• The Transactions of the Korean Institute of Electrical Engineers B
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• v.55 no.8
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• pp.408-415
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• 2006

This paper deal with control and design of 50,000rpm class Active Magnetic Bearing(AMB) system for high speed precision motor. In the design of AMB system, the design parameters adopted high robust rotor shaft, Active Magnetic Bearing, sensor and control system. In the design of Magnetic Bearing, 2-D Finite Element Method(FEM) is used and transfer matrix method is using for rotor dynamics. The control accuracy of high speed AMB system is demonstrated by experimentations.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2006.03a
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• pp.401-408
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• 2006

An optimum design method for hybrid control systems is proposed in this study. By considering both active and passive control systems as a combined or a hybrid system, the optimization of the hybrid system can be achieved simultaneously. In the proposed approach, we consider design parameters of active control devices and the elements of the feedback gain matrix as design variables for the active control system. Required quantity of the added dampers are also treated as design variables for the passive control system. In the proposed method, the cost of both active and passive control devices, the required control efforts and dynamic responses of a target structure are selected as objective functions to be minimized. To effectively address the multi-objective optimization problem, we adopt a preference-based optimization model and apply a genetic algorithm as a numerical searching technique. As an example to verify the validity of the proposed optimization technique, a wind-excited 20-storey building with hybrid control systems is used and the results are presented.

• Proceedings of the IEEK Conference
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• 2003.07c
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• pp.2509-2512
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• 2003

The active magnetic bearing(AMB) has statey-state error of the displacement by the external force. This paper presents a PID controller design using LQR method in the active magnetic bearing to compensate for the displacement by the external force.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.10 no.5
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• pp.672-679
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• 1999

This paper describes the design method of active bandpass filters which employ active impedance inverters. Several authors have reported active bandpass filters. However, the functional description of the active blocks in the filters have not been throughly studied. In this paper, the active inverter block of the bandpass filter has is analyzed in the view point of filter design. The designed 3-pole bandwidth filter has its insertion gain of 24 dB at the center frequency of 865 MHz with 75 MHz bandwidth. The noise figure of the active bandpass filter is less than 2.5 dB within its passband.

• Journal of the Korean Society of Systems Engineering
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• v.17 no.1
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• pp.1-10
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• 2021

In this paper we proposed the alternative analysis of reliability design using redundancy technique. First, we presented the process for establishing the reliability design alternative analysis process considering the active redundancy and the standby redundancy. and then, the case analysis of A driving equipment was performed in accordance with the reliability design alternative analysis process presented. In case the series reliability design result is not met with the reliability target value. so, the target item for redundancy design of A driving equipment were selected as items with a severity of two or higher. The redundancy design applied with active and standby redundancy techniques were analyzed using BlockSim software. As a result, it was analyzed that reliability design to active redundancy with one of two elements required for A driving equipment is the most efficient compared to the target value of reliability. The results of this study can be usefully used before the reliability design is performed.

• Journal of the Korea Society of Computer and Information
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• v.12 no.2 s.46
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• pp.325-331
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• 2007

This paper proposed modelling and design method in suspension system design to analyze active suspension equipment by adopting active robust control theory. Recent in the field of suspension system design it is general to adopt active control scheme for stiffness and damping, and connection with other vehicle stability control equipment is also intricate, it is required for control system scheme to design more robust, higher response and precision control equipment. It is known that active suspension system is better than passive spring-damper system in designing suspension equipment. We analyze suspension system with considering location of front-rear wheel and driving velocity, then design control system. Numerical example is shown for validity of robust control system design in active suspension system.

• Journal of the Korean Society of Safety
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• v.32 no.6
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• pp.81-88
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• 2017

This study deals with the optimal design of a hybrid control system composed of a combination of active control system and passive control system for effective seismic performance improvement of two adjacent structures. The proposed hybrid control system adopts a configuration of installing an active control device in one building and connecting two adjacent structures with a passive control device so that the one-side active control force can be bi-directionally applied to both buildings through the passive connecting devices. In order to derive the optimal performance of the proposed system, the design parameters of the passive and active control systems were searched using the genetic algorithm. Numerical simulations of 10-story and 8-story buildings have been performed to verify the effectiveness of the proposed technique. For the purpose of comparison, the conventional independent control system with two identical active control systems being installed separately for each structure was also optimally designed and its seismic response has been evaluated as well. From the comparative results of the two control systems, it is demonstrated that the proposed hybrid control system requires larger control force for its one-side active control device than the conventional independent control system does for each of both-side active devices, but quite less than the total control force required for both-side devices of the independent control system, while maintaining similar seismic performance. Therefore, the proposed system is more economical and reliable than the conventional independent control system with two identical active devices.

• Journal of the Korea Fashion and Costume Design Association
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• v.10 no.3
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• pp.47-59
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• 2008

The recent trend of Sports Wear is seeking functionality and fashion at the same time, where the spread of sportism becomes caual style leading street fashion. Sports Wear is classified into active Sports Wear and Sports casual Wear, in which active Sports Wear is expanded to a mixture with Sports casual wear. The purpose of this study is to research the trend of materials used in active Sports Wear and Sports casual wear. Materials used for jacket/jumper, pants and t-shirts of active Sports Wear and Sports casual wear, and high-tech functional materials used for active Sports Wear have been analyzed. The results of the study are the following: a) Most of the materials used for Sports Wear are polyester, nylon, cotton, and a mixture of cotton and polyester. Active Sports Wear uses functional materials and texture such as Dri-Fit, which absorbs and dries fast, whereas Sports casual wear satin, cire and denim has been used to keep up with the trend rather than focusing in functionality: b) companies such as Nike and Adidas have used many high-tech materials to emphasize the functionality of Sports Wear, while Puma stresses on fashion rather than function, however uses spandex in order for the consumer to feel comfortable during physical activities; c) active Sports Wear in jacket/jumper, pants and t-shirts uses functional material and texture, however Sports casual wear uses satin and cire to keep up with the fashion trend rather than functionality; d) and Nike uses high-tech funtional materials for its Sports Wear in therma-fit, Clima-fit, Dri-fit and storm-fit, whereas Adidas uses Clirna-lite, Clirna-proof, Clima-warm, and Clirna-cool in their active Sports Wear.

• Proceedings of the Korea Database Society Conference
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• 1999.06a
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• pp.95-102
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• 1999

The web-based group collaborative systems are emerging as enterprise-wide information systems. Since data in group collaborative systems are apt to be shared among multiple concurrent users and modified simutaneously by them, the web-based group collaborative systems must support synchronous collaboration in order to provide users with synchronized and consistent views of shared data. This Paper proposes an active web server which can facilitate synchronous collaboration in web-based group collaborative systems. To accomplish such a goal, the active web server manages dependency relationships between shared data and web browsers referencing them and actively propagates changing details of the shared data to all web browsers referencing them. And, this paper examines usefullness and effectiveness of the active web server to apply it to the ball-bearing design example of concurrent engineering design systems. The prototype system of the active web server is developed on a commercial Object-oriented Database Management System (ODBMS) called OBJECTSTORE using the C＋＋ programming language.

• Journal of Korea Multimedia Society
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• v.6 no.7
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• pp.1245-1255
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• 2003

Request for network becomes complicated gradually and network traffic is increasing, To overcome this situation, the structure of network node should be changed to accept new service quickly and economically by executing program code in node itself. Active Network's research can use net resources more properly because of executing program within node itself. In this paper, we design a programming language, namely ASL, for Active Sensor to describe function and behavior of active sensor. We also design and implement the interpreter for proposed ASL.