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- Creators: Arizona State University
- Creators: Poulenc, Francis, 1899-1963
Description
“Mix Mix Tayo: The Many Pieces in Our Stories'' is a written reflection, exploring the creation of the dance documentary, Carried Across the Water as well as the community event, Mix Mix Tayo. The ideas behind these works are centered in storytelling, filipino american identity and community. This research explores the use of film, dance, event production and the mixing of elements to create new wholes in order to communicate these ideas. These works were imagined in response to a call that was felt from people actively searching for healing, community and ancestral knowledge.
ContributorsCurry, Nicole (Author) / Standley, Eileen (Thesis advisor) / Fitzgerald, Mary (Committee member) / Nascimento, Eliciana (Committee member) / Arizona State University (Publisher)
Created2020
Description
Per- and polyfluoroalkyl substances (PFAS) are a group of man-made chemicals that are detected ubiquitously in the aquatic environment, biota, and humans. Human exposure and adverse health of PFAS through consuming impacted drinking water is getting regulatory attention. Adsorption using granular activated carbon (GAC) and ion exchange resin (IX) has proved to be efficient in removing PFAS from water. There is a need to study the effectiveness of commercially available sorbents in PFAS removal at the pilot-scale with real PFAS contaminated water, which would aid in efficient full-scale plant design. Additionally, there is also a need to have validated bench-scale testing techniques to aid municipalities and researchers in selecting or comparing adsorbents to remove PFAS. Rapid Small-Scale Column Tests (RSSCTs) are bench-scale testing to assess media performance and operational life to remove trace organics but have not been validated for PFAS. Different design considerations exist for RSSCTs, which rely upon either proportional diffusivity (PD) or constant diffusivity (CD) dimensionless scaling relationships.
This thesis aims to validate the use of RSSCTs to simulate PFAS breakthrough in pilot columns. First, a pilot-scale study using two GACs and an IX was conducted for five months at a wellsite in central Arizona. PFAS adsorption capacity was greatest for a commercial IX, and then two GAC sources exhibited similar performance. Second, RSSCTs scaled using PD or CD relationships, simulated the pilot columns, were designed and performed. For IX and the two types of GAC, the CD–RSSCTs simulated the PFAS breakthrough concentration, shape, and order of C8 to C4 compounds observed pilot columns better than the PD-RSSCTs. Finally, PFAS breakthrough and adsorption capacities for PD- and CD-RSSCTs were performed on multiple groundwaters (GWs) from across Arizona to assess the treatability of PFAS chain length and functional head-group moieties. PFAS breakthrough in GAC and IX was dictated by chain length (C4>C6>C8) and functional group (PFCAs>PFSAs) of the compound. Shorter-chain PFAS broke through earlier than the longer chain, and removal trends were related to the hydrophobicity of PFAS. Overall, single-use IX performed superior to any of the evaluated GACs across a range of water chemistries in Arizona GWs.
This thesis aims to validate the use of RSSCTs to simulate PFAS breakthrough in pilot columns. First, a pilot-scale study using two GACs and an IX was conducted for five months at a wellsite in central Arizona. PFAS adsorption capacity was greatest for a commercial IX, and then two GAC sources exhibited similar performance. Second, RSSCTs scaled using PD or CD relationships, simulated the pilot columns, were designed and performed. For IX and the two types of GAC, the CD–RSSCTs simulated the PFAS breakthrough concentration, shape, and order of C8 to C4 compounds observed pilot columns better than the PD-RSSCTs. Finally, PFAS breakthrough and adsorption capacities for PD- and CD-RSSCTs were performed on multiple groundwaters (GWs) from across Arizona to assess the treatability of PFAS chain length and functional head-group moieties. PFAS breakthrough in GAC and IX was dictated by chain length (C4>C6>C8) and functional group (PFCAs>PFSAs) of the compound. Shorter-chain PFAS broke through earlier than the longer chain, and removal trends were related to the hydrophobicity of PFAS. Overall, single-use IX performed superior to any of the evaluated GACs across a range of water chemistries in Arizona GWs.
