• Journal of the Korean Ceramic Society
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• v.36 no.9
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• pp.937-945
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• 1999

In an effort to protect a RBSC(reaction -bonded SiC) tube SiC films from methyltrichlorosilane(MTS) by low pressure chemical vapor deposition were deposited in hydrogen atmosphere on the RBSC(reaction-bonded SiC) substrates over a range of input gas ratio(${\alpha}=P_{H2}/P_{MTS}=Q_{H2}/Q_{MTS}$=1 to 10) and deposition temperatures(T=1050~1300$^{\circ}C$). At the temper-ature of 1250$^{\circ}C$ the growth rate of SiC films increased and then decreased with decreasing the input gas ratio. The microstructure of SiC films was changed from granular type structure exhibiting (111) preferred orientation in the high input gas ratios to faceted columnar grain structure showing (220) in the low input gas ratios. The similar microstructure change was obtained by increasing the deposition temperature. These results were closely related to a change of deposition mechanism. Double layer structure having granular type and faceted ciolumnar grain structure from the manipulation of mechanism. Double layer structure having granular type and faceted columnar grain structure from the manipulation of the input gas ratio without changing the deposition temperatue was successfully fabricated through in -site process.

• Korean Journal of Environment and Ecology
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• v.24 no.5
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• pp.547-555
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• 2010

To investigate the vegetation structure of mountain ridge from Bammeorijae to Woongseokbong, 25 plots($400m^2$) selected by random sampling method were surveyed. Three groups of Quercus mongolica - Pinus densiflora community, Q. dentata community and Q. mongolica - Q. dentata community were classified by cluster analysis. Q. dentata, Q. variabilis, Pinus densiflora, Acer pseudosieboldianum and Q. mongolica were found as mostly dominant woody plant species in the Woongseok-bong area. In the future, the importance percentage of Pinus densiflora might be eventually decreased, but those of Q. mongolica, Q. variabilis and Q. dendata might be gradually increased. There were strong positive correlations between Pinus densiflora, Zanthoxylum piperium and Lindera obtusiloba; Q. mongolica and Rhododendron mucronulatum; Styrax obassia and R. schlippenbachii; Fraxinus sieboldiana, Zanthoxylum piperium and Styrax obassia; Acer pseudosieboldianum and Fraxinus sieboldiana; Cornus controversa and Corylopsis coreana were relatively weak negative correlations between Q. dentata and Q. mongolica; Lindera erythrocarpa, Q. mongolica and Q. variabilis; Q. mongolica, Larix leptolepis and Q. variabilis; Symplocos chinensis for. pilosa and Rhododendron mucronulatum. Species diversity index(H') of investigated groups was ranged from 0.09832 to 1.1102.

• Review of KIISC
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• v.21 no.2
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• pp.53-60
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• 2011

국제표준화기구 ITU-T에서는 연구그룹(Study Group)17이 정보통신 응용보안에 관한 표준화를 리드하는 연구그룹으로, 산하 4개의 연구과제(Question)를 구성하여 정보보호 국제표준을 개발하고 있다. 이 연구과제들 중 Q.7(의장, 나재훈, ETRI)에서는 안전한 응용 서비스라는 범주로 안전한 응용 프로토콜, 웹서비스 보안, P2P(Peer-to-Peer) 보안 등 정보통신환경의 응용서비스 보호에 적용될 수 있는 국제표준들의 개발을 담당하고 있다. Q.8(의장, Liang Wei, CATR)에서는 서비스 지향 구조라는 범주로 SOA(Service Oriented Architecture) 기술 및 통신 보안에 관련된 국제표준들의 개발을 담당하고있다. 현재 Q.7에서는 총 7건의 국제표준을 제정하였으며, 총 6건의 표준초안들이 개발중에 있다. Q.8의 경우는 현재 총3건의 표준초안들이 개발중에 있다. 본 논문에서는 해당 연구과제들의 표준화 현황과 향후 추진 방향을 제시한다.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.284-284
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• 2013

중 에너지 이온 산란 분석법(Medium Energy Ion Scattering Spectrometer, MEIS)은 50~500 keV로 이온을 가속 후 시료에 입사시켜 시료의 원자와 핵간 충돌로 산란되는 일차이온의 에너지를 측정하여 시료를 분석하는 기법으로, 원자층의 깊이 분해능으로 초박막의 표면 계면의 조성과 구조를 분석 할수 있는 유용한 미세 분석기술이다. 본 실험에서 에너지 70~100 keV의 He+ 이온을 사용하여 Pulse Width 1 ns의 Pulsed ion beam을 만들어 Start 신호로 사용하고 Delay-line-detector에 검출된 신호를 End 신호를 이용한 TOF-MEIS System을 개발하였다. 활용 가능한 분석시편으로 Ultra thin film 시편으로 1, 1.5, 2, 2.5, 3, 4 nm의 HfO2, 1.8, 4nm의 SiO2 시편을 분석 하였으며 Ultra Shallow Junction 시편으로 As Doped Si, Cs Doped Si 시편 및 Composition, Core/shell 구조의 Q-dot 시편으로 CdSe, CdSe/ZnS등 다양한 분석 실험을 진행 하였다. Composition, Core/shell 구조의 Q-dot 시편은 Diamond Like Carbon(DLC)의 Substrate에 Mono-layer로 형성하여 분석하였다.

