Matching Items (198)
Description
Over 150 years since the abolition of slavery, African Americans still lack equal access to education and other quality of life markers. However, a slow increase in African American students pursuing and obtaining higher education demonstrates the progress of African American academic success. Although still not at an equitable level, this progress, and the voices of success are often muted by the majoritarian narrative of African American student failure. This research focuses on African American student success and examines the specific socio-cultural characteristics and processes that shape the ways in which African American students develop their own counter-narratives to persist and gain access to higher education. This study utilizes narrative inquiry in the form of interviews, artifacts collection and student-drawn identity maps to understand the factors that influence the development of counter-narratives. The primary research questions included: What narratives did African American students tell themselves to help them persist in school, attain a high school diploma and pursue higher education? How did they develop their narratives? How did their narratives influence their educational experiences? Five African American students who attended an elite public university in the southwest United States participated in four to five interviews ranging from six to ten hours in total. Through the analysis of their stories, the importance of culture and context were clear. Specifically their social support systems including their parents, siblings, teachers and mentors, significantly influenced their identity development and human agency. The findings also point to a critical path forward: if society commits to supporting African American student success, then shine a light on stories of persistence and potential rather than shortcomings and failures.
ContributorsFreeman, Stacey Vicario (Author) / Kozleski, Elizabeth B. (Thesis advisor) / Fischman, Gustavo (Thesis advisor) / Artiles, Alfredo (Committee member) / Arizona State University (Publisher)
Created2016
Description
Improving energy efficiency has always been the prime objective of the custom and automated digital circuit design techniques. As a result, a multitude of methods to reduce power without sacrificing performance have been proposed. However, as the field of design automation has matured over the last few decades, there have been no new automated design techniques, that can provide considerable improvements in circuit power, leakage and area. Although emerging nano-devices are expected to replace the existing MOSFET devices, they are far from being as mature as semiconductor devices and their full potential and promises are many years away from being practical.
The research described in this dissertation consists of four main parts. First is a new circuit architecture of a differential threshold logic flipflop called PNAND. The PNAND gate is an edge-triggered multi-input sequential cell whose next state function is a threshold function of its inputs. Second a new approach, called hybridization, that replaces flipflops and parts of their logic cones with PNAND cells is described. The resulting \hybrid circuit, which consists of conventional logic cells and PNANDs, is shown to have significantly less power consumption, smaller area, less standby power and less power variation.
Third, a new architecture of a field programmable array, called field programmable threshold logic array (FPTLA), in which the standard lookup table (LUT) is replaced by a PNAND is described. The FPTLA is shown to have as much as 50% lower energy-delay product compared to conventional FPGA using well known FPGA modeling tool called VPR.
Fourth, a novel clock skewing technique that makes use of the completion detection feature of the differential mode flipflops is described. This clock skewing method improves the area and power of the ASIC circuits by increasing slack on timing paths. An additional advantage of this method is the elimination of hold time violation on given short paths.
Several circuit design methodologies such as retiming and asynchronous circuit design can use the proposed threshold logic gate effectively. Therefore, the use of threshold logic flipflops in conventional design methodologies opens new avenues of research towards more energy-efficient circuits.
The research described in this dissertation consists of four main parts. First is a new circuit architecture of a differential threshold logic flipflop called PNAND. The PNAND gate is an edge-triggered multi-input sequential cell whose next state function is a threshold function of its inputs. Second a new approach, called hybridization, that replaces flipflops and parts of their logic cones with PNAND cells is described. The resulting \hybrid circuit, which consists of conventional logic cells and PNANDs, is shown to have significantly less power consumption, smaller area, less standby power and less power variation.
Third, a new architecture of a field programmable array, called field programmable threshold logic array (FPTLA), in which the standard lookup table (LUT) is replaced by a PNAND is described. The FPTLA is shown to have as much as 50% lower energy-delay product compared to conventional FPGA using well known FPGA modeling tool called VPR.
Fourth, a novel clock skewing technique that makes use of the completion detection feature of the differential mode flipflops is described. This clock skewing method improves the area and power of the ASIC circuits by increasing slack on timing paths. An additional advantage of this method is the elimination of hold time violation on given short paths.
Several circuit design methodologies such as retiming and asynchronous circuit design can use the proposed threshold logic gate effectively. Therefore, the use of threshold logic flipflops in conventional design methodologies opens new avenues of research towards more energy-efficient circuits.