ContributorsVenkatesh, Krishishvar (Author) / Westerhoff, Paul (Thesis advisor) / Sinha, Shahnawaz (Committee member) / Lind, Marylaura (Committee member) / Arizona State University (Publisher)
Created2020
Description
This dissertation investigates how rural e-commerce survives and thrives in resource-scarce rural China in the contemporary era. Building upon literatures on developmental state, state capitalism, industrial policy, and platform economy, this dissertation proposes a new theoretical framework, termed Digital Developmental Village, to understand China’s rural e-commerce development against rural China’s broader socioeconomic and politico-institutional contexts and the evolution of China’s political economy by underscoring three levels of interactions between the central government, local governments, e-commerce platform giants, and rural entrepreneurs.
This dissertation draws upon the data from in-depth interviews with different kinds of participants involved with e-commerce at different places in which e-commerce-related activities occur through multi-site fieldwork across six East China provinces, together with data from secondary data gathering, to scrutinize interactions of four parties at each level. At the national level, this dissertation investigates the coevolution of the Digital Developmental Village model and finds that the bureaucratic evolution and emergence of new economic sector initially created and subsequently developed by private actors will be eventually subjected to the influence of China’s state capitalism. At the local level, in consideration of the factors of local governance approach, the pre-existing robust local economic sectors, and migration patterns, this dissertation creates a typological framework to explore the formation of e-commerce villages in varied settings of the combinations of three factors above. At the individual level, this dissertation finds that rural e-commerce entrepreneurs may achieve economic successes through some more intense forms of embeddedness, which are deemed commercially unwise in the extant literature, within differing local socioeconomic and politico-institutional contexts in China. Lastly, this dissertation analyzes the expansion of the Communist Party of China into rural e-commerce in the business incubator role and sees such organizational expansion as the efforts to implicitly exercise control over rural e-commerce. In sum, through top-down policy directives and bottom-up party organizational expansion, the Chinese state has been gradually transforming rural e-commerce to a new form of state capitalism with potential global impacts, which can empower resource-scarce villages and infuse two kinds of industrial policies to stimulate technological advances.
This dissertation draws upon the data from in-depth interviews with different kinds of participants involved with e-commerce at different places in which e-commerce-related activities occur through multi-site fieldwork across six East China provinces, together with data from secondary data gathering, to scrutinize interactions of four parties at each level. At the national level, this dissertation investigates the coevolution of the Digital Developmental Village model and finds that the bureaucratic evolution and emergence of new economic sector initially created and subsequently developed by private actors will be eventually subjected to the influence of China’s state capitalism. At the local level, in consideration of the factors of local governance approach, the pre-existing robust local economic sectors, and migration patterns, this dissertation creates a typological framework to explore the formation of e-commerce villages in varied settings of the combinations of three factors above. At the individual level, this dissertation finds that rural e-commerce entrepreneurs may achieve economic successes through some more intense forms of embeddedness, which are deemed commercially unwise in the extant literature, within differing local socioeconomic and politico-institutional contexts in China. Lastly, this dissertation analyzes the expansion of the Communist Party of China into rural e-commerce in the business incubator role and sees such organizational expansion as the efforts to implicitly exercise control over rural e-commerce. In sum, through top-down policy directives and bottom-up party organizational expansion, the Chinese state has been gradually transforming rural e-commerce to a new form of state capitalism with potential global impacts, which can empower resource-scarce villages and infuse two kinds of industrial policies to stimulate technological advances.
ContributorsYou, Tianlong (Author) / Romero, Mary (Thesis advisor) / Jurik, Nancy (Committee member) / Zhou, Min (Committee member) / Arizona State University (Publisher)
Created2020
Description
C*-algebras of categories of paths were introduced by Spielberg in 2014 and generalize C*-algebras of higher rank graphs. An approximately finite dimensional (AF) C*-algebra is one which is isomorphic to an inductive limit of finite dimensional C*-algebras. In 2012, D.G. Evans and A. Sims proposed an analogue of a cycle for higher rank graphs and show that the lack of such an object is necessary for the associated C*-algebra to be AF. Here, I give a class of examples of categories of paths whose associated C*-algebras are Morita equivalent to a large number of periodic continued fraction AF algebras, first described by Effros and Shen in 1980. I then provide two examples which show that the analogue of cycles proposed by Evans and Sims is neither a necessary nor a sufficient condition for the C*-algebra of a category of paths to be AF.
