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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.
1

Taiwanese coil steel enterprises value creation modulus competitive advantage strategy for mainland China steel market

HUANG, JENN-YIH 29 July 2003 (has links)
The researches try to find suitable competitive advantage business modulus to run mainland China market for Taiwanese coil steel enterprises. We suggest them competitive strategy for mainland China coil steel market. Taiwanese coil steel enterprises usually enlarge product capacity strategy decreasing product unit cost to increase oversea market share. They enlarge product capacity quickly. The majority coil steel users transfer their base of manufacture to mainland China such as steel pipe manufacture, computer supplement equipment , bicycle component, motorcycle component, house electrical supplement component, sport equipment, steel furniture. Taiwanese coil steel enterprises loss money as overcapacity. The situation is changeable because mainland China market increases demand recently. The international trade steel unit price reaches the highest record during decade. China is the most amount steel importing country in the world. The flourish China steel market benefits Taiwanese coil steel enterprises all. The competitive advantage should match suitable value creation modulus that makes competitive advantage enhance effect. We call on 110 Taiwanese coil steel correlated enterprises sales mangers. Regional consolidation, specialization and downstream migration, deconstruction and global networking are three kinds value creation modulus. We inquire their opinion to choice one value creation strategy from three value creation modulus. This value creation strategy matches competitive advantages which are low cost, differentiation, focus, entrepreneurship and integration. The statistics of questionnaires conclude Specialization and downstream migration to be the best value creation strategy.
2

Design and analysis of linear induction accelerators

Horne, Christopher Douglas January 1993 (has links)
No description available.
3

Xmc, a novel Xenopus laevis organiser : gene regulating gastrulation movements

Frazzetto, Giovanni January 2002 (has links)
No description available.
4

Radio-frequency coil design for magnetic resonance imaging and spectroscopy

Cassidy, Paul Joseph January 2002 (has links)
No description available.
5

An investigation of array elements for enhanced single echo acquisition imaging

Dominick, Colleen Elizabeth 30 October 2006 (has links)
Rapid MR imaging has facilitated the development of a variety of medical tools such as MR guided surgeries, drug delivery, stent placement, biopsies, and blood flow imaging. This rapid imaging is largely attributable to the development of parallel imaging techniques. In one such technique, single echo acquisition (SEA) imaging, scan time is reduced by substituting the lengthy phase encoding process with spatial information from an extensive receiver coil array. In order to easily construct and obtain images from this coil array, an ideal set of coil elements would be easily decoupled and tuned, possess high SNR and penetration depth, and would allow for operation in both transmit and receive mode. Several types of coils have been considered for use in massive coil arrays, including the planar pair coil, the loop coil and the stripline coil. This thesis investigates each of these coils for use in massive arrays for SEA imaging with enhanced penetration. This investigation includes: improving the currents on the planar pair coil, determining the feasibility of the loop coil and the stripline coil at the scale required for SEA, and comparing the salient properties of each coil type. This investigation revealed that the stripline coil appears to be the best coil element for SEA imaging with enhanced penetration.
6

An investigation of array elements for enhanced single echo acquisition imaging

Dominick, Colleen Elizabeth 30 October 2006 (has links)
Rapid MR imaging has facilitated the development of a variety of medical tools such as MR guided surgeries, drug delivery, stent placement, biopsies, and blood flow imaging. This rapid imaging is largely attributable to the development of parallel imaging techniques. In one such technique, single echo acquisition (SEA) imaging, scan time is reduced by substituting the lengthy phase encoding process with spatial information from an extensive receiver coil array. In order to easily construct and obtain images from this coil array, an ideal set of coil elements would be easily decoupled and tuned, possess high SNR and penetration depth, and would allow for operation in both transmit and receive mode. Several types of coils have been considered for use in massive coil arrays, including the planar pair coil, the loop coil and the stripline coil. This thesis investigates each of these coils for use in massive arrays for SEA imaging with enhanced penetration. This investigation includes: improving the currents on the planar pair coil, determining the feasibility of the loop coil and the stripline coil at the scale required for SEA, and comparing the salient properties of each coil type. This investigation revealed that the stripline coil appears to be the best coil element for SEA imaging with enhanced penetration.
7