ContributorsKulkarni, Niranjan (Author) / Vrudhula, Sarma (Thesis advisor) / Colbourn, Charles (Committee member) / Seo, Jae-Sun (Committee member) / Yu, Shimeng (Committee member) / Arizona State University (Publisher)
Created2015
Description
The purposes of this study were (1) to examine the direct and indirect effect of school-level testing policies on reading achievement though changes in amount and types of reading instruction, (2) to investigate the reading trajectories moderated by school-level testing policies longitudinally, and (3) to examine the relationship between testing policies and the achievement gap by exploring whether certain student characteristics moderate the relationship between testing policy and reading achievement, using Early Childhood Longitudinal Study Kindergarten (ECLS-K) Cohort of 2010-2011 data. Findings from a multilevel full structural mediation model suggest that school-level frequency of state/local standardized tests had an indirect effect on student reading achievement through changes in both amount and the types of instruction at the school-level (cross-sectional fall kindergarten sample =12,241 children nested in 1,067 kindergarten classes). The findings from a three-level growth models indicated only children of Asian background and children from high socio-economic backgrounds who had frequent standardized tests in kindergarten accelerated in their monthly reading growth, whereas other children (e.g., low SES, non-Asian children) did not show any changes in the rate of the reading growth (longitudinal sample from fall of kindergarten to spring of first grade = 7,392 children nested in 744 kindergartens). The findings from the current study suggest that testing policy is not an effective means to reduce the achievement gap of children from disadvantaged family backgrounds, underperforming children or that children from low socieo-economic backgrounds. These children did not seem to benefit from frequent standardized tests longitudinally. Implications for supporting school assessment practices and instruction are discussed.
ContributorsIm, Haesung (Author) / Nakagawa, Kathryn (Thesis advisor) / Thompson, Marilyn (Committee member) / Swadener, Elizabeth (Committee member) / Iida, Masumi (Committee member) / Arizona State University (Publisher)
Created2015
Description
Register file (RF) memory is important in low power system on chip (SOC) due to its
inherent low voltage stability. Moreover, designs increasingly use compiled instead of custom memory blocks, which frequently employ static, rather than pre-charged dynamic RFs. In this work, the various RFs designed for a microprocessor cache and register files are discussed. Comparison between static and dynamic RF power dissipation and timing characteristics is also presented. The relative timing and power advantages of the designs are shown to be dependent on the memory aspect ratio, i.e. array width and height.
inherent low voltage stability. Moreover, designs increasingly use compiled instead of custom memory blocks, which frequently employ static, rather than pre-charged dynamic RFs. In this work, the various RFs designed for a microprocessor cache and register files are discussed. Comparison between static and dynamic RF power dissipation and timing characteristics is also presented. The relative timing and power advantages of the designs are shown to be dependent on the memory aspect ratio, i.e. array width and height.
ContributorsVashishtha, Vinay (Author) / Clark, Lawrence T. (Thesis advisor) / Seo, Jae-Sun (Committee member) / Ogras, Umit Y. (Committee member) / Arizona State University (Publisher)
Created2014
Description
Over the past several years, the density of integrated circuits has been increasing at a very fast rate, following Moore’s law. The advent of three dimensional (3D) packaging technologies enable the increase in density of integrated circuits without necessarily shrinking the dimensions of the device. Under such constraints, the solder volume necessary to join the various layers of the package is also extremely small. At smaller length scales, the local cooling rates are higher, so the microstructures are much finer than that obtained in larger joints (BGA, C4). The fraction of intermetallic compounds (IMCs) present in solder joints in these volumes will be larger. The Cu6Sn5 precipitate size and spacing, and Sn grain structure and crystallography will be different at very small volumes. These factors will most certainly affect the performance of the solder. Examining the mechanical behavior and reliability of Pb-free solders is difficult, primarily because a methodology to characterize the microstructure and the mechanics of deformation at these extremely small length scales has yet to be developed.
In this study, Sn grain orientation and Cu6Sn5 IMC fraction, size, and morphology are characterized in 3D, in pure Sn based solder joints. The obtained results show differences in morphology of Sn grains and IMC precipitates as a function of location within the solder joint indicating influence of local cooling rate differences. Ex situ and in situ electromigration tests done on 250 um and 500 um pure Sn solder joints elucidate the evolution of microstructure, specifically Sn grain growth, IMC segregation and surface degradation. This research implements 3D quantification of microstructural features over micro and nano-scales, thereby enabling a multi-scale / multi-characterization approach.
