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Dissertations / Theses on the topic 'Electromechanical Engineering – Department of Electromechanical Engineering'

Author: Grafiati

Published: 4 June 2021

Last updated: 1 February 2022

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1

Leong, Hoi San. "Effect of corrosion inhibitor and laser surface treatment on corrosion behavior of steel used in chilling system." Thesis, University of Macau, 2011. http://umaclib3.umac.mo/record=b2550589.

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2

Cheong, Chan Wa. "Development of heat transfer correlation and flow regime map for heated horizontal pipe using support vector machines." Thesis, University of Macau, 2011. http://umaclib3.umac.mo/record=b2493970.

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3

Wen, Quan. "An experimental investigation of inner surface roughness on friction factor for horizontal micro-tubes." Thesis, University of Macau, 2010. http://umaclib3.umac.mo/record=b2493677.

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4

Sio, Sei Hoi. "Concurrent engineering in modern mold design and production." Thesis, University of Macau, 2001. http://umaclib3.umac.mo/record=b1446138.

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5

Leong, Iok Sam. "An investigation of the usage of small scale furnace for fire resistance test." Thesis, University of Macau, 2006. http://umaclib3.umac.mo/record=b1446610.

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6

Zhong, Jian Hua. "Intelligent system based facility monitoring and fault diagnosis of power generators." Thesis, University of Macau, 2011. http://umaclib3.umac.mo/record=b2550655.

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7

Zhang, Zai Yong. "Simultaneous fault diagnosis of automotive engine ignition systems using pairwise coupled relevance vector machine, extracted pattern features and decision threshold optimization." Thesis, University of Macau, 2011. http://umaclib3.umac.mo/record=b2493967.

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8

Chong, Ian Ian. "Vibration control and genetic algorithm based design optimization on self-sensing active constrained layer damped rotating plates." Thesis, University of Macau, 2011. http://umaclib3.umac.mo/record=b2493698.

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9

Wong, Ian Kai. "Numerical study of stokes' second flow problem." Thesis, University of Macau, 2011. http://umaclib3.umac.mo/record=b2550664.

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10

Chan, Lai Cheong. "Investigation on energy efficiency of electrical power system in Macau Coloane power plant." Thesis, University of Macau, 2012. http://umaclib3.umac.mo/record=b2586280.

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11

Yun, Yuan. "Kinematics, dynamics and control analysis for micro positioning and active vibration isolation using parallel manipulators." Thesis, University of Macau, 2011. http://umaclib3.umac.mo/record=b2542954.

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12

Mok, Keng Wa. "Design and control of an electromechanical variable rotary valve system for four-stroke engines." Thesis, University of Macau, 2008. http://umaclib3.umac.mo/record=b1942819.

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13

Lao, Seng Kin. "Computer-aided analysis for combined building services drawings using Real-coded Genetic Algorithm." Thesis, University of Macau, 2001. http://umaclib3.umac.mo/record=b1446119.

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14

Sou, Kun Tou. "Microorganism control for air conditioning systems using ultraviolet light." Thesis, University of Macau, 2002. http://umaclib3.umac.mo/record=b1446149.

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15

Fong, Siu Lung. "Corrosion study of laser welded stainless steels." Thesis, University of Macau, 2002. http://umaclib3.umac.mo/record=b1446156.

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16

Leong, Sio Hong. "Kinematics control of redundant manipulators using CMAC neural networks combined with Descent Gradient Optimizers & Genetic Algorithm Optimizers." Thesis, University of Macau, 2003. http://umaclib3.umac.mo/record=b1446170.

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17

Lee, Kyaw Wee. "Study on solar-powered hybrid electric compressor for automotive air-conditioning systems." Thesis, University of Macau, 2005. http://umaclib3.umac.mo/record=b1446185.

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18

Lei, Wai Ip. "A multi agents control approach to robot soccer competition." Thesis, University of Macau, 2004. http://umaclib3.umac.mo/record=b1446190.

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19

Li, Ke. "Development of a novel electro-hydraulic fully variable valve-train for four stroke automotive engines." Thesis, University of Macau, 2005. http://umaclib3.umac.mo/record=b1446198.

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20

Tam, Hou Kuan. "An improved convective heat transfer correlation for gas-liquid two-phase pipe flow." Thesis, University of Macau, 2004. http://umaclib3.umac.mo/record=b1446601.

