ASU Electronic Theses and Dissertations
This collection includes most of the ASU Theses and Dissertations from 2011 to present. ASU Theses and Dissertations are available in downloadable PDF format; however, a small percentage of items are under embargo. Information about the dissertations/theses includes degree information, committee members, an abstract, supporting data or media.
In addition to the electronic theses found in the ASU Digital Repository, ASU Theses and Dissertations can be found in the ASU Library Catalog.
Dissertations and Theses granted by Arizona State University are archived and made available through a joint effort of the ASU Graduate College and the ASU Libraries. For more information or questions about this collection contact or visit the Digital Repository ETD Library Guide or contact the ASU Graduate College at gradformat@asu.edu.
Displaying 91 - 97 of 97
Filtering by
- Creators: Mobasher, Barzin
Description
The purpose of this study was to understand Black students within the Class of 2023 at Cleveland Heights High School (CHHS) motivation for pursuing a post-secondary education through the lens of Critical Race Theory (CRT), Community Cultural Wealth (CCW) and Counter-storytelling. CHHS is identified as a comprehensive high school where students have access to a rigorous, engaging curriculum that will prepare them for college and career. CHHS is located on the East side of Cleveland and has a predominately Black student population. Despite the district and CHHS efforts to cultivate a college going culture, the college enrollment rate is around 46 percent. This study utilized a qualitative Critical Race Methodology (CRM) as a guiding framework in order to negate the deficit thinking stereotype that U.S society has unjustly placed on Black students in their pursuit of higher education. CRM in education challenges biological and cultural deficit stories through counter-storytelling, oral traditions, historiographies, etc., (Solórzano & Yosso, 2002, p.37). Utilizing this framework allowed Black students to see their life experiences as a source of value and a beneficial asset. By understanding students’ motivations for pursuing a postsecondary education will in turn help build systems of support as they prepare to tackle perceived post-secondary barriers. Study participants are a part of the Gaining Early Awareness and Readiness for Undergraduate Program (GEAR UP). The students that participated in the study met the following criteria: participate in Gear Up, Black male or female, and first or second-generation college student. This study utilized an action research framework. In order to gain a better understanding of how college and career readiness workshops impacts students understanding and motivations to pursue a postsecondary education; students participated in a five-week long college and career readiness summer program. Students created personal narratives through the lens of counter-narrative storytelling. Counter-narratives are important means to document and share how race influences the educational experiences of people of color (Miller et al., 2020, p.273). The findings were analyzed using verbatim participant responses and four major themes emerged. The implications of this findings and recommendations for future research are provided in the final chapter.
ContributorsDaniel, Carmen C (Author) / Fischman, Gustavo (Thesis advisor) / Graves-Wolf, Leigh (Committee member) / Tefera, Adai (Committee member) / Arizona State University (Publisher)
Created2021
Description
Layer-wise extrusion of soft-solid like cement pastes and mortars is commonly used in 3D printing of concrete. Rheological and mechanical characterization of the printable binder for on-demand flow and subsequent structuration is a critical challenge. This research is an effort to understand the mechanics of cementitious binders as soft solids in the fresh state, towards establishing material-process relationships to enhance print quality. This study introduces 3D printable binders developed based on rotational and capillary rheology test parameters, and establish the direct influence of packing coefficients, geometric ratio, slip velocities, and critical print velocities on the extrudate quality. The ratio of packing fraction to the square of average particle diameter (0.01-0.02), and equivalent microstructural index (5-20) were suitable for printing, and were directly related to the cohesion and extrusional yield stress of the material. In fact, steady state pressure for printing (30-40 kPa) is proportional to the extrusional yield stress, and increases with the geometric ratio (0-60) and print velocity (5-50 mm/s). Higher print velocities results in higher wall shear stresses and was exponentially related to the slip layer thickness (estimated between 1-5μ), while the addition of superplasticizers improve the slip layer thickness and the extrudate flow. However, the steady state pressure and printer capacity limits the maximum print velocity while the deadzone length limits the minimum velocity allowable (critical velocity regime) for printing. The evolution of buildability with time for the fresh state mortars was characterized with digital image correlation using compressive strain and strain rate in printed layers. The fresh state characteristics (interlayer and interfilamentous) and process parameters (layer height and fiber dimensions) influence the hardened mechanical properties. A lower layer height generally improves the mechanical properties and slight addition of fiber (up to 0.3% by volume) results in a 15-30% increase in the mechanical properties. 3D scanning and point-cloud analysis was also used to assess the geometric tolerance of a print based on mean error distances, print accuracy index, and layer-wise percent overlap. The research output will contribute to a synergistic material-process design and development of test methods for printability in the context of 3D printing of concrete.
