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- Genre: Masters Thesis
- Creators: Arizona State University
- Creators: Chakraborty, Bijeta
- Member of: ASU Electronic Theses and Dissertations
Description
Using integrated threat theory as the theoretical framework, this study examines the impact of perceived realistic threats (threats to welfare) and symbolic threats (threats to worldview) on anti-immigrant sentiment among a nationally representative sample in the U.S. Analysis of the antecedents of prejudice is particularly relevant today as anti-immigrant sentiment and hostile policies toward the population have risen in the past two decades. Perceived discrimination has also become salient within immigrant communities, negatively impacting both mental and physical health. Using logistic ordinal regressions with realistic threat, symbolic threat, and immigrant sentiment scales, this study found that both realistic and symbolic threats increased participants' likelihood of selecting a higher level of anti-immigrant sentiment, suggesting both are predictive of prejudice. However, symbolic threats emerged as a greater predictor of anti-immigrant sentiment, with an effect size over twice that of realistic threats. Implications for social work policy, practice, and future research are made.
ContributorsKiehne, Elizabeth (Author) / Becerra, David (Thesis advisor) / Segal, Elizabeth (Committee member) / Androff, David K. (Committee member) / Arizona State University (Publisher)
Created2014
Description
Efficiency of components is an ever increasing area of importance to portable applications, where a finite battery means finite operating time. Higher efficiency devices need to be designed that don't compromise on the performance that the consumer has come to expect. Class D amplifiers deliver on the goal of increased efficiency, but at the cost of distortion. Class AB amplifiers have low efficiency, but high linearity. By modulating the supply voltage of a Class AB amplifier to make a Class H amplifier, the efficiency can increase while still maintaining the Class AB level of linearity. A 92dB Power Supply Rejection Ratio (PSRR) Class AB amplifier and a Class H amplifier were designed in a 0.24um process for portable audio applications. Using a multiphase buck converter increased the efficiency of the Class H amplifier while still maintaining a fast response time to respond to audio frequencies. The Class H amplifier had an efficiency above the Class AB amplifier by 5-7% from 5-30mW of output power without affecting the total harmonic distortion (THD) at the design specifications. The Class H amplifier design met all design specifications and showed performance comparable to the designed Class AB amplifier across 1kHz-20kHz and 0.01mW-30mW. The Class H design was able to output 30mW into 16Ohms without any increase in THD. This design shows that Class H amplifiers merit more research into their potential for increasing efficiency of audio amplifiers and that even simple designs can give significant increases in efficiency without compromising linearity.
ContributorsPeterson, Cory (Author) / Bakkaloglu, Bertan (Thesis advisor) / Barnaby, Hugh (Committee member) / Kiaei, Sayfe (Committee member) / Arizona State University (Publisher)
Created2013
Description
Class D Amplifiers are widely used in portable systems such as mobile phones to achieve high efficiency. The demands of portable electronics for low power consumption to extend battery life and reduce heat dissipation mandate efficient, high-performance audio amplifiers. The high efficiency of Class D amplifiers (CDAs) makes them particularly attractive for portable applications. The Digital class D amplifier is an interesting solution to increase the efficiency of embedded systems. However, this solution is not good enough in terms of PWM stage linearity and power supply rejection. An efficient control is needed to correct the error sources in order to get a high fidelity sound quality in the whole audio range of frequencies. A fundamental analysis on various error sources due to non idealities in the power stage have been discussed here with key focus on Power supply perturbations driving the Power stage of a Class D Audio Amplifier. Two types of closed loop Digital Class D architecture for PSRR improvement have been proposed and modeled. Double sided uniform sampling modulation has been used. One of the architecture uses feedback around the power stage and the second architecture uses feedback into digital domain. Simulation & experimental results confirm that the closed loop PSRR & PS-IMD improve by around 30-40 dB and 25 dB respectively.
