: December 2020
Creator: Aloi, Michael Joseph
Object Type: Thesis or Dissertation
System: The UNT Digital Library
The Use of Smartphone Applications for Learning Purposes among Saudi Students (open access)

The Use of Smartphone Applications for Learning Purposes among Saudi Students

The purpose of the current study was to confirm or dismiss Saudi students' behavioral intention with regard to using smartphone applications for learning purposes. A quantitative, non-experimental survey research design and descriptive research conducted on the determinants -performance expectancy, effort expectancy, and social influence- that predict Saudi students' intention at University of North Texas to use smartphone applications for learning purposes, based on the unified theory of acceptance and use of technology (UTAUT) as the framework. This study aims at filling gap found in understanding of students' intentions and their behaviors regarding the adoption and use of the Smartphone applications. Data was collected by means of an online questionnaire. The hypothesized model validated empirically using data collected from around 234 Saudi students who enrolled at University of North Texas. The model developed from UTAUT explained 50.1% of the variance of behavioral intention, and behavioral intentions explained 13.6% of the variance of usage behavior. The result of this study support that the determinants of performance expectancy, effort expectancy, and facilitating conditions were the highest predictors of behavioral intentions in using smartphone applications for learning purposes. The results of this study could encourage students, educators, and the Saudi Arabia Ministry of Education …
Date: August 2020
Creator: Alomran, Amal I
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Exploring Factors Affecting Public Service Motivation: An Investigation of Public Service Motivation in Saudi Arabia

This research builds on social exchange theory and self-determination theory to better understand the relationships between employee engagement, demographic and personal attributes, and public service motivation (PSM). It hypothesizes that employee engagement and demographic and personal characteristics (education, income, gender, and parents working in civil service) will directly affect PSM. I also hypothesize that education, income, and gender will have an indirect effect and moderate the relationship between employee engagement and PSM. This dissertation uses a quantitative approach to investigate the hypotheses introduced with the conceptual model. This research uses structural equation modeling as a data analysis technique. Based on 704 valid questionnaires distributed to Saudi public employees in Riyadh, Jeddah, Dammam, and Assir, the analysis shows that a higher level of employee engagement will lead to a higher level of public service motivation. It also reveals that a higher level of education will lead to a higher level of PSM.; the hypothesis that income positively affects PSM is not supported. Thus, this study finds that there is no significant relationship between income and PSM. Being female is found to be negatively associated with PSM. Therefore, the hypothesis that females are lower PSM than males is supported. Parents of public …
Date: May 2021
Creator: Alotaibi, Saud G.
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Social Exchange Theory in the Context of X (Twitter) and Facebook Social Media Platforms with a Focus on Privacy Concerns among Saudi Students

The current research examines the use of social media and its security settings using the Social Exchange Theory (SET) within a Saudi student environment. This research includes an introduction, literature review, methodology, results, and conclusion with the results section presenting the findings from the three essays. The first essay employs the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) methodology of SET. PRISMA's systematic and exhaustive approach to literature evaluation increases the likelihood of obtaining high-quality, reproducible findings. In the second essay, which focuses on awareness of X's (Twitter) security settings, a quantitative research approach was utilized. A sample of former and current Saudi students (graduate and undergraduate) at the University of North Texas participated in the investigation. This research provides an empirical examination of the use of X (Twitter) and its security features within this community by employing statistical analysis of the data from respondents. Likewise, the same sample of Saudi students from the University of North Texas was used for the third essay in which the use of Facebook's security settings was examined. Having a consistent sample across both studies enables a comparison and a greater understanding of the security awareness and practices of this group across …
Date: December 2023
Creator: Alqahtani, Sameer Mohammed S.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Deep Minima and Vortices for Positronium Formation in Positron-Hydrogen and Positron-Helium Collisions (open access)

Deep Minima and Vortices for Positronium Formation in Positron-Hydrogen and Positron-Helium Collisions

This dissertation work is a study of positronium formation for positron-hydrogen and positron-helium collisions in the Ore gap (the energy region between the threshold for ground-state positronium formation and the first excitation level of the target atom) using variational K-matrices. We have fitted the K-matrices using multichannel effective range theories and using polynomials. Using the variational K-matrices and their fits, we have located zeros in the positronium-formation scattering amplitude and corresponding deep minima in the positronium-formation differential cross section. The zeros are related to the vortices in the extended velocity field associated with the positronium-formation scattering amplitude. For positron-hydrogen collisions, we have found two zeros in the positronium-formation scattering amplitude, and corresponding deep minima in the positronium-formation differential cross section, while we have obtained a zero in the positronium-formation scattering amplitude for positron-helium collisions. We have connected the zeros in the positronium-formation scattering amplitude to vortices in the extended velocity fields. Our work shows that vortices can occur for charge exchange in atomic collisions.
Date: May 2021
Creator: Alrowaily, Albandari Wanes
Object Type: Thesis or Dissertation
System: The UNT Digital Library
A Comprehensive Investigation of Photoinduced Electron Transfer and Charge Transfer Mechanisms in Push-Pull Donor-Acceptor Systems: Implications for Energy Harvesting Applications (open access)

A Comprehensive Investigation of Photoinduced Electron Transfer and Charge Transfer Mechanisms in Push-Pull Donor-Acceptor Systems: Implications for Energy Harvesting Applications

Donor-acceptor systems exhibit distinctive attributes rendering them highly promising for the emulation of natural photosynthesis and the efficient capture of solar energy. This dissertation is primarily devoted to the investigation of these unique features within diverse donor-acceptor system typologies, encompassing categories such as closely covalently linked, push-pull, supramolecular, and multi-modular donor- acceptor conjugates. The research encompasses an examination of photosynthetic analogs involving compounds such as chelated azadipyromethene (AzaBODIPY), N,N-dimethylaminophenyl (NND), phenothiazine (PTZ), triphenylamine (TPA), phenothiazine sulfone (PTZSO2), tetracyanobutadiene (TCBD), and expanded tetracyanobutadiene (exTCBD). The strategic configuration of the donor (D), acceptor (A), and spacer elements within these constructs serves to promote intramolecular charge transfer (ICT), which are crucial for efficient charge and electron transfer. The employment of cutting-edge analytical techniques, such as ultrafast transient absorption spectroscopy, is integral to the study. Furthermore, a comprehensive suite of analytical methodologies including steady-state UV-visible absorption spectroscopy, fluorescence and phosphorescence spectroscopies, electrochemical techniques (including cyclic voltammetry and differential pulse voltammetry), spectroelectrochemistry, and density functional theory calculation (DFT), collectively contribute to the comprehensive characterization of push-pull donor-acceptor systems, with a particular emphasis on their potential as highly effective solar energy harvesting application.
Date: December 2023
Creator: Alsaleh, Ajyal Zaki
Object Type: Thesis or Dissertation
System: The UNT Digital Library