• 대한인간공학회지
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• 제18권2호
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• pp.121-132
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• 1999

This paper investigates the methodology to develop a layout of the simulator for measuring and evaluating human sensibility. Since the simulator layout is different from general building layouts in that it is organized in order to communicate systematically between facilities, laboratories to evaluate human sensibility and equipments to support experiments in simulator, two approaches based on eigenvector and cut tree are applied to develop a simulator layout. Qualitative input data (relationship chart. space requirements for each laboratory and equipment) are obtained and transformed into quantitative data. The information obtained by two approaches provides several meaningful clues to generate the simulator layout. The simulator layout is presented based on the obtained information by two approaches. Extracted quantitative data by using eigenvector and cut tree are meaningful of generating the simulator layout.

• Journal of the Korean Wood Science and Technology
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• 제10권3호
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• pp.196-196
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• 1982

There is a heavy stocked wood volume in the forest of Kang-Won Province compared with the other forests of Korean Provinces. It mainly, however, consists of non-productive and inferior hardwoods and shrubs which grows naturally. -This naturally grown hardwood forest should be cut and reforested with more economical confierous and diciduous tree species by artificial and natural regