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- Genre: Masters Thesis
- Creators: Arizona State University
- Creators: Chakraborty, Bijeta
- Member of: ASU Electronic Theses and Dissertations
Description
This research examined successful aging in a convenience sample of 14 women in Phoenix, Arizona. The study used a mixed methods approach involving individual interviews and administration of a standardized instrument designed to measure success using an alternative construct, gerotranscendence. Explorative questions were designed to gather data regarding diverse women's lived experiences. In order to examine the impact of lived experiences on successful aging, demographics were collected and participants were administered the gerotranscendence scale further revised. Findings reveal that when success is conceptualized using gerotranscendence theory, women of color may still appear less successful than their white counterparts. Narratives yielded rich data regarding the influence of factors such as care giving and violated expectations. This research helps to expand the knowledge base on factors that impact successful aging of diverse women. This research contributes to the field of social work by providing insight into the complex factors that impact diverse woman, which may aid in the empowerment of social workers to advocate for more effective macro interventions for diverse older women.
ContributorsRansom, Nicole (Author) / Bonifas, Robin (Thesis advisor) / Anthony, Elizabeth (Committee member) / Gustavson, Kristen (Committee member) / Arizona State University (Publisher)
Created2013
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
Welfare recipients must engage in a specified number of hours of work-based activities. Work-based activities include providing childcare for others, enrolling to obtain a GED, participating in job clubs, and working for pay. Welfare recipients may choose to get a GED or participate in job clubs to improve their chances of finding employment. As some states require participation in job clubs to receive welfare benefits, this study examined the likelihood of job club participation by low-income females in states where job club participation is optional, not mandatory. Using data from a sample of 3,642 low-income mothers participating in the Survey of Income and Program Participation (SIPP), I explored the relationship between educational attainment and the probability of attending job club or searches in the past month. Sociodemographic and state-level characteristics were used to control for other factors in logistic regression models. Results show that low-income women with higher educational attainment were more likely to attend a job club. Other significant factors were marital status, metropolitan residence, number of children, number of family members, and state poverty rate. Policy implications suggest that attendees already have the necessary skills to obtain a job and time limits and enrollment caps may hinder the changes of the targeted population.
ContributorsYim, Gloria T (Author) / Hayford, Sarah (Thesis advisor) / Peck, Laura (Committee member) / Yabiku, Scott (Committee member) / Arizona State University (Publisher)
Created2011
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
Through critical discourse analysis, this thesis explores the construction of poverty and development within and across the United Nations Millennium Development Goals and the proposed post-2015 Sustainable Development Goals texts. The proposed post-2015 Sustainable Development Goals frame the international development landscape for the next 15 years, therefore it becomes imperative for civil society to understand their dominant economic schemes for poverty alleviation in order to adopt or oppose similar methods of poverty abatement. Deductively, this thesis investigates Keynesianism and neoliberalism, the dominant economic discourses whose deployments within the goals have shaped transnational frameworks for interpreting and mitigating poverty. It assesses the failures of the Millennium Development Goals, as articulated both by its creators and critics, and evaluates the responsiveness of the United Nations in the constitution of the proposed post-2015 Sustainable Development Goals in relation to these critiques through the lens of liberal feminist and World Social Forum discourses. These activist and oppositional social discourses embody competing values, representations, and problem-solution frames that challenge and resist the dominant economic discourses in both sets of goals. Additionally, this thesis uses an inductive approach to critically analyze both sets of goals in order to identify any emergent discursive frameworks grounded in each text that assist in understanding the problems of, and solutions to, poverty.
ContributorsBriant, Janie (Author) / Nadesan, Majia (Thesis advisor) / Kelley, Douglas L. (Committee member) / Keahey, Jennifer (Committee member) / Arizona State University (Publisher)
Created2015
Description
ABSTRACT
As a graduate student earning both a Master of Arts in Social Justice and Human Rights and a Graduate Certificate in Nonprofit Leadership Management, I have tried to bridge the theoretical and the empirical in a meaningful way. A problematic chasm between the nonprofit professional and the client being served existed, and I wanted to research this chasm. I wanted to understand what challenges a woman of color faced if she was both a client and a nonprofit professional, possessing dual identities and engaging in a sort of welfare system border crossing. There was a gap in the academic research on women in the nonprofit sector, more specifically the charitable, human services sector, and there was little to no research on women who have been both clients and caseworkers. Therefore, I conducted a series five of in-depth, semi-structured interviews with women of color working at a local food bank. As an employee of the food bank, I recorded my own observations and field notes in order to write a feminist institutional ethnography. I employed interpretive, less conventional design methods, which were aligned with my commitment to social justice. The research highlighted many negative stories about oppression and exclusion women faced in the nonprofit sector. It also confronted the problematic stereotype welfare recipients, specifically women of color, are faced with as a result of the politics of disgust and dominant myth of the Welfare Queen. The research sought to explain how and why women of color transition in and out of the welfare state, and how they manage to work within a food bank, where they are constantly surrounded by inequalities.
