Matching Items (177)
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Collective human attitudes influenced by macro-forces that impact environmental issues are partially correlated to our behaviors for the good and the harm of the planet. In this thesis, I will explore how collective human attitudes contribute to pro-environmental behaviors, common and pre-existing frames of mind on major conservation dilemmas, and

Collective human attitudes influenced by macro-forces that impact environmental issues are partially correlated to our behaviors for the good and the harm of the planet. In this thesis, I will explore how collective human attitudes contribute to pro-environmental behaviors, common and pre-existing frames of mind on major conservation dilemmas, and finally suggest future directions on how humans could be inclined to take on more environmental responsibility through an increase in human-environmental connectivity. It is found that humans are largely driven by institution structures, education, and social influence. In conclusion, more efforts should be placed to further analyze these structural incentives for pro-environmental behaviors and use them to make environmental stewardship more accessible for all people and diverse circumstances. This can be done by evaluating the human dimensions of what influences human attitudes and behaviors, how to use these forces to systematically influence pro-environmental choices, applying these structural forces to main conservation issues, and further incorporating moral discourse into the environmental research in order to appeal correctly to all aspects and perspectives. Only when human connectivity is understood in relation to the natural sciences will we be able to make positive change in the direction of a healthier Earth.

ContributorsCheek, Alana C (Author) / Vargas, Perla (Thesis director) / Keahey, Jennifer (Committee member) / School of Humanities, Arts, and Cultural Studies (Contributor) / School of Mathematical and Natural Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description

This qualitative project was done as a way to learn more about the personal experiences of Asian American participants surrounding education and how it has impacted their identities, and questions how and if the model minority stereotype has impacted the Asian American student particiapnts. 14 participants were interviewed one-on-one to

This qualitative project was done as a way to learn more about the personal experiences of Asian American participants surrounding education and how it has impacted their identities, and questions how and if the model minority stereotype has impacted the Asian American student particiapnts. 14 participants were interviewed one-on-one to see if there were any patterns in values that their parents had pushed, and revealed that cultural expectations influence the participants’s educational choices, leading to self-regulation in regards to education. Because the shared trait of these participants are being current Asian American students in university at the time of their interviews, experiences range with how acculturated their parents are, the ethnic background of their families, and prior expectations with education.

ContributorsFrancke, Katrielle Ely (Author) / Cayetano, Catalina (Thesis director) / Taylor, Jameien (Committee member) / Department of English (Contributor) / School of Humanities, Arts, and Cultural Studies (Contributor) / School of Music, Dance and Theatre (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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This thesis focuses on the theoretical work done to determine thermodynamic properties of a chalcopyrite thin-film material for use as a photovoltaic material in a tandem device. The material of main focus here is ZnGeAs2, which was chosen for the relative abundance of constituents, favorable photovoltaic properties, and good lattice

This thesis focuses on the theoretical work done to determine thermodynamic properties of a chalcopyrite thin-film material for use as a photovoltaic material in a tandem device. The material of main focus here is ZnGeAs2, which was chosen for the relative abundance of constituents, favorable photovoltaic properties, and good lattice matching with ZnSnP2, the other component in this tandem device. This work is divided into two main chapters, which will cover: calculations and method to determine the formation energy and abundance of native point defects, and a model to calculate the vapor pressure over a ternary material from first-principles. The purpose of this work is to guide experimental work being done in tandem to synthesize ZnGeAs2 in thin-film form with high enough quality such that it can be used as a photovoltaic. Since properties of photovoltaic depend greatly on defect concentrations and film quality, a theoretical understanding of how laboratory conditions affect these properties is very valuable. The work done here is from first-principles and utilizes density functional theory using the local density approximation. Results from the native point defect study show that the zinc vacancy (VZn) and the germanium antisite (GeZn) are the more prominent defects; which most likely produce non-stoichiometric films. The vapor pressure model for a ternary system is validated using known vapor pressure for monatomic and binary test systems. With a valid ternary system vapor pressure model, results show there is a kinetic barrier to decomposition for ZnGeAs2.
ContributorsTucker, Jon R (Author) / Van Schilfgaarde, Mark (Thesis advisor) / Newman, Nathan (Committee member) / Adams, James (Committee member) / Arizona State University (Publisher)
Created2011
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Electromigration in metal interconnects is the most pernicious failure mechanism in semiconductor integrated circuits (ICs). Early electromigration investigations were primarily focused on aluminum interconnects for silicon-based ICs. An alternative metallization compatible with gallium arsenide (GaAs) was required in the development of high-powered radio frequency (RF) compound semiconductor devices operating at