ContributorsAmbadi Omanakuttan Nair, Sooraj Kumar (Author) / Neithalath, Narayanan (Thesis advisor) / Rajan, Subramaniam (Committee member) / Mobasher, Barzin (Committee member) / Hoover, Christian (Committee member) / Chawla, Nikhilesh (Committee member) / Arizona State University (Publisher)
Created2021
Description
Composite materials have gained interest in the aerospace, mechanical and civil engineering industries due to their desirable properties - high specific strength and modulus, and superior resistance to fatigue. Design engineers greatly benefit from a reliable predictive tool that can calculate the deformations, strains, and stresses of composites under uniaxial and multiaxial states of loading including damage and failure predictions. Obtaining this information from (laboratory) experimental testing is costly, time consuming, and sometimes, impractical. On the other hand, numerical modeling of composite materials provides a tool (virtual testing) that can be used as a supplemental and an alternate procedure to obtain data that either cannot be readily obtained via experiments or is not possible with the currently available experimental setup. In this study, a unidirectional composite (Toray T800-F3900) is modeled at the constituent level using repeated unit cells (RUC) so as to obtain homogenized response all the way from the unloaded state up until failure (defined as complete loss of load carrying capacity). The RUC-based model is first calibrated and validated against the principal material direction laboratory tests involving unidirectional loading states. Subsequently, the models are subjected to multi-directional states of loading to generate a point cloud failure data under in-plane and out-of-plane biaxial loading conditions. Failure surfaces thus generated are plotted and compared against analytical failure theories. Results indicate that the developed process and framework can be used to generate a reliable failure prediction procedure that can possibly be used for a variety of composite systems.
ContributorsKatusele, Daniel Mutahwa (Author) / Rajan, Subramaniam (Thesis advisor) / Mobasher, Barzin (Committee member) / Neithalath, Narayanan (Committee member) / Arizona State University (Publisher)
Created2021
Description
Alkali-activated aluminosilicates, commonly known as "geopolymers", are being increasingly studied as a potential replacement for Portland cement. These binders use an alkaline activator, typically alkali silicates, alkali hydroxides or a combination of both along with a silica-and-alumina rich material, such as fly ash or slag, to form a final product with properties comparable to or better than those of ordinary Portland cement. The kinetics of alkali activation is highly dependent on the chemical composition of the binder material and the activator concentration. The influence of binder composition (slag, fly ash or both), different levels of alkalinity, expressed using the ratios of Na2O-to-binders (n) and activator SiO2-to-Na2O ratios (Ms), on the early age behavior in sodium silicate solution (waterglass) activated fly ash-slag blended systems is discussed in this thesis. Optimal binder composition and the n values are selected based on the setting times. Higher activator alkalinity (n value) is required when the amount of slag in the fly ash-slag blended mixtures is reduced. Isothermal calorimetry is performed to evaluate the early age hydration process and to understand the reaction kinetics of the alkali activated systems. The differences in the calorimetric signatures between waterglass activated slag and fly ash-slag blends facilitate an understanding of the impact of the binder composition on the reaction rates. Kinetic modeling is used to quantify the differences in reaction kinetics using the Exponential as well as the Knudsen method. The influence of temperature on the reaction kinetics of activated slag and fly ash-slag blends based on the hydration parameters are discussed. Very high compressive strengths can be obtained both at early ages as well as later ages (more than 70 MPa) with waterglass activated slag mortars. Compressive strength decreases with the increase in the fly ash content. A qualitative evidence of leaching is presented through the electrical conductivity changes in the saturating solution. The impact of leaching and the strength loss is found to be generally higher for the mixtures made using a higher activator Ms and a higher n value. Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy (ATR-FTIR) is used to obtain information about the reaction products.
ContributorsChithiraputhiran, Sundara Raman (Author) / Neithalath, Narayanan (Thesis advisor) / Rajan, Subramaniyam D (Committee member) / Mobasher, Barzin (Committee member) / Arizona State University (Publisher)
Created2012
Description
This dissertation research explores the complexity of transformations of academic lives and academic identities along the multiple, non-linear, conflicting, and paradoxical trajectories of the pre-Soviet, Soviet, and post-Soviet times and spaces. Academic literature on the post-Soviet transformations of higher education has usually focused on structural reforms and policy changes, as well as their compatibility with the European and Western higher education policy agenda. Guided by the theoretical insights from the decolonial and post-Socialist transformation studies, this dissertation research intends to decenter the education policies and reforms from being a focal point of analysis; instead, it spotlights the transformation of Georgian academics through their memories, lived experiences, and imaginations about the future. The study offers insights into personal and collective experiences of being and becoming an academic in the process of navigating the evolving historical, political, cultural, and institutional contexts at three public universities in Georgia. Drawing on the narrative-ethnographic methodology, this study explores the complicated scenes and nuances of Georgian academic space by portraying how academics construct, reconstruct, adjust, resist, negotiate, and reinvent their academic selves during the post-Soviet transformations. Diffractive analysis of the narratives and ethnographic observations illustrates multiple intra-actions of academic identities through various temporal and spatial reconfigurations, revealing that the Soviet past is not left behind, and the European future is not that certain. Instead, the liminal academic space is haunted by the (re)awakened pasts and (re)imagined futures, and their inseparability enacts various co-existing scenarios of defuturing and refuturing of academic identities.
