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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.
111

Effect of a protective enclosure on the acoustical response of a MEMS directional microphone

Shetye, Mihir Dhananjay. January 2007 (has links)
Thesis (Ph. D.)--State University of New York at Binghamton, Department of Mechanical Engineering, 2007. / Includes bibliographical references (leaves 177-179).
112

Design, analysis and experiment of novel compliant micromanipulators with grippers driven by PZT actuators

Wu, Zhi Gang January 2017 (has links)
University of Macau / Faculty of Science and Technology / Department of Electromechanical Engineering
113

Development and control of a multi-dimensional micromanipulation system for bio-medical engineering

Xiao, Xiao January 2017 (has links)
University of Macau / Faculty of Science and Technology / Department of Electromechanical Engineering
114

Carbon nanotube flow sensors. / CUHK electronic theses & dissertations collection

January 2008 (has links)
Micro-electro-mechanical Systems (MEMS) technology has revolutionized the micro/nano world by making micro/nano devices feasible. These devices allow more exploration and understanding of the micro/nano world. In this dissertation, we will discuss the measurement of wall shear stress in an integrated microfluidic system built by MEMS technology. Specifically, carbon nanotubes (CNTs) were used as the sensing element for gas-flow shear stress measurement in this work. CNTs have already been proven to have an excellent sensing response to temperature, pressure, and alcohol vapour. Based on the thermal sensing response of CNTs, the sensor was designed to operate using convective heat transfer principles in fluid flow. Dielectrophretic manipulation was used to batch fabricate CNTs on a PMMA substrate. The CNT sensor was then integrated into a PMMA microchannel, which was fabricated by a rapid prototyping technique using moulding/hot-embossing processes. The sensor responded to impinging flow as well as gas-flow shear stress. The sensor activation power was found to be linearly related to the 1/3 exponential power of the wall shear stress. With the measurements of an array of sensors, the flow profile of a microchannel with various types of flow could be studied. Compared with the conventional polysilicon sensor, the CNT sensor has the advantage of small dimensions, i.e. a greater spatial resolution for fluidic measurements, and low power consumption, i.e. it consumes ∼1,000 times less power than polysilicon sensors. Therefore, CNT sensors have a great potential to serve as an alternative to silicon-based sensors. / Chow, Wing Yin Winnie. / Adviser: Wen J. Li. / Source: Dissertation Abstracts International, Volume: 70-06, Section: B, page: 3743. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 105-110). / 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, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.
115

Laser-micromachined under-water micro gripper using ionic conducting polymer film (ICPF).