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21

Ding, Wen He. "Passivation of stainless steels for medical applications." Thesis, University of Macau, 2006. http://umaclib3.umac.mo/record=b1636557.

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22

Leong, Ka Ip. "Laser surface modification of tool steels for enhancing surface properties." Thesis, University of Macau, 2006. http://umaclib3.umac.mo/record=b1636564.

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23

Sun, Ho I. "Experimental investigations and simulations of indoor air quality for wet market." Thesis, University of Macau, 2006. http://umaclib3.umac.mo/record=b1636571.

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24

Du, Shao Rong. "An investigation on nanomanipulation based on atomic force miscroscope." Thesis, University of Macau, 2008. http://umaclib3.umac.mo/record=b1636971.

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25

Choi, Hong Fei. "Numerical simulation of atrium fire using two CFD tools." Thesis, University of Macau, 2007. http://umaclib3.umac.mo/record=b1694321.

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26

Si, Tou Wai Meng. "An Investigation of the dynamic behaviors of the chaotics Chen-Lee system." Thesis, University of Macau, 2007. http://umaclib3.umac.mo/record=b1694327.

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27

Cheang, Kuok Mao. "Development of vehicle and motorbike driving cycles for Macau." Thesis, University of Macau, 2008. http://umaclib3.umac.mo/record=b1942812.

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28

Novo, Fabio da Mota Ferreira. "Condition monitoring based systematic modeling of equipment maintenance." Thesis, University of Macau, 2008. http://umaclib3.umac.mo/record=b1942840.

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29

Wong, Po Kee. "Corrosion study of nano-hydroxyapatite coatings on implant alloys fabricated by electrophoretic deposition." Thesis, University of Macau, 2008. http://umaclib3.umac.mo/record=b1942845.

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30

Lei, Keng U. "Development of vehicle fleet management system based on Global Positioning System and artificial intelligencet." Thesis, University of Macau, 2008. http://umaclib3.umac.mo/record=b1942982.

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31

Wong, Kit Iong. "ETS measurements and ventilation strategies for indoor environment." Thesis, University of Macau, 2008. http://umaclib3.umac.mo/record=b1942988.

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32

Ng, Ka Ian. "Optimization of automotive engine power performance under numerical and nominal data." Thesis, University of Macau, 2008. http://umaclib3.umac.mo/record=b1942992.

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33

Chang, Fong Long. "Computer-aided calibration for compensation maps of engine management systems." Thesis, University of Macau, 2008. http://umaclib3.umac.mo/record=b1942994.

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34

Li, Ke. "Automotive engine tuning using least-squares support vector machines and evolutionary optimization." Thesis, University of Macau, 2012. http://umaclib3.umac.mo/record=b2580667.

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35

Xu, Qing Song. "Design, analysis, and control of parallel robots with different applications." Thesis, University of Macau, 2008. http://umaclib3.umac.mo/record=b1783645.

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36

Zhai, Pei. "The hybrid real-time simulation system based on the electromechanical transient process simulation of power systems." Thesis, University of Macau, 2007. http://umaclib3.umac.mo/record=b1678026.

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37

Chen, Xin. "Modeling swarm intelligence and its applications in robotics and optimization." Thesis, University of Macau, 2007. http://umaclib3.umac.mo/record=b1675661.

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38

Xu, Qing Song. "Kinematics, dynamics and control of parallel robots." Thesis, University of Macau, 2004. http://umaclib3.umac.mo/record=b1446180.

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39

Quan, Lu Lin. "An investigation on 3D shape similarity assessment for design re-usage." Thesis, University of Macau, 2009. http://umaclib3.umac.mo/record=b2144075.

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40

Sin, Vai Kuong. "Particle dispersion in two-phase turbulent flows." Thesis, University of Macau, 2000. http://umaclib3.umac.mo/record=b1637076.

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41

Wong, Hang Cheong. "Design and experimental evaluation of predictive engine air-ratio control using relevance vector machine." Thesis, University of Macau, 2009. http://umaclib3.umac.mo/record=b2182947.

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42

Chu, Angela (Angela J. ). "Prototyping practices in electromechanical startups." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/92604.

