• Journal of the Korean Operations Research and Management Science Society
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• v.27 no.4
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• pp.41-65
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• 2002

We study a multi-component production/inventory system in which individual components are made to meet various demand types. We assume that the demands arrive according to a Poisson process, but there is a fixed probability that a demand requests a particular kit of different components. Each component is produced by a flow line with several stations in which the processing times of each station follow a two-stage Coxian distribution. The production of each component is operated by an independent base-stock policy with blocking. We assume that the time needed to assemble final products follows a general distribution and the capacity of an assembling facility is sufficiently large. The objective of this study is to obtain key performance measures such as the distribution of the number of each orders for each final product and the mean time of fulfilling a customer order. The basic principle of the proposed approximation method is to decompose the original system into a set of subsystems, each subsystem being associated with a flow line. Each subsystem is analyzed in isolation using a Marie's method. An iterative procedure is then used to determine the unknown parameters of each subsystem. Numerical results show that the accuracy of the approximation method is acceptable.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.476-480
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• 2003

This paper presents an effective method to analyze the dynamic characteristics for the shilling transients of power transmission system using the multibody dynamics, which is composed of subsystem equation, subsystem assemble, and the self-determining technique for the system degree of freedom. Using the advantages of multibody dynamics, the proposed method can be used easily for mathematical models of mechanical systems, such as a power transmission, compared with newtonian method. With this theory, dynamic simulation program was developed. The program can be used to verify system performances, transient phenomena, and other dynamic problems. The simulation of a target system was presented, and its validity was attained by being compared with the previous analysis using newtonian method.

• 한국초전도학회:학술대회논문집
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• v.10
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• pp.35-39
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• 2000

Large-area high-temperature superconducting (HTS) films, filter design and damage-free processing technique have been developed to fabricate low insertion loss and sharp skirt filters. Further, long life cryocooler, low temperature low noise amplifier (LNA) and cryocable have been developed to assemble HTS filter subsystem for IS-95 and IMT-2000 mobile telecommunication. The surface resistance of the films was about 0.2 milli-ohm at 70 K, 12 GHz. An 11-pole HTS filter for IS-95 telecommunication system and a 16-pole HTS filter for IMT-2000 telecommunication system were designed and fabricated using 60 {\times}$ 50 mm$^2$ and one half of 3-inch diameter YBCO films on a 0.5-mm-thick MgO substrate, respectively. We have assembled the filter and low temperature LNA in a dewar with the cryocooler. Ultra low-noise (noise figure: 0.5 dB at 70 K) and ultra sharp-skirt (40 dB/1.5 MHz) performance was presented by the IS-95 filter subsystem and the IMT-2000 filter subsystem, respectively.

• Proceedings of the KSR Conference
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• 1999.11a
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• pp.202-208
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• 1999

Train system like high speed train is assemble by a number of subsystem. Therefore, the Integration of train system needs the process that investigates the interface and influence between subsystems. In this paper, It studied the Design & Integration and major process of Korea High Speed Tram Project,

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.6
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• pp.175-181
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• 2004

This paper presents the main method to analyze the dynamic characteristics of power transmission system using the multi-body dynamics, which is based on the concept of subsystem equation, subsystem assembling, and the self-determination technique for the system degree of freedom. We can model the mechanical components of power transmission system easily with the advantage of multi-body dynamics. Based on the theory, a dynamic simulation program was developed to analyze system performances, transient phenomena, and other dynamic problems. The driving performance of automatic transmission was simulated with using the multi-body dynamics and Newtonian method, and the validity of program was proved by comparing the two kinds of result.