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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Representations of SL(2,q)

Uchtman, Christopher Lee 22 July 2015 (has links)
No description available.
112

Predicting the Dynamics of Injection-Induced Earthquakes

Schlosser, Charles Stewart 24 May 2023 (has links)
Human activities associated with the injection of fluids at depth are known to trigger earthquakes. Fluid injection increases the internal pore pressure of the host rock, which in turn reduces the effective stress and frictional resistance of faults that maintain the fractured rock system in a state of mechanical equilibrium. Under certain conditions, sufficiently high pore pressure can lower this frictional resistance below a critical threshold and initiate an earthquake – the relative motion of rock on either side of the fault plane. Many of these earthquakes are small and imperceptible without the aid of specialized instruments, but some may be large enough to pose a significant risk to life and property. Several emerging technologies that have the potential to shape the future of low-carbon energy production, including carbon capture and storage and enhanced geothermal energy production, are inextricably linked to large-scale injection of fluids into the subsurface. The risk of injection-induced earthquakes is a primary concern and potential barrier to widespread adoption of these technologies. New tools are required to help operators manage these risks and meet stakeholder expectations. Current knowledge enables operators to predict the conditions that would trigger such an earthquake, but few or no tools exist to predict the severity of the earthquakes, precluding a complete description of the risk associated with operating a large-scale injection well. This dissertation details the theoretical justification and initial validation of a methodology and software to simulate the motion of an earthquake as it occurs and quantify the severity in terms that are germane to experts in earthquake science. Specifically, this work utilizes the finite element method to solve the equations of motion dictated by the three-dimensional linear elastic constitutive equation. Novel aspects of this research include the treatment of friction at the fault interface as a constraint on the motion of the system, and the numerical methods necessary to solve this problem. This software was created exclusively with free and open source software, so that every aspect of its internal machinery may be scrutinized, replicated, and improved by future workers. / Doctor of Philosophy / Human activities associated with the injection of fluids at depth are known to trigger earthquakes. Many of these earthquakes are small and imperceptible without the aid of specialized instruments, but some may be large enough to pose a significant risk to life and property. Several emerging technologies that have the potential to shape the future of low-carbon energy production, including carbon capture and storage and enhanced geothermal energy production, are inextricably linked to large-scale injection of fluids into the subsurface. The risk of injection-induced earthquakes is a primary concern and potential barrier to widespread adoption of these technologies. New tools are required to help operators manage these risks and meet stakeholder expectations. Current knowledge enables operators to predict the conditions that would trigger such an earthquake, but few or no tools exist to predict the severity of the earthquakes, precluding a complete description of the risk associated with operating a large-scale injection well. This dissertation details the theoretical justification and initial validation of a methodology and software to simulate the motion of an earthquake as it occurs and quantify the severity in terms that are germane to experts in earthquake science. This software was created exclusively with free and open source software, so that every aspect of its internal machinery may be scrutinized, replicated, and improved by future workers.
113

Noise-induced hearing loss : conservation and effects /

Cheung, Mei-chi, Dilys. January 1995 (has links)
Thesis (M. Sc.)--University of Hong Kong, 1995. / Includes bibliographical references (leaves 72-75).
114

Mass Spectrometry: Toward Elucidating the Biosignature of Coccidioidomycosis and Insights into Surface Induced Dissociation of Biologically Relevant Carbohydrates

VanSchoiack, Andrew D. January 2015 (has links)
Mass spectrometry (MS) has proven itself to be indispensable for the analysis of biomolecules and molecular systems. This research has three goals: (1) expand on prior work toward the discovery of novel diagnostic targets for Valley Fever, (2) evaluate current mass spectrometry based proteomics for the discovery of non-host protein in complex host biological samples, and (3) investigate the potential for two gas phase techniques, surface induced dissociation, and ion mobility for the analysis of carbohydrate based molecules. Mass spectrometry has allowed for great advances in the identification of proteins in biological samples through implementing liquid chromatography tandem mass spectrometry and bioinformatics techniques known as proteomics. Proteomics techniques were used to elucidate a portion of the biosignature of Valley Fever (VF), a disease of great importance in the arid regions of the western United States. Current diagnostics for this fungal lung disease are remarkably unreliable which creates a need for an unfailing diagnostic method. Using a new generation of instrumentation along with directed methods, four previously discovered VF marker proteins were evaluated for their presence in mouse plasma, lung homogenate and bronchoalveolar lavage fluid samples. Due to inconclusive data, discovery proteomics approaches were then used to identify possible diagnostic targets in both human and mouse bronchoalveolar lavage fluid. In human bronchoalveolar lavage fluid, one potential target was discovered in five out of eight VF positive samples, and two further identifications of VF in negative samples. Mouse bronchoalveolar lavage fluid also showed the presence of this protein. Multiple-reaction monitoring based validation, using two-dimensional online separations for the presence of either the newly discovered protein or the four previously discovered proteins, was inconclusive. Emerging from the difficulties observed by the author and colleagues in identifying infectious agent proteins in complex host biological samples, an investigation of the feasibility of undertaking such endeavors was performed. One of the main complications thwarting the discovery of infectious agent proteins is the dynamic range of protein concentration in the host biological sample. This issue was resolved by using commercially available mass spectrometry and a two-dimensional liquid chromatographic separations platform. This enhanced separation combined with cost-effective protein normalization techniques, identified non-host proteins with good sequence coverage and spectral counts. Combining antibody-based depletion of highly abundant plasma proteins in bronchoalveolar lavage fluid, with at least a three fraction sample analysis enabled detection of a low abundant non-host protein (2pmol in 50μg host protein) with high sequence coverage. Glycosylation, an abundant post-translational modification of protein composed of carbohydrate oligomers may hold within its structure more biologically relevant information than the DNA that encoded the protein on which the glycan resides. The analysis of glycosylation plays a critical role in understanding biology. Carbohydrate based moieties pose many distinct challenges to their analysis; two of which are isobaric fundamental units and complex branching chemistry. Mass spectrometry provides a way of overcoming some of these challenges. To examine the complex biomolecules, a gas phase ion separation technique, known as ion mobility, and a non-traditional ion activation technique, surface-induced dissociation, were used. Surface-induced dissociation provides analogous fragmentation patterns to those generated via collision-induced dissociation (CID); however, much more extensive fragmentation can be achieved in a single tandem MS experiment. Using the gas-phase separations power of ion mobility showed that multiple conformations were adopted by relatively simple oligosaccharides. Ion mobility was also successfully used to determine fragment ion lineage of isobaric fragment ions, through inline separation between two differential fragmentation experiments.
115

Immunomodulation of autoimmune disease using peptides derived from heat shock proteins

Francis, James Nicholas January 1999 (has links)
No description available.
116

The natural history of immune responses to malaria

Kinyanjui, Samson Muchina January 2001 (has links)
No description available.
117

Near-infrared absorption by atmospheric gases

Chagas, Julio C. S. January 2001 (has links)
No description available.
118

The role of human alpha-2-macroglobulin in health and disease

Senthilmohan, Tharmalingam January 1994 (has links)
No description available.
119

Deep level transient spectroscopy studies of various silicon substrates

Ahmed, Mahfuza January 1998 (has links)
No description available.
120

A study of the electrical properties of point and extended defects in silicon

Amaku, Afi January 1997 (has links)
No description available.

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