• 대한기계학회논문집A
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• 제40권3호
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• pp.297-304
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• 2016

세라믹(AD-90 alumina, $B_4C$) 타일이 삽입된 금속 블록(4340-steel)에 텅스텐 합금(tungsten alloy)의 긴 운동에너지탄을 수직 고속 충돌시키는 수치해석을 수행하였다. 본 연구를 수행하기에 앞서 두 가지의 반무한판 충돌 모델의 침투 깊이에 대해서 검증을 하였다. 세라믹 재료는 JH-2 (Johnson-Holmquist) 모델을 적용하였고 계산된 침투 깊이를 실험값과 비교하여 만족할만한 결과를 얻었다. 앞서 언급한 판에 대해서 세라믹 타일의 세 가지 두께별로 금속판에 삽입된 위치를 다르게 하여 충돌 시뮬레이션을 수행하였다. 긴 관통자의 잔류속도, 잔류질량 그리고 잔류운동에너지를 얻어 세라믹 타일의 위치가 구조물의 방호 성능에 어떠한 영향을 미치는지 알아보았다. 그리고 단순 금속 블록 대비 세라믹 타일을 사용하는 경우의 질량 효율이 어떻게 되는지 확인해보았다. 마지막으로 이들을 토대로 질량효율 관점에서 최적 방호구조에 대한 평가를 수행하였다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2006년도 Grop Science and Biotechnology in the 21st Century
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• pp.29.2-29.2
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• 2006

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2005년도 춘계학술발표회
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• pp.733-734
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• 2005

• 한국항행학회논문지
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• 제15권6호
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• pp.962-969
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• 2011

본 논문에서는 GBAS 환경에서 전파위협원 위치 결정을 위한 TDOA/AOA 기반의 효과적인 DOA 추정 기법을 제안한다. TDOA 측정치만을 이용하여 추정한 1차 근사해와 DOP를 이용하여 DOA 추정 범위를 현저하게 감소시킴으로써 효과적으로 전파위협 신호의 DOA를 추정할 수 있다. 제안한 기법을 통하여 비슷한 연산량으로 더 높은 DOA 정밀도를 얻을 수 있으며, 동시에 전파위협원 위치 추정 정확도를 높일 수 있다. 또한 소프트웨어 기반의 시뮬레이션을 통하여 제안한 기법의 성능을 검증하였다.

• Journal of Radiation Protection and Research
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• 제3권1호
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• pp.23-28
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• 1978

유기석계(有機錫系) 안정제(安定劑)를 포함하고 있는 polyvinylchloride (PVC)의 내방사성(耐放射性)은 가소제(可塑劑)로서 첨가된 dioctylphthalate(DOP)의 양의 증가와 더부러 증가하며 이와 같은 내방사성(耐放射性)의 평가는 시료의 IR 특성 상에서 안정제의 해이(解離)에 기인(起因)하고 있는 $1,540{\sim}1,640cm^{-1}$에서의 흡수대가 선량과 더부러 변화하는 거동으로 살필 수 있다. 가소화된 PVC에서의 내방사성의 증가는 DOP 분자구조의 일부를 형성하는 benzen 환(環)에서 방사 에너지가 공명흡수 되기 때문이라 사료(思料)되며 이와 같은 견해(見解)는 방사선량에 대한 도전율변화특성(導電率變化特性)의 고찰 결과와도 잘 일치 한다. 실용적면(實用的面)에서 $0{\sim}100Mrad$ 사이의 선량에 대한 충분(充分)한 내방사성(耐放射性)을 얻기 위하여는 30phr 전후의 DOP 첨가량이 필요하다.