• Proceedings of the Optical Society of Korea Conference
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• 2008.02a
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• pp.421-422
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• 2008

• Journal of the Society of Disaster Information
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• v.12 no.4
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• pp.389-402
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• 2016

This research is about Department of Emergency medical services students' cognition type of female 119 paramedics. The purpose of this research is to understand department of emergency medical servises students' cognition of female 119 paramedics and identify characteristics classified by types. To this end, applying Q-method, this research objectively analyzes 72 department of emergency medical services students' reaction who complete the field training about ambulance about female 119 paramedics. The result of the department of emergency medical services students recognized type of female 119 paramedics could be typed into four types. The type I is recognized as "Stamina limit type", the type II as "expert type", the type III as "guardian angel type", and the type IV as "feminine experience type". The type I has 28.3%, the type II has 12.7%, the type III has 6%, and the type IV has 3.8% explanation power, and these explain 51% of total variable. Generally department of emergency medical services students' cognition of female 119 paramedic is that they are expert in first aid but students' cognition is negative because of female 119 paramedic's limit of stamina, exposure to danger, and giving birth and infant care thus we should arrange solution of these cognition.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.32 no.1
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• pp.45-54
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• 2019

The damage detection method using the extended Kalman filter(EKF) technique has been continuously used since EKF can estimation the responses of the damaged building structure and the stiffness of the structure. However, in the use of EKF, the requirement of setting the initial paramters P, Q, and R has caused the divergence and instability of the state vector, and various researches have been conducted to determine theses parameters. In this paper, adaptive extended Kalman filter(AEKF) method is proposed to solve the problem of setting the values of P, Q, and R, which are important parameters determining the convergence performance of the EKF state vector. By using the AEKF method proposed in this study, the P, Q, and R parameters are updated every k steps. The proposed algorithm is applied for the estimation of stiffness and the damage detection of 3-DOF problem. Based of the verification, it can be found that the selection process for the values of P, Q, and R can improve the convergence performance of EKF.

• Korean Journal of Environment and Ecology
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• v.20 no.2
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• pp.103-113
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• 2006

To investigate the forest structure and to suggest basic data for forest management in the Mookdong area of the Weolchulsan National Park, thirty plots, each size is $100m^2$, were set up and surveyed. According to analysis of classification by TWINSPAN, the community was divided by five groups of Quercus variabilis-Q. mogolica(I), Q. variabilis(II), Q. variabilis-Pinus densiflora(III), P. densiflora(IV), Q. acutissima(V). The structure of communities were investigated using importance value. From the above results, it was anticipated that Quercus spp. will be dominance species instead of Pinus densiflora.

• Korean Journal of Environment and Ecology
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• v.11 no.4
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• pp.450-461
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• 1998

To investigate the plant community structure of Paekdam-Valley in Soraksan National Park, fifty-two plots have been set up and surveyed. By DCA ordination technique, the plant communities were classified into fkve community types, which were Pinus densiflora community and Q. mongolica community. It was supposed that Q. serrata community change to C. laxiflora community. It seemed that P. densiflora community, deciduous broad-leaved mixed forest and Q. serrata community would not be replace by another woody species. And it seemed that C. laxiflora community succeeded to Q. serrata community, so it was similar to the typical ecological succession of natural forest in the middle temperate regions. The range of Shannon's diversity index was 0.9827~1.2946(Unit area : 400m$^2$) and that was over another Korean National Parks area relatively.

• KDI Journal of Economic Policy
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• v.11 no.2
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• pp.1-17
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• 1989

본고(本稿)에서는 최근 미국연방준비은행(美國聯邦準備銀行)의 Hallman Porter Small이 개발한 인플레추정방법, 즉 화폐수량식에 장기균형유통속도(長期均衡流通速度)($V^*$), 잠재생산력(潛在生産力)($Q^*$), 장기균형기준물가(長期均衡基準物價)(P*)등의 개념을 적용하여 인플레식(式)을 추정하는 방법을 우리나라에 적용하여 보았다. 이를 위해 $V^*$는 인플레의 변동에 의해 구조적(構造的)으로 변동(變動)될 수 있다는 점과 $Q^*$는 고용(雇傭)뿐 아니라 투자의 함수라고 가정하고 자본스톡 및 $Q^*$를 내생적으로 추정하는 등으로 $V^*$, $Q^*$의 개념을 재정립하였다. 추정결과(推定結果)에 의하면 87년초 이후부터 실질생산(實質生産) 잠재(潛在)GNP를 초과하게 되었으며 통화공급(通貨供給) 역시 확대되어 $P^*$가 P를 넘어서는 현상, 즉 물가상승압력(物價上昇壓力)이 누적되어 왔으며, 이에 따른 물가불안이 해소되기에는 정책대응여하에 따라 상당한 기간이 소요될 수도 있을 것으로 냐타났다. 즉, 시뮬레이션결과 종합해 보면 물가상승압력(物價上昇壓力)의 완화를 위해서는 투자진작을 통한 잠재생산력(潛在生産力)의 확충과 아울러 긴축기조(緊縮基調)의 유지라는 일견(一見) 상반(相反)되는 정책기조(政策基調)를 동시에 추진해 나가야 할 것으로 나타났다. 현재의 경기국면에 대한 대응책으로는 통화공급(通貨供給)을 확대시키는 단순한 총량적 정책보다는 긴축기조(緊縮基調)를 유지하면서도 통화(通貨)의 신축적(伸縮的)인 공급이 투자(投資) 고용(雇傭) 등의 생산부문(生産部門)으로 원활히 흐를 수 있도록 하는 동시에 금융구조(金融構造) 경제구조(經濟構造)를 개선해 나가는 미시적이고도 포괄적인 정책이 요구된다 하겠다.