ContributorsMitscher, Ian (Author) / Spielberg, John (Thesis advisor) / Bremner, Andrew (Committee member) / Kalizsewski, Steven (Committee member) / Kawski, Matthias (Committee member) / Quigg, John (Committee member) / Arizona State University (Publisher)
Created2020
Description
Nuclear Power Plants (NPP) have complex and dynamic work environments. Nuclear safety and organizational management rely largely on human performance and teamwork. Multi-disciplinary teams work interdependently to complete cognitively demanding tasks such as outage control. The outage control period has the highest risk of core damage and radiation exposure. Thus, team coordination and communication are critically important during this period. The purpose of this thesis is to review and synthesize teamwork studies in NPPs, outage management studies, official Licensee Event Reports (LER), and Inspection Reports (IRs) to characterize team brittleness in NPP systems. Focusing on team brittleness can provide critical insights about how to increase NPP robustness and to create a resilient NPP system. For this reason, more than 900 official LERs and IRs reports were analyzed to understand human and team errors in the United States (US) nuclear power plants. The findings were evaluated by subject matter experts to create a better understanding of team cognition in US nuclear power plants. The results of analysis indicated that human errors could be caused by individual human errors, team errors, procedural errors, design errors, or organizational errors. In addition to these, some of the findings showed that number of reactors, operation year and operation mode could affect the number of reported incidents.
ContributorsAKCA, SALLY SALIHA (Author) / Cooke, Nancy (Thesis advisor) / Niemczyk, Mary (Committee member) / Branaghan, Russell (Committee member) / Arizona State University (Publisher)
Created2020
Description
Complex dynamical systems are the kind of systems with many interacting components that usually have nonlinear dynamics. Those systems exist in a wide range of disciplines, such as physical, biological, and social fields. Those systems, due to a large amount of interacting components, tend to possess very high dimensionality. Additionally, due to the intrinsic nonlinear dynamics, they have tremendous rich system behavior, such as bifurcation, synchronization, chaos, solitons. To develop methods to predict and control those systems has always been a challenge and an active research area.
My research mainly concentrates on predicting and controlling tipping points (saddle-node bifurcation) in complex ecological systems, comparing linear and nonlinear control methods in complex dynamical systems. Moreover, I use advanced artificial neural networks to predict chaotic spatiotemporal dynamical systems. Complex networked systems can exhibit a tipping point (a “point of no return”) at which a total collapse occurs. Using complex mutualistic networks in ecology as a prototype class of systems, I carry out a dimension reduction process to arrive at an effective two-dimensional (2D) system with the two dynamical variables corresponding to the average pollinator and plant abundances, respectively. I demonstrate that, using 59 empirical mutualistic networks extracted from real data, our 2D model can accurately predict the occurrence of a tipping point even in the presence of stochastic disturbances. I also develop an ecologically feasible strategy to manage/control the tipping point by maintaining the abundance of a particular pollinator species at a constant level, which essentially removes the hysteresis associated with tipping points.
Besides, I also find that the nodal importance ranking for nonlinear and linear control exhibits opposite trends: for the former, large degree nodes are more important but for the latter, the importance scale is tilted towards the small-degree nodes, suggesting strongly irrelevance of linear controllability to these systems. Focusing on a class of recurrent neural networks - reservoir computing systems that have recently been exploited for model-free prediction of nonlinear dynamical systems, I uncover a surprising phenomenon: the emergence of an interval in the spectral radius of the neural network in which the prediction error is minimized.
My research mainly concentrates on predicting and controlling tipping points (saddle-node bifurcation) in complex ecological systems, comparing linear and nonlinear control methods in complex dynamical systems. Moreover, I use advanced artificial neural networks to predict chaotic spatiotemporal dynamical systems. Complex networked systems can exhibit a tipping point (a “point of no return”) at which a total collapse occurs. Using complex mutualistic networks in ecology as a prototype class of systems, I carry out a dimension reduction process to arrive at an effective two-dimensional (2D) system with the two dynamical variables corresponding to the average pollinator and plant abundances, respectively. I demonstrate that, using 59 empirical mutualistic networks extracted from real data, our 2D model can accurately predict the occurrence of a tipping point even in the presence of stochastic disturbances. I also develop an ecologically feasible strategy to manage/control the tipping point by maintaining the abundance of a particular pollinator species at a constant level, which essentially removes the hysteresis associated with tipping points.
