• Proceedings of the SAREK Conference
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• 2008.11a
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• pp.113-118
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• 2008

For a R134a rotary vane compressor used for car air conditioners, characteristics of gas compression and oil supply have been studied. The compressor model under investigation has the low volume ratio of suction to discharge volumes so that there occur flow reversal from discharge port to compression chamber as the leading vane passes over the discharge port. As a result, the volumetric and adiabatic efficiencies turn out to be relatively low compared to other types of displacement compressors. Oil supply mechanism has been comprehended for mathematical modeling and oil flow rate has been calculated for the individual oil passages. This study on the gas compression and oil supply of a rotary vane compressor can be applied to a future design practice on a similar type of compressor.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2004.05a
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• pp.115-116
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• 2004

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.3
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• pp.1664-1670
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• 2015

As journal bearing has a sliding motion between the shaft and bearing with lubricating oil, it produces a hydrodynamic lubrication condition. Journal bearing can receive a large force because it takes a distributed load at the large friction face. As the oil groove or oil hole is made in the journal bearing surface for the journal bearing smoothly working under a hydrodynamic lubrication condition, sufficient lubricating oil is supplied through the clearance of journal bearing. The performance of the journal bearing is changed according to the shapes, sizes and positions of an oil groove. In this paper, the flow rate according to the oil groove shapes (triangle, semicircle and rectangle) among the various oil supply conditions was measured. The shape that discharges the highest flow rate was observed and the groove shape of optimal performance for the journal bearing was determined. The results showed that the flow rate increases with decreasing operating temperature, the influence of temperature on the flow rate decreased with increasing rotational speed, and flow rate in the triangular groove shape was greater than in other shapes.

• Aerospace Industry
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• v.60
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• pp.18-23
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• 1998

1998년 1월초 보잉사는 옛 맥도널더글라스사에서 개발해온 소형여객기 MD-95-30을 새로이 보잉 717-200으로 개칭하고 개발·생산을 계속한다고 발표했다. 동 717 모델의 명칭은 40여년전인 1956년 8월 31일에 처녀 비행한 미공군의 KC-135A Stratotanker 공중급유기에 주어진 이름으로 MD-95는 717의 기종명을 가진 두번째 항공기가 되었다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.06a
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• pp.581-582
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• 2007

• Proceedings of KOSOMES biannual meeting
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• 2017.04a
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• pp.14-15
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• 2017

• 해운
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• no.3 s.14
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• pp.12-15
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• 2005

해양오염방지협약(MARPOL) 부속서 I 13H 신설에 따라 단일선체 유조선에 의한 중급유 운송이 2005년 4월5일 이후에는 금지된다. 이에 따라 해양수산부는 3월10일 한국선주협회와 외항해운업계 관계자들이 참석한 가운데 대책회의를 열고 대응방안을 논의했다. 다음은 논의된 영향분석과 대처방안을 정리한 것이다(편집자 주)

• 전기의세계
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• v.43 no.9
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• pp.3-8
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• 1994

가변속 장치의 적용은 에너지 절감을 목적으로 한 것이기 때문에 대상기기의 선정에 있어 가장 중요한 점은 에너지 절감 효과의 예측이다. 따라서 본 연구에서는 그 대상을 정속 펌프인 급유 펌프에 두고 그에 적용되는 실제 운용방법 그리고 적용시 문제점을 분석하였으며, 이와 함께 VVVF(Variable Voltage Variable Frequency) 가변속 장치의 기능 및 에너지 절감에 대해 해석하였다.

• Digital Contents
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• no.11 s.150
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• pp.42-46
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• 2005

‘ www’는인터넷의상징과도같다. 지금처럼인터넷이폭넓게보급될수있었던이유중하나는어려운숫자도메인(IP Address)을간단한영문으로바꿔입력할수 있는시스템이등장했기때문이다. 이를기반으로몇몇얼리어댑터혹은전문가급유저만의전유물처럼여겨지던인터넷이대중화되기시작했다. 국내에서도이와 유사한움직임이나타나고있다. 영문에익숙하지않은어린이, 노인등의계층도쉽게인터넷을접하고이용할수있도록한글키워드서비스가시작된것. 한글키워 드서비스보급의선봉에우뚝선넷피아닷컴과디지털네임즈를분석했다.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.6 s.183
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• pp.37-43
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• 2006