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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
In 2009, cap and trade was at the forefront of political and environmental discussions. At this time, the American Clean Energy and Security Act passed in the United States House of Representatives. Market based systems are alternatives to traditional regulatory methods such as command and control. This study intended to assess the attitudes of environmental leaders who managed air emissions as a part of their job responsibilities. The attitude of these individuals would have influenced their acceptance of this method as a program to reduce environmental pollution and improve air quality. The purpose of this study was to evaluate the attitudes of South Carolinian Title V environmental leaders toward cap and trade. Additionally, the study intended to determine if experience impacted the attitudes of survey respondents. Lastly, the study determined if environmental leaders found current methods such as command and control effective in air pollution regulation. The survey used the Likert Method of Summated Ratings. Environmental leaders reviewed attitudinal statements about the various subjects. The leaders selected an agreement level which determined their attitudes toward the statement. Numerical response ratings evaluated the leader's attitude by experience level. The survey found that respondents had negative attitudes toward cap and trade. The respondents had a positive attitude toward traditional regulatory methods such as command and control. Lastly, the results concluded that environmental experience did not have an impact on the respondents' attitude toward cap and trade. Therefore, it can be concluded that the environmental leaders prefer traditional air pollution regulatory methods in comparison to alternatives such as cap and trade.
ContributorsLyons, Tiffiny (Author) / Olson, Larry (Thesis advisor) / Brown, Albert (Committee member) / Peterson, Danny (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
The following research is a regulatory and emissions analysis of collocated sources of air pollution as they relate to the definition of "major, stationary, sources", if their emissions were amalgamated. The emitting sources chosen for this study are seven facilities located in a single, aggregate mining pit, along the Aqua Fria riverbed in Sun City, Arizona. The sources in question consist of Rock Crushing and Screening plants, Hot Mix Asphalt plants, and Concrete Batch plants. Generally, individual facilities with emissions of a criteria air pollutant over 100 tons per year or 70 tons per year for PM10 in the Maricopa County non-attainment area would be required to operate under a different permitting regime than those with emissions less than stated above. In addition, facility's that emit over 25 tons per year or 150 pounds per hour of NOx would trigger Maricopa County Best Available Control Technology (BACT) and would be required to install more stringent pollution controls. However, in order to circumvent the more stringent permitting requirements, some facilities have "collocated" in order to escape having their emissions calculated as single source, while operating as a single, production entity. The results of this study indicate that the sources analyzed do not collectively emit major source levels of emissions; however, they do trigger year and daily BACT for NOx. It was also discovered that lack of grid power contributes to the use of generators, which is the main source of emissions. Therefore, if grid electricity was introduced in outlying areas of Maricopa County, facilities could significantly reduce the use of generator power; thereby, reducing pollutants associated with generator use.
ContributorsFranquist, Timothy S (Author) / Olson, Larry (Thesis advisor) / Hild, Nicholas (Committee member) / Brown, Albert (Committee member) / Arizona State University (Publisher)
Created2011
Description
ABSTRACT In recent years, the total amount of air pollutant emissions in China was reduced year by year, but pollution is still very serious, especially in some big cities where the environmental pollution has worsened in the last 20 years. The "Law of the People's Republic of China on the Prevention and Control of Atmospheric Pollution" ( LPCAP) was established in 1987. With the development of industrialization and air pollution changes, it had been revised twice in 1995 and 2000.The third revision of the law began in 2009 which was included in the "Eleventh five-year National People's Congress Standing legislative plan" and the State Council's 2009 legislative program. At present, the third revision of the LPCAP is in progress and MEP has completed the manuscript of the revised draft of the law. The purpose of this study is to explore the current situation of China's air pollution, as well as history of LPCAP, analysis of amendments in atmospheric legislation and the achievements of the LPCAP. Combined with China current situation, the research exposed some urgent problems of the Chinese atmospheric legislation which are related to: fã The issues of the regional Total Emission Control (TEC) policy and division. fã The issues of allocation of pollutant emission allowances and trade policy fã The issues of improving the pollution emission permit system. fã The issues of the mobile source emissions management. fã The issues of fuel management. fã The issues of the guarantee measures of the implementation of the LPCAP. In addition, the study compares the LPCAP with the U.S. CAA to offer some solutions for the third revised law and tries to find a fundamental solution for the flaws of China's existing Atmospheric Pollution Prevention legal system to be more Operable. As a result, the gap in air quality in China and the developed countries of the world will be narrowed and China will be better positioned for sustainable development.
ContributorsLi, Shengtang (Author) / Olson, Larry (Thesis advisor) / Brown, Albert (Committee member) / Peterson, Danny (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
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