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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.
241

The Design of Sliding Mode Controller for Mold Level Control System

Zheng, Wan-Sheng 27 August 2001 (has links)
A sliding mode controller is proposed for controlling molten steel level in a mold of continuous casting machine in this thesis. The comparisons of dynamic response, control accuracy, and reaction to perturbation between proposed controller and PID controller currently used are also presented. A perturbation estimator is embedded in the sliding mode controller in order to enhance the robustness against model uncertainty, parameter variation, and external disturbance. The perturbation considered in this thesis includes variation of casting speed, variation of area of slide gate, time delay, variation of mold area, and Dead-Band etc.. In addition, the effects of adjusting the design parameter of the proposed controller on system¡¦s dynamics are also considered.
242

Retailer Entry Mode in China

Mai, Chia-Jung 20 June 2002 (has links)
China is the second largest investing market in the world now and it is also the number ninth trading country in the world. There are almost 13 billion populations in China, average GDP each year is about 7%. We can see how attractive and interesting China market is for all the retailers in the world and top 500 countries are all interested in investing in China. Since 1992 China government opened retailer¡¦s market and policy, almost all the MNC companies, local Chinese retailers, small retailers and ¡K¡Ketc, are eager to enter China. It also helps China retailer market full of lot of competitions. It¡¦s also good timing for us to obverse retailer¡¦s entry mode in China. When we are facing the global competition around the world and changing everywhere. For MNC companies, it¡¦s a great challenge to keep sustainable competitive advantage and do the right direction. The purpose of the study is knowing retailer¡¦s entry mode in china, how the motivations affect companies to choose the entry mode in china. This paper is different then the general entry mode theory we know, it¡¦s the result after observing the market phenomenon, case study, interview Carrefour & 7-11, scholar¡¦s experience and discussion. After that I try to combine all the materials above and find out the true phenomenon of retailing market in china and make the conclusion for all retailers who wants to enter China. As we know different entry motivations will affect retailers to choose different entry mode. In this paper, I put on the Company side, Risk side, Environment side and Local operation side. Try to understand how the four side affect retailers¡¦ choose the entry mode in China. This paper starts from the different entry motivations, four different sides evaluation, and try to find the appropriate retailer¡¦s entry mode in China for all the companies who may want to enter china.
243

Improvement in the Bandwidth performance of VDSL2 Splitter

Lin, Tzu-Hua 22 January 2008 (has links)
The currently used DSL splitters or filters are designed for ADSL band up to 1104 KHz and ADSL2+ band up to 2208 KHz. To meet faster internet access, DSL technology has evolved from ADSL into VDSL2 with an operating band up to 30 MHz. However, the splitters in VDSL2 band have some design difficulties in longitudinal conversion loss and isolation. The main purpose of this thesis is to find some solutions to overcome these design difficulties for splitters operating in VDSL2 band. The proposed solutions include the use of common-mode choke and compensation circuit. The final testing results of the splitters can validate the proposed solutions.
244

Operation Modes Prediction of a High Speed Rotor with Dual-Point Measurement

Lin, Chang-ming 06 August 2009 (has links)
This paper adopts a dual-point measurement technique to predict the resonance frequency and operation modes of a high speed rotor at different operating speed. The effect of balance policy on the operating mode shapes of a rotor has also been investigated. Displacement signals measured at two different points of a rotating shaft are used to estimate the operation mode shapes at the main operating frequency based on the definition of transmissibility function. To verify the feasibility of this technique, the dynamic parameters, i.e. natural frequencies, damping ratio and normal modes of a stationary rotor are measured in advance by applying the traditional frequency response method for comparison. The values of modal assurance criterion (MAC) and mode shape diagrams indicate that both methods are in a good agreement on the normal modes when the system is undamped or lightly damped. However, a significant difference is observed for highly damped modes. The dual-point measurement technique is applicable to investigate the effect of rotating speed on measured operation modes at different speed. Results indicate that the rotating speed may affect the dynamic parameters of a rotating shaft significantly. Furthermore, the dynamic unbalance effect on the response of a rotating shaft has also been studied in this thesis. Results indicate that the position of the unbalance is quite sensitive to the response of a rotating shaft. The sensitivity of unbalance and its position is dependent on the operation mode correspondence to the driving speed. The measured results indicate the dual-point measurement is quite available to study the dynamic responses of a rotating shaft or rotor.
245

Spinoza : la science mathématique du salut /

Barbaras, Françoise, January 1900 (has links)
Texte remanié de: Thèse de doctorat--Philosophie--Paris 1, 2003. / Bibliogr. p. 191-196. Index. L'ISSN exact est : 1248-5284.
246

Etude du costume impérial à partir des portraits de la famille Clarke par F. X. Fabre /

Serène, Chantal. January 2004 (has links)
Maîtrise--Histoire de l'art moderne--Montpellier III, Université Paul Valéry, 2004. / Bibliogr. p. 182-189.
247

Commande non-linéaire d'une machine asynchrone à double alimentation

Vidal, Paul-Etienne Pietrzak-David, Maria. January 2005 (has links)
Reproduction de : Thèse de doctorat : Génie électrique : Toulouse, INPT : 2004. / Titre provenant de l'écran-titre. Bibliogr. 74 réf.
248

Stable optical frequency comb generation and applications in arbitrary waveform generation, signal processing and optical data mining

Ozharar, Sarper. January 2008 (has links)
Thesis (Ph.D.)--University of Central Florida, 2008. / Adviser: Peter J. Delfyett, Jr. Includes bibliographical references (p. 123-130).
249

Measurement-based traffic modeling and network resource management /

Che, Hao. January 1998 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 1998. / Includes bibliographical references (leaves 145-154). Available also in a digital version from Dissertation Abstracts.
250

Nazi "chic"? : fashioning women of the Third Reich /

Guenther, Irene. January 2001 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2001. / Vita. Includes bibliographical references (leaves 551-588). Available also in a digital version from Dissertation Abstracts.

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