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The tomographic reconstruction of hypersonic flows faces two challenges. Firstly, techniques used in the past, such as the Direct Fourier Method (DFM) or various backprojection techniques, have only been able to reconstruct areas of the flow which are upstream of any opaque objects, such as a model. Secondly, shock waves create sharp discontinuities in flow properties, which can be difficult to reconstruct both in position and in magnitude. This thesis will present a reconstruction method, utilising geometric ray-tracing and a sparse matrix iterative solver, which is capable of overcoming both of these challenges. It will be shown, through testing with phantom objects described in imaging and tomographic literature, that the results are comparable to those produced by the DFM technique. Finally, the method will be used to reconstruct three dimensional density fields from interferometric shock tunnel images, with good resolution.

The character of the primary seismic wave in the range of distances between 100 and 600 km is affected by such factors as the nature of the source, exponential attenuation, crustal structure, type of wave propagation, recording site geology and instrument response. The first arrivals from the GNOME and SHOAL nuclear explosions were analyzed to show the important effects of the above factors. Crusta1 structures were developed to examine the type of wave propagation, geometrical attenuation, and Q versus depth structure. Within the frequency bands delineated by the instrument response, above 2 cps, and the reliable source energies, exponential attenuation and surface geology explained the major spectral variations in the first arrivals. Amplitude variations were explained almost entirely by geometrical and exponential attenuation. Techniques for measuring exponential attenuation were developed and applied. The Q values obtained were primarily between 100 and 200. / Graduation date: 1968

Thesis (M. Phil.)--University of Hong Kong, 2006. / Title proper from title frame. Also available in printed format.

The gastrointestinal epithelium normally sealed by tight junctions, which act as a structural barrier and paracellular channels. Inflammation can increase the permeability of microvasculature that result in plasma leakage. Mammalian intestinal epithelium has many goblet cells which discharge mucus in the inflammatory response. The discharging mucus functioning is as a defensive barrier and lubricant. The mucus layer is the anatomical site at which the host first encounters gut bacteria, physical damage, and chemical stimulant. The heat shock response is one of the most primitive cellular defense mechanism. A variety of stressful situations including environmental (ultraviolet radiation or heavy metals), pathological (infections or malignancies), or physiological (growth factors) stimuli induce heat shock proteins. This study investigated the effect of heat shock on endotoxin-induced plasma leakage and goblet cell mucus discharge in the small intestine of rats of Sprague-Dawley (SD) and Long-Evans (LE) strains. India ink was used as the tracer to detect leaky microvessels. The mucus secretion of the goblet cells of intestinal villi was observed with scanning electron microscopy and calculated with digital morphomertric software SimplePCI. Our results showed that endotoxin-induced plasma leakage and goblet cell discharging in the two strains increased significantly as compared to rat groups receiving saline. Numerous openings on the epithelial surface of villi resulted from compound exocytosis of mucus granules in goblet cells. Either 30 min or 1h after LPS injection, heat shock pretreatment in LE rats LPS-induced plasma leakage in the duodenum and ileum was reduced by 58-80% (P<0.01). 1 h after LPS injection in LE rats pretreated with heat shock, the number of discharging goblet cells in the ileum was reduced (P<0.05). In SD rats, heat shock inhibited LPS-induced plasma leakage in the duodenum and ileum at 1h after LPS injection by 56-68% (P<0.01), and the number of discharging goblet cells was reduced in the duodenum and ileum (P<0.05). In conclusion, heat shock could protect rat intestine from endotoxin-induced inflammation and mucus secretion.

This thesis describes the implementation of a parametric model of an automotive damper. The goal of this research was to create a damper model to predict accurately damping forces to be used as a design tool for the Formula SAE racecar team. This study pertains to monotube gas charged dampers appropriate to Formula SAE racecar applications. The model accounts for each individual flow path in the damper, and employs a flow resistance model for each flow path. The deflection of the shim stack was calculated from a force balance and linked to the flow resistance. These equations yield a system of nonlinear equations that was solved using Newton's iterative method. The goal of this model was to create accurately force vs. velocity and force vs. displacement plots for examination. A shock dynamometer was used to correlate the model to real damper data for verification of accuracy. With a working model, components including the bleed orifice, piston orifice, and compression and rebound shims which were varied to gain an understanding of effects on the damping force.

Thesis (doctoral)--Cranfield Institute of Technology, 1991. / BLDSC reference no.: DX94724.

Thesis (M.S. in Mechanical Engineering)--Naval Postgraduate School, December 2009. / Thesis Advisor(s): Hixson, Robert S. Second Reader: McNelley, Terry. "December 2009." Description based on title screen as viewed on January 27, 2010. Author(s) subject terms: Porous foams, dynamic compaction, multi-layered armor, ballistic performance, shock wave attenuation. Includes bibliographical references (p. 89-90). Also available in print.

Thesis--University of Florida. / Manuscript copy. Description based on print version record. Vita. Bibliography: leaves 79-80.

Thesis (Ph. D.)--University of Texas at Austin, 2003. / Vita. Includes bibliographical references. Available also from UMI Company.