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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.
81

Polymers in surfactant mesophases

Brooks, Jason Travis January 1992 (has links)
No description available.
82

Novel boundary integral formulations for slow viscous flow with moving boundaries

Primo, Ana Rosa Mendes January 1998 (has links)
No description available.
83

A study of liquid film, liquid motion, and oxygen absorption from hemispherical air/oxygen bubbles

Pedersen, Tom January 1998 (has links)
No description available.
84

The behaviour of welded T-end plate connections to rectangular hollow section (RHS)

Omair, Moayad R. January 2000 (has links)
No description available.
85

Neutron reflection from interfaces

Li, Zhi Xin January 1996 (has links)
No description available.
86

Non-contact Measurement of Dynamic Belt Span Tension in Automotive FEAD Systems

Neudorf, Thelma Katherine 05 December 2013 (has links)
The proposed tension measurement method focuses on measurement of tension in a single belt span of the multi-pulley Front End Accessory Drive (FEAD) system. The mean belt span tension is calculated from the measured belt span natural vibration frequency. The oscillation belt span tension is calculated from the measured belt span transverse displacement. The dynamic belt span tension is calculated using the mean and oscillation tensions, belt span support pulley rotations, and belt slip, where the slip equation is based on Euler's equation. The proposed tension measurement method is validated using an experimental testing FEAD system which consists of a five pulley system and an automatic tensioner arm. Non-contact sensors are used to prevent disruption of the typical system behaviour. Testing conditions simulate typical engine crankshaft rotation input. Results from experimental testing consistently produce results with percent error less than 10 % for mean and maximum belt span dynamic tension.
87

Genetic variation of growth, form and wood properties of European beech (Fagus sylvatica L.)

Bienz, Penelope January 1998 (has links)
No description available.
88

The effectiveness of spinal manipulative therapy and trans-cutaneous electrical nerve stimulation versus spinal manipulative therapy and placebo trans-cutaneous electrical nerve stimulation in the treatment of mild to moderate chronic tension-type headache

Fonseca, Shane Warren January 2002 (has links)
A dissertation submitted in partial compliance with the requirements for the Master's Degree in Technology: Chiropractic, Durban Institute of Technology, 2002. / Headaches have been described as the most common medical complaint in society (Dalessia 1987:3), and Tension-type headaches constitute approximately 80% of these (Martin 1993:22). Although Episodic tension-type headache is more prevalent than Chronic tension-type headache and may have a greater societal impact, Chronic tension-type headache has by far a greater individual impact (Schwartz et aI, 1998) on the patient. The exact causes of Chronic tension-type headaches are not known and, as a result, treatment is commonly symptomatic in nature and aimed at reducing pain. To date, treatment commonly involves the use of drugs and with it comes the threat of drug-induced side-effects (Bendtsen et aI, 1996). The purpose of this study was to investigate two non-pharmacological treatments in the management of Chronic tension-type headaches, namely the relative effectiveness of Spinal Manipulative Therapy (SMT) in conjunction with Trans-cutaneous Electrical Nerve Stimulation (TENS), as compared with SMT and placebo TENS. ABSTRACT It was hypothesized that SMT in conjunction with TENS would provide a greater immediate and short-term benefit in comparison to SMT and placebo TENS in the treatment of mild / M
89

Mapping Subcellular Forces Controlling Morphogenesis / Etude du contrôle de la morphogénèse par les forces Sucellulaires

Rauzi, Matteo 10 March 2010 (has links)
Pendant le développement d’un embryon, le remodelage des tissus amène un changement de forme: les tissu peuvent s’allonger, s’envaginer, s’étirer etc. Différentes voies de signalisation règlent ces comportements dans le temps et l’espace à travers le contrôle du cytosquelette d’actine et des tensions produites par ce dernier en interaction avec le moteur moléculaire Myosine-II.Quelle est la distribution des forces subcellulaires qui contrôlent la morphogenèse des tissus? Quelle est la nature des forces engendrée set pour finir, quelle est l’origine de ces forces? Voici les questions pour lesquelles ma thèse cherche des réponses. J’utilise l’élongation de la bande germinale de l’embryon de Drosophile comme système modèle afin d’investiguer la mécanique de la morphogenèse des tissus / During embryonic development tissue remodeling leads to shape changes: for example, tissues can elongate, invaginate, and stretch. Distinct signaling pathways regulate in space and time these behaviors through the control ofthe actin cytoskeleton and of myosin-based tension required for cell shapechange. What is the spatiotemporal pattern of subcellular forcesthat orient tissue morphogenesis? What is the nature of the generated forces and finally, what lies at the origin of such forces? These are the main questions that my thesis tries to illuminate. I use the germbandelongation of the Drosophila embryo as a model system to investigate themechanics of tissue morphogenesis
90

Étude et fabrication de transistors à enrichissement de la filière InAlAs/InGaAs pour applications millimétriques faible bruit / Study, realization and characterization of an E-HEMT on InP substrate with high static and dynamic performances, for low noise applications

El Makoudi, Ikram 23 April 2010 (has links)
Pour les applications électroniques analogiques, des composants fonctionnant en hautes fréquences avec un faible niveau de bruit sont nécessaires. Pour le développement de circuits numériques hauts débits de type DCFL, il faut utiliser des transistors à effet de champ à tensions de seuil positives. De plus, la tenue en tension est aussi une contrainte. La structure HEMT métamorphique à enrichissement AlInAs/GaInAs sur GaAs développée par la société OMMIC en 2007 répond à ces exigences et constitue le point de départ de cette étude. Le but de cette thèse est en effet de fournir une structure de HEMTs à enrichissement (E-HEMTs) de la filière AlInAs/InGaAs pour applications faible bruit sur substrat InP, afin de tirer profit de sa forte mobilité électronique, tout en maintenant de bonnes caractéristiques statiques et dynamiques. Notre travail d’optimisation, de réalisation et de caractérisation de structures permet d’atteindre des fréquences de coupure FT, FMAX de respectivement 204 GHz et 327 GHz, pour un NFmin de 0.96 dB et un gain associé de 13.2 dB à 30 GHz, pour des structures présentant d’excellentes performances statiques : tension de seuil positive de 30 mV, tension de claquage grille - drain de –7 V, transconductance de 1040 mS/mm. Ces résultats placent ce HEMT sur InP à l’état de l’art des transistors HEMTs à enrichissement, et en font un concurrent des transistors HEMTs à déplétion pour les applications faible bruit. / The increasing needs of high frequency electronic systems combined with constant efforts in miniaturization require low noise and high frequency Field Effect Transistor with high operation voltage. For digital applications, enhancement mode HEMT is needed. The enhancement-mode metamorphic AlInAs/GaInAs HEMT on GaAs substrate developed in OMMIC in 2007 meet these requirements and it represents the starting point of our study. The aim of our work is to provide AlInAs/InGaAs E-HEMTs for low noise applications, on InP substrate in order to take advantage of its high electronic mobility, while maintaining high static and dynamic performances. We first optimized the structure, then we realized and characterized E-HEMTs which reach high cutoff frequencies, such as 204 GHz for FT and 327 GHz for FMAX, combined with a low noise figure of 0.96 dB and an associated gain of 13.2 dB at 30 GHz. These structures also show high static performances such as a 30 mV threshold voltage, a gate-to-drain breakdown voltage of –7 V, and a high transconductance of 1040 mS/mm. These results make this pseudomorphic E-HEMT on InP substrate at the state of the art of the enhancement mode HEMTs, and it even competes with the best low noise applications depletion mode HEMTs.

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