ContributorsChakraborty, Bijeta (Author) / Bakkaloglu, Bertan (Thesis advisor) / Garrity, Douglas (Committee member) / Ozev, Sule (Committee member) / Arizona State University (Publisher)
Created2012
Description
ABSTRACT This study focuses on second language acquisition process amongst East Asian adult learners at an English and Culture Acquisition Program (ECAP) classroom. To understand their English learning experience, this study employs classroom observation, participant interview and document collection as research methods. The findings of this work suggest that ECAP does intend to help learners acquire English language proficiency in ways that were responsive to both the sociocultural backgrounds and individual needs of participants. ECAP also respects and promotes the learners' autonomy in the learning process. However, the program administrators and teachers still need to deepen their understanding of East Asian learners' sociocultural heritage and individual needs and improve facilitation accordingly.
ContributorsMi, Ximin (Author) / Danzig, Arnold (Thesis advisor) / Ovando, Carlos (Committee member) / Szecsy, Elsie (Committee member) / Arizona State University (Publisher)
Created2011
Description
In this thesis, a digital input class D audio amplifier system which has the ability
to reject the power supply noise and nonlinearly of the output stage is presented. The main digital class D feed-forward path is using the fully-digital sigma-delta PWM open loop topology. Feedback loop is used to suppress the power supply noise and harmonic distortions. The design is using global foundry 0.18um technology.
Based on simulation, the power supply rejection at 200Hz is about -49dB with
81dB dynamic range and -70dB THD+N. The full scale output power can reach as high as 27mW and still keep minimum -68dB THD+N. The system efficiency at full scale is about 82%.
to reject the power supply noise and nonlinearly of the output stage is presented. The main digital class D feed-forward path is using the fully-digital sigma-delta PWM open loop topology. Feedback loop is used to suppress the power supply noise and harmonic distortions. The design is using global foundry 0.18um technology.
Based on simulation, the power supply rejection at 200Hz is about -49dB with
81dB dynamic range and -70dB THD+N. The full scale output power can reach as high as 27mW and still keep minimum -68dB THD+N. The system efficiency at full scale is about 82%.
ContributorsBai, Jing (Author) / Bakkaloglu, Bertan (Thesis advisor) / Arizona State University (Publisher)
Created2015
Description
Political party identification has an immense influence on shaping individual attitudes and processes of reasoning to the point where otherwise knowledgeable people endorse political conspiracies that support one's political in-group and simultaneously disparage an out-group. Although recent research has explored this tendency among partisans, less is known about how Independents respond in comparison. Previous research fails to identify the Independent as a unique type of voter, but rather categorizes this group as ostensibly partisan, not a separate phenomenon to investigate. However, most Independents purport neutrality and, by recent polls, are becoming a substantial body worthy of concerted focus. Many questions arise about who Independents really are. For example, do all who identify as Independent behave in a similar manner? Are Independents ideologically different than what is represented by a partisan label? Is the Independent category a broad term for something entirely misunderstood? A thorough investigation into the greater dynamics of the political environment in the United States is an enormous undertaking, requiring a robust interdisciplinary approach beyond the focus and intent of this study. Therefore, this study begins the journey toward understanding these phenomena; do Independents, as a whole, uniformly respond to statements about political conspiracy theories? To explore these possibilities, explicit responses are bypassed to evaluate the implicit appeal of political conspiracy theories. An action dynamics (mouse-tracking) approach, a data rich method that records the response process, demonstrates Independents are not in fact a homogeneous group, but rather seem to fall into two groups: non-partisan leaning and partisan leaning. The analysis exposes that relative to the baseline and control stimuli: (1) Non-leaning Independents reveal an increased susceptibility to implicitly endorse bi-partisan directed conspiracy theories when compared to leaners. (2) Republican-leaners demonstrate a stronger susceptibility to endorse right-wing aligned conspiracy theories (against Barack Obama), similar to Republican partisans. (3) Democrat-leaners, unlike Democrat partisans, do not demonstrate any particular susceptibility to implicitly endorse either right/left-wing aligned conspiracy theories (against Barack Obama or George W. Bush). Drawing from major theories from social, political, and cognitive psychology will contribute to an understanding of these phenomena. Concluding remarks include study limitations and future directions.
