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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.
131

The study on the power conversion from a sloshing liquid of U-column

Wu, Chung-yang 31 August 2008 (has links)
This research will use a vibrating U-tube which will cause the water around the tube sway in but will manage the helix leaf blade water turbine which (1998) will develop using Gorlov (Gorlov Helical Turbine). It will also study and discuss electricity generating technology. The vertical motion created external force under the U-tube and about the water will cause the fluid to vibrate and lead the tube cause the domestic water turbine to rotate thus generating electricity. In this article discovers the best size for a generating system and the power rate using the Taguchi method and manufactures the U-tube generating system model and the predecessor gauges the data to make the confirmation, the experimental result discovered the Taguchi method and the actual gauging data best tallies the size. The test results show that in the tube, the fluid oscillation frequency and the blade area rate can affect the structure of the system as well as the true power rate while the external force cycle resonance frequency scope generates electricity.
132

Description de la flore bactérienne digestive per-opératoire néonatale résultats intermédiaires /

Stroesser, Joséphine Caillaux-Varin, Gaëlle January 2008 (has links)
Reproduction de : Thèse d'exercice : Médecine. Pédiatrie : Nantes : 2008. / Bibliogr.
133

Ingestion spontanée d'argiles chez le rat rôle dans la physiologie intestinale /

Reichardt, François Liewig, Nicole. January 2009 (has links) (PDF)
Thèse de doctorat : Sciences du Vivant. Physiologie et biologie des organismes : Strasbourg 1 : 2008. / Titre provenant de l'écran-titre. Bibliogr. 18 p.
134

Les protéines bactériennes en tant que biomarqueurs de l'activité probiotique

Izquierdo Alegre, Esther Marchioni, Eric. Ennahar, Saïd. January 2009 (has links) (PDF)
Thèse de doctorat : Chimie analytique : Strasbourg : 2009. / Thèse soutenue sur un ensemble de travaux. Titre provenant de l'écran-titre. Bibliogr. 19 p.
135

Tube feed or not tube feed is tube feeding a medical treatment? /

Tsang, Tat-Kin. January 2001 (has links)
Thesis (M.A.)--Trinity International University, 2001. / Abstract. Includes bibliographical references (leaves 107-122).
136

Hydraulic transport of single spheres in a horizontal pipe /

Ma, Tsoi-hei. January 1966 (has links)
Thesis (M. Sc.)--University of Hong Kong, 1966. / Mimeographed.
137

Climate change impacts on the serpulid tubeworm Hydroides elegans : a biomineralization perspective

Chan, Bin-san, 陳辯宸 January 2013 (has links)
Atmospheric carbon dioxide (CO2) has increased due to human activity from a pre-industrial value of about 280 ppm to the present level of 399 ppm. The ocean acts as an important natural carbon sink that effectively removes 1/3 of this anthropogenic CO2 from the atmosphere, buffering global warming effects. However, the dissolution of CO2 causes a dramatic change in seawater chemistry and ultimately results in the phenomenon commonly known as "ocean acidification" (OA). As a consequence, the pH value and the saturation states for calcium carbonate decline in the surface seawater, posing a threat to calcareous marine organisms that build their shells using exquisite biomineralization mechanisms. Biological minerals produced by marine organisms are compositionally and structurally more complex than geological minerals. Although changes in biomineral formation in response to OA has been intensively investigated, the features of calcified products in terms of their composition, architectures and mechanical properties have been overlooked in climate change research. The tubeworm is a favourite marine model organism in larval biology. Its life cycle is well understood hence provides a good opportunity to study OA impacts on the stochastic early life. In addition, the model enables comprehensive observation of the sophisticated biomineralization events. In this thesis, four studies on the biomineralization of Hydroides elegans, using a multidisciplinary collaborative approach combining larval biology and material science were conducted. (1) The tube mineral composition at different juvenile stages (4, 11, 18, 25 days) were characterized. (2) The impacts of different predicted OA scenarios (pH 8.1, 7.9, 7.6, and 7.4) on the resultant calcification products were compared. (3) A multiple-stressor investigation of OA (pH 8.1 and 7.8), reduced salinity (33 ‰ and 27 ‰) and increased temperature (25 °C and 29 °C) was conducted to further determine the more environmentally realistic OA impacts. (4) Calcification sites were examined by using a microscopy approach The main findings from each study were: (1) H. elegans produced both calcite and aragonite forms of CaCO3, which have distinctive physical and chemical properties. Thus, the tubeworm serves as an interesting model for studying OA impacts on biomineralization. The early juvenile stages are expected to be more sensitive to OA than the later life stages because the juvenile tubes are rich in aragonite and amorphous calcium carbonate. (2) Under experimental OA conditions, the composition and architecture of the tube structures were adversely affected, ultimately producing tubes with weaker mechanical properties. (3) Warming appeared to strengthen the tube structures and mitigated the adverse OA effects. (4) Calcification sites correlated to regions with higher pH values of 8.5 - 9.0. These regions may be sensitive to OA and should be further analyzed to study the mechanisms of OA impacts on calcification. This series of experiments study biomineralization and larval biology using a variety of modern multidisciplinary approaches provided new insights into the impacts of OA and climate change impacts on marine organisms and also helped us to project which species might adapt or succumb to future scenarios. / published_or_final_version / Biological Sciences / Doctoral / Doctor of Philosophy
138