Besides, I also find that the nodal importance ranking for nonlinear and linear control exhibits opposite trends: for the former, large degree nodes are more important but for the latter, the importance scale is tilted towards the small-degree nodes, suggesting strongly irrelevance of linear controllability to these systems. Focusing on a class of recurrent neural networks - reservoir computing systems that have recently been exploited for model-free prediction of nonlinear dynamical systems, I uncover a surprising phenomenon: the emergence of an interval in the spectral radius of the neural network in which the prediction error is minimized.
ContributorsJiang, Junjie (Author) / Lai, Ying-Cheng (Thesis advisor) / Papandreou-Suppappola, Antonia (Committee member) / Wang, Xiao (Committee member) / Zhang, Yanchao (Committee member) / Arizona State University (Publisher)
Created2020
Description
As the global community raises concerns regarding the ever-increasing urgency of climate change, efforts to explore innovative strategies in the fight against this anthropogenic threat is growing. Along with other greenhouse gas mitigation technologies, Direct Air Capture (DAC) or the technology of removing carbon dioxide directly from the air has received considerable attention. As an emerging technology, the cost of DAC has been the prime focus not only in scientific society but also between entrepreneurs and policymakers. While skeptics are concerned about the high cost and impact of DAC implementation at scales comparable to the magnitude of climate change, industrial practitioners have demonstrated a pragmatic path to cost reduction. Based on the latest advancements in the field, this dissertation investigates the economic feasibility of DAC and its role in future energy systems. With a focus on the economics of carbon capture, this work compares DAC with other carbon capture technologies from a systemic perspective. Moreover, DAC’s major expenses are investigated to highlight critical improvements necessary for commercialization. In this dissertation, DAC is treated as a backstop mitigation technology that can address carbon dioxide emissions regardless of the source of emission. DAC determines the price of carbon dioxide removal when other mitigation technologies fall short in meeting their goals. The results indicate that DAC, even at its current price, is a reliable backup and is competitive with more mature technologies such as post-combustion capture. To reduce the cost, the most crucial component of a DAC design, i.e., the sorbent material, must be the centerpiece of innovation. In conclusion, DAC demonstrates the potential for not only negative emissions (carbon dioxide removal with the purpose of addressing past emissions), but also for addressing today’s emissions. The results emphasize that by choosing an effective scale-up strategy, DAC can become sufficiently cheap to play a crucial role in decarbonizing the energy system in the near future. Compared to other large-scale decarbonization strategies, DAC can achieve this goal with the least impact on our existing energy infrastructure.
ContributorsAzarabadi, Habib (Author) / Lackner, Klaus S (Thesis advisor) / Allenby, Braden R. (Committee member) / Dirks, Gary W (Committee member) / Reddy, Agami (Committee member) / Arizona State University (Publisher)
Created2020
Description
Recent extreme weather events such the 2020 Nashville, Tennessee tornado and Hurricane Maria highlight the devastating economic losses and loss of life associated with weather-related disasters. Understanding the impacts of extreme weather events is critical to mitigating disaster losses and increasing societal resilience to future events. Geographical approaches are best suited to examine social and ecological factors in extreme weather event impacts because they systematically examine the spatial interactions (e.g., flows, processes, impacts) of the earth’s system and human-environment relationships. The goal of this research is to demonstrate the utility of geographical approaches in assessing social and ecological factors in extreme weather event impacts. The first two papers analyze the social factors in the impact of Hurricane Sandy through the application of social geographical factors. The first paper examines how knowledge disconnect between experts (climatologists, urban planners, civil engineers) and policy-makers contributed to the damaging impacts of Hurricane Sandy. The second paper examines the role of land use suitability as suggested by Ian McHarg in 1969 and unsustainable planning in the impact of Hurricane Sandy. Overlay analyses of storm surge and damage buildings show damage losses would have been significantly reduced had development followed McHarg’s suggested land use suitability. The last two papers examine the utility of Unpiloted Aerial Systems (UASs) technologies and geospatial methods (ecological geographical approaches) in tornado damage surveys. The third paper discusses the benefits, limitations, and procedures of using UASs technologies in tornado damage surveys. The fourth paper examines topographical influences on tornadoes using UAS technologies and geospatial methods (ecological geographical approach). This paper highlights how topography can play a major role in tornado behavior (damage intensity and path deviation) and demonstrates how UASs technologies can be invaluable tools in damage assessments and improving the understanding of severe storm dynamics (e.g., tornadic wind interactions with topography). Overall, the significance of these four papers demonstrates the potential to improve societal resilience to future extreme weather events and mitigate future losses by better understanding the social and ecological components in extreme weather event impacts through geographical approaches.