• 한국전기전자재료학회논문지
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• 제23권6호
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• pp.458-463
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• 2010

MLCC (multi-layer ceramic capacitor) is usually fabricated by lamination of predetermined number of single layers. Often, the state of MLCC before sintering is called the green state, whose strength comes from the adhesion between the dielectric material and the polymer binder. Therefore the lamination of a single layer before sintering can be easily deformed by environment due to the relatively lower strength. After the compression process, which helps single sheets cohereto with adjacent sheets, the MLCC green bar is preheated to resolve the probable internal stress. Unfortunately, unexpected deformation after preheating resulted in problems during cutting of the MLCC green bar. In this study, one of 2 primary hypotheses which were proposed to resolve the unexpected deformation after preheating was examined by quantitative experiment with GC/MS (gas chromatograpy/mass spectrometer). The proportion of deformation caused by DOP evaporation, which was primarily evaporated componet during preheating, to the total deformation of the MLCC green bar was found to be 53%.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.154-158
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• 2001

The heat treatment of PVC film containing PVC 65%, DOP(Dioctyl Phthalate) 32% as plasticizer, Ca-Zn stearates and surface agent was peformed under several conditions to study the degradation behavior of PVC sheet. In the case of H$_2$SO$_4$, the dehydrochlorination was ca.100% at 25$0^{\circ}C$ for 3h. The char involving the smaller pores was produced with hydrothermal treatment. The pore size became small with increasing the treatment time and temperature. In the case of treatment with Ca(OH)$_2$, the sizes of pores produced in char were about sever ~ 10${\mu}{\textrm}{m}$ at 2$25^{\circ}C$ for 12h. In the case of H$_2$SO$_4$, the size of pores were about 1${\mu}{\textrm}{m}$ in 5M H$_2$SO$_4$for 12h.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.746-750
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• 2001

The heat treatment of PVC film containing PVC 65%, DOP(Dioctyl Phthalate) 32% as plasticizer, Ca-Zn stearates and surface agent was peformed under several conditions to study the degradation behavior of PVC sheet. In the case of H$_2$SO$_4$, the dehydrochlorination was ca.100% at 25$0^{\circ}C$ for 3h. The char involving the smaller pores was produced with hydrothermal treatment. The pore size became small with increasing the treatment time and temperature. In the case of treatment with Ca(OH)$_2$, the sizes of pores produced in char were about sever ~ 10${\mu}{\textrm}{m}$ at 2$25^{\circ}C$ for 12h. In the case of H$_2$SO$_4$, the size of pores were about l${\mu}{\textrm}{m}$ in 5M H$_2$SO$_4$for 12h.

• 한국산업보건학회지
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• 제24권3호
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• pp.365-370
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• 2014

Objectives: The major objective is development of an eco-friendly non-phthalate plasticizer using crude glycol derived from the biodiesel process. Methods: Glycerol monolaurate(GML) was synthesized from glycol and triglyrcerides. Glycerol diacetomonolaurate(GDAL) was synthesized from GML and acetic acid. Results: The synthesis of the GDAL plasticizer was measured with nuclear magnetic resonance spectroscopy(NMR). Mechanical properties were measured by universal testing machine(UTM) and the experimental values were compared with phthalate plasticizers such as dioctyl phthalate(DOP). In particular, the values for tensile strength and elongations with GDAL were higher than with DOP. Conclusions: We confirmed the development of an eco-friendly non-phthalate plasticizer by NMR. Based on our results, applicability for food and drug packaging materials was found.

• Ocean Science Journal
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• 제40권4호
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• pp.183-190
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• 2005

We investigated the seasonal variability of tree alkaline phosphatase activity in seawater and alkaline phosphatase hydrolysable phosphorus (APHP) at 3 stations in Hiroshima Bay using alkaline phosphatase extracted from the dinoflagellates Alexandrium tamarense and Gymnodinium catenatum. The dissolved inorganic phosphorus (DIP) was lower than $1\;{\mu}M$ all samples; the lowest values were in May. The amount of APHP was high at the surface and bottom waters of all stations in May, showing DIP-depleted conditions. In August and November, the amount of APHP was much less than the amount of APHP in May, indicating that the availability of dissolved organic phosphorus (DOP) for these species was low and/or uptake during the dinoflagellate blooming might have occurred in the area. The results obtained from short-term variations of AP activity might suggest that the growth of dinoflagellates in this season may be partly supported by the AP produced by other diatoms.