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Hybrid Optimization Models for Depot Location-Allocation and Real-Time Routing of Emergency Deliveries (open access)

Hybrid Optimization Models for Depot Location-Allocation and Real-Time Routing of Emergency Deliveries

Prompt and efficient intervention is vital in reducing casualty figures during epidemic outbreaks, disasters, sudden civil strife or terrorism attacks. This can only be achieved if there is a fit-for-purpose and location-specific emergency response plan in place, incorporating geographical, time and vehicular capacity constraints. In this research, a comprehensive emergency response model for situations of uncertainties (in locations' demand and available resources), typically obtainable in low-resource countries, is designed. It involves the development of algorithms for optimizing pre-and post-disaster activities. The studies result in the development of four models: (1) an adaptation of a machine learning clustering algorithm, for pre-positioning depots and emergency operation centers, which optimizes the placement of these depots, such that the largest geographical location is covered, and the maximum number of individuals reached, with minimal facility cost; (2) an optimization algorithm for routing relief distribution, using heterogenous fleets of vehicle, with considerations for uncertainties in humanitarian supplies; (3) a genetic algorithm-based route improvement model; and (4) a model for integrating possible new locations into the routing network, in real-time, using emergency severity ranking, with a high priority on the most-vulnerable population. The clustering approach to solving dept location-allocation problem produces a better time complexity, and the …
Date: May 2021
Creator: Akwafuo, Sampson E
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Collaboration among Conflict Management Practitioners and Human Rights Advocacy Groups (open access)

Collaboration among Conflict Management Practitioners and Human Rights Advocacy Groups

In a civil war, conflict management practitioners are concerned with bringing the conflict to an end and providing security for civilians. Similarly, human rights advocacy groups are also concerned with minimizing civilian harm. Given the similar intentions of these actors in civil war states, this dissertation explores under what circumstances conflict management practitioners and human rights advocacy groups collaborate. First, I compare to what extent mediation and peacekeeping cases differ with regards to showing signs of interaction; second, I compare how the level of interaction changes depending on whether peacekeeping missions are deployed by the United Nations or regional intergovernmental organizations. I find that human rights groups are more likely to interact with peacekeeping missions, especially when the missions are deployed by the United Nations. Moreover, I analyze to what extent the interaction between human rights groups and peacekeeping operations impacts how human rights groups carry out their advocacy efforts. The findings reveal that the way human rights groups use their advocacy efforts depend on whether the third parties providing peacekeeping operations respond to their requests.
Date: May 2021
Creator: Akyol, Seyma N.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Metal, Pedagogy, Women, Kuwait: An Autoethnographic Feminist Approach to Questioning Systems of Education (open access)

Metal, Pedagogy, Women, Kuwait: An Autoethnographic Feminist Approach to Questioning Systems of Education

This research seeks to explore how the metal arts are taught to women in Kuwait in an undergraduate setting, making the call for the use of feminist pedagogy when teaching the metal arts to women in Kuwait. This research is achieved using the qualitative methodology of analytic autoethnography. The theoretical framework is a feminist lens bridging the social construction of gender with the gendering of objects and feminist standpoint theory. The data comes from the experiences of creating three of my own pieces of artwork as well as the pieces themselves in tandem with historical, political, and cultural contexts. The analysis from this research is then bridged with feminist pedagogy in order to begin to develop an inclusive metal arts curriculum for women in Kuwait.
Date: May 2021
Creator: Alayar, Moneerah
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Saudi Mothers' Experiences Maintaining Their Young Children's Arabic Language and Islamic-Saudi Identity

