by Cecilia Y.Y. Webb. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1988. / Bibliography :leaves 219-237.

Orientador: Joel Carlos Lastória / Banca: José Antonio Garbino / Banca: Jorge de Almeida / Resumo: Foi realizado estudo transversal, descritivo e observacional de 38 nervos ulnares de pacientes com hanseníase multibacilar, com idades entre 20 e 59 anos, com diagnóstico realizado na disciplina de dermatologia da Faculdade de Medicina de Botucatu (FMB-UNESP). Estes pacientes foram submetidos à palpação, exames de eletroneurografia e ultrassonografia dos nervos ulnares direito e esquerdo com o objetivo de estudar o comprometimento do nervo pela doença e comparar os resultados dos exames. Dos nervos estudados, nove (23,68%) não apresentaram nenhuma alteração nos resultados dos exames. Os que apresentaram alteração em um ou mais dos exames realizados, somaram 29 (76,32%). Os resultados foram comparados, e os que apresentaram alterações de normalidade em dois ou mais, foram denominados compatíveis. Houve compatibilidade de 20,68% entre clínica, eletroneurografia e ultrassonografia. Observou-se que esse fato ocorreu quando o exame ultrassonográfico mostrou valores próximos do dobro da normalidade. Não houve significância estatística entre os resultados apresentados; no entanto, deve-se considerar a correspondência entre os exames clínico, eletroneurográficos e ultrassonográficos / Abstract: A cross-sectional, descriptive, observational study of 38 ulnar nerves of multibacillary patients, aged 20 to 59 years, with diagnosis made in Dermatology course of the Faculty of Medicine of Botucatu (FMB-UNESP). These patients underwent palpation, ultrasound exams and electroneurography ulnar nerve left and right in order to study the nerve disease involvement and compare the test results. The nerves studied, nine (23.68%) showed no change in the results of the examinations. Those who had alterations in one or more of the tests performed, totaled 29 (76.32%). The results were compared, and those with normal changes in two or more, were called compatible. There was 20.68% compatibility between clinical, electroneurography and ultrasound. It was observed that this actually occurred when the ultrasound examination showed values close to double the normal. There was no statistical significance between the results presented; however, one must consider the correlation between the clinical, electroneurographic and ultrasonography / Mestre

Thesis (M.S.) -- Worcester Polytechnic Institute. / Keywords: ultrasound modeling; annular arrays. Includes bibliographical references (p.197-198).

Thesis (M. Phil.)--University of Hong Kong, 2007. / Title proper from title frame. Also available in printed format.

<p>The group for non-destructive testing at Uppsala University has recently implemented the phase shift migration method, which is a method to focus images acquired unfocused using ultrasound. However, their work has been limited to 2D data, while for many applications the gathered data is 3D. This project has extended the old implementation to 3D data. The new implementation has been done in two different ways, giving one algorithm that works fast but needs much RAM, and one algorithm that takes long time but works on smaller computers, not demanding as much memory. The fast algorithm works faster than the time it takes to acquire the raw data, which makes real-time use realistic. To test the performance of the two algorithms with respect to image improvement, both against each other and against the previous 2D implementation, a number of experiments were carried out, which showed that, apart from processing time, the two new algorithms were equal in performance. The experiments also showed that the obtained resolution in both x- and y-directions matched the theoretical discussion.</p>

Développer une méthode de caractérisation théorique complète d'un spray sur base de la connaissance du mécanisme de formation des gouttes et pouvant être appliquée de façon similaire quel que soit le type de spray, constitue l'axe central de la présente recherche. La difficulté principale étant la connaissance de la physique de rupture de la nappe liquide en gouttelettes, l'étude entreprise s'est attachée à la description du spray ultrasonique, qui a l'avantage d'impliquer un mécanisme de formation d'ondes de surface (ondes de Faraday) largement étudié. Les moyens mis en oeuvre pour trouver la loi de distribution théorique qui décrit au mieux la pulvérisation ultrasonique sont, d'un côté, l'analyse de l'instabilité des ondes de surface, qui permet de déterminer les caractéristiques moyennes du spray, et de l'autre, une méthode stochastique, le formalisme de l'entropie maximale, qui fournit la distribution la plus probable basée sur les caractéristiques moyennes et sur les lois de conservation élémentaires applicables à tout type de pulvérisation (conservation de la masse et de l'énergie). La validation expérimentale de cette nouvelle approche théorique a permis en outre de développer de nouveaux designs de pulvérisateurs performants.// To develop a method of complete theoretical characterization of a spray based on the knowledge of the of droplet formation mechanism and being able to be applied in a similar way whatever the type of spray, constitute the central axis of this research. The main difficulty being the knowledge of the physics of liquid film break-up into droplets, the study undertaken was concerned with the description of the ultrasonic spray, which has the advantage of implying a mechanism of formation of surface waves (Faraday waves) largely studied. The means implemented to find the theoretical droplet size distribution which describes ultrasonic atomization as well as possible are, first, analysis of surface waves instability, which allows to determine the average characteristics of the spray, and then, a stochastic method, the maximum entropy formalism, which provides the most probable distribution based on the average characteristics and the elementary laws of conservation applicable to any type of atomization (mass and energy conservation). The experimental validation of this new theoretical approach made it possible moreover to develop new designs of powerful ultrasonic atomizers.

by W. Roth. / "November 26, 1947." "Part of a thesis with the same title." / Bibliographical footnotes. / Army Signal Corps Contract No. W-26-039 sc-32037.

by C. Kittel. / "June 10, 1946." / Includes bibliographical references. / Contract OEMsr-262.

by J.R. Pellam and John Galt. / "June 10, 1946." "OEMsr-262." / Includes bibliographical references.

An investigation was conducted to determine the feasibility of using the technique of ultrasonic nebulization of water into the anode gas stream for evaporative cooling of a Proton Exchange Membrane (PEM) fuel cell. The basic concept of this form of internal evaporative cooling of the PEM fuel cell is to introduce finely atomized liquid water into the anode gas stream, so that the finely atomized liquid water adsorbs onto the anode and then moves to the cathode via electro-osmotic drag, where this water then evaporates into the relatively dry cathode gas stream, carrying with it the waste thermal energy generated within the fuel cell. The thermal and electrical performance of a 50 cm2 PEM fuel cell utilizing this technique was compared to the performance obtained with conventional water management. Both techniques were compared over a range of humidification chamber temperatures for both the anode and cathode gas streams so as to determine the robustness of the proposed method. The proposed method produced only meager levels of evaporative cooling (at best 2 watts, for which a minimum of 30 watts was required for adequate cooling), but the average cell voltage increased considerably (as much as a 10% gain), and the technique increased the fault tolerance of the fuel cell (the Nafion™ membrane did not dry out even if cell temperature went well in excess of 70° C despite both anode and cathode humidification temperatures of 55° C). An interesting phenomena was also observed wherein the fuel cell voltage oscillated regularly with a period of tens of seconds, and that the amplitude of this oscillation corresponded inversely with the level of humidification received by the fuel cell.