• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.7 no.1
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• pp.112-119
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• 1995

Measurements of the local heat transfer coeffcients on a spherically concave surface with a round impinging jet are presented. The liquid crystal transient method was used for these measurements. This method, which is a variation on the transient method, suddenly exposes a preheated wall to an impinging jet while video recording the response of liquid crystals for the measurement of the surface temperature. The Reynolds numbers used were 1,000, 23,000 and 50,000 and the nozzle-to-jet distance was L/d=2, 4, 6, 8, 10. Presented results are compared to previous measurements for flat plate. In the experiment, the local heat transfer Nusselt numbers on a concave surface are higher than those on a flat plate. Maximum Nusselt number at all region occured at L/d=6 and second maximum in the Nusselt number occured at R/d=2 for both Re=50,000 and Re=23,000 in case of L/d=2 and for only Re=50,000 in case of L/d=4. All other cases exhibit monotonically decreasing value of the Nusselt number along the curved surface.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1994.04a
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• pp.89-94
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• 1994

Latticed domes take form a curved surface by arranged members with certain patterns. For this reason, it is possible for the characteristics of vibration to complicate by change of various parameters of dome; grid-pattern, boundary condition and ratio of radius-height etc. Therefore, it is important to clarify the effect by these parameters before generalized dynamic response analysis. So this study deals with free vibration analysis of latticed domes and makes clear an effect of shape coefficient, that is, geometrical characteristics of latticed domes, on the vibration characteristics.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.593-594
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• 2013

• Transactions of the Korean Society of Mechanical Engineers
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• v.2 no.2
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• pp.38-41
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• 1978

이 논문에서는 표면의 일부에 기지의 압력을 밥는 긴 원주내의 응력분포를 구하는 문제를 고찰하였다. 문제를 혼합경계치조건에서 발생되는 쌍적분방정식의 해를 구하는 문제로 간단히 한후에 제 2종 Fredholm 적분방정식을 해결하는 문제로 하였다. 이 적분방정식의 수직해를 전자계산기에 의하여 구한 다음 도시하였다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.10a
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• pp.461-462
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• 2006

• Communications for Statistical Applications and Methods
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• v.16 no.5
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• pp.881-889
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• 2009

Support vector machines(SVMs) are known as flexible and efficient classifier of multivariate observations, producing a hyperplane or hyperdimensional curved surface in multidimensional feature space that best separates training samples by known groups. As various methodological extensions are made for SVM classifiers in recent years, it becomes more difficult to understand the constructed model intuitively. The aim of this paper is to visualize various SVM classifications tuned by several parameters in reduced dimensions, so that data analysts secure the tangible image of the products that the machine made.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 1992.08a
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• pp.140-145
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• 1992

The design of large offshore structures and their operations depend critically upon the wave-induced loads and motions. Thus, over the last two decades, substantial efforts have been devoted to the development of various principles and methods which can provide these predictions in a reliable and efficient manner.(omitted)

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1994.10a
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• pp.108-112
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• 1994

The paper describes the effects of magnetic field on the electrochemical polishing process in the view of ionic in the electrolyte. Theoretical background was suggested how magnetic field increases the material removal efficiency and surface finishing ability Magnetic field changes the jonic movement in the electrolyte from linear motion to curved or complex oscillating one, thus increases the electrolytic current density and, as the results, the finishing efficiency.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1994.10a
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• pp.676-680
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• 1994

Recently the needs for the experts who can solve the complex problem arising at the special areas are continuously increasing in our social life. So many researchers have studied about the expert systems as a part of an artificial intelligence during last two decades. This study was carried out in order to develope an expert system, ESSM, for the NC data generation to machine the curved surface of a forming die to fabricate the shadow mask of TV Brown Tube.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2002.05a
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• pp.62-65
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• 2002

A dieless forming system which consists of hydraulic punch elements and elastomer/fluid pads, was developed for sheet metal forming. 2-D curved surface forming was carried out using open-loop, closed-loop, and repeated forming method. Closed-loop exhibited higher decision than open-loop forming. Repeated forming also showed reduced spring back and possibility of high precision.