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The process of fracture propagation driven by the pressure of the fluid flow between the fracture surfaces has been of considerable interest for understanding natural geological phenomena such as the formation of volcanic dikes and developing hydraulic fracturing technologies for industrial applications. Man-made hydraulic fracturing has been most commonly used for stimulation of oil and gas reservoirs to increase hydrocarbon production, stimulation of geothermal reservoirs, remediation of soil and groundwater aquifers, injection of wastes, goafing and fault reactivation in mining, and measurement of underground in situ stresses.Computational modeling and simulation of fluid driven fracture propagation in realistic geological formation has been a challenging problem because of various complexities including formation heterogeneities and the use of highly nonlinear engineered fluids. At present, one of the main obstacles for the robust industrial application of the simulating technology is the computational efficiency and stability. The objective of this study is to investigate the numerical efficiency and stability of various algorithms that can be potentially used in modeling of fluid driven fracture propagation. For simplicity, we have focused on fracture propagation in the plane strain condition. The fracture is assumed to in homogeneous linearelastic medium and modeled using displacement discontinuity boundary element method (DDBEM). The nonlinear power-law fluid flow is modeled using conventional lubrication theory. The coupled equations are then discretized using zero order elements for its efficiency. The coupled equations become increasingly stiff and difficulty to solve when the power law indices become smaller. Various numerical algorithms such as Newton iterationwith line search, trust-region and quasi-Newton method are investigated and compared. We have also extended the model to the fluid driven non-planar fracture propagation. A numerical crack propagation criterion based on the minimum local shear stress under mixed loading condition is proposed and compared with conventional theoretical and numerical criteria. The new crack propagation criterion provides more accurate and smooth crack initiation paths. Finally we have studied the geomechanics interaction between two simultaneous fluid driven fractures. The results provided some useful inputs for optimal design of multiple stage and multiple fracturing treatments along horizontal wells currently adoptedby the oil and gas industry for the economical recovery of unconventional resources such as shale gas and oil.

Abstract: The TV show is a central focus of American life, one that not only reflects but also produces social imaginaries for the American audience that support the way people interact and engage with reality. It is the nation’s most influential storyteller, which dominates the nation’s imagination and understanding of reality. This dissertation explores the political and cultural meanings of four TV shows from the George W. Bush era: The West Wing (1999-2007), Deadwood (2004-06), The Wire (2002-08) and Heroes (2006-10). In examining these TV shows, this dissertation aims to shed light on both the origins of the state of exception, its conduct, its purpose, and the possibility of meaningful critique of or resistance to the state of exception. Chapter I discusses The West Wing, focusing on President Bartlet’s decision-making process regarding the assassination of Abdul Shareef, so as to elucidate the decisive actions of a sovereign figure in a state of exception. Chapter II explores Deadwood’s resurrection of the nineteenth-century mining camp in our twenty-first century, in terms of the capitalist state of exception. In discussing the show’s portrayal of the conflicts among the main characters, this chapter reveals that the same sovereign logic of exception is innate in the expansion of capitalism. Chapter III examines The Wire’s depiction of rebellious petty-sovereigns such as Major Colvin, Detectives McNulty and Freamon. According to The Wire, the claims of equality are deeply urgent in the bleak reality of contemporary America. With their commitment to equality and justice, the petty-sovereigns intervene in the bleak reality in their subversive ways. Chapter IV explores Heroes’s rendering of the main characters’ struggles against a fictional national emergency, the Company’s conspiracy to blow up half of New York City. In this chapter, I argue that Heroes portrays a political subject that attempts to constitute itself outside biopolitical sovereign power—what Hardt and Negri would call the advent of the multitude. While explicating the struggles of the main characters, I argue that its limitation in envisioning a new world underscores how contemporary critics fail to see past sovereign politics when they imagine another world.