Although it has been shown that clean perforation tunnels facilitate the evolution of a single, deeper-penetrating wormhole, there are no reported applications of reactive shaped charges in carbonates prior to acid stimulation. The present study was instigated to evaluate the impact of reactive charges on acid wormholing in representative carbonate cores. A set of oil-saturated Indiana limestone and cream chalk cores have been perforated under simulated downhole conditions using either a conventional or a reactive shaped charge of equal explosive load. After CT scanning to eliminate outlying perforations affected by rock property anomalies, the set of cores were subjected to identical acid injection treatments representative of typical carbonate reservoir stimulations. Time to breakthrough and effluent chemistry were both analyzed and recorded. Finally, post-stimulation CT scans were used to evaluate wormhole morphology. The laboratory experiments showed that reactive charges provide wider perforation tunnels with higher injectivity, which is beneficial for any type of stimulation job. Higher injectivity tunnels help to propagate more dominant and straighter wormholes resulting in less acid to break through the cores. This technology has a significant potential when perforating tight formations or heterogeneous intervals, where obtaining clean tunnels with conventional perforators is most challenging. Further research work needs to be done to evaluate if the difference in acid volume to breakthrough observed in the experiments would have a major impact in the field.

Thesis (M. Sc.)--University of Hong Kong, 2000. / Includes bibliographical references.

The objective of this dissertation is to evaluate how regulatory and market factors affect title insurance charges in different states. As substantial components of home purchase closing costs, title insurance charges have been controversial for decades, and both practitioners and analysts have pointed out apparent variations in title insurance charges among states. Although existing studies have suggested a set of regulatory and market factors as explanations for these among-state variations, empirical evaluations are limited. To fill in this gap, this dissertation empirically assesses whether these factors influence title insurance charges. The research outcomes of these dissertation indicate that after taking into account market factors such as services included in title insurance charges, title-related losses, property values, state populations, home sale volumes, housing prices, and income levels, regulation styles can still partially explain the title insurance charge variations in different states. In particular, states with promulgation regulation can have a higher average title insurance charge than states allowing free competition. This dissertation also tests whether regulation affects title insurance charges by influencing competition in the market and whether regulators' characteristics are related to the effect of regulation on charges. The test results imply that appointed commissioners can be associated with a higher average title insurance charge than elected commissioners. This dissertation provides insights into the title insurance regulatory reform in different states. More broadly, one methodology (multiple model for change) used in this dissertation simultaneously assesses regulation's over-time and state-by-state effects on title insurance charges, which contributes to the development of regulation evaluation methods. The outcomes of this dissertation can also provide empirical evidence to the theoretical debate of regulation versus competition. / text

My dissertation examines theoretically the effects of environmental taxation on welfare in various cases. Using a general equilibrium model, the first chapter shows that a Pigouvian tax provides a larger welfare gain than an output tax, since it induces substitution among inputs as well as reduction in output of the dirty good, while an output tax induces only the output reduction. Using data for China and the U.S., numerical simulation results show that the potential welfare loss from not being able to use a Pigouvian tax is much larger in developing countries than in developed countries. The second chapter focuses on the fact that recycled material needs reprocessing to be substitutable for virgin material. Reprocessing uses resources and, in the process, generates pollution. Incorporating these 'imperfect' characteristics into a simple general equilibrium model, I examine how these realistic factors affect the structure of taxsubsidy schemes when the Pigouvian taxes are not available. A generalized Deposit-Refund system can achieve the optimum if illegal dumping is not taxable. Without a Pigouvian tax on illegal dumping, recycling is subsidized for its role in diverting illegal disposal into proper disposal. If Pigouvian taxes on neither illegal disposal nor waste from imperfect reprocessing are available, a combination of output tax on reprocessed material and subsidies for clean inputs can be used to restore the optimum. In the process, another reason to subsidize recycling emerges: recycling is a clean input for imperfect reprocessing. The third chapter focuses on the validity of the results obtained in the first chapter in the case of two vertically-separated oligopolies where the upstream industry is polluting. Using an analytical partial equilibrium model, I show that a tax on pollution is potentially superior to a tax on intermediate good, since the former can utilize both the upstream firms' input substitutability and the downstream firms' input substitutability, while a tax on intermediate good only utilizes the downstream firms' input substitutability. I also derive the conditions that government can improve social welfare through various revenue-neutral tax reforms.

Thesis (Ph. D.)--University of Texas at Austin, 2007. / Vita. Includes bibliographical references.

Thesis (doctoral)--Göteborgs universitet, 2003. / Extra t.p. with thesis statement inserted. Includes bibliographical references.

Thesis (M.Hous.M.)--University of Hong Kong, 2003. / Includes bibliographical references (leaves 107-108). Also available in print.

Thesis (Ph. D.)--Indiana University, 1992. / Includes bibliographical references (leaves 210-218).

Thesis (M.P.A.)--University of Hong Kong, 2005.

Thesis (M.S.)--West Virginia University, 2006. / Title from document title page. Document formatted into pages; contains viii, 104 p. : col. maps. Includes abstract. Includes bibliographical references (p. 83-88).