• 한국전산유체공학회:학술대회논문집
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• 2008.03a
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• pp.118-124
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• 2008

The characteristics of heat transfer in a two-dimensional channel obstructed by a square rod is investigated by a turbulence model. The computation is made for the six cases of different rod positions between channel walls. To analyze the wall heat transfer, the heat flux of channel walls is set as a constant value and the $k-{\epsilon}-f_{\mu}$ model is employed. Downstream the square rod, the flow recirculation region appear and they are varied by the rod position. The enhancement of the turbulent heat transfer to the wall is induced by the flow instability using a square rod. The averaged heat transfer rate is maximized at a specific rod position. Finally, the effects of square rod on unsteady flows are scrutinized with the frequency analysis.

• Proceedings of the KSME Conference
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• 2000.11b
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• pp.272-277
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• 2000

The heat transfer characteristics of confined turbulent slot jet impingement on the flat plate with square rods(turbulence promoter) have been experimentally investigated at different nozzle configuration. The effects of jet Reynolds number (Re=3900, 5800, 7800, 9700), dimensionless slot-to-plate distance(H/B=4, 6, 8) and clearance(c) between square rods and the plate were examined. Measurement of heat transfer rate were conducted using naphthalene sublimation technique. When square rods were inserted over the heat transfer surface, heat transfer rate was slightly increased in the wall jet region and the sharp-edged orifice nozzle was heigher than squared orifice nozzle.

• Proceedings of the KSME Conference
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• 2000.04b
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• pp.119-124
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• 2000

The heat transfer characteristics of confined turbulent slot jet impingement on the flat plate with square rods(turbulence promoter) have been experimentally investigated. The effects of jet Reynolds number (Re=3900, 5800, 7800, 9700), dimensionless slot-to-plate distance(H/B=4, 6, 8) clearance(c) between square rods and the plate, and the length(d) of a side of the square rod were examined. Measurement or heat transfer rate were conducted using naphthalene sublimation technique. When square rods were inserted over the heat transfer surface, heat transfer rate was slightly increased in the wall jet region.

• Proceedings of the Korea Information Processing Society Conference
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• 2008.05a
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• pp.520-521
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• 2008

이 논문은 강원도의 U-Sports 시범 사업 일환으로 진행된 강원도 용평 스키장의 사각지역 관리를 위해 적용된 USN기술을 소개한다. 스키장의 사각지역은 사람의 왕래가 뜸한 외각이나 관제의 시각 영역에서 벗어난 급경사 아래 지역 등을 말하는데, 이런 지역에서 사고가 발생하여 거동이 어려워지면 관제 센터에서 이에 대한 신속한 대응을 하기 힘들다. 이 논문의 사각지역 관리 시스템은 다섯 개의 이미지 센서 및 노드가 설치된 사각지역의 이미지를 USN을 통하여 중앙 관제 센터에서 주기적으로 관찰할 수 있을 뿐만 아니라, 사고 당사자가 주변에 설치된 긴급 버튼을 누를 경우에는 긴급 이미지가 관제 센터로 즉시 전송되어 신속한 구조를 가능하게 한다.

• Proceedings of the Korean Nuclear Society Conference
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• 2002.10a
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• pp.161-161
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• 2002

• 보건세계
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• v.62 no.5
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• pp.9-9
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• 2013

정부와 사회단체는 소외된 계층을 보호하고 구제하기 위해 그간 많은 복지정책을 시행해왔다. 하지만 우리 주변에는 주민등록 말소자, 미등록 외국인 근로자, 노숙자 등 복지정책의 사각지대에 놓인 많은 이들이 여전히 제도권 내 의료 서비스조차 원활하게 받지 못한 채 어렵게 살아가고 있다.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2011.10a
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• pp.287-288
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• 2011

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2011.10a
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• pp.685-686
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• 2011

• The KIPS Transactions:PartD
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• v.16D no.2
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• pp.249-256
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• 2009

This paper introduces an efficient USN (ubiquitous sensor network) for monitoring blind areas in a skiing resort, developed as a part of u-Sport showcase project of Gangwon Province. Blind areas of a skiing resort are dangerous and/or steep areas located aroud ski slopes, which are rarely traveled and not easily seen by a ski patrol. If an accident occurs in such a blind area, the main control center of the sking resort can hardly recognize the accident and provide first aid and rescue services promptly. The blind area monitoring system proposed in this paper monitors a blind area of a skiing resort using five battery-powered sensor nodes each of which has an image sensor on it and wirelessly transmits images around the blind area to the main control center on a regular basis, therebly allowing real-time monitoring of the blind area and prompt rescue services in case of accidents. Additionally, the monitoring system provides an emergency button which skiers injured in the blind area can push. If the button is pushed, an image around the button and an alarm signal are transmitted to the main control center and therefore the main control center can take prompt actions for rescuing the injured skiers.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.6
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• pp.143-152
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• 2000

The comer filling in shaped drawing process is an important characteristic, unlike the round drawing. It has also influence on the dimensional accuracy of the product. In this study, therefore, the shaped drawing process has been simulated by the three dimensional rigid-plastic finite element method in order to investigate the effect of process variables such as reduction in area and semi-die angle to the corner filling. The artificial neural network has also been introduced to reduce the number of simulations. To verify the results of simulations, experiments have been performed on the real industrial products. According to the results, the main process variable on the corner filling is the combination of semi-die angle in the irregular shaped drawing processes, but in the case of regular shaped drawing processes, reduction in area has great influence on the corner filling.