ContributorsTsotniashvili, Keti (Author) / Silova, Iveta (Thesis advisor) / Hailu, Meseret (Committee member) / Oleksiyenko, Anatoly (Committee member) / Fischman, Gustavo (Committee member) / Arizona State University (Publisher)
Created2023
Description
This qualitative study examined how the scientific journal PLOS ONE assembled its editorial board, which is made up of more than 10,000 academic editors based in 131 countries. The study investigated how the board’s geographic diversity is enacted by the human and nonhuman actors of the assemblage. PLOS ONE is an open-access (OA) mega-journal launched in 2006 by the nonprofit organization Public Library of Science (PLOS). It publishes over 16,000 papers yearly, covering more than 200 scientific subjects of science and medicine. I drew on Actor-Network Theory (ANT), which proposes that processes, ideas, organizations, or objects are continuously generated within a network of relationships between human and nonhuman actors. I used the case study methodology and employed two qualitative research methods. First, I conducted semi-structured interviews with 26 academic editors from different fields, including biology and life sciences, chemistry, medicine and health sciences, physics, and social sciences. These editors are affiliated with research institutions across 14 countries. Additionally, I interviewed PLOS leaders, staff members, and a representative from an external contractor. Second, I employed documentary analysis of organizational documents and online secondary data. Findings showed that the human and nonhuman actors of the PLOS ONE editorial board reproduce biases in science based on authors’ and editors’ geographic origin, the journal’s size and the low diversity of PLOS staff members. I also identified that APCs (Article Processing Charges) act as mediators that trigger betrayals among the actors, which has consequences on the stability of the assemblage, especially in terms of trust between the publisher and the scientific community. Finally, this study also identified that publishing an OA mega-journal has contradictions and unexpected effects on the publishing landscape due to its large scale.
ContributorsLujano Vilchis, Ivonne (Author) / Fischman, Gustavo (Thesis advisor) / Kim, Jeongeun (Committee member) / Hailu, Meseret (Committee member) / Dussel, Inés (Committee member) / Arizona State University (Publisher)
Created2023
Description
Students’ learning experience in studio are an essential part in studio-based learning mode and design education. Studio-based learning is defined as an active pedagogy in which the student learns multimodal by solving cases or problems. Students work with personal assignments or group assignments that are critiqued on the basis of formal and informal presentations. Studio-based Learning (SBL) is unlike other learning modes, not only because the pedagogy is different but also because of its distinctive learning spaces. SBL is carried out in the studio, a type of classroom within the university that supports this pedagogy. The studio is more like a combination of classroom and study room, students take courses in studio and are encouraged to finish their design project in the studio during their off-school hours.
Nowadays, the development of undergraduate design education and practice varies significantly among countries as a result of the varying curriculum and pedagogical evolution. For instance, Chinese education in interior design has only thirty years of development while the United States has over one hundred years of experience in the field. Even though both educational goals expect students to be able to manage developing design concepts and design projects, the differences between the two are numerous. This thesis studies a comparative analysis between the two systems and aims to identify students’ real needs and their perception of studio-based learning at Nankai University in China and Arizona State University in the United States as a means to recognize possibilities to improve students’ learning experience. The study includes students, their studio spaces, and their interior design undergraduate programs in both universities. The study utilizes qualitative methods including questionnaires, semi-structured interviews, and observations. The study also includes an analysis of both undergraduate interior design programs in these two universities as case studies. The findings are analyzed and translated into physical and pedagogical recommendations. The findings should be of value for students and faculty in interior design programs in both countries.
Nowadays, the development of undergraduate design education and practice varies significantly among countries as a result of the varying curriculum and pedagogical evolution. For instance, Chinese education in interior design has only thirty years of development while the United States has over one hundred years of experience in the field. Even though both educational goals expect students to be able to manage developing design concepts and design projects, the differences between the two are numerous. This thesis studies a comparative analysis between the two systems and aims to identify students’ real needs and their perception of studio-based learning at Nankai University in China and Arizona State University in the United States as a means to recognize possibilities to improve students’ learning experience. The study includes students, their studio spaces, and their interior design undergraduate programs in both universities. The study utilizes qualitative methods including questionnaires, semi-structured interviews, and observations. The study also includes an analysis of both undergraduate interior design programs in these two universities as case studies. The findings are analyzed and translated into physical and pedagogical recommendations. The findings should be of value for students and faculty in interior design programs in both countries.
ContributorsLiu, Chaofan (Author) / Zingoni, Milagros (Thesis advisor) / Fischman, Gustavo (Committee member) / Brunner, Lori (Committee member) / Arizona State University (Publisher)
Created2020