ContributorsJohnson, Chelsea (Author) / Duran, Nicholas D (Thesis advisor) / Robles-Sotelo, Elias (Committee member) / Hall, Deborah (Committee member) / Arizona State University (Publisher)
Created2017
Description
ABSTRACT This thesis analyzes the discourse surrounding proposed solutions to the immigration phenomenon in the United States. I conducted two qualitative media analyses on the rhetoric and conceptual frames found in mass media newscasts reporting on the immigration debate. The first analysis covered the general immigration debate and the second covered the appearance of American southwest ranchers. Specifically the analyses contrasted the media's coverage of root economic causes to the immigration phenomenon in comparison to reactionary solutions as proposed by leading immigrant attrition organizations such as the immigration think tank, Federation for American Immigration Reform (FAIR) and Republican linguist, Frank Luntz. The main argument of this thesis is based on an analysis of how the media has used southwestern ranchers as expert witnesses for reactionary solutions on a national level. An acute qualitative media analysis was used to compare the rhetoric found in the media coverage of southwestern ranchers versus the rhetoric found in 12 in-depth interviews I conducted with ranchers in the American southwest. This thesis contends that the media has successfully turned southwestern ranchers into spokespersons for border security rhetoric, furthering the binary debates on border security and immigration reform and thus obscuring the conditions which force migrants to leave their home countries. The grounding theoretical framework for this thesis is based on David Altheide's qualitative media analysis which identifies how certain frames and common narratives ultimately construct a way of discussing the problem or the kind of discourse that will follow. This was structured on Atheide's qualitative media analysis protocols to dissect mass media newscasts covering the immigration debate and more specifically the mass media's coverage of southwestern ranchers. The qualitative media analyses were employed to determine whether the discourse found in nightly newscasts falls in line with root causes of immigration or FAIR's concern with reactionary solutions. To further assess the media's ability to shape discourse, and ultimately policy, these qualitative analyses were compared with in-depth interviews of the ranchers.
ContributorsFuente, Nicolás Antonio de la (Author) / Téllez, Michelle (Thesis advisor) / Stancliff, Michael (Committee member) / Gomez, Alan (Committee member) / Arizona State University (Publisher)
Created2010
Description
During the mid-1930s in Cuba, Ernest Hemingway befriended Cuban artist Antonio Gattorno (1904-1980) during Hemingway's most active period of Gulf Stream fishing trips. Their relationship soon transcended ocean sojourns, and the two exchanged letters, eight of which reside in the Hemingway Collection at the J.F.K. Library in Boston. Written between 1935 and 1937, the Hemingway-Gattorno correspondence showcases the relationship that came to fruition between the American writer and Cuban artist in the 1930s. It also presents a lens through which to examine the cultural contact that occurred between Americans and Cubans during a decade of great political, social, and economic exchange between the two nations. In addition, the Hemingway-Gattorno correspondence elucidates each country's tendency to romanticize the other before the Cuban Revolution and provides a template with which to examine current U.S.-Cuban relationships today. This thesis endeavors to first discuss the Hemingway-Gattorno relationship via a close examination of the correspondence that occurred between them. It then attests that the Hemingway-Gattorno correspondence exemplifies the transatlantic glamorization that characterized pre-revolutionary U.S.-Cuban relations. The thesis explores the replay of this act of romanticizing in real time, arguing that despite governmental injunctions since 1961, Americans and Cubans alike have continued to ingeniously find ways to communicate with one another in much the same way Hemingway and Gattorno did in the 1930s. One mechanism for doing so is remembering Ernest Hemingway's life in Cuba and the home he owned there, Finca Vigía, a performance of memory that often occurs through the conduits of either the Hemingway Archives in Boston or the Finca Vigía Museum in Cuba. American and Cuban longing for the cultural contact enjoyed by Hemingway and Gattorno is expressed and performed through a glorification of Hemingway and the Finca Vigía, despite the severance of diplomatic relations between the two countries in 1961. In addition, for Cubans in particular, Hemingway and the Finca Vigía present an opportunity to imagine the much more unified pre-revolutionary Cuba. Although certainly Hemingway and his home represent different realities for Cubans and Americans, in all, the thesis will show that citizens from both countries continue to find ways to create and imagine themselves in pre-revolutionary contexts like those embodied by Hemingway and Gattorno in the 1930s.
ContributorsDriscoll, Sarah (Author) / Horan, Elizabeth (Thesis advisor) / Sadowski-Smith, Claudia (Committee member) / Tobin, Beth (Committee member) / Arizona State University (Publisher)
Created2011