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- Genre: Masters Thesis
- Creators: Arizona State University
- Creators: Chakraborty, Bijeta
- Creators: Peterson, Cory
- Member of: ASU Electronic Theses and Dissertations
Description
This research is focused on competitive female video gamers. This study focuses on a specific group of competitive female gamers who participate in an all female online community group or clan known as the PMSclan. The purpose of the study is to analyze the highly competitive female video gaming clan members of the PMSclan in order to understand how resistance is displayed in a female centered video gaming community and how that affects the identity of the individual gamers through Shaw's (2001) theory of resistance. This study employs qualitative research design and uses content analysis of publicly available clan doctrines and member blogs through the PMSclan website. Findings indicate that collective acts of resistance lead to individual acts of resistance which can be seen through self-expression, self-determination, and empowerment. These acts of resistance have a positive impact on female gamers with outcomes of strength and power which can be displayed in a typically masculine society.
ContributorsPeña, Siobhan Jennell (Author) / Rodriguez, Ariel (Thesis advisor) / Knopf, Richard (Committee member) / Hayes, Elisabeth (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
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
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
The present study explored memorable messages that professional female athletes have recalled throughout their careers. This study sought to understand what types of memorable messages are recalled by female athletes that have made it to the top of their sports at the professional level and to understand whether the recalled memorable messages were gendered or not. Respondents were asked via a survey questionnaire to recall a memorable message, describe the meaning and context of the message and finally what effect, if any, the message had on them. Qualitative survey questionnaire responses were analyzed using thematic analysis. Results indicated that memorable messages were not gendered in any way but there were several relevant themes, which included: wisdom, performance, instruction, motivation, dedication and identity. These results are new to the field of memorable messages within the field of sport and hold significance for future research.
ContributorsMatthews, Robyn J. H (Author) / Kassing, Jeffrey (Thesis advisor) / Mean, Lindsey (Committee member) / Waldron, Vincent (Committee member) / Arizona State University (Publisher)
Created2016
Description
The gender gap of women in science is an important and unresolved issue in higher education and occupational opportunities. The present study was motivated by the fact that there are typically fewer females than males advancing in science, and therefore fewer female science instructor role models. This observation inspired the questions: Are female college students influenced in a positive way by female science teaching assistants (TAs), and if so how can their influence be measured? The study tested the hypothesis that female TAs act as role models for female students and thereby encourage interest and increase overall performance. To test this "role model" hypothesis, the reasoning ability and self-efficacy of a sample of 724 introductory college biology students were assessed at the beginning and end of the Spring 2010 semester. Achievement was measured by exams and course work. Performance of four randomly formed groups was compared: 1) female students with female TAs, 2) male students with female TAs, 3) female students with male TAs, and 4) male students with male TAs. Based on the role model hypothesis, female students with female TAs were predicted to perform better than female students with male TAs. However, group comparisons revealed similar performances across all four groups in achievement, reasoning ability and self-efficacy. The slight differences found between the four groups in student exam and coursework scores were not statistically significant. Therefore, the results did not support the role model hypothesis. Given that both lecture professors in the present study were males, and given that professors typically have more teaching experience, finer skills and knowledge of subject matter than do TAs, a future study that includes both female science professors and female TAs, may be more likely to find support for the hypothesis.
ContributorsEbert, Darilyn (Author) / Lawson, Anton (Thesis advisor) / Maienschein, Jane (Committee member) / Mustard, Julie (Committee member) / Arizona State University (Publisher)
Created2010
Description
The assessment and evaluation of dietary intake and nutrition knowledge in female athletes is especially important due to the high prevalence of inadequate intake in this population (Black et al., 2019). This study evaluated 1) the relationship of nutrition knowledge and dietary intake among collegiate female athletes at the National Collegiate Athletic Association (NCAA) Division I, National Junior College Athletic Association (NJCAA), and Club sport levels and 2) the impact of competition level on this relationship as well. Participants (NCAA DI, n=51; NJCAA, n = 36; Club, n = 37) in this study answered two questionnaires, the Nutrition Sport Knowledge Questionnaire (NSKQ) and the Rapid Eating Assessment for Participants (REAP) questionnaire to assess knowledge and dietary intake. Participants also provided anthropometric and demographic information. The NSKQ was scored as a whole and for each of the four subcategories. REAP was scored both by tallying the number of “usually/often” frequency responses and given a numeral score to estimate diet quality. Statistical analysis was conducted using Kruskal-Wallis, Chi-square and Spearman’s correlation tests to compare differences within subgroups of participants and evaluate any relationships that may exist between nutrition knowledge and dietary intake with significance set at p≤0.05. Differences in nutrition knowledge between competition groups were significant, H(2)= 16.94, p< 0.001. NCAA DI (p<0.001) and Club (p<0.001) athletes had higher nutrition knowledge than athletes at the NJCAA level. This was true for overall knowledge as well as knowledge subcategories. However, minimal relationships between nutrition knowledge and dietary intake were found. The overall correlation value was rs(118)= -0.10 (95%CI: -0.28 to 0.08), p>0.05. This suggests those with higher nutrition knowledge did not necessarily have better dietary intake. Improvements in the assessment of nutrition knowledge and quick assessment of dietary quality and the relation between both is needed.
ContributorsSkinner, Jensen Drew (Author) / Wardenaar, Floris (Thesis advisor) / Johnston, Carol (Committee member) / Yudell, Amber (Committee member) / Arizona State University (Publisher)
Created2020