Electromigration in metal interconnects is the most pernicious failure mechanism in semiconductor integrated circuits (ICs). Early electromigration investigations were primarily focused on aluminum interconnects for silicon-based ICs. An alternative metallization compatible with gallium arsenide (GaAs) was required in the development of high-powered radio frequency (RF) compound semiconductor devices operating at higher current densities and elevated temperatures. Gold-based metallization was implemented on GaAs devices because it uniquely forms a very low resistance ohmic contact and gold interconnects have superior electrical and thermal conductivity properties. Gold (Au) was also believed to have improved resistance to electromigration due to its higher melting temperature, yet electromigration reliability data on passivated Au interconnects is scarce and inadequate in the literature. Therefore, the objective of this research was to characterize the electromigration lifetimes of passivated Au interconnects under precisely controlled stress conditions with statistically relevant quantities to obtain accurate model parameters essential for extrapolation to normal operational conditions. This research objective was accomplished through measurement of electromigration lifetimes of large quantities of passivated electroplated Au interconnects utilizing high-resolution in-situ resistance monitoring equipment. Application of moderate accelerated stress conditions with a current density limited to 2 MA/cm2 and oven temperatures in the range of 300°C to 375°C avoided electrical overstress and severe Joule-heated temperature gradients. Temperature coefficients of resistance (TCRs) were measured to determine accurate Joule-heated Au interconnect film temperatures. A failure criterion of 50% resistance degradation was selected to prevent thermal runaway and catastrophic metal ruptures that are problematic of open circuit failure tests. Test structure design was optimized to reduce resistance variation and facilitate failure analysis. Characterization of the Au microstructure yielded a median grain size of 0.91 ìm. All Au lifetime distributions followed log-normal distributions and Black's model was found to be applicable. An activation energy of 0.80 ± 0.05 eV was measured from constant current electromigration tests at multiple temperatures. A current density exponent of 1.91 was extracted from multiple current densities at a constant temperature. Electromigration-induced void morphology along with these model parameters indicated grain boundary diffusion is dominant and the void nucleation mechanism controlled the failure time.
ContributorsKilgore, Stephen (Author) / Adams, James (Thesis advisor) / Schroder, Dieter (Thesis advisor) / Krause, Stephen (Committee member) / Gaw, Craig (Committee member) / Arizona State University (Publisher)
Created2013
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This thesis is a qualitative research study that focuses on siblings of children with Autistic Spectrum Disorder (ASD). Even though it is expected that having a child with ASD in the family will influence the whole family including siblings of the child with ASD, the sibling population is rarely included

This thesis is a qualitative research study that focuses on siblings of children with Autistic Spectrum Disorder (ASD). Even though it is expected that having a child with ASD in the family will influence the whole family including siblings of the child with ASD, the sibling population is rarely included in research related to children with ASD, and there is only limited services available for them. This exploratory study (n=6) is aimed at better understanding the siblings' lives in their family settings in order to identify the siblings' unmet needs and determine how they have been influenced by the child with ASD. This study is also aimed at identifying the most appropriate support for the siblings to help them cope better. The study followed the Resiliency Model of Family Stress, Adjustment, and Adaptation and a narrative theory approach. An in-depth interview with the parents was conducted for the study, so the findings reflect the parents' perception of the siblings. All the themes emerged into two categories: life in the family setting and supports. The findings indicate that the families are striving for balance between the siblings and the children with ASD, but still tend to focus more on the children with ASD. Also, the families tend to have autonomous personal support systems. The parents tend to perceive that these personal support systems are good enough for the siblings; therefore, the parents do not feel that formal support for the siblings was necessary. As a result of the findings, recommendations are made for the organizations that work with individuals with ASD to provide more appropriate services for the families of children with ASD, including siblings. Also, recommendations are made for future studies to clarify more factors related to the siblings due to the limitation of this study; the siblings' lives were reflected vicariously via the parents.
ContributorsJeong, Seong Hae (Author) / Marsiglia, Flavio F (Thesis advisor) / Ayers, Stephanie (Committee member) / Adams, James (Committee member) / Arizona State University (Publisher)
Created2013
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This report will review the mechanical and microstructural properties of the refractory element rhenium (Re) deposited using Laser Additive Manufacturing (LAM). With useable structural strength over 2200 °C, existing applications up to 2760 °C, very high strength, ductility and chemical resistance, interest in Re is understandable. This study includes data

