• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1996년도 추계학술대회 논문집
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• pp.164-168
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• 1996

The relation between crystallinity and thermal history in low density polyethylene thin films and their effect on electric conduction phenomena and dielectric breakdown was studied. The low density polythylene thin films obtained by the solution growth method heat-treated at 140[$^{\circ}C$] for 2 h and subsequently cooling to various ways. The degree of crystallinity was estimated by the X-ray diffraction measurement for the specimen of slowly cooling, ICE quenching and liquid nitrogen quenching. The result shows that the crystallinity decreases become faster as the cooling speed increased, and that conduction phenomenon is governed by the space charge limited current in high field. It was found that the dielectric breakdown field increases with an increase in cooling speed and test number in self-healing breakdown method.

• 설비공학논문집
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• 제13권10호
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• pp.974-981
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• 2001

In this study, the minimum heat flux conditions are experimentally investigated for the spray cooling of hot plate. The hot plates are cooled down from the initial temperature of about$ 900^{\circ}C$, and the local heat flux and surface temperatures are calculated from the measured temperature-time history. The results show that the minimum heat flux point temperatures increase linearly resulting from the propagation of wetting front with the increase of the distance from the stagnation point of spray flow. However, in the wall region, the minimum heat flux point temperature becomes independent of the distance. Also, the velocity of wetting front increases with the increase of the droplet flow rate.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 추계학술대회 논문집
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• pp.65-68
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• 2000

Polyethylene, has long history and is widely used, was researched due to good electrical properties by many authors. But PE under stress has the critical defects of space charge accumulation and tree growth, so various methods such as catalyst, additives and blend to improve these problems have been execute, of which we selected blending method. As in our previous papers we investigated electrical conduction, dielectric and AC dielectric breakdown characteristics, we did DC dielectric breakdown characteristics in this paper. We selected pure LLDPE, pure EVA and LLDPE films mixed with EVA as specimens, which were mixed with the weight percentages of 50, 60, 70 and 80[wt%] to be thin film. DC applying voltage speed was 500[V/sec]. The relation between dielectric breakdown characteristics and the variations of super structure due to mixing was investigated, and especially trap level at amorphous region, threshold energy increment of conductive electron at free volume were considered.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1993년도 하계학술대회 논문집 B
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• pp.1174-1176
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• 1993

Morphology of low density polyethylene(LDPE) such as the degree of crystallinity changes with thermal history etc. In order to clarify the effects of morphological changes on electrical breakdown, we studied direct current and impulse breakdown phenomena of LDPE films heat-treated at 100[$^{\circ}C$] for 1[H] in silicone oil and subsequently cooling to various ways. The degree of crystallinity was estimated by the infra red absorption and X-ray diffraction measurements for the specimens of slowly cooled, cooled in water, original, and cooled in liquid nitrogen gas. As the result, we obtained that the first, second, third, and fourth was slowly cooled of 70.23[%], cooled in water of 61.6[%], original specimen of 56.75[%], and cooled in liquid nitrogen gas of 34.7[%] respectively. The crystalline size and distribution of specimens were researched by Differential scanning calolimeter measurements.

• 보존과학연구
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• 통권23호
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• pp.179-196
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• 2002

Sangyangmun is a written record which inform the date, time, history and reason of constructing a wooden building. We have conserved Sangyangmun which was discovered during the repairment and restoration of wooden building. From 1998 to 2002, We have completed the conservation of 27 pieces of 13 cases, for example Daeung-jeon, Bongjeonsa-Temple. First We investigated the material or damage condition of Sangyangmun, and carried out fumigation in order to prevent insects and fungi. Then Sangyangmun must be sealed hermetically using escal film in order to prevent the second damage.

• Preventive Nutrition and Food Science
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• 제6권4호
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• pp.247-252
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• 2001

The need to determine the permeability of organic vapors to polymeric films such as aromas, flavors, etc. has significantly increased in the food industry because of preservation and safety issues along with migration problems. However, due to the complex nature of the permeation process, there have been few investigations compared to nonorganic compounds. In this paper, we review the history of permeability studies and typical methods of permeability measurement such as the isostatic method and quasi-isostatic method for organic vapors. New instrumental developments and significant findings are also introduced and discussed.

• Bulletin of the Korean Chemical Society
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• 제18권9호
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• pp.958-961
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• 1997

The compatibility and the surface structure of blends of poly(styrene-co-acrylonitrile) (SAN) with either poly(methyl methacrylate) (PMMA) or hydrolyzed PMMA (H-PMMA) were studied in terms of film thickness, interaction, and surface free energy difference on the basis of X-ray photoelectron spectroscopy (XPS), attenuated total reflection Fourier transform IR spectroscopy and atomic force microscopy. The XPS measurement showed that the surface enrichment of (PMMA/SAN) blends with different AN contents of SAN and with different carboxyl acid contents of PMMA was dependent on the molecular interaction, the surface free energy difference between components and the sample preparation history. It was found that the compatibility of H-PMMA and SAN was reduced with increasing carboxyl acid content of PMMA.

