• Proceedings of the KIEE Conference
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• 2008.04a
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• pp.199-200
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• 2008

Demand for reliability and safety in modem systems has been increased in the research on fault detection and isolation. At traditional approaches to fault detection, redundant sensors have been used. More advanced methods are the residual analysis of signals which are created by the comparison between the actual plant behavior and the output response of a mathematical model. However, mathematical system models are difficult to obtain by using physical laws. These problems can be solved by system identification. In this paper, the transfer function of a direct current motor is estimated by using the system identification. And, the efficiency of the fault detector design is verified by using experiments.

• Journal of Advanced Marine Engineering and Technology
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• v.37 no.8
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• pp.905-910
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• 2013

The flow analysis has been made by applying the turbulent models in the helically coiled tubes of heat transfer. The k-${\varepsilon}$ and Spalart-Allmaras turbulent models are used in which the structured grid is applied for the simulation. The velocity vector, the pressure contour, the change of residuals along the iteration number and the friction factors are simulated by solving the Navier-Stokes equations to make clear the Reynolds number effect. The helical tube increases the centrifugal forces by which the wall shear stress become larger on the outer side of the tube. The centrifugal force makes the heat transfer rate locally larger due to the increase of the flow energy, which finds out the close relationship between the pressure drop and friction factor in the internal flow. The present numerical results are compared with others, for example, in the value of friction factor for validation.

• Journal of the Korean Institute of Landscape Architecture
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• v.24 no.3
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• pp.133-149
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• 1996

The aim of this study is to compare open space planning between Australia and Korea by Local Governments Areas. Open space planning is carried out at the state and municipal level in Australia, but by metropolitan city government in Korea. This study is structured by reviewing the presemt phenomena of provision of open space in Sydney and Seoul, By measuring disparity in terms of open spaces by L. G. A. s an by comparing planning approaches between two cities, for example policy, government standards, government administration system in open space management. In this paper, the provision of parks in Sydney and Seoul are comparatively examined and geographically mapped, and multiple repression analysis is applied to measure the residuals from the line of equality. The results of this study show that, 1) During the last 1 dacade from '80 and '90. Sydney has increased the quantity of open spaces from ratio of 19.11ha/1000 to 22.33ha/1000 of parks, however Seoul decreased it by the ratio of 12.21$m^2$/person to 1012$m^2$ per person. 2) Sydney has more programs, such as Greenspace program, Metropolitan open space program etc. to increase and to distribute open spaces equally rather than Seoul which has less open spaces. 3) There exists patterned inequality in terms of open space provision in inner city and suburb between Sydney and Seoul. 4) Seoul requires more active polices to increase open spaces like Greenacre Program of New Jerrsey State, Double Open Space Pland of Tokyo or Green Space Program of Sydney.