• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1998.04a
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• pp.81-88
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• 1998

During an earthquake, there are three main components of excitation : horizontal excitation of the ground, vertical excitation of the pile due to superstructure feedback produced by vertical excitation of the ground, and the seawater excitation induced by the vertical ground shaking, that is, "the seaquake." These excitations could have effects on the soil plugs in open-ended pipe piles installed at offshore sites. In this study, seaquake excitation induced by the vertical ground shaking was simulated by pulsing the water pressure at the seabed. During a seaquake, due to induced excess porewater pressure and pressure gradients in the soil, the capacity of open-ended pipe piles installed in a simulated sea depth of greater than 220 m was reduced serevely and the soil plugging resistance was degraded by more than 80%. The soil plug was failed because of the upward seepage forces that developed in the soil plug due to excess pore water pressure produced in the bottom of the soil plug during the seaquake. The compressive capacity of an open-ended pile in a simulated sea depth of less than 220m was reduced only by about 10%, and the soil plug resistance was degraded by less than 5%.s than 5%.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.14 no.4
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• pp.32-40
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• 2005

The purpose of this study is to investigate variation of spark plug protrusion and PDA valve on the exhaust emission in a gasoline engine. Swirl is one of the important parameters that affects the characteristics of combustion. PDA valve has been developed to satisfy requirements of sufficient swirl generation for improving the combustion and reducing of emission level. Also, especially, the variation of spark plug protrusion have an important effect to the early flame propagative process. This is largely due to the high flame speed by short of flame propagation distance. So, this is forced that injection timing, spark timing and intake air motion govern the stable combustion. As a result, using two combustion chamber, without charge of engine specification and the variable spark plug location and PDA valve could be reduced exhaust gas at a part load engine conditions(1500rpm imep 3.9bar, 2000rpm imep 3.2bar, 2400rpm imep 3.9bar).

• Journal of the korean Society of Automotive Engineers
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• v.13 no.3
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• pp.32-42
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• 1991

In SI engine research the pressure data in cylinder is the most important fundamental ones leading to engine efficiencies and performances. It is, therefore, necessary to obtain accurate pressure data and yet it is often impossible to install a reliable data producing, flush-mounted type pressure transducer in a cylinder of small and medium size multicylinder SI engines. When flush mounting the transducer is not possible, the spark-plug type pressure transducer is commonly used as an alternative. In this case, the transmission tube of spark-plug type pressure transducer introduces distortions in the pressure signal. Efforts were made to understand the dynamic characteristics of spark-plug pressure transducer by shock tube tests and real engine experiments. In engine experiment the cylinder pressure data were simultaneously obtained by both flush mounted and spark-plug type pressure transducers of certain transmission tube geometry. Those pressure data collected by spark-plug type pressure transducer were tested for correction to flush mounted ones by the application of transfer function. As a result of the calibration the IMEP difference between F/M data and improved S/P data was shown to be corrected about 75-98% from the original ones.

• Proceedings of KOSOMES biannual meeting
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• 2018.06a
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• pp.194-194
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• 2018

• Transactions of the Korean Society of Automotive Engineers
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• v.8 no.4
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• pp.18-25
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• 2000

Ion current in an S.I engine cylinder is measured with the spark plug as a probe. The peak values are confirmed to show a fair correlation with local air-fuel ration and engine speed which implies that the ion current measured at the spark plug may provide a signal for the local mixture strength which is the key parameter in precise fuel control for future engines especially of gasoline direct-injected lean burn engines.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1998.05a
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• pp.229-234
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• 1998

우리나라는 현재 고유의 액체금속로 모델인 KALIMER(Korea Advanced Liquid Metal Reactor)의 개발을 통해 에너지 자원의 이용 효율 증대와 사용후 핵연료 및 초 장수명핵종 소멸처리 문제 등과 같은 에너지 안보와 환경 문제를 동시에 해결하려 하고 있다. 한편 KALIMER의 개바이 그 의미를 갖기 위해서는 고려중인 개념들이 기술적인 측면에서 기능성, 제작성, 안전성, 운용성, 독창성 등이 우수해야 할 뿐만 아니라 경제성이 확보되어야 한다. (중략)

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2003.04a
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• pp.128-131
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• 2003

양파는 묘의 소질에 따라 품질 및 수량에 미치는 영향이 매우 큰 작물로서 정식시묘의 크기가 클수록 수량이 증가하나 지나치게 크면 추대나 분구의 발생이 많아지므로 상품수량이 오히려 적어진다(서와 이, 1987, 하 등, 1998). 그러나 plug tray에 육묘한 묘는 용적이 적은 cell에 장기간 육묘되기 때문에 근권의 제한을 받아 관행의 토양육묘에 비해 묘의 생육이 저조할 뿐 아니라 연약 도장하여 기계정식에 장애를 초래하고 있다(정목, 1993). (중략)

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1996.03b
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• pp.40-47
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• 1996

An upper bound solution of tube drawing process using a fixed tapered plug has been obtained , which reduces to an solution for tube sinking by setting friction factor between tube and plug at zero. Effects of various process paraments have been discussed based on the solution.

• Proceedings of the KWS Conference
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• 2003.05a
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• pp.228-230
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• 2003

Recently, lots of joining methods of thin metal sheets are being developed in order to improve joint quality and productivity in manufacturing area. Current existing welding methods are continuously challenged as new materials and smaller thickness of metal sheets are required. In this study, laser plug brazing process was investigated as a new joining method of thin metal sheets. A CO2 laser system with automatic feeding of filler metal wire and flux was developed, and laser plug brazing experiments were conducted. The brazed joints were analyzed using various methods.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2013.11a
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• pp.63-64
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• 2013

개발된 Plug-In MCCB를 저압용 부스바에 설치하여 온도 특성을 분석한 결과 모든 상(phase)에서 기준 범위보다 적은 값을 나타냈고, 가장 높게 측정된 곳의 온도 역시 $13.7^{\circ}C$ 이었다. 또한 단시간 전류 시험 및 기계적 동작 시험 후의 온도 상승 시험에서도 $18.5^{\circ}C$로 측정되어 모든 부분의 특성이 양호한 것을 알 수 있다.