January 2000 (has links)
Kwok, Yiu-fai. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 87-89). / Abstracts in English and Chinese. / ABSTRACT --- p.I / ACKNOWLEDGMENTS --- p.II / TABLE OF CONTENT --- p.III / LIST OF FIGURES --- p.V / Chapter 1 --- INTRODUCTION --- p.1 / Chapter 1.1 --- Background --- p.1 / Chapter 1.2 --- Motivation of this project --- p.1 / Chapter 1.3 --- Organization --- p.2 / Chapter 2 --- LITERATURE SURVEY --- p.3 / Chapter 2.1 --- Ionic Conducting Polymer Film (ICPF) --- p.3 / Chapter 2.2 --- Electroactive Polymer (EAP) --- p.4 / Chapter 2.3 --- Micro Active Guide Wire Catheter System --- p.5 / Chapter 2.4 --- Space Application - Dust Wiper --- p.6 / Chapter 2.5 --- Micro gripper --- p.8 / Chapter 2.6 --- Summary of literature survey --- p.14 / Chapter 3 --- METAL-POLYMER COMPOSITIONS --- p.15 / Chapter 3.1 --- Introduction --- p.15 / Chapter 3.2 --- Perfluorosulfonic acid polymer (Nafion) --- p.15 / Chapter 3.3 --- Working principle of ICPF --- p.19 / Chapter 3.4 --- Different types of composition --- p.21 / Chapter 3.4.1 --- Chromium-Gold-polymer composite --- p.23 / Chapter 3.4.2 --- Platinum-Gold-polymer composite --- p.25 / Chapter 3.4.3 --- Silver-polymer composite --- p.27 / Chapter 3.4.4 --- Silver/Copper-gold polymer composite --- p.27 / Chapter 3.4.5 --- Gold-polymer composite --- p.28 / Chapter 4 --- ICPF FABRICATION --- p.30 / Chapter 4.1 --- Introduction --- p.30 / Chapter 4.2 --- ICPF fabrication process --- p.31 / Chapter 4.3 --- Surface pre-treatment --- p.33 / Chapter 4.4 --- Gold thin film deposition (Evaporation) --- p.34 / Chapter 4.4.1. --- Filament evaporation --- p.35 / Chapter 4.4.2 --- Electronic-beam evaporation --- p.39 / Chapter 4.4.3 --- Structural analysis of evaporation --- p.40 / Chapter 4.5 --- Chemical electroplating --- p.42 / Chapter 4.5.1. --- Deposition rate calibration --- p.44 / Chapter 5 --- DESIGN AND PACKAGE --- p.46 / Chapter 6 --- LASER MICROMACHINING --- p.49 / Chapter 6.1 --- Introduction to Laser micromachining --- p.49 / Chapter 6.2 --- C02 laser --- p.50 / Chapter 6.3 --- Nd:YAG Laser --- p.51 / Chapter 6.4 --- Laser micromachining of ICPF actuator --- p.52 / Chapter 7 --- EXPERIMENTAL RESULTS AND ANALYSIS --- p.61 / Chapter 7.1 --- Introduction --- p.61 / Chapter 7.2 --- Measurement setup --- p.62 / Chapter 7.3 --- Width test --- p.68 / Chapter 7.4 --- Length test --- p.73 / Chapter 7.5 --- Voltage test --- p.76 / Chapter 8 --- MICRO GRIPPER ACTUATION --- p.79 / Chapter 8.1 --- Development of micro gripper --- p.79 / Chapter 8.2 --- Micro gripper --- p.80 / Chapter 9 --- CONCLUSION --- p.82 / Chapter 10 --- APPENDIX --- p.83 / Chapter 10.1 --- Procedures in using E-beam evaporator --- p.83 / Chapter 10.2 --- Procedures in using Thermo couple evaporator --- p.85 / Chapter 11 --- REFERENCE --- p.87
116

A feasibility study of magneto-rheological fluids for micro devices.

January 1999 (has links)
Ho Chi-hong. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves 50-51). / Abstracts in English and Chinese. / Chapter CHAPTER ONE: --- INTRODUCTION --- p.1 / Introduction --- p.1 / Motivation of the Problem --- p.1 / Organization of this Thesis --- p.2 / Chapter CHAPTER TWO: --- LITERATURE SURVEY --- p.3 / Introduction --- p.3 / Electrorheological Fluid --- p.3 / Magnetorheological Fluid --- p.4 / Ferrofluid --- p.4 / "Comparison Amount ER, MR and Ferrofluid" --- p.5 / Chapter CHAPTER THREE: --- THEORETICAL ANALYSIS OF MR FLUIDS FOR MICRO DEVICES --- p.8 / Introduction --- p.8 / Minimal Volume --- p.8 / Magnetic Field Requirement --- p.10 / Particle Size --- p.14 / Chapter CHAPTER FOUR: --- PROCESSING TECHNOLOGY --- p.15 / Introduction --- p.15 / Processing Technology --- p.15 / Chapter CHAPTER FIVE: --- MR FLUID PILLARS --- p.18 / Introduction --- p.18 / Description of Experimental Setup --- p.18 / Finite element Analysis of the Experiment --- p.23 / Alignment Theory of MR Fluid Pillar --- p.29 / Discussion of Fluid Surface Tension --- p.36 / Chapter CHAPTER SIX: --- APPLICATIONS --- p.39 / Introduction --- p.39 / MR Fluid Actuator --- p.39 / Micro Brake --- p.45 / Micro Brake --- p.46 / Micro Clutches --- p.46 / Damper for Micro-Robot System --- p.46 / Chapter CHAPTER SEVEN: --- CONCLUSION --- p.48 / APPENDIX --- p.49 / BIBLIOGRAPHY --- p.50
117

Wireless transmission of embedded mems sensor signal: an experimental study.