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Thesis: S.B., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2014.<br>This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.<br>Cataloged from student-submitted PDF version of thesis.<br>Includes bibliographical references (page 24).<br>Electromechanical startups contend with signicant uncertainty, especially in early stages of development. Prototyping is a critical component through the product development process, and when employed eciently, can act as a method for mitigating risk associated with product viability for founders and funders. While extensive research has been conducted on prototyping practices in industry, there has been little investigation into prototyping for electromechanical startups. This research aims to understand current prototyping practices in these environments by answering the following questions. What kinds of prototypes do startups develop? What functions do these prototypes serve? What are the relevant traits that make these prototypes conducive to these functions? To develop a formal questionnaire, preliminary interviews with two startups were conducted. A case study was also conducted of prototyping practices in 2.009 Product Engineering Processes, an undergraduate course at MIT. Following this, secondary interviews were held with members of three additional startups. From a sample of 52 identied prototypes, relationships were found between the material categorizations of prototypes and three key functional roles: test, clarify, and communicate. To further understand the prototyping choices of startups, material categorizations were evaluated with respect to eight core prototype characteristics. Results show that prototypes favored for testing were physically interactive, such as 3D sketches or digitally fabricated models. Inexpensive and easy-to-alter representations (2D sketches, 3D sketches, and CAD) were created to clarify concepts. Visually appealing models (CAD, 2D sketches) were used heavily for both internal and external communication.<br>by Angela Chu.<br>S.B.

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43

Yaglioglu, Onnik 1976. "Carbon nanotube based electromechanical probes." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/40357.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2007.<br>Includes bibliographical references (p. 131-137).<br>Electromechanical probing applications continuously require smaller pitches, faster manufacturing and lower electrical resistance. Conventional techniques, such as MEMS based cantilever probes have their shortcomings in terms of the lowest pitch that can be achieved, cost and yield. Given their promising mechanical and electrical properties, carbon nanotubes (CNTs) are strong candidates for future probing applications. A new class of metal-CNT hybrid electromechanical probes is presented where vertically aligned carbon nanotube structures, grown with a chemical vapor deposition (CVD) technique, act as elastic springs, and a metal coating on the probes is used for increased electrical conduction. This design and architecture presents a scalable approach where thousands of probes can be fabricated in very short production times. 1.5 Ohm resistance and reliable performance for 6000 cycles at 50 [mu]m over-travel was achieved for a column of 200 [mu]m x 200[mu]m cross-section and 1plm of Au deposition. In-situ scanning electron microscope mechanical compression tests revealed a unique deformation mechanism of the CNT structures where continued compression results in successive buckle formation which later can serve as micro-bellows and elastic springs.<br>(cont.) A novel stiffness tuning method is presented to control the elastic properties of a given CNT probe by controlling the initial compressing amount. Further stiffness tuning is achieved by changing gas composition during CVD growth where CNT diameter and density is modified. Lateral compression and densification tests show that these CNT structures are highly anisotropic and have very different deformation mechanisms in vertical and lateral directions. Mechanical properties resulting from two main CVD growth techniques, namely fixed catalyst where a thin film of catalyst layer is deposited onto the growth substrate, and floating catalyst where the catalyst particles are introduced in the gas phase, are compared. It is found that floating catalyst CVD growth yields much stiffer structures due to the relatively larger CNT diameters. As the adhesion of CNT structures to the growth substrate is very weak and the support layer is typically an insulator, a versatile transfer printing technique is developed which enables simultaneous placement and reinforcement of the probes on a wide range of substrates, including metals and printed circuit boards. Electromechanical performance and failure mechanisms of fully functional metal-CNT hybrid probes are presented.<br>by Onnik Yaglioglu.<br>Ph.D.

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44

Rangharajan, Kaushik Krishna. "Engineering Electromechanical Systems to Regulate Nanoscale Flows." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1524140747281763.