Pulmonary aspiration in mechanical ventilation

Young, Peter Jeffrey January 1999 (has links)
Pulmonary aspiration in mechanical ventilation occurs despite appropriate inflation of the tracheal tube cuff. After anaesthesiath is can causep ostoperative and, in critically ill patients, ventilator-associated pneumonia. Cuff over-inflation exerts excessive pressure on the tracheal mucosa causing injury. High volume low pressure (HVLP) cuffs permit wall pressure control as the intracuff pressure (CP) is the tracheal wall pressure (TWP). Unfortunately, at the cuff wall, folds and channels and, therefore, fluid leakage occur. Low volume high pressure (LVHP) cuffs develop neither folds nor associated leakage, but TWP is not easily inferred from CP and excessive pressures can result in tracheal injury. This thesis examines the problem of aspiration in a model, in anaesthetised patients and in the critically ill. In the model, protection against leakage resulted from positive end-expiratory pressure and cuff lubrication. Two tracheal cuff prototypes are introduced. Firstly, the compliant HVLP cuff is one with a tapered shape made of highly compliant material. Within the model this produced a circumferential band at the cuff wall without folds thus effectively eliminating channels and leakage. Secondly, the prototype pressure limited cuff (PLC) is a latex LVHP cuff with inflation characteristics such that TWP can be inferred from CP and maintained at an acceptable level. Within the model the PLC prevented leakage at acceptable TWPs. For clinical use a constant pressure inflation device is required to provide uninterrupted protection, although notably HVLP cuffs allow leakage despite this. The PLC prevented dye aspiration in 100% of tracheally intubated critically ill patients compared with 13% of the control HVLP group (p<0.01). A silicone cuff with similar inflation characteristics, yet improved biocompatability and shelf life, prevented dye aspiration in 100% of patients with tracheostomies compared to 0% of the HVLP control group (p=0.001). HVLP cuff lubrication delayed dye aspiration for 1 to 5 days (p<0.05).
139

COMPUTER ANALYSIS OF ACTIVE DEVICES FOR INTEGRATED THERMIONIC CIRCUITS

Feugate, Robert J., 1946- January 1974 (has links)
No description available.
140

Modeling and analysis of dual hydroforming process

Jain, Nishant 30 September 2004 (has links)
The tube hydroforming process has gained increasing attention in recent years. Coordination of the internal pressurization and axial feeding curves is critical in the tube hydroforming process to generate successful parts without fracture or wrinkling failure. The stress state at a given time and location varies with the process history and the design and control of the load paths. A new process parameter, counter-pressure, is introduced to achieve a favorable tri-axial stress state during the deformation process. The new process is referred to as dual hydroforming. The benefits offered by dual hydroforming will be characterized based upon the amount of wall thinning, plastic instability limit and final bulged configuration. An analytical model is developed to analyze the stress and strain state in the part (tube) during the dual hydroforming process. The stress-strain condition analyzed will be used to evaluate and compare thinning for tube hydroforming and dual hydroforming. The effect of applying counter-pressure on the plastic instability of thin-walled tubes with only internal pressure and combination of internal pressure and independent axial loading is considered. Finite element analysis is used to quantify the merits of dual hydroforming in terms of final bulged configuration. A parametric study has been conducted to investigate the effectiveness of dual hydroforming based on the various material properties and process conditions. Dual hydroforming results in different stress and strain states compared to tube hydroforming. The counter-pressure enabled favorable tri-axial stress state during deformation that resulted in different thickness and percentage thinning. Finite element analysis showed that for a particular amount of wall thinning there is an increase of around 8% in bulge height for dual hydroforming. Dual hydroforming delays the onset of plastic instability. This increase in the value of effective strain to failure results in an increase of around 12% in bulge height for dual hydroforming as shown by finite element simulations. Results of this study indicate that dual hydroforming can increase expansion i.e. more difficult parts can be designed and manufactured. Also, for a given part geometry, higher strength and less formable materials can be used.

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