As more Saudi individuals temporarily settle in the United States to pursue higher education, it becomes increasingly important to understand the impact this experience has on their families. The purpose of this qualitative instrumental case study was to examine Saudi mothers' experiences and motivations after transitioning to life in the United States. The main research question was: What are Saudi mothers' experiences of supporting their children maintaining and developing Arabic language skills and Islamic-Saudi identities while they are learning English and Western culture in U.S. schools? The sub-questions of the study were: Why do Saudi mothers in this study want their children to learn the Arabic language and culture? What are their concerns? What are the challenges Saudi mothers face in socializing their children to develop their Islamic-Saudi identity? What practices do mothers use to help their children preserve their Arabic language and develop the Islamic Saudi-identity while growing up in the United States? This study was conceptually framed within the theories of parenting style and acculturation. Participants in the study were five Saudi mothers pursuing higher education in Texas. Data were collected through three semi-structured interviews and four audio journals with each participant, and a focus group with the …
Date: May 2021
Creator: Albakr, Ashwaq Mohammed
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Radial Solutions of Singular Semilinear Equations on Exterior Domains

We prove the existence and nonexistence of radial solutions of singular semilinear equations Δu + k(x)f(u)=0 with boundary condition on the exterior of the ball with radius R>0 in ℝ^N such that lim r →∞ u(r)=0, where f: ℝ \ {0} →ℝ is an odd and locally Lipschitz continuous nonlinear function such that there exists a β >0 with f <0 on (0, β), f >0 on (β, ∞), and K(r) ~ r^-α for some α >0.
Date: May 2021
Creator: Ali, Mageed Hameed
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

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

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
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
Southwest Retort, Volume 73, Number 9, May 2021 (open access)

Southwest Retort, Volume 73, Number 9, May 2021

This publication of the Dallas-Fort Worth Section of the American Chemical Society includes information about research, prominent scientist, organizational business, and various other stories of interest to the community.
Date: May 2021
Creator: American Chemical Society. Dallas/Fort Worth Section.
Object Type: Journal/Magazine/Newsletter
System: The UNT Digital Library
The Newsletter of the Texas Chapter of the American Fisheries Society, Volume 47, Number 1, May 2021 (open access)

The Newsletter of the Texas Chapter of the American Fisheries Society, Volume 47, Number 1, May 2021

Newsletter of the Texas Chapter of the American Fisheries Society containing information about the organization, membership, and field of aquaculture and ecosystem management.
Date: May 2021
Creator: American Fisheries Society. Texas Chapter.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Discovering Potential for Sense of Community, Social Support, and Wellness Impacts within Interscholastic Sports Officials (open access)

Discovering Potential for Sense of Community, Social Support, and Wellness Impacts within Interscholastic Sports Officials

Data management plan for the grant "Discovering Potential for Sense of Community, Social Support, and Wellness Impacts within Interscholastic Sports Officials." Research seeking to provide an in-depth exploratory look at the behaviors of interscholastic sport officials as they relate to motivation for initial and continued participation, barriers to participation as an interscholastic sport official, and the social, community and health impacts of participation.
Date: 2021-05-01/2021-12-31
Creator: Anderson, Austin
Object Type: Text
System: The UNT Digital Library
Modified Aesthetics on an Inner Space (open access)

Modified Aesthetics on an Inner Space

Brief Artist Statement by Russell Anderson as part of a 2021 MFA Exhibition, entitled "Modified Aesthetics on an Inner Space” in the Cora Stafford Gallery on the campus of the University of North Texas on March 29-April 9, 2021.
Date: May 2021
Creator: Anderson, Russell
Object Type: Text
System: The UNT Digital Library

Doctoral Recital: 2021-05-03 – Lilliana V. Aponte Moreno, mezzo-soprano

Recital presented at the UNT College of Music Voertman Hall in partial fulfillment of the Doctor of Musical Arts (DMA) degree.
Date: May 3, 2021
Creator: Aponte Moreno, Lilliana V.
Object Type: Video
System: The UNT Digital Library
Ultrafast dephasing in hydrogen-bonded pyridine–water mixtures (open access)