ContributorsWagner, Melissa Anne (Author) / Cerveny, Randall S. (Thesis advisor) / Wentz, Elizabeth (Thesis advisor) / Chhetri, Netra B (Committee member) / Vivoni, Enrique R (Committee member) / Arizona State University (Publisher)
Created2020
Description
For more than 30 years, social science researchers have studied how students in online learning environments interact with each other. This has led to the development of a construct called social presence. Studies have shown that high social presence can lead to improved student retention, engagement, and satisfaction. The literature explores how social presence has been measured by faculty or researchers, but lacks insight on how other university staff can affect social presence in online graduate students. This is an action research mixed-methods study conducted by an academic advisor and attempts to measure social presence through a webpage intervention for an online graduate business program. A pre-and-posttest were conducted in a five month span, as well as semi-structured interviews with students of the program. Results suggest that overall, the intervention did not increase social presence in the program. It also suggests that social presence is developed between students in a variety of ways, and can even be developed between their academic advisor and themselves. Overall, this study acknowledges how academic advisors can explore social presence to improve academic advising techniques and interventions for their programs, while also adding to the literature a different perspective through the eyes of a university staff member.
ContributorsDelgado, Gina Michelle (Author) / Chen, Ying-Chih (Thesis advisor) / Beardsley, Audrey (Committee member) / Tu, Chih-Hsiung (Committee member) / Arizona State University (Publisher)
Created2020
Description
This study examined relations between White parents’ color-blind and implicit racial attitudes and their children’s racial bias as well as moderation by diversity in children’s friends and caregivers, parental warmth, child age, and child sex. The sample included 190 White/Non-Hispanic children (46% female) between the ages of 5 and 9 years (M = 7.11 years, SD = .94) and their mothers (N = 184) and fathers (N = 154). Data used were parents’ reports of color-blind racial attitudes (Color-blind Racial Attitudes Scale; CoBRAS), parental warmth, and racial/ethnic diversity of children’s friendships and caregivers, direct assessment of primary parent implicit racial attitudes (Implicit Association Test; IAT), and direct assessment of children’s racial attitudes. Results supported hypothesized relations between parent racial attitudes and some child racial bias variables, especially under certain conditions. Specifically, both mothers’ and fathers’ color-blind racial attitudes were positively related to children’s social inclusion preference for White children over Black children and parents’ implicit White preference positively predicted child social inclusion racial bias, but only for younger children. Fathers’ color-blind racial attitudes positively predicted children’s social inclusion racial bias only when children’s pre-K caregivers were mostly White and were inversely related to children’s implicit White preference when children’s caregivers were more racially heterogeneous. Finally, parental warmth moderated relations such that, when mothers’ warmth was low, mother color-blind attitudes were negatively related to children’s racial bias in social distance preference and fathers’ color-blind attitudes positively predicted children’s social inclusion bias only when father warmth was low or average.
ContributorsGal-Szabo, Diana Elena (Author) / Spinrad, Tracy L (Thesis advisor) / Eisenberg, Nancy (Committee member) / Spanierman, Lisa B (Committee member) / Bradley, Robert (Committee member) / Arizona State University (Publisher)
Created2020