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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 purpose of this research study provided observational techniques and Applied Behavior Analysis (ABA) prompts and fading procedures to analyze music therapist-child interaction for child with autism spectrum disorder. Impaired social interaction is the primary symptom of a child with autism spectrum disorder. However, social interaction exists everywhere and throughout human life. Therefore, to improve interaction is the primary and significant goal in music therapy treatment for a child with autism spectrum disorder. The music therapist designs a series of music therapy activity interventions in order to create a therapeutic environment, based on a child's interests and favorite activities. Additionally, the music therapist utilizes the music to build the quality of relationship and interaction with child and support child practicing interaction with the therapist. Then music therapist utilizes the process of interaction to improve child's social interaction. Once the child achieves at desired behavior, he/she has ability to apply the music therapy techniques independently in the real world situations, such as family and schools that the child has learned throughout the process of interaction with therapist. The participants were three children with autism spectrum disorder and two certified music therapists (MT-BC). The researcher calculated the number of prompts and cues which the therapists provided, and the number of appropriate responses by each child in each activity intervention. Then the researcher utilized Applied Behavior Analysis (ABA), prompt and fading procedure in order to analyze the progress of therapist-child interactions during the sessions. The result showed that the children had improvement in the interactions with their therapist.
ContributorsLiao, Yin-chun (Author) / Crowe, Barbara J. (Thesis advisor) / Rio, Robin (Committee member) / Dishion, Thomas J. (Committee member) / Arizona State University (Publisher)
Created2013
Description
The purpose of this research project is to explore which musical mode, major and minor, is more effective to motivate children with Asperger's syndrome. To determine the more effective mode, the researcher has conducted experiments with seven students, two female and five male, with Asperger's syndrome on motivation for participation. Simple dance movements were used as a method of measurement for their motivation. The subjects' task was copying the researcher's simple dance with music, in major or minor mode, or with no music. There were three conditions, no music, major music, and minor music. However, the first dance of the experiments that had no music condition was not measured as it was a pre-test. All of the subjects followed the dance movements three times. The second and third dances of the experiments that were major or minor music conditions were used to determine which musical mode is more effective. To determine subjects' motivation from major and minor music, there were three areas of measurement; competency (level of execution) of movements, facial expression, and concentration on the dance for each experiment. All of the experiments were video-recorded for the evaluation. As a tool of measurement, a seven-point Likert scale was used. In addition, there were three evaluators: a professional music therapist, MT-BC; an undergraduate music therapy student at ASU; and a music education student of master's degree at ASU. In the evaluation on the measurements, the scores of the major music condition were slightly higher than the scores of the minor music condition in all three areas; competency of movements, facial expression, and concentration on the dance. However, the differences of the results in all three areas were not statistically significant.
ContributorsYun, Yeo Kwang (Author) / Crowe, Barbara (Thesis advisor) / Rio, Robin (Committee member) / Stauffer, Sandra (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
About 1 in 68 children is diagnosed with Autism Spectrum Disorder (ASD) in the United States (Centers for Disease Control and Prevention [CDC], 2015). The prevalence of ASD within the population of all people with disabilities has increased, percentage changed from 1.8% to 7.1% in ten years (NCES, 2016). Music therapy, as a therapeutic intervention, has been used for children with autism since 1940s (Reschke-Hemandez, 2011). In the past 70 years' practice, music therapy research has explored the efficacy of music therapy in improving the multiple areas of functioning affected by the symptoms of autism. However, the results are varied. The objective of this study is to investigate the efficacy of music therapy on children with autism spectrum disorder using meta-analysis as the statistical analysis methodology to synthesis the research results from all the eligible studies in the field. After a comprehensive search of the literature and screening procedure, 11 studies were finally included in the meta-analysis. The results showed a medium to large effects (d = 0.73, CI [0.43-1.03]) of music therapy interventions for children with ASD. Subgroup analysis and meta-regression analysis are conducted for further exploration within the topic.
ContributorsLi, Manjing (Author) / Rio, Robin (Thesis advisor) / Sullivan, Jill (Thesis advisor) / Eubanks, Kymla (Committee member) / Arizona State University (Publisher)
Created2016