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45

Wilhelm, Eric Jamesson 1977. "Printed electronics and micro-electromechanical systems." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/27141.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2004.<br>Includes bibliographical references.<br>Current electronics and micro-electromechanical systems (MEMS) manufacture is optimized for the production of very high-volume parts on a limited range of substrates. These processes are long, consume large amounts of resources, and require expensive machines and facilities, but yield excellent products. Cheaper, faster printing processes are beginning to emerge with the ability to economically produce low or high-volume electronics and MEMS on flexible substrates. This thesis describes the theoretical and practical design of a suite of printing processes including liquid embossing and offset liquid embossing (OLE). These printing techniques have created resistors, capacitors, and thin-film transistors without etching, vacuum deposition, or high temperatures. Here, the fabrication of all-printed electrostatic actuators is described In liquid embossing a polydimethylsiloxane (PDMS) stamp with bas-relief features is brought into intimate contact with a thin liquid film such as a metal or semi-conductor nanoparticle colloid, spin-on-glass, or polymer to create patterns as small as 100 nm. A simulation of liquid embossing was developed by coupling fluid flow in a thin liquid film to the diffusion of solvent into a PDMS stamp. The model accurately predicts real aspects of the printing process including the time required to stamp and usable stamp geometries. OLE was designed to address some of the limitations of liquid embossing. In OLE the patterned liquid film is transferred to a different substrate, allowing finer control over geometry and material placement and leaving behind excess material trapped during stamping. All-printed electrostatic actuators were fabricated using OLE by patterning gold on flexible polyimide and then under-etching with oxygen plasma.<br>The polyimide acts as a sacrificial material, dielectric layer, and mechanical substrate. Square electrostatic actuators 50 microns on a side can modulate light up to approximately 1 kHz with fields of 1-2 volts per micron. These actuators also show a sharp non-linear response to driving voltage that could be used as part of a passive row-column addressing scheme.<br>by Eric Jamesson Wilhelm.<br>Ph.D.

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46

Zhang, Xu. "Implicitly-coupled electromechanical and electromagnetic transient analysis." Thesis, Illinois Institute of Technology, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3664035.

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<p> The operation of an electrical power system involves continuous electromechanical and electromagnetic interaction of energy among the system components. Under normal operation, the system behavior could be represented by voltage and current phasors in the frequency domain. However, the system may not work on the fundamental frequency following some fast transients (loss of generator, switching event, system disturbance and etc.), at this time we need specific tools to investigate the dynamic scenario.</p><p> Transient stability (TS) simulator, also referred to as electromechanical transient simulator, running at time steps on the order of milliseconds and only capable of capturing the fundamental frequency transient, is used for the analysis of large-scale networks. On the other hand the electromagnetic transient (EMT) simulator running at time steps on the order of microseconds, with detailed equipment modeling is capable of analyzing transients over a wider frequency spectrum; however, it is computationally onerous, so it is typically restricted to the analysis of small networks.</p><p> An electromechanical-electromagnetic transient simulator is the combination of a TS simulator and an EMT simulator, inheriting the merits of both programs The basic idea of an electromechanical-electromagnetic simulator is to decompose the power system into two broad categories: a large connected TS network (main network) and smaller EMT network (detailed subsystem). The main network is running on TS simulator while the detailed subsystem is running on the EMT simulator. The implicitly-coupled electromechanical and electromagnetic simulator has TS and EMT simulators coupled at the equation solution level, which could ensure the consistence of the solution between TS and EMT simulation.</p><p> Instead of using fundamental frequency equivalent model of the main network in EMT simulation of implicitly-coupled electromechanical and electromagnetic simulator, a frequency dependent network equivalent (FDNE) model is utilized to preserve the non-fundamental frequency fast transient response of the main network.</p><p> Along with the implementation of FDNE model, this research work also propose a new TS simulator that is capable of running three-phase transient stability simulation under fundamental and non-fundamental frequency simultaneously. Furthermore the performance of implicitly-coupled electromechanical-electromagnetic transient simulator could be improved with the implementation of this new TS simulator.</p>

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47

Spencer, Matthew Edmund. "Design Considerations for Nano-Electromechanical Relay Circuits." Thesis, University of California, Berkeley, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3733438.

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<p> Complementary metal oxide semiconductor (CMOS) technology has a minimum energy per operation, and that limitation is one of the myriad hurdles CMOS faces as it reaches small scales. This minimum energy is set by the balance between leakage energy and dynamic energy in subthreshold CMOS circuits, and sets floors on the achievable energy of digital units. A new, post-CMOS device with a sharper subthreshold slope than CMOS would be able to sidestep this minimum energy constraint. </p><p> A candidate device called a nano-electromechancial (NEM) relay has recently emerged. NEM relays are small, integrated, capacitively-actuated, mechanical switches. The devices have demonstrated extremely high subthreshold slopes: ten orders of magnitude over a millivolt of swing. However, in the same lithographic process they are twenty times larger than a minimum sized CMOS device, their gate capacitance is ten times that of a minimum sized CMOS device, and their mechanical motion is an order of magnitude slower than a CMOS inverter. Can NEM relays improve digital systems even with these drawbacks? </p><p> With proper circuit design, simulations say "yes". This dissertation examines three of the critical components of digital systems—logic, timing, and memory—and proposes NEM circuits which mitigate the weaknesses of the technology while achieving design goals. Simulations show that optimized relay logic, which arranges for all of the slow movement of relays to happen at the same time, can achieve an improvement of 10x in energy-per-operation below the CMOS minimum energy point at a penalty of 10x in delay and 3x in area. This logic style is experimentally demonstrated. In addition, relay latch based timing with staticization in the feedback path is simulated, which results in a working relay pipeline with zero mechanical delays of timing overhead. Finally, a new device called NEMory is proposed to build dense, non-volatile, mechanical memory. A hybrid NEMory/CMOS array is simulated, and its performance is compared to other memory solutions. The NEMory density is higher than any non-volatile memory except for multi-level cell, o-chip Flash, and its read and write energy are lower than any other non-volatile technology. Finally, the scaling and process limits of realizing mechanical devices are discussed in the context of future work.</p>