• International journal of advanced smart convergence
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• 제8권2호
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• pp.140-146
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• 2019

Andrew Niccols's movie Gattaca (1997) inspired the formulation of the "Gattaca Argument" concerning the negative outcome of biotechnology, which has since been critiqued especially in the context of transhumanism and posthumanism. According this argument the development of genetic enhancement will produce a genetic discrimination and lead us to serious form of inequality. However, in particular transhumanists deny that here are reasons to worry and advocating instead the transformation of human condition in terms of genetic enhancement. Moreover, they question that genetic enhancement will necessarily lead to social inequality. In what follows, we will reexamine the Gattaca Argument and its critiques based on the movie in order to reassess the role the movie plays in the subsequent scholarly discussion. We will argue that existing critiques fall short of capturing the problem posed in the movie - the problem of the inhumane. Based on a hermeneutic approach to the movie we will both reconstruct the arguments and evaluate the transhuman counterarguments in terms of modern history of philosophical ideas.

• 한국기록관리학회지
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• 제5권2호
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• pp.153-165
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• 2005

중국은 역사가 길고 유구한 문화를 가진 국가이다. 수천 년의 역사는 방대한 수량의 당안문헌자료를 남겼다. 이러한 당안은 중국 민족의 "기억"을 구성하고 있다. 결승, 갑골, 청동, 비단에서 종이, 필름, CD까지 인류의 역사는 부단히 진화된 당안(기록(記錄)을 의미함)매체와 당안관리를 통하여 보존되고 연속될 수 있었다. 오늘날처럼 정보기술이 물밀 듯이 우리를 향하여 다가오는 시대에, 우리는 인류 기억의 "수호자"로서 옛 것과 새로운 것 그리고 변하는 것과 변하지 않는 것의 충격 속에서 가장 적당한 균형점을 찾을 수밖에 없다. 아키비스트는 한편으로는 최선을 다하여 전통 당안문헌의 생명을 유지시켜 장기적으로 충분히 이용될 수 있도록 하며, 다른 한편으로는 전자문서의 도전을 받아들여 새로운 관리방식으로 새로운 형태의 문서들을 보존시켜 인류의 역사를 연장하도록 시도하여야 한다. 정보시대는 인류 사회 발전의 새로운 단계로 문서당안의 디지털화(전자화) 역시 당안관리 역사의 긴 강에서 중요한 의의를 갖는 과정이다. 이 원고의 내용은 세 부분으로 이루어져 있다. 첫째 부분은 중국의 당안유산 보존 현황을 소개하였다. 특히 "중국당안유산사업"과 "특별서고(特藏室)"의 건설을 중점적으로 소개 하고, 둘째 부분은 중국의 당안디지털화 과정을 소개하였고, 셋째 부분은 전자문서관리의 표준화 건설을 소개하였다.

• 대한방사선치료학회지
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• 제25권1호
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• pp.57-67
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• 2013

목 적: 방사선 치료 중 정확한 환자의 셋업 확인과 선량 측정용으로 사용되었던 film을 대신 하여 현재는 전자포탈영상장치(EPID)가 장착된 장비가 증가하고 있다. 이에 본 논문은 전자포탈영상장치 사용 시 자세확인의 정확성과 선량측정의 유용성을 평가해 보고자 한다. 대상 및 방법: 대한방사선치료학회, 대한방사선종양학회, Pubmed에서 "EPID", "Portal dosimetry", "Portal image", "Dose verification", "Quality control", "Cine mode", "Quality - assurance", "In vivo dosimetry"와 같은 용어로 검색하여 획득한 50개의 자료(1997~2012)를 대상으로 EPID의 역사와 선량측정(dosimetry), 자세확인(set-up verification), EPID 특성으로 구분하여 EPID의 유용성을 분석 하였다. 결 과: EPID는 1세대 Liquid-filled ionization chamber, 2세대 Camera based fluroscopic, 3세대 Amorphous-silicon 순으로 발전하였으며, EPID 촬영 모드에는 크게 EPID mode, Cine mode, Integrated mode로 나뉜다. 필름과 EPID의 절대선량정확성 평가를 한 결과 EPID는 1%, EDR2 필름은 3% 이내로 나타나 오차 측정 정확도가 필름에 비해 EPID가 우수하다는 것을 알 수 있었고, 치료계획 시스템으로부터 계산된 기준 조사면과 EDR2 필름, EPID로 측정한 기준 조사면의 선량 분포를 중첩하여 감마 분석한 결과 필름과 EPID 모두 허용기준 3%/3 mm와 2%/2 mm에서 감마값이 1을 초과하는 화소(r%>1)가 전체 화소의 2% 이내였다. 또한 업무 부하 비교에 있어 세기조절방사선 치료에서 전 과정 QA를 수행하는데 소요되는 시간은 EDR2 필름이 약 110분, EPID가 약 55분으로 측정되었다. 결 론: 전자포탈영상장치의 이용은 선량측정과 자세확인에 있어 기존의 복잡하고 번거로웠던 film과 전리조(Ionization chamber)를 대체하기에 충분하였으며, 특히 세기조절방사선치료의 정도관리에 있어 매우 유용하고 효율적이며 정확한 선량 측정 장치임을 알 수 있었다. 또한, 전자포탈영상장치를 이용한 Cine mode 촬영은 횡격막의 움직임에 따라 유동성이 큰 폐와 간의 경우나 자세의 안정성이 불안한 직장암 환자의 경우 추가 선량 없이 실시간으로 종양의 위치를 확인 할 수 있다는 장점이 있어 최적의 방사선 치료 구현이 가능하리라 사료된다.