As a graduate student earning both a Master of Arts in Social Justice and Human Rights and a Graduate Certificate in Nonprofit Leadership Management, I have tried to bridge the theoretical and the empirical in a meaningful way. A problematic chasm between the nonprofit professional and the client being served existed, and I wanted to research this chasm. I wanted to understand what challenges a woman of color faced if she was both a client and a nonprofit professional, possessing dual identities and engaging in a sort of welfare system border crossing. There was a gap in the academic research on women in the nonprofit sector, more specifically the charitable, human services sector, and there was little to no research on women who have been both clients and caseworkers. Therefore, I conducted a series five of in-depth, semi-structured interviews with women of color working at a local food bank. As an employee of the food bank, I recorded my own observations and field notes in order to write a feminist institutional ethnography. I employed interpretive, less conventional design methods, which were aligned with my commitment to social justice. The research highlighted many negative stories about oppression and exclusion women faced in the nonprofit sector. It also confronted the problematic stereotype welfare recipients, specifically women of color, are faced with as a result of the politics of disgust and dominant myth of the Welfare Queen. The research sought to explain how and why women of color transition in and out of the welfare state, and how they manage to work within a food bank, where they are constantly surrounded by inequalities.
ContributorsRoland, Kimberly (Author) / Behl, Natasha (Thesis advisor) / Murphy Erfani, Julie (Committee member) / Elenes, C. Alejandra (Committee member) / Arizona State University (Publisher)
Created2015
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
Low income, pregnant adolescents have an increased risk of adverse pregnancy outcomes, such as preterm birth, delivery of low birth weight babies and excessive gestational weight gain that increases the risk of postpartum overweight and obesity. Inadequate dietary intake is a modifiable risk factor that may differentially impact maternal health and fetal outcomes for pregnant adults and adolescents. To evaluate the effectiveness of a social media intervention on improving prenatal health knowledge and dietary intake, 22 racially diverse pregnant women (59% Black and 36% White) were recruited and adolescent (n=10) outcomes compared to those of adults (n=12) across the intervention. Pre- and post-intervention nutrition knowledge questionnaires and diet recalls were completed to assess nutrition knowledge and dietary intake. When assessing dietary change across the intervention, significant decreases in fat (pre vs. post, 97.9 ± 0.2 g vs. 90.2 ± 0.2 g, P=0.047) and folate intake (pre vs. post, 537.6 ± 0.3 μg vs. 531.2 ± 0.2 μg, P=0.041) were observed while significant increases in carbohydrate (pre vs. post, 318.9 ± 0.2 g vs. 335.9 ± 0.2 g, P<0.001), calcium (pre vs. post, 851.3 ± 0.3 mg vs. 893.5 ± 0.2 mg, P<0.001) and magnesium intakes (pre vs. post, 212.9 ± 0.2 mg vs. 227.8 ± 0.2 mg, P<0.001) occurred. These time effects occurred independent of group (adolescents vs. adults) as time*group interactions were not significant (p>0.05) with the exception of sugar intake. Increases in sugar intake across the intervention were greater among the adolescent group (adolescent vs. adult, 7.9 ± 0.2 g vs. 6.0 ± 0.2 g, P=0.023). Overall nutrition knowledge was limited and confusion regarding MyPlate recommendations persisted. The inadequate dietary behaviors observed suggest that future interventions should focus education on specific dietary nutrients such as added sugars and fiber to improve dietary intakes. The best way to actively engage pregnant adolescents is unknown: however, social media has the potential to reach teens and low-income women with education that may be key in allowing interventions to change dietary habits and behaviors.
ContributorsEllis, Megan (Author) / Whisner, Corrie M (Thesis advisor) / Bruening, Meg (Committee member) / Vega-Lopez, Sonia (Committee member) / Arizona State University (Publisher)
Created2016