• Proceedings of the KSEE Conference
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• 2006.03a
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• pp.105-124
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• 2006

• 주택과사람들
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• s.199
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• pp.40-45
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• 2006

지난 10월 말 검단신도시 발표 이후 인천 부동산 시장이 스포트라이트를 받았다. 기존의 인천 경제자유구역과 택지지구 주변의 아파트, 토지 시장이 유망 투자처로 손꼽히면서 수요자들의 관심이 쏠리고 있다. 서울, 수도권 지역 집값 상승의 기폭제가 되었던 검단신도시를 다녀왔다.

• Proceedings of the Korean Nuclear Society Conference
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• 2004.05a
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• pp.171.2-171.2
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• 2004

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.9
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• pp.103-109
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• 2003

The development of a pulse gun used for the combustion stability rating test(SRT) has been domestically tried out since the SRT should be accompanied in the process of the development of LREs. At the beginning of the development, a rupture problem of the pulse gun body had been solved by changing its material and increasing its thickness. Also, the sealing test was undertaken for a pulse gun equipped with a membrane before conducting a explosion test and by using a specially designed jig after a explosion test. Since it is appropriate to reuse the holder of a pulse gun cavity for an actual SRT, a series of experiments for several variants has been taken to make it reusable. After all, the solution for a reusable holder of a pulse gun has been found and applied for complementing its specification.

• Journal of the Korean Society of Propulsion Engineers
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• v.18 no.2
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• pp.60-66
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• 2014

As a evaluation method of combustion stability in a liquid rocket engine thrust chamber, external disturbance devices are used. In the paper, the study on pulse-gun ignition tests for a combustion stability rating test of a thrust chamber was performed. Charging volume of pulse-guns was determined by confirming the intensities of the pressure waves from the ignition tests in the cold-flow conditions. While using same injector head, combustion instabilities were not encountered during 14 hot-firing tests without pulse-guns but combustion instabilities were triggered by pulse-gun ignition during 2 hot-firing tests. The results showed that the pulse-gun ignition test could be the evaluation method and could reduce the hot-firing test number for the stability rating of a thrust chamber.

• Journal of the Korean Society of Propulsion Engineers
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• v.21 no.5
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• pp.80-87
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• 2017

The performance of a pyrotechnic device that consists of donor/acceptor pair separated by a bulkhead relies on shock attenuation characteristics of the gap material and shock sensitivity of the donor and acceptor explosives. In this research, a micro Kapton flyer was accelerated by an exploding foil initiator (EFI) to figure out shock sensitivity of hexanitrostilbene (HNS) to impact. The averaged shock pressure and duration imparted to the explosive by flyer impact are measured by using a velocity interferometer for any reflector (VISAR) and impedance matching technique. Consequently, this research shows the possibility to determine the critical flyer velocity for initiating the miniaturized pyrotechnic unit by determining the relations between the impact velocity, the amplitude and width of impact loading.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.29 no.6
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• pp.270-275
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• 2019

Mica capacitor is being adopted for high voltage firing unit of guided weapon system because of its superior impact enduring property relative to ceramic capacitor. Reliability of localized mica high voltage capacitors was verified through environmental test like terminal strength test, humidity test, thermal shock test and accelerated life test for application to high voltage firing unit. Failure mode of mica capacitor is a decrease of insulation resistance and its final dielectric breakdown. Main constants of accelerated life model were derived experimentally and voltage constant and activation energy were 5.28 and 0.805 eV respectively. Lifetime of mica capacitor at normal use condition was calculated to be 38.5 years by acceleration factor, 496, and lifetime at accelerated condition and this long lifetime confirmed that mica high voltage capacitor could be applied for firing unit.

• The Korean Publising Journal, Monthly
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• s.135
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• pp.6-7
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• 1993

금융실명제는 출판계를 단기적인 자금압박에 시달리게 하고 있지만, 결국은 출판유통 광고 등에서 발견되는 구조적 모순을 제거하는 역할을 할 것으로 기대되고 있다. 더 나아가 도덕성 회복을 통한 올바른 출판문화를 가꿀 수 있는 기폭제로 삼아야 한다는 게 출판계의 공통적인 견해다.

• Proceedings of the Korean Society for Rock Mechanics Conference
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• 2007.10a
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• pp.470-485
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• 2007

• Journal of the Speleological Society of Korea
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• v.33 no.34
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• pp.30-40
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• 1993

온달굴은 천연기염물 제 261 호로 지정받은 문화재동굴로써 석회동굴이다. 원래 문화재에 해당하는 동굴들은 그 동굴이 지니고 있는 학술적, 문화재적인 가치를 분야별로 조사하여 이 동굴의 학술적 기폭을 삼어야 하며 그 가치기준에 의하여 천연기념물과 지방기념물 등등의 등급으로 구분하는 것이다. 물론 문화재에 해당하지 않는 그 밖의 동굴들은 자연동굴이라고 지칭하고 있음은 재언을 요하지 않는다.(중략)