January 1999 (has links)
Tsang Tin-Tak. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves 78-80). / Abstract also in Chinese. / Chapter CHAPTER ONE: --- INTRODUCTION --- p.2 / Literature Survey --- p.3 / Project overview --- p.4 / Chapter CHAPTER TWO: --- SENSOR --- p.6 / Chapter 2.1. --- Background --- p.6 / Chapter 2.1.1. --- Piezoresistive effect --- p.6 / Chapter 2.1.2. --- Wheatstone bridge --- p.7 / Chapter 2.2. --- Strain Gauge --- p.10 / Chapter 2.2.1. --- Experimental setup for strain gauge --- p.11 / Chapter 2.2.2. --- Position of the strain gauge --- p.12 / Chapter 2.2.3. --- Selection of the value for the resistor to complete the bridge --- p.13 / Chapter 2.3. --- Pressure sensor --- p.15 / Chapter 2.3.1. --- Structure of pressure sensor die --- p.15 / Chapter 2.3.2. --- Modeling of the pressure sensor die --- p.17 / Chapter 2.3.3. --- Alternative application of the pressure sensor die --- p.20 / Chapter CHAPTER THREE: --- WIRELESS TRANSMISSION --- p.24 / Chapter 3.1. --- Introduction --- p.24 / Chapter 3.2. --- Analogue Transmission --- p.25 / Chapter 3.2.1. --- Transmitter (MC2833) --- p.26 / Chapter 3.2.2. --- Receiver (MC13135) --- p.29 / Chapter 3.3. --- Digital transmission --- p.30 / Chapter 3.3.1. --- Advantage of using Digital transmission --- p.30 / Chapter 3.3.2. --- Digital Transmitter and receiver 1 (H2000 & RX2020) --- p.30 / Chapter 3.3.3. --- Digital Transmitter and receiver 2 (TX2) --- p.32 / Chapter 3.4. --- Comparison between the three sets of transmitter --- p.34 / Chapter 3.4.1. --- Analogue Vs Digital --- p.34 / Chapter 3.4.2. --- Number of components (Complexity) --- p.35 / Chapter 3.4.3. --- Excepted size --- p.35 / Chapter 3.4.4. --- Transmitting distance --- p.36 / Chapter 3.4.5. --- Power supply --- p.36 / Chapter 3.4.6. --- Conclusion --- p.36 / Chapter 3.5. --- The detail investigation of HX2000 and RX2020/RX2056 --- p.37 / Chapter 3.5.1. --- Transmitting distance --- p.37 / Chapter 3.5.2. --- Shape of the received signal --- p.37 / Chapter 3.5.3. --- Orientation of the chips --- p.39 / Chapter 3.5.4. --- Conclusion for the transmitter --- p.39 / Chapter CHAPTER FOUR: --- ENCODING AND DECODING CIRCUIT --- p.40 / Chapter 4.1. --- Introduction --- p.40 / Chapter 4.2. --- Serial binary converter (MAX 1240) --- p.40 / Chapter 4.2.1. --- Features of MAX1240 --- p.41 / Chapter 4.2.2. --- Implementation of MAX1240 --- p.43 / Chapter 4.2.3. --- Method to decode the signal generated by MAX1240 --- p.46 / Chapter 4.3. --- Voltage-to-Frequency Converter (AD654) --- p.52 / Chapter 4.3.1. --- Advantages of using AD654 as the A/D converter --- p.54 / Chapter 4.3.2. --- Disadvantages of using AD654 as the A/D converter --- p.55 / Chapter 4.3.3. --- Method to read the frequency --- p.56 / Chapter 4.4. --- Frequency counter --- p.57 / Chapter 4.4.1. --- Schmitt trigger NAND-gate --- p.58 / Chapter 4.4.2. --- Ripple counter --- p.61 / Chapter 4.4.3. --- Implementation of the counter --- p.63 / Chapter 4.5. --- Conclusion --- p.66 / Chapter CHAPTER FIVE: --- INTERGATION OF THE THREE COMPONENTS --- p.67 / Implementation of the Circuit --- p.67 / Chapter 5.2. --- The result before transmission --- p.70 / Chapter 5.2.1. --- Analysis and Discussion for the experimental result (before transmission) --- p.72 / Chapter 5.3. --- The result after transmission --- p.74 / Chapter 5.3.1. --- Analysis and Discussion for the experimental result (after transmission) --- p.76 / Chapter CHAPTER SIX: --- SUMMARY --- p.77 / BIBLIOGRAPHY --- p.78
118

Non-contact batch micro-assembly by centrifugal force.