A high-pass detunable quadrature birdcage coil at high-field

Kampani, Vishal Virendra 10 October 2008 (has links)
The circuit described in this study is intended for Magnetic Resonance Imaging (MRI) application. The function of this circuit is to transmit RF energy to the sample and then receive the RF energy. The circuit that does this is called a birdcage coil. This coil is capable of producing a very homogenous B1 field over a large volume; it is this aspect of birdcage coils that make them very favorable for animal/human studies as it is necessary that all nuclei in the volume of the coil are excited by uniform RF energy. At high-field (4.7T) when the power is fed to the coil at a single port the coil unable to produce a homogenous B1 field. However when power is fed at multiple ports the performance of the coil improves. In this paper a study is carried out comparing the performance of the coil when power is fed at a single port and two ports. The advantage of feeding at two ports is that there is sqrt(2) improvement in SNR and the RF power efficiency is doubled. In this work strategies are presented for matching, tuning and isolating the two ports. Also, an attempt is made to fabricate a mechanically rigid coil and interfacing the coil with some additional features that will make the coil easy to use. The homogeneity and SNR of a birdcage coil in linear and quadrature mode loaded with saline, oil and CuSO4 phantom was measured on the bench and the scanner. The coil performance was compared to two other birdcage coils in the lab. It was found that the unshielded trombone coil that was 3 times smaller in volume than the coil presented has 140% higher SNR than the coil presented but the homogenous region of the coil presented is 48% higher than the smaller coil. Lastly on the bench; the SNR of the quadrature coil was 30% higher than the coil in the linear mode.
8

The fatigue properties of spring steel

Hattingh, Daniel Gerhardus January 1998 (has links)
The nature and scope of this thesis can be divided into three categories, namely stress distribution modelling in coil springs; fatigue and failure analysis, an investigation into measurement of residual stresses and the relation to fatigue life. The operation of springs is directly concerned with the theories of torsion and bending which makes the better understanding of these theories essential. The first part of the thesis is involved with a mathematical evaluation of these theories and a case study of an isolated loop of a coil spring. The mathematical modelling is verified by measuring the strain levels in a coil spring with the aid of strain gauges located at different positions in the coil spring. This evaluation gave a better understanding of the operational stress distribution for input into the two methods currently used by industry for the fatigue testing, namely isolated loop and complete coil spring samples. The remaining part of the thesis revolves around the understanding of the relationship between fatigue life, process effects and residual stresses. The relationship between fatigue failures and process effects was investigated to reveal the mechanism responsible for component fatigue failure in a 55Cr3 automotive suspension spring steel. This was done by subjecting coil springs, withdrawn from different stages of the manufacturing process, to fatigue tests, ensuring that all possible sources of fatigue initiation in this material batch have been identified, including those not dominant in the finished component. Failures prior to shot peen process was mainly surface relate as where those withdrawn after this process were subsurface (inclusions) related. Fractographic analysis, using an XL30 scanning electron microscope, has revealed a number of sources of initiation, which are largely related to mechanical damage and inherent material defects. The results indicate that decreasing defect levels in the material would represent a valid method for enhancing the fatigue response, specifically levels of nonmetallic inclusions and surface mechanical damage, but also that certain manufacturing process stages (cold scragg) are responsible for drop in fatigue life.
9

THREE-DIMENSIONAL MONOLITHIC MEMS COIL

SUN, JING January 2003 (has links)
No description available.
10

Fabrication and cryogenic stabilisation of (Bi,Pb)SrCaCuO-2223 superconducting tapes

Penny, Marcus David January 1998 (has links)
No description available.

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