In this study, Sn grain orientation and Cu6Sn5 IMC fraction, size, and morphology are characterized in 3D, in pure Sn based solder joints. The obtained results show differences in morphology of Sn grains and IMC precipitates as a function of location within the solder joint indicating influence of local cooling rate differences. Ex situ and in situ electromigration tests done on 250 um and 500 um pure Sn solder joints elucidate the evolution of microstructure, specifically Sn grain growth, IMC segregation and surface degradation. This research implements 3D quantification of microstructural features over micro and nano-scales, thereby enabling a multi-scale / multi-characterization approach.
ContributorsKirubanandham, Antony (Author) / Chawla, Nikhilesh (Thesis advisor) / Jiao, Yang (Committee member) / Lu, Minhua (Committee member) / Rajagopalan, Jagannathan (Committee member) / Arizona State University (Publisher)
Created2016
Description
This phenomenological study explores the question: What are the lived experiences of Arizonans who identify their gender identities as ‘non-binary’? (‘non-binary’ defined here as anyone who identifies their gender as something other than ‘always and exclusively male or always and exclusively female’). The study explores the lived realities of four non-binary identified transgender people living in Arizona. Each participant took a short survey and conducted a 45-minute in-person interview, conducted through phenomenological questioning to evoke deep descriptions of experience. After analyzing the results through feminist hermeneutic phenomenology, this study suggests that the experience of non-binary gender identity presents an essential pattern of cultivating self-realization. The essential themes of internal recognition, external presentation, and movement toward wellness fell into this pattern. The United States has conceptualized transgender identity in many ways, from pathologizing to politicizing, to medically affirming views. Although the literature on this topic is quite small, there is no doubt that non-binary transgender people exist in U.S. public life. Ultimately, if non-binary people are to find affirming paths toward self-realization, they must be heard from their own experiences in their own voices.
ContributorsSkinner, Ashton (Author) / Sandlin, Jennifer (Thesis advisor) / Nakagawa, Kathryn (Committee member) / Santos, Carlos (Committee member) / Arizona State University (Publisher)
Created2017
Description
Definitions of quality child care are subjective, depending on who is defining quality, and constructions of quality remain a contested issue in the early childhood field. There are multiple ways of defining quality child care, most of which are from the perspectives of researchers, policymakers, and professionals. Few studies of child care quality take into consideration parents’ perspectives of what quality child care means to them and what they deem as important for the wellbeing of their children (Ceglowski & Davis, 2004, Duncan et al., 2004, Harrist et al., 2007, & Liu et al., 2004). This study compared parent perspectives to criteria for assessing child care used in Quality First, a statewide quality improvement and rating system for providers of center-based or home-based early care and education, to better understand the gaps drawing from ecological theory (refs – add these) and discuss the consequences of these different perspectives.
This study utilized a comparative qualitative analysis of ways in which parents and state agencies view determinants of child care quality. The data for this study were collected from interview responses to open-ended questions on a larger mixed-method study with parents of children under the age of 6 from the Central Arizona area. The quality indicators used by Quality First included the Infant/Toddler Environment Rating Scale (ITERS-R), Early Childhood Environment Rating Scale (ECERS-R), Family Child Care Environment Rating Scale (FCCERS-R), and the Classroom Assessment Scoring System (CLASS), which were analyzed and compared to parent descriptions of quality factors in child care.
The findings of this study contribute to the discussion of ways in which parents’ perspectives are similar and different to that of quality rating scales, in this case those used by Quality First, and how the gap may be contributing to unintended consequences. In the study, I noticed that parents were more inclined toward affect qualities as quality indicators whereas the Quality First had more structural qualities as quality indicators. This led to the addressing of the need to bridge this gap to have a more comprehensive understanding of quality child care to meet different needs as identified by parents and professionals.
This study utilized a comparative qualitative analysis of ways in which parents and state agencies view determinants of child care quality. The data for this study were collected from interview responses to open-ended questions on a larger mixed-method study with parents of children under the age of 6 from the Central Arizona area. The quality indicators used by Quality First included the Infant/Toddler Environment Rating Scale (ITERS-R), Early Childhood Environment Rating Scale (ECERS-R), Family Child Care Environment Rating Scale (FCCERS-R), and the Classroom Assessment Scoring System (CLASS), which were analyzed and compared to parent descriptions of quality factors in child care.
