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- Genre: Masters Thesis
- Creators: Arizona State University
- Creators: Chakraborty, Bijeta
- Member of: ASU Electronic Theses and Dissertations
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 thesis explores the ways two contemporary artists engage the archive to challenge ideas calcified through visual culture. Steven Yazzie and Lorna Simpson respond to constructions of history through art making strategies and practices. Yazzie's photogravure Tsosido Sweep Dancer (2009) presents a carefully constructed image of a ceremony drawing on symbols of Indianness to provoke a critical dialogue that questions the role of the American Indian stereotype in the United States imaginary. Simpson's Counting (1991) is a multilayered work that juxtaposes text and image to address the capriciousness of memory, power and other issues found at the intersection of race and gender. These photography-based works draw on the histories of ethnographic and criminal photography to deconstruct the same knowledge that photography helped to construct. Throughout the thesis I examine the relationship of the photographic archive to colonial histories by considering whose history is represented through photography. These thoughtful and challenging artworks contribute to a growing body of work that proposes new narratives drawing on embodied knowledge and experience to create a counter-archive.
ContributorsWaitoller, Lekha Hileman (Author) / Malagamba-Ansótegui, Amelia (Thesis advisor) / Lineberry, Heather S (Committee member) / Mesch, Ulrike C (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
Art and law have a troubled relationship that is defined by steep hierarchies placing art subject to law. But beyond the interplay of transgressions and regulations, manifest in a number of high-profile cases, there are more intricate connections between the two disciplines. By expanding the notion of law into the concept of a hybrid collectif of legality, the hierarchies flatten and unfamiliar forms of possible interactions emerge. Legality, the quality of something being legal, serves as a model to show the capricious workings of law outside of its own profession. New juridical actors—such as algorithms—already challenge traditional regulatory powers and art could assume a similar role. This thesis offers a point of departure for the involvement of art in shaping emergent legalities that transcend existent jurisdictions through computer code.
ContributorsSchreiber, Christoph (Author) / Hoy, Meredith (Thesis advisor) / Codell, Julie F. (Committee member) / Afanador-Pujol, Angélica J. (Committee member) / Arizona State University (Publisher)
Created2018
Description
Shirin Neshat is recognized as the most prominent artist of the Iranian diaspora. Her two photographic series, Women of Allah (1993-97) and The Book of Kings (2012), are both reactions to the socio-political events and the change of female identity in Iran. The search for Iranian identity has a long tradition in Iranian photography. Neshat's figures, with their penetrating gazes, heavy draperies, and body postures, make reference to nineteenth-century Qajar photography. Through various cultural elements in her artworks, Neshat critiques oppression in Iranian society. Neshat employs and inscribes Persian poetry to communicate contradiction within Iranian culture.
To read Neshat’s photography, it is crucial to register her use of Persian language and historical poetry. Although the reading and understanding of the Persian texts Neshat inscribes on her photographs plays a fundamental role in the interpretation of her work, Neshat’s artworks are not entirely conceptual. The lack of translation of these included texts in Neshat’s exhibitions indicates a decorative use of Persian calligraphy. The Western eye can aesthetically explore this exotic Eastern decorative calligraphy. The formal qualities of Neshat’s photographs remain, even if the viewer is unable to read or understand the Persian texts.
To read Neshat’s photography, it is crucial to register her use of Persian language and historical poetry. Although the reading and understanding of the Persian texts Neshat inscribes on her photographs plays a fundamental role in the interpretation of her work, Neshat’s artworks are not entirely conceptual. The lack of translation of these included texts in Neshat’s exhibitions indicates a decorative use of Persian calligraphy. The Western eye can aesthetically explore this exotic Eastern decorative calligraphy. The formal qualities of Neshat’s photographs remain, even if the viewer is unable to read or understand the Persian texts.