This report will review the mechanical and microstructural properties of the refractory element rhenium (Re) deposited using Laser Additive Manufacturing (LAM). With useable structural strength over 2200 °C, existing applications up to 2760 °C, very high strength, ductility and chemical resistance, interest in Re is understandable. This study includes data about tensile properties including tensile data up to 1925 °C, fracture modes, fatigue and microstructure including deformation systems and potential applications of that information. The bulk mechanical test data will be correlated with nanoindentation and crystallographic examination. LAM properties are compared to the existing properties found in the literature for other manufacturing processes. The literature indicates that Re has three significant slip systems but also twins as part of its deformation mechanisms. While it follows the hcp metal characteristics for deformation, it has interesting and valuable extremes such as high work hardening, potentially high strength, excellent wear resistance and superior elevated temperature strength. These characteristics are discussed in detail.
ContributorsAdams, Robbie (Author) / Chawla, Nikhilesh (Thesis advisor) / Adams, James (Committee member) / Krause, Stephen (Committee member) / Arizona State University (Publisher)
Created2012
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In 2022, integrated circuit interconnects will approach 10 nm and the diffusion barrier layers needed to ensure long lasting devices will be at 1 nm. This dimension means the interconnect will be dominated by the interface and it has been shown the interface is currently eroding device performance. The standard

In 2022, integrated circuit interconnects will approach 10 nm and the diffusion barrier layers needed to ensure long lasting devices will be at 1 nm. This dimension means the interconnect will be dominated by the interface and it has been shown the interface is currently eroding device performance. The standard interconnect system has three layers - a Copper metal core, a Tantalum Adhesion layer and a Tantalum Nitride Diffusion Barrier Layer. An alternate interconnect schema is a Tantalum Nitride barrier layer and Silver as a metal. The adhesion layer is removed from the system along with changing to an alternate, low resistivity metal. First principles are used to assess the interface of the Silver and Tantalum Nitride. Several stoichiometric 1:1 Tantalum Nitride polymorphs are assessed and it is found that the Fe2P crystal structure is actually the most stable crystal structure which is at odds with the published phase diagram for ambient crystal structure. The surface stability of Fe2P-TaN is assessed and the absorption enthalpy of Silver adatoms is calculated. Finally, the thermodynamic stability of the TaN-Ag interconnect system is assessed.
ContributorsGrumski, Michael (Author) / Adams, James (Thesis advisor) / Krause, Stephen (Committee member) / Alford, Terry (Committee member) / Arizona State University (Publisher)
Created2012
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As world energy demands increase, research into more efficient energy production methods has become imperative. Heterogeneous catalysis and nanoscience are used to promote chemical transformations important for energy production. These concepts are important in solid oxide fuel cells (SOFCs) which have attracted attention because of their potential to provide an

As world energy demands increase, research into more efficient energy production methods has become imperative. Heterogeneous catalysis and nanoscience are used to promote chemical transformations important for energy production. These concepts are important in solid oxide fuel cells (SOFCs) which have attracted attention because of their potential to provide an efficient and environmentally favorable power generation system. The SOFC is also fuel-flexible with the ability to run directly on many fuels other than hydrogen. Internal fuel reforming directly in the anode of the SOFC would greatly reduce the cost and complexity of the device. Methane is the simplest hydrocarbon and a main component in natural gas, making it useful when testing catalysts on the laboratory scale. Nickel (Ni) and gadolinium (Gd) doped ceria (CeO2) catalysts for potential use in the SOFC anode were synthesized with a spray drying method and tested for catalytic performance using partial oxidation of methane and steam reforming. The relationships between catalytic performance and structure were then investigated using X-ray diffraction, transmission electron microscopy, and environmental transmission electron microscopy. The possibility of solid solutions, segregated phases, and surface layers of Ni were explored. Results for a 10 at.% Ni in CeO2 catalyst reveal a poor catalytic behavior while a 20 at.% Ni in CeO2 catalyst is shown to have superior activity. The inclusion of both 10 at.% Gd and 10 at.% Ni in CeO2 enhances the catalytic performance. Analysis of the presence of Ni in all 3 samples reveals Ni heterogeneity and little evidence for extensive solid solution doping. Ni is found in small domains throughout CeO2 particles. In the 20 at.% Ni sample a segregated, catalytically active NiO phase is observed. Overall, it is found that significant interaction between Ni and CeO2 occurs that could affect the synthesis and functionality of the SOFC anode.
ContributorsCavendish, Rio (Author) / Crozier, Peter (Thesis advisor) / Adams, James (Committee member) / Smith, David (Committee member) / Arizona State University (Publisher)
Created2012
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As technological advancement increases and becomes more accessible to everyone around the world, many communities and support groups have begun to offer online options for their programs, whether it be a fitness program, online therapy group, or doctor’s appointment. With the COVID-19 pandemic affecting every country around the world, online