The findings of this study contribute to the discussion of ways in which parents’ perspectives are similar and different to that of quality rating scales, in this case those used by Quality First, and how the gap may be contributing to unintended consequences. In the study, I noticed that parents were more inclined toward affect qualities as quality indicators whereas the Quality First had more structural qualities as quality indicators. This led to the addressing of the need to bridge this gap to have a more comprehensive understanding of quality child care to meet different needs as identified by parents and professionals.
ContributorsCharania, Sharmeen (Author) / Swadener, Beth B (Thesis advisor) / Nakagawa, Kathryn (Committee member) / Arzubiaga, Angela (Committee member) / Arizona State University (Publisher)
Created2014
Geographical Influences on Parental Decision for Child's Secondary Education from a Race Perspective
Description
The objective of this research project was to explore how lower-income, Latinx parents make decisions about where their child will attend high school and the factors that influence choosing out-of-district or in-district (public, charter or private) high schools. Research on parental choice of schooling often finds that parents’ education and income make a difference in school choice decisions with higher-income parents relying more on social networks for information and lower-income parents relying more on school-based information (e.g., Bosetti, 2004; Holme, 2002). Researchers have also found that how information is presented and understood also plays a part in school choice (IES, 2018).
However, less information is available on how Latinx parents receive information and the factors that play a part in their schooling decisions. This project focused on how Latinx parents weight information about their local high schools versus other school choices. The research revolving around Latinx families and high school choice matters because most research in the education sector does not involve minority groups, such as the Latinx and Hispanic communities specifically in Laveen. The key research questions are: Why do Latinx parents send their children to in-district high schools when those schools have poorer test scores? Why do parents send their children out of district high schools? What information and resources are used by parents to help make their decision in the process? How do student perspectives play a part in the decision?
Data was gathered through an on-line survey of parents about factors that play a part in the choice of high school. In-person case studies of four families also showed the detail of the specific ways that sources of information, personal networks, child input, and other factors influence the school choice process. I found that parents sent their children to their designated in-district high school because it was the closest available option that led to the most convenience in regards to commuting. On the other hand, I found that parents sent their child to an out of district high school because of the resources they used, which consisted of mostly family and other social networks that had attended or were currently attending that high school. Overall, the students’ perspective at the time when the decision was made played an important role in almost all of the case studies. All of the children were included at least somewhat and their input was taken into consideration if and when possible. Also, a geographical analysis of Laveen that includes the income levels, education levels, and high schools available in the area is interpreted. Through the maps completed by Social Explorer, the data used is from 2018, and it was filtered from the Hispanic population in Laveen from the non-Hispanic population to add more emphasis on a specific ethnicity.
However, less information is available on how Latinx parents receive information and the factors that play a part in their schooling decisions. This project focused on how Latinx parents weight information about their local high schools versus other school choices. The research revolving around Latinx families and high school choice matters because most research in the education sector does not involve minority groups, such as the Latinx and Hispanic communities specifically in Laveen. The key research questions are: Why do Latinx parents send their children to in-district high schools when those schools have poorer test scores? Why do parents send their children out of district high schools? What information and resources are used by parents to help make their decision in the process? How do student perspectives play a part in the decision?
Data was gathered through an on-line survey of parents about factors that play a part in the choice of high school. In-person case studies of four families also showed the detail of the specific ways that sources of information, personal networks, child input, and other factors influence the school choice process. I found that parents sent their children to their designated in-district high school because it was the closest available option that led to the most convenience in regards to commuting. On the other hand, I found that parents sent their child to an out of district high school because of the resources they used, which consisted of mostly family and other social networks that had attended or were currently attending that high school. Overall, the students’ perspective at the time when the decision was made played an important role in almost all of the case studies. All of the children were included at least somewhat and their input was taken into consideration if and when possible. Also, a geographical analysis of Laveen that includes the income levels, education levels, and high schools available in the area is interpreted. Through the maps completed by Social Explorer, the data used is from 2018, and it was filtered from the Hispanic population in Laveen from the non-Hispanic population to add more emphasis on a specific ethnicity.
ContributorsRodriguez, Briana (Author) / Nakagawa, Kathryn (Thesis director) / Shabazz, Rashad (Committee member) / Sanford School of Social and Family Dynamics (Contributor) / School of Social Transformation (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05