January 2002 (has links)
Lai, Wai Chiu King. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (leaves 87-89). / Abstracts in English and Chinese. / LIST OF TABLES --- p.vi / LIST OF FIGURES --- p.vii / Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- Background --- p.1 / Chapter 1.2 --- Organization of the thesis --- p.3 / Chapter 2. --- Literature Survey --- p.5 / Chapter 2.1 --- Micro Hinges --- p.5 / Chapter 2.2 --- Assembly --- p.5 / Chapter 2.2.1 --- Manual Lift Up Process --- p.5 / Chapter 2.2.2 --- Assembly by On-substrate Actuators --- p.6 / Chapter 2.2.3 --- Assembly by Surface Tension Force --- p.8 / Chapter 2.2.4 --- Assembly by Thermal Shrinkage --- p.8 / Chapter 2.2.5 --- Assembly by Ultrasonic Triboelectricity --- p.9 / Chapter 2.3 --- Summary of Literature Survey --- p.9 / Chapter 3. --- Design & Analysis --- p.11 / Chapter 3.1 --- Micro-Assembly by Centrifugal Force --- p.11 / Chapter 3.2 --- Micro Mass Platform --- p.12 / Chapter 3.2.1 --- Micro Mirror --- p.12 / Chapter 3.2.2 --- Rotation Sensor --- p.15 / Chapter 3.3 --- Fabrication of Micro Structures --- p.16 / Chapter 3.4 --- Force Analysis --- p.18 / Chapter 3.4.1 --- Centrifugal Force --- p.18 / Chapter 3.4.2 --- Van der Waals Forces --- p.20 / Chapter 3.4.3 --- Capillary Force - (1st model) --- p.22 / Chapter 3.4.4 --- Capillary Force - (2nd model) --- p.23 / Chapter 3.4.5 --- Casimir Force --- p.26 / Chapter 3.4.6 --- Spring force of the beam --- p.27 / Chapter 3.4.7 --- Comparison of Forces --- p.28 / Chapter 3.4.8 --- Stress on Polysilicon --- p.30 / Chapter 4. --- Surface Force Measurement --- p.32 / Chapter 4.1 --- Experimental Setup --- p.33 / Chapter 4.2 --- Experimental Result --- p.34 / Chapter 4.2.1 --- Control Experiment of Rotation Sensor --- p.34 / Chapter 4.2.2 --- Freed-state and Snap-down-state --- p.35 / Chapter 4.2.3 --- Summary of the Experimental Data --- p.36 / Chapter 4.3 --- Comparison between Modelled Results and Experimental Data --- p.42 / Chapter 5. --- Assembly Experiment --- p.45 / Chapter 5.1 --- Experimental Setup --- p.45 / Chapter 5.2 --- Experimental Results --- p.46 / Chapter 5.3 --- Comparison among different chips --- p.52 / Chapter 6. --- Assembly Experiment (Double Chips) --- p.57 / Chapter 6.1 --- Experimental Setup --- p.57 / Chapter 6.2 --- Experimental Results --- p.58 / Chapter 6.2.1 --- Surface Profile measurement --- p.58 / Chapter 6.2.2 --- Summary of the surface profile measurement --- p.68 / Chapter 6.2.3 --- Assembly Results --- p.69 / Chapter 7. --- Assembly Experiment (Monitoring System in MUMPs46) --- p.72 / Chapter 7.1 --- Experimental Setup --- p.72 / Chapter 7.2 --- Experimental Results --- p.74 / Chapter 8. --- Other tested micro structures --- p.80 / Chapter 9. --- Conclusion --- p.82 / Chapter 10. --- Future Work --- p.83 / Chapter A. --- Appendix --- p.84 / Bibliography --- p.87
119

MEMS resonators for low power wireless communications and timing applications

Erbes, Andreja January 2015 (has links)
No description available.
120

Micro input devices system (MIDS) using MEMS sensors. / CUHK electronic theses & dissertations collection

January 2004 (has links)
by Lam Hiu-fung. / "Augustr 2004." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (p. 178-182). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

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