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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.
21

A seismic magneto-rheological (MR) fluid by-pass damper

Bangrakulur, Krishna Kiran. January 2004 (has links)
Thesis (M.S.)--University of Nevada, Reno, 2004. / "December 2004." Includes bibliographical references (leaves 70-72). Online version available on the World Wide Web.
22

PDMS based microfluidic chips and their application in material synthesis /

Gong, Xiuqing. January 2009 (has links)
Includes bibliographical references (p. 94-108).
23

Continuous variable transmission and regenerative braking devices in bicycles utilizing magnetorheological fluids. / CUHK electronic theses & dissertations collection

January 2013 (has links)
Cheung, Wai Ming Edwin. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 107-112). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts also in Chinese.
24

A magneto-rheological actuator for assistive knee braces. / CUHK electronic theses & dissertations collection

January 2009 (has links)
It has been found that magneto-rheological (MR) devices can produce large controllable force/torque while consuming little power. In this research, an MR actuator that can function as a clutch or a brake is developed, in order to be applied to an assistive knee brace. The torque capability and dynamic characteristics of the MR actuator are evaluated. The relationship between the torque output and the applied coil current is given. The response time is also measured. Experimental results show that the MR actuator can provide enough torque for normal activities with sufficiently fast response. IP control and adaptive control are proposed to control the MR actuator. Experiments under these controls are carried out. With anti-windup strategies, both controls achieve good performances. However, adaptive control would be more promising since it can adapt to parameter variations and maintain good performance. An assistive knee brace that contains this MR actuator and a DC motor is developed. In order to study the performances of the knee brace before applied to human body, experiments are conducted for evaluation under a custom-built testing structure. IP-based state control and adaptive control are used to control both the MR actuator and DC motor. Experimental results demonstrate that the MR actuator and DC motor work well together to provide assistance as expected. Compared with that without MR actuator, the evaluation results show that the knee brace with MR actuator is more energy efficient during normal walking, while having better force controllability and safety. / by Chen, Jinzhou. / Adviser: Liao Wei Hsin. / Source: Dissertation Abstracts International, Volume: 73-01, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 140-151). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
25

Design and analysis of multifunctional actuators for assistive knee braces. / CUHK electronic theses & dissertations collection

January 2010 (has links)
In this research, a novel magnetorheological (MR) fluids based multifunctional actuator for assistive knee braces is designed. To decrease the dimension of the actuation device while enhancing its perfonnances, a motor and MR fluids are integrated into a single device. With MR fluids, the actuator possesses multiple functions as motor, clutch, and brake while meeting the requirement of nonnal human motion as well. In this thesis, design details and operating principle of the actuator are illustrated, and possible configurations of the motor part and clutch/brake part are discussed. Finite element method is utilized to analyze the magnetic circuits, influence of pennanent magnet on MR fluids, and magnetic flux distribution. Different clutch/brake parts with various inner coils are compared and analyzed, followed by a design optimization to improve the output torque. Prototypes of the multifunctional actuator are fabricated and tested, and characteristics of each function are investigated. As the actuator has multiple functions, modeling is developed for different functions, and system identification is carried out to determine the parameters. Adaptive control is utilized to control the actuator for torque and speed tracking. A smart joint using such a multifunctional actuator is designed, and its prototype is fabricated and tested. Power consumptions of knee brace using the smart joint are investigated during normal walking cycle. The results show that the developed actuator and smart joint are promising to be used in assistive knee braces. / Guo, Hongtao. / Source: Dissertation Abstracts International, Volume: 73-03, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 154-158). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
26

A new unified theory for flow analysis of a magneto-rheological (MR) fluids and application of MR fluids in a high-torque clutch

Kavlicoglu, Barkan M. January 2006 (has links)
Thesis (Ph. D.)--University of Nevada, Reno, 2006. / "December, 2006." Includes bibliographical references (leaves 129-135). Online version available on the World Wide Web.
27

Mathematical modelling of nano-scaled structures, devices and materials

Cox, Barry James. January 2007 (has links)
Thesis (Ph.D.)--University of Wollongong, 2007. / Typescript. Includes bibliographical references: leaf 206-217.
28

Topics in the theory of inhomogeneous media composite superconductors and dielectrics /

Kim, Kwangmoo, January 2007 (has links)
Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references (p. 166-181).

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