Ultrafast dephasing in hydrogen-bonded pyridine–water mixtures

Article studying Hydrogen-bonded pyridine–water mixtures by a time-frequency resolved coherent Raman spectroscopic technique.
Date: May 4, 2021
Creator: Ariunbold, Gombojav O.; Semon, Bryan; Nagpal, Supriya & Rostovtsev, Yuri V.
Object Type: Article
System: The UNT Digital Library

The Ends of Smaller Worlds

The Ends of Smaller Worlds is a collection of short stories set in Indiana. The preface is about the representation of the information age using elements of dirty realism and Gothic fiction.
Date: May 2021
Creator: Armes, Brett
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Thresholds (open access)

Thresholds

Brief Artist Statement by Lara Asam as part of a 2021 MFA Exhibition, entitled "Thresholds” in the Cora Stafford Gallery on the campus of the University of North Texas on April 12-22, 2021.
Date: May 2021
Creator: Asam, Lara
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Elicitation of words for professions transcript

Elicitation of words for professions

Recording of an elicitation of a word list for names of different professions in Mankiyali. English equivalents are used as prompts. Gohar Rehman is a male shop keeper who is 38 years old at the time of recording.
Date: May 16, 2021
Creator: Aurangzeb
Object Type: Sound
System: The UNT Digital Library
Comprehensive comparison of Apple Watch and Fitbit monitors in a free-living setting (open access)

Comprehensive comparison of Apple Watch and Fitbit monitors in a free-living setting

This article evaluates the accuracy of three consumer-based activity monitors, Fitbit Charge 2, Fitbit Alta, and the Apple Watch 2, all worn on the wrist, in estimating step counts, moderate-to-vigorous minutes (MVPA), and heart rate in a free-living setting.
Date: May 26, 2021
Creator: Bai, Yang; Tompkins, Connie; Gell, Nancy; Dione, Dakota; Zhang, Tao & Byun, Wonwoo
Object Type: Article
System: The UNT Digital Library

Investigation of Porous Ceramic Structure by Freeze-Casting

The design and fabrication of porous ceramic materials with anisotropic properties has, in recent years, gained popularity due to their potential application in various areas that include medical, energy, defense, space, and aerospace. Freeze-casting is an effective, low-cost, and safe method as a wet shaping technique to create these structures. To control the morphology of these materials, many critical factors were found to play an important role. In this dissertation, the processing parameters of the magnetic field-assisted freeze-casting method were optimized with a focus on comparing the structure obtained using vertical and horizontal magnetic fields and understanding the mechanisms that occur under different freezing modes. More specifically, this processing method was used to produce Al2O3 and B4C porous ceramics materials with unidirectionally-aligned pore channels. The effect of the vertical and horizontal magnetic field strength and direction, concentration of magnetic material (Fe3O4), cooling rate, and freezing time were examined. The resulting ceramics with highly aligned pore channels were infiltrated with molten metal to create metal matrix composites. The mechanical properties of these structures were measured and were subsequently correlated to their morphology and composition.
Date: May 2021
Creator: Bakkar, Said Adnan
Object Type: Thesis or Dissertation
System: The UNT Digital Library
At the Junction of Dissemination and Implementation: Facilitating Access to Behavior Analytic Research (open access)

At the Junction of Dissemination and Implementation: Facilitating Access to Behavior Analytic Research

Research in scholarly communication is usually limited to the use and dissemination of scientific material by scholars. This excludes the transfer of knowledge from research producers to service providers. Some may argue the primary function of science is to investigate the conditions in the lab so everyday interactions with the environment are more effective and efficient. This is the underlying philosophy of the science of behavior analysis. Comprised of a basic science, an applied science and a philosophy the field of behavior analysis relies on research developments to inform effective practice. Guided by dissemination processes studied in information science, this investigation revealed the content layer in behavior analysis is primarily comprised of journal articles. Ninety four percent of the research artifacts cited in the current content layer are from journal articles. Other dissemination channels used to develop the behavior analytic content layer included scientific magazine articles, oral reports, dissertations and theses, and unpublished manuscripts. The information use environment for professionals in this field is very different than that of the scholars; most professionals do not have access to a university library. Therefore, the research producers are disseminating developments via communication channels some service providers cannot access. This investigation reveals the …
Date: May 2021
Creator: Bank, Nicole L.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Not Just About a Piece of Cloth: Three Content Analysis of an Online Anti-Mandatory Hijab Movement in Iran (open access)