ContributorsBokharachi, Elnaz (Author) / Mesch, Claudia (Thesis advisor) / Hoy, Meredith (Committee member) / Anand, Julie (Committee member) / Ghanem, Carla (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
Effective Altruism (EA), a moral philosophy concerned with accomplishing the greatest possible good in one’s lifetime, sees little utilitarian and/or humanitarian value in the arts. EA suggests that amidst so much global strife, the time, energy, and finances expended to create fleeting art would be put to better, more practical use in the fight against poverty. However, EA has yet to sufficiently account for sustainable art practice — an art form deeply rooted in utilitarianism and humanitarianism — and the possibility of its accompanying aesthetics as a constituent of utilitarian/humanitarian theories. The first chapter of this thesis illustrates an intersection of EA, sustainability, and aesthetics, detailing ways in which sustainable art and EA philosophy overlap, as well as problematizing EA’s dismissal of contemporary art practice. This chapter also points to sustainable art as one possible alternative art route for practicing artists with EA interests. Chapters two and three present case studies of Danish art collective SUPERFLEX and an American non-profit called the Land Art Generator Initiative (LAGI) and how their sustainable goals fit the utilitarian and humanitarian scope through which EA functions.
ContributorsNemelka, Kevin (Author) / Hoy, Meredith (Thesis advisor) / Mesch, Claudia (Committee member) / Sweeney, Gray (Committee member) / Arizona State University (Publisher)
Created2017
Description
This thesis expands the scope of literature surrounding the work of Juno Calypso, Christina Quarles, and Lisa Yuskavage by increasing the scope of their theoretical interpretations. Juno Calypso’s case requires establishing a critical foundation for her interrogations of domestic space, her subversions of feminine performance—particularly through accusatory address of the gaze—and her demonstrations of the new-hysterical process that I argue for via her alter-ego, “Joyce.” Similarly, I emphasize Christina Quarles’ subversions of art historical traditions, such as the gaze, meta-framing, and figural language, instead of her explorations into race and linguistic titular play. Finally, Lisa Yuskavage’s inclusion will bring discussions of her contemporary artworks fully into the present, leaving behind the scandalous-or-not questions plaguing her oeuvre in favor of contemporary figural reinterpretation. Through comparisons of each one’s approach to contemporary, artistic feminist theories and dilemmas, the artists convey informative insights into today’s visual culture. The thesis brings these ruminations to light through study of Calypso’s, Quarles’, and Yuskavage’s shared themes and characteristics, including subconsciously-influenced practices, multiplicity, and uncanny space. I account for one of Calypso’s most crucial yet divergent strategies of spatial uncanniness—gendered space. Calypso, Quarles, and Yuskavage are also linked by their ostensibly domestic spaces and featuring feminized figures. Yuskavage uses hyperfeminine performance as means of questioning the conventional and the pleasure one expected to receive from it; Quarles instead uses ambiguity to challenge the traditional white femininity assigned to subjecthood in order to reinforce her dissolution of race and gender. Unanswered performance and gaze questions of femininity, feminine performance and feminine rituals drive Calypso’s photographs, in which an onlooker’s voyeurism is highlighted by their mid-procedure state. Yuskavage uses the home as extension of cheesy self, a site of performance, but Quarles uses domestic spaces as sites or causes of internal struggle. Calypso is closer aligned to Yuskavage’s intersectional-feminist anxieties than Quarles’ post-pandemic ones. The temporal span of the artworks’ creation (2015-2022) is reflective of the dramatic social paradigm shifts experienced by Western societies post-BLM and other social movements, and post-COVID pandemic; the arguments made by this essay will contribute to the understanding of ongoing change experienced by women.
ContributorsBugno, Celia (Author) / Fahlman, Betsy (Thesis advisor) / Anderson, Lisa (Committee member) / Hoy, Meredith (Committee member) / Arizona State University (Publisher)
Created2023
Description
The relationship between Chinese modern and contemporary artistic creation and the national sovereignty of China is a worthy subject of debate. Within it, modernism and intellectual/artistic subjectivity are two necessary starting points. However, there is still a good deal of uncertainty around these two points. First, can the modernization process of China be accepted as the general meaning of modernization? Second, are some Chinese modern and contemporary artists actually modern intellectuals? Based on clarification of the above two uncertainties, this thesis is an attempt to argue that the Chinese artists who regard themselves, their artworks and creations, as intellectual, reflect the collision domain between themselves and the political entity of national sovereignty in China: the communist regime controlled by the CCP, Chinese Communist Party中國共産黨.