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48

Calbry-Muzyka, Adelaide S. "Technical development of an electromechanical braille labeler." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/54527.

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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2009.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (p. 36-37).<br>The work presented in this thesis concerns the development of an electromechanical device that prints labels in braille. For blind and visually impaired people, differentiating between similarly-shaped objects - CDs, medication bottles, food cans, etc. - is a challenge that can be solved by affixing braille labels to the surface of these items. However, the existing technology for making braille labels is either fully manual and slow, or too large to be portable. As a result of this identified need, the first prototype of a braille labeler was developed in the fall of 2008. However, several outstanding mechanical and design issues remained. During this thesis, the first prototype was tested with focus groups to identify these issues. These included the lack of a cutting mechanism for the tape, the uncomfortable shape and size of the device, and the ease of manufacturing of some components. A second prototype was designed and built, resolving these problems.<br>by Adelaide S. Calbry-Muzyka.<br>S.B.

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49

Bryant, Reginald (Reginald Eugene) 1978. "High-index-contrast electromechanical optical switches." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/65998.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, June 2011.<br>"June 2011." Cataloged from PDF version of thesis.<br>Includes bibliographical references (p. 278-288).<br>System developers are looking to replace protocol-dependent, bandwidth-limited optical networks with intelligent optically-transparent integrated photonic networks. Several electromechanical optical switches are explored with the intent of being utilized as optical switching elements in transparent, integrated photonic networks. The electromechanical optical switches are based on high-index-contrast waveguide optics that is integrated with electrostatic parallel plate actuators on submicron scales. High-index-contrast waveguides are attractive due to their reduced bending radius and low in-plane scattering and optical loss. These qualities of high-index-contrast waveguides make them uniquely suited for low-cost, large-scale integration. The parallel plate actuators are used to control the waveguide light switching by mechanically establishing and terminating light pathways on time scales well below 100s of microseconds. Investigations of light pathway coupling schemes and parallel plate actuator configurations led to the development of several device structures that are categorized in three distinct device generations. Design premiums were placed upon device footprint minimization, polarization independence, high extinction ratios, and operational robustness.<br>by Reginald Eugene Bryant.<br>Ph.D.

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50

Wang, Jin. "Computational study of electromechanical instabilities in dielectric elastomers." Thesis, Boston University, 2014. https://hdl.handle.net/2144/21271.

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Thesis (M.Sc.Eng.)<br>Dielectric elastomers (DEs) have attracted significant attention in recent years and have been found to provide excellent overall performance in actuation-based application. This thesis will introduce the fundamentals of DEs, derive the field and finite element equations for simulating its deformation, and then focus on numerically studying electromechanical instabilities, in particular electrostatically driven creep and the effect of pre-stretch on surface (creasing) instabilities. First, a nonlinear, dynamic finite element model coupled with a finite deformation viscoelastic constitutive law is utilized to study the inhomogeneous deformation and instabilities resulting from the application of a constant voltage to dielectric elastomers. Theoretical studies are performed of two problems that have been experimentally observed, i.e. electromechanical snap-through instability and bursting drops in a dielectric elastomer. In general, increasing the viscoelastic relaxation time leads to an increase in time needed to nucleate the electromechanical instability. However, it is found that the time needed to nucleate the instability of these two cases scales with the relaxation time. Second, the effect of pre-stretch on the performance of dielectric elastomers is studied. Two cases are studied, the electromechanical snap-through instability under equibiaxial pre-stress, and a strip under uniaxial pre-stretch. It is found that prestress markedly increases the stability of the elastomers, while pre-stretch increases the critical field for electro-creasing instability.<br>2031-01-01

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