Not Just About a Piece of Cloth: Three Content Analysis of an Online Anti-Mandatory Hijab Movement in Iran

This dissertation investigates the My Stealthy Freedom (MSF) movement, an online movement against mandatory hijab laws in Iran, building on two leading lead social movements' theories, political processes and framing processes theories. Study 1 explores the utility of a tactical approach for explaining the movement's pace of insurgency. I employ a conceptual repertoire focused upon the political process model's core concepts of tactical innovation and tactical adaptations, supplementing these older concepts with the more recently proposed concept of tactical freeze and a newly proposed concept of tactical hashtags that is of particular relevance to online movements. Study 2 focuses on extracting hidden patterns and emotional characteristics in the MSF movement by conducting a topic modeling study on the text appearing in the captions of the main account of the movement on Instagram. It was shown that the actions of Masih Alinejad, the founder of the movement, represented by her online activity and extracted by means of topic modeling, is directly affected by the sequence of important events happening in Iran concluding to a transformation of a social movement to political one. Study 3 models how social movements use social media in the formation of affective publics and apply this model …
Date: May 2021
Creator: Basmechi, Farinaz
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Three Essays on Social Media Use and Information Sharing Behavior

Social media platforms create rich social structures, expand users' boundaries of social networks and revolutionize traditional forms of communications, social interactions and social relationships. These platforms not only facilitate the creation and sharing of news and information, but they also drive various kinds of businesses models, processes and operations, knowledge sharing, marketing strategies for brand management and socio-political discourses essential for healthy and democratic functions. As such, social media has greater implications on organizations and society brought about by individuals' social media usage patterns, and therefore, calls for further investigations. The main objective of this dissertation is to explore and offer insights into such social media usage and information sharing behaviors via data driven examination of various theories. This dissertation involves three studies that focus on factors that explain individuals' three different social media usage behaviors. Essay 1 investigates individuals' perceived importance of online affiliation, self-esteem, self-regulation and risk-benefit structure as antecedents of users' geo-tagging behavior on social media. Essay 2 examines the role of online news quality, source credibility, individuals' perception towards online civic engagement, attitude towards news sharing and social influences to understand users' news sharing behavior on social media platforms. Essay 3 seeks to examine the individuals' …
Date: May 2021
Creator: Bhagat, Sarbottam
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Early Intervention Referral and Service Frequency for Children with Visual Impairments: Experiences from the Field (open access)

Early Intervention Referral and Service Frequency for Children with Visual Impairments: Experiences from the Field

The purpose of this study was to examine differences in early intervention (EI) referral and service frequency for children with blindness or visual impairment (BVI) and gather information about the practices and experiences of vision professionals across the United States. The study focused on obtaining data from certified teachers of students with visual impairment (CTVI) and certified orientation and mobility specialists (COMS) in the United States. Information collected included descriptive statistics and professional information about EI for children with BVI, and information about the referral process and service frequency for children with BVI during EI. Thirty-three states were represented in the collected data. Of these states, 26 had responses from four or more professionals, the criteria for inclusion in the analyses. Participants provided information based on a researcher-developed survey requesting information related to the procedures used to provide EI services for children with BVI. Questions were adapted from established instruments where possible. Across states, there were some statistically significant differences in CTVIs and COMS reports of procedures regarding the role of professional collaboration, parent/caregiver participation in IFSP meetings, strengths/resources utilized by vision professionals, and challenges parents/families encountered when accessing EI services for their child with BVI. No statistically significant differences …
Date: May 2021
Creator: Bishop, Audra Lea
Object Type: Thesis or Dissertation
System: The UNT Digital Library