As technological advancement increases and becomes more accessible to everyone around the world, many communities and support groups have begun to offer online options for their programs, whether it be a fitness program, online therapy group, or doctor’s appointment. With the COVID-19 pandemic affecting every country around the world, online and virtual communities have become more necessary than ever. Using personal experience from an online fitness community formed as a response to social isolation called“Barrett Healthy Minds, Healthy Bodies,” research was conducted to determine if online communities had the same effectiveness as in-person communities in reaching and maintaining individual health goals. Peer-reviewed scientific articles and research papers from many countries around the world were analyzed for demonstration and quantification of the efficacy of other online communities compared to in- person groups. In addition, the benefits and limitations of online communities were identified. Using all of the research and data collected, a novel fitness program was designed for implementation with an online synchronous group (OSG) and an online asynchronous option serving as a control to observe any differential adherence of participants to fitness goals. The proposed OSG consists of meetings and workouts through Zoom and is more interactive, even virtually. The control group had no interaction with others and completed the workouts alone. While this program was not distributed to the public and tested as part of this project, it was designed to be an optimized pilot program to test the impact of remote community engagement on goal attainment. It is predicted that the OSG would demonstrate improvement over control in better reaching goals and increased satisfaction with results. Scientific literature from a variety of disciplines discussed here informs this prediction.

ContributorsKaroubi, Seema (Author) / Sellner, Erin (Thesis director) / Culbertson, Jade (Committee member) / School of Humanities, Arts, and Cultural Studies (Contributor) / School of Mathematical and Natural Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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This paper focuses on feudalist structure and values within this system in George R. R. Martin's fantasy novel series A Song of Ice and Fire and Shakespeare's play King Richard the Third. The paper is structured into three arguments that focus on different characters from each work. The first argument

This paper focuses on feudalist structure and values within this system in George R. R. Martin's fantasy novel series A Song of Ice and Fire and Shakespeare's play King Richard the Third. The paper is structured into three arguments that focus on different characters from each work. The first argument is focused on Tyrion Lannister and Richard III's deformity, and how they violate feudalist values. This argument ultimately comes to the discussion of whether or not these characters are monstrous and by what values. The second argument is focused on Daenerys Targaryen and Margaret, discussing why both authors give these women a supernatural power. The authors give women these powers because they believe that women should have power. Martin argues that women need to remake the structure, while Shakespeare believes women can change their place in the structure through collective action. The last argument focuses on Petyr Baelish and Richard III, and how they both represent a chaos attacking feudalism. Petyr is a chaos that comes outside the system, exploiting the values of the system, while Richard is a chaos within the system because he violates feudal values, while trying to hold positions where he needs to embody feudalist value. The authors come to different conclusions of what is trying to take down feudalist structure and how this could be fixed. Martin finds feudalism cannot be fixed and that other systems are not much better because they still create violence. Shakespeare comes to the conclusion that feudalism cannot be fixed because people continue to violate its values, so a new system must be put in place.
ContributorsPittaro, James Vincent (Author) / Mann, Annika (Thesis director) / Kirsch, Sharon (Committee member) / Barrett, The Honors College (Contributor) / School of Social and Behavioral Sciences (Contributor) / School of Humanities, Arts, and Cultural Studies (Contributor)
Created2015-05