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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
The study of tomboys offers useful insights for the field of gender development. Tomboys have been the focus of several studies aimed at defining what a tomboy is (Bailey, Bechtold, & Berenbaum, 2002; Plumb & Cowan, 1984; Williams, Goodman, & Green, 1985) and what it means for children and adults who are tomboys (Morgan, 1998; Williams et al., 1985). These and further questions necessitate understanding the correlates and consequences for children exhibiting tomboy behaviors. This study aims to address these gaps in the literature as part of a longitudinal study assessing children's gendered attitudes, relationships, and beliefs. A group of 4th grade girls (N=98), were administered questionnaires asking them about their tomboy gender identity and related behaviors and beliefs. The first research question concerns how we identify tomboys through parent, teacher, and child self-report, and the application of groupings of tomboys as never, sometimes, and always tomboys. It was found that children who fall into different classifications of tomboyism differ on their similarity to own- and other-sex peers on a number of dimensions (e.g. similarity, peer preference, activity preference). Never tomboys had the most similarity and interest to own-sex peers, always tomboys, to other-sex peers, and sometimes tomboys exhibited the most flexibility with interest similar to both own- and other-sex peers. Peer-related adjustment consequences and experiences were considered for the different groups of tomboys, with always tomboys being the most efficacious with other-sex peers, never tomboys being the most efficacious with own-sex peers, and sometimes tomboys showing both own- and other-sex peer interactions and the least exclusion of any group.
ContributorsEngland, Dawn (Author) / Martin, Carol L (Thesis advisor) / Zosuls, Kristina (Committee member) / Updegraff, Kimberly (Committee member) / Arizona State University (Publisher)
Created2012
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
This study examines the relations among three aspects of temperament (shyness, impulsivity, and effortful control), resting respiratory sinus arrhythmia (RSA) recorded during a calming film and RSA suppression during three behavioral measures of effortful control, and adjustment (anxiety and externalizing behavior) in a sample of 101 preschool-age children. Principal components analysis was used to create composites for effortful control, shyness, impulsivity, anxiety, and externalizing behavior, and hierarchical regression analysis was used to test the study hypotheses. As expected, baseline RSA was negatively related to effortful control in shy children, but was unrelated to effortful control in children who were not shy. It was hypothesized that high baseline RSA would reduce the relation between shyness and anxiety, and between impulsivity and externalizing behavior; this hypothesis was supported for externalizing behavior, but not for anxiety. The interaction between impulsivity and RSA as a predictor of externalizing was statistically independent of effortful control, indicating that these are unique effects. Finally, it was hypothesized that RSA suppression would be positively related to effortful control for children low, but not high, in shyness. There was a marginal interaction between shyness and RSA suppression, with RSA suppression marginally negatively related to EC for children low in shyness, but unrelated to effortful control for children high in shyness; the direction of this association was opposite predictions. These findings indicate that RSA is more strongly related to effortful control for children high in shyness, and that it consequently may not be appropriate to use RSA as an index of EC for all children. This study also draws attention to the need to consider the context in which baseline RSA is measured because a true baseline may not be obtained for shy children if RSA is measured in an unfamiliar laboratory context. The finding that high RSA moderated (but did not eliminate) the relation between impulsivity and externalizing behavior is consistent with the conceptualization of RSA as a measure of self-regulation, but further research is needed to clarify the mechanism underlying this effect.
ContributorsSulik, Michael John (Author) / Eisenberg, Nancy (Thesis advisor) / Spinrad, Tracy L. (Committee member) / Lemery-Chalfant, Kathryn (Committee member) / Arizona State University (Publisher)
Created2012
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
Resettled refugees face numerous challenges including unsafe living conditions, loss of permanent shelter, adjustment to a new culture, loneliness, and separation from family, friends, and community. Of particular importance is the lack of a feeling of sense of community (SOC) within their new surroundings. SOC is not only worthwhile as an outcome of its own, but may also predict additional positive outcomes such as resilience and cultural adjustment. Literature has shown participation in sport can develop youth positively and build social skills, while studies in other regions of the world have also found a sport team setting to be a place for immigrants to experience SOC. In this study, I use a congruent mixed methods approach to both explore the experience of SOC for youth refugees in a soccer club, and examine the relation of SOC to resilience and cultural adjustment. Using photo-elicitation and semi-structured interviews with 11 youth participants, the qualitative portion of the study explored SOC among youth participants. Findings note the presence of SOC as matched to theoretical frameworks both specific to sport, and to a more general theory of SOC. Further data were collected through questionnaires distributed to club members. Results from the quantitative analysis indicate a significant positive relation between SOC and resilience, and SOC and perceived acculturation. This study’s contribution is to illustrate how refugee youth in a sport club in the United States experience SOC, and the impact of that SOC. Results suggest practical implications for sport managers who wish to provide positive sport experiences for youth refugees.
ContributorsFader, Nina (Author) / Legg, Eric (Thesis advisor) / Larsen, Dale (Committee member) / Klimek, Barbara (Committee member) / Arizona State University (Publisher)
Created2018
Description
The goal of this study was to explore the multidimensionality of gender typicality and its relation to preadolescents’ psychological adjustment. With a sample of 378 6th grade students (52% male; M age = 11.44, SD = .56; 48% White), I examined how four specific dimensions of gender typicality (behavior, appearance, activities, and peer preference) predict children’s global sense of typicality; whether children’s global sense of gender typicality, behavior, appearance, activities, and peer preference are differentially predictive of self-esteem, social preference, and relationship efficacy; and whether examining typicality of the other gender is important to add to own-gender typicality. Regression analyses indicated that all four specific typicality dimensions contributed to preadolescents’ overall sense of own- and other-gender typicality (except appearance for own-gender typicality). Generally, all domains of gender typicality were related to the four adjustment outcomes. Own-gender typicality related more strongly to self-esteem, social preference, and own-gender relationship efficacy than did other-gender typicality; other-gender typicality was more strongly related to other-gender relationship efficacy. Relations between typicality and adjustment were stronger for gender-based relationship efficacy than for self-esteem or social preference. Although some differences existed, relations between typicality and adjustment were generally similar across typicality domains. Results implicate the need to measure other-gender typicality in addition to own-gender typicality. Additional contributions and suggestions for future research are discussed.
ContributorsCook, Rachel (Author) / Martin, Carol L (Thesis advisor) / Updegraff, Kimberly A (Committee member) / Miller, Cindy F (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