In this thesis, three chapters discuss the relationship between Chinese modern and contemporary art and the CCP. In my theoretical exposition, I argue that the artistic/intellectual subjectivity of modern Chinese artists gradually developed and changed during the conflict and struggle with the Communist rule.
In the first chapter, I introduce the biography and artistic creation of Chinese literati painters under the communist rule, exemplified by Wu Hufan吳湖帆. I analyze and demonstrate how the subjectivity of the traditional literati gradually lost strength under the pressure of nationalism, the disenchantment with modernization, and communism. In the second chapter, I focus on the Scar Art art movement of the 1970s to the 1980s, as well as representative artists and their works in this direction of art, such as Cheng Conglin程叢林 and Gao Xiaohua高小華. In this chapter, I use feminism and Foucault's political-philosophical theories to explain these visual expressions of the memory of historical trauma in Scar Art during this period. In Chapter 3, by discussing the works of two artists, He Gong何工 and Ai Weiwei艾未未, in the context of Foucault’s political philosophy, I argue that artists how to express their intellectual subjectivity and political resistance through their contributions to Chinese contemporary art.
In this thesis, three chapters discuss the relationship between Chinese modern and contemporary art and the CCP. In my theoretical exposition, I argue that the artistic/intellectual subjectivity of modern Chinese artists gradually developed and changed during the conflict and struggle with the Communist rule.
In the first chapter, I introduce the biography and artistic creation of Chinese literati painters under the communist rule, exemplified by Wu Hufan吳湖帆. I analyze and demonstrate how the subjectivity of the traditional literati gradually lost strength under the pressure of nationalism, the disenchantment with modernization, and communism. In the second chapter, I focus on the Scar Art art movement of the 1970s to the 1980s, as well as representative artists and their works in this direction of art, such as Cheng Conglin程叢林 and Gao Xiaohua高小華. In this chapter, I use feminism and Foucault's political-philosophical theories to explain these visual expressions of the memory of historical trauma in Scar Art during this period. In Chapter 3, by discussing the works of two artists, He Gong何工 and Ai Weiwei艾未未, in the context of Foucault’s political philosophy, I argue that artists how to express their intellectual subjectivity and political resistance through their contributions to Chinese contemporary art.
ContributorsSun, Yiliang (Author) / Mesch, Ulrike (Thesis advisor) / Brown, Claudia (Committee member) / Baker, Janet (Committee member) / Arizona State University (Publisher)
Created2020
Description
Many contemporary artists have turned to the past in order to negotiate and make sense of their relationship with the present. Similarly, museums have begun to look back in order to push forward and through a revisionist lens they scrutinize their collections and reveal ignored object histories. A prominent method some museums implement is allowing contemporary artists to comb through the vaults and present new relationships between their objects to their visitors. Through a psychological analysis of memory, and theorists’ dissection of nostalgia, object agency, and contemporaneity, I argue that artists Spencer Finch, Do Ho Suh, Newsha Tavakolian, Solmaz Daryani, Malekeh Nayiny, Mitra Tabrizian, Mark Dion, Fred Wilson, and Gala Porras-Kim function as revivalists – or artists whose works use memory and nostalgia to bring the past back to life. By attempting to retrieve memories, create nostalgic experiences, and question histories, they make their works tools for remembrance, reconciliation, and renegotiation with the past and present. The concerns these artists bring to the surface through their works build an understanding of how memory and nostalgia function as devices for personal meaning-making, trauma processing, and human-object relationship building.
ContributorsZiesmann, Hannah Grace (Author) / Fahlman, Betsy (Thesis advisor) / Codell, Julie (Committee member) / Lineberry, Heather (Committee member) / Arizona State University (Publisher)
Created2020