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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.
101

Design, Fabrication and Control of a Magnetic Capsule Robot for the Human Esophagus

Hosseini, Saman 18 February 2010 (has links)
Biomedical engineering is the application of engineering principles and techniques to the medical field. It combines the design and problem solving skills of engineering with medical and biological sciences to improve healthcare diagnosis and treatment. As the result of improvements in robotics and micro technology science in the 20th century, micro electromechanical system technology has joined with medical applications which results in micro robotic medical applications. Drug delivery is one of the most important and controversial topics which scientists and engineers have tried to improve in medical applications. For diseases like cancer, localized drug delivery is a highlight target involving bombarding a small area of a human’s body and this technology has not been completely achieved yet. The ultimate objective of this thesis is the development of wireless capsule robot controlled by a magnetic drive unit. A magnetic drive unit is a system that consists of electromagnets, which produce the magnetic field from outside of the patient’s body. The capsule robot, which is the slave robot in the system, moves inside a human’s gastrointestinal tract. This project is focused mainly on a human esophagus and all the experiments are done in a prototype of the human’s esophagus. Drug delivery for diseases like cancer is the objective of the capsule robot. The proposed design consists of a slave permanent magnet for the motion of capsule robot in a tube, a reservoir of drug, and a micro mechanical mechanism for drug release. The capsule robot is fabricated and developed in a 12mm length and 5mm diameter with the weight of 1.78 grams without the built-in permanent magnet. The drug delivery system is a semi-magnetized system, which can be controlled by an external magnetic field. It consists of a mechanical plunger and spring, which can be open and close through an external magnetic field manipulation. The amount of drug for a desired location can be controlled by manipulating the external magnetic field. To achieve this target, analytical modeling is conducted. A numerical simulation and an experimental setup demonstrate that a capsule robot in a human esophagus in a simple and multi channel system. Horizontal control is set for the capsule robot, using a custom-designed controller and a colored liquid is released with the external magnetic field. The present study with its fabricated prototype is a research is this area to prove the concept of wireless control of a robot inside a human body and the potential for a drug delivery system. It is expected that the results achieved in this project will help realize and promote capsule robot for medical treatments.
102

Tang before Tang Dynasty Taoism policy and Taoism control system research

Hsu, Li-chang 22 July 2010 (has links)
none
103

Active Reflection Absorption for a Three Dimensional Multidirectional Wave Generator

Cruz Castro, Oscar 2009 August 1900 (has links)
In order to implement an accurate system that allows for absorption of reflected waves impinging to a wave maker (Active Reflection Absorption), it was required to apply a method to estimate properly the direction of arrival of the waves that does it in the fastest way possible. Our wavemaker control system has been prepared to handle an algorithm provided by Bosch-Rexroth where the wave angle estimation is practically locked to a very narrow frequency band (spatial gain-mixer). The system was evaluated with physical tests in a 3D wave basin for different conditions of reflected waves arriving with an angle to the wavemaker front, and acceptable performance has been found for the 3D ARA mode. However, for certain conditions over-compensation or sub-compensation can develop resulting in a poor absorption. This is mainly related to not being able to determine accurately the direction from which the reflected waves travel towards the wavemaker. The present work employed concepts found in the areas of antenna array signal processing and signal propagation, which were applied to this problem. This approach coupled naturally with our wavemaker system since it was prepared with 48 gages that can be employed in an array antenna fashion. A program was codified from an algorithm found in literature to calculate the Direction of Arrival (DOA) of the reflected waves. The focus for the testing of this program was with regular waves. The tests were conducted to validate the program with different angles of incidence and show that for regular waves the program was able to detect accurately the DOA of these in as few as 5 snapshots, with a minimum of 7 gages used as the antenna input. With data obtained directly from the control system of our wavemaker using regular waves, the program was able to determine the DOA. The computational burden of the algorithm is not significant in the case of regular waves. A modification of the program is required to analyze the DOA of reflected irregular waves, which could increase the computational burden. Actual implementation of this program to our control system depends on cooperation with Bosch-Rexroth.
104

Robustness of Ethernet-Based Real-Time Networked Control System with Multi-Level Client/Server Architecture

Bibinagar, Naveen Kumar 2010 August 1900 (has links)
The importance of real-time communication at the device level in a factory automation setup is a widely researched area. This research is an effort to experimentally verify if Ethernet can be used as a real-time communication standard in a factory automation setup, by observing the effects of packet delays, packet loss, and network congestion on the performance of a networked control system (NCS). The NCS experimental setup used in this research involves real-time feedback control of multiple plants like DC motors and a magnetic-levitation system connected to one or more controllers. A multi-client-multi-server architecture on a local area network (LAN) was developed using user datagram protocol (UDP) as the communication protocol. Key observations are as follows. (1) The multi-client-single-server system showed the highest packet delays compared to single-client-single-server architecture. (2) In the singleclient- single-server system, as the Ethernet link utilization increased beyond 82 percent, the average packet delays and steady-state error of the DC motor speed-control system increased by 2231 percent and 304 percent, respectively. (3) Even under high link utilization, adding an additional server to the NCS reduced average packet delays considerably. (4) With large packet sizes, higher packet rates were automatically throttled by Ethernet’s flow control mechanism affecting the real-time communication negatively. (5) In the multiclient- multi-server architecture, average packet delays at higher packet rates, and at higher packet lengths were found to be 40 percent lesser than the those of the single-clientsingle- server system and 87.5 percent lesser than those of the multi-client-single-server system.
105

Integration and Application of the Embedded System and the World-Wide Web

Li, Yiing-jui 13 August 2004 (has links)
In recent years, the requirement for embedded controllers has been steadily on the increase due to the development of computers, communication ,WWW and consumers¡¦ products. Consequently, integration and application of the embedded system and the World-Wide Web become more and more important. The Web-based embedded system developed in this paper tends build a service of micro web server. By this service, users can not only receive the information from the system via the browser, but also design particular processes for themselves. Besides, the system developer can use the most popular tools to edit the page for the Web-based embedded system. This Web service technology offers an operational interface, which is user-friendly, and cost effective with the capability of cross-platform and TCP/IP transmission. The presented achievement is applied to temperature control system for performance evaluation of remote control.
106

Computer Simulation and Design Analysis of Smoke Management System In Large Stations

Ke, Jian-Ming 17 June 2003 (has links)
In recent year, there were many fire accidents in MRT and subway station,due to faolure in smoke control system and emergency operation strategies. The goal of this project is to use two sofeware¡XFDS and Star-CD to simulate the fire in MRT station and predict the height of smoke layer and its descending rate .The comparison of the two indicated sucessful result can be obtained with deviations within engineering tolerance..
107

Applications of Lie Group on Linearization to Nonlinear Control System

Liu, Sheng-Yi 23 July 2003 (has links)
This paper presents the Lie-Backlund symmetry method to give the equivalence between differential equations and describe the equivalent transformation procedure of nonlinear control systems of partial differential equations. The equivalent linear systems found by solving the infinitesimal generator of one-parameter Lie groups with prolongations and the infinitesimal generator are used to construct the parameters of invertible mapping u. And the equivalence linear form of the nonlinear system is constructed via u. Some necessary conditions for mapping a nonlinear control system of PDE¡¦s to a linear control system of PDE¡¦s are discussed, and application of Lie-Backlund symmetries and invertible mapping u constructed linear time-invariant control system of partial differential equations.
108

A Study of Information Security for Computerized Process Control

Chen, Pao-Tien 12 June 2008 (has links)
In manufacturing industrial, for example, petrochemical plant, the promotion of technology makes manufacturing process computerization to be possible. The systems which control the manufacturing process are called Process Control System. Enterprises introduce the projects of process improvement to reduce the operation cost and enhance the product quality. It is necessary to have comprehensive information and technology to support the success of project for process improvement. Thus, it is a trend to setup the connections among Process Control Network, Process Information Network and Intranet. Due to the connections among networks, Process Control System is facing the threats of computer viruses, worms, attackers, and other malicious codes. Process Control System controls the manufacturing process base on the instructions issued from operators to maintain plant operations in a safe condition. Process Control System is the kernel of process operations. If Process Control System is being attacked or infected by computer viruses, the impacts would be the disclosure of critical business information, the failure of servers/workstations for monitoring process, or Process Control System fails totally that result in the plant operations with risky. The worst case would be an incident about pollution of environment, explosion, properties destroyed, or life lost. Therefore, enterprise should focus on reinforcing the information security mechanism of Process Control System to ensure plant operations reliably and safely. The objectives of this study are: a) To realize the challenges and threats that Process Control System is facing by the way of literature review. b) To discuss information security management related issues and resolutions of Process Control System base on physical, network, and servers respectively. c) To discuss the efficiency of the model of information security management that has been implemented in the enterprise. d) To make this study as a reference for related industries.
109

Design and Application of the Management Control Systems in the Information Services Industry - A Case of a Big Company's Taiwan subsidiary.

Chang, Kun-yu 28 August 2009 (has links)
The information service industry keeps growing up in Taiwan in recent years. Many local companies of information service follow this trend as well. Management Control System (MCS) is one of the most important factors to make organization grow stably when it develops from star stage to mature stage. So that this research adopts the approach of case study to interview four vice presidents, who are in charge of four different departments in the case company that is leading in information service industry. This research intends to analyze the characteristics of MCS of the case company through deep exploratory case study. Then it will discuss over the differentiation between literature review and real interview. Finally, this research will propose conclusions and suggestions to the domestic companies that want to design and implement MCS. This research analyzes the characteristics of MCS by degree of formalization, participation, communication and information sophistication. The objectives of this research are as follows: 1¡BTo comprehend the characteristics of MCS of information service industry. 2¡BTo compare the difference between different departments in case company. 3¡BTo analyze the relationship between MCS and organization life cycle. The conclusion shows information service industry that belongs to Professional Service can also adopt bureaucratic MCS which is like Mass Service. It depends on the task whether can be identify cleanly. Key Words: management control system, information service industry, scorecard, organization life cycle.
110

Design of a Quay Crane Training Simulator

Chen, Boyang, Xu, Mingyi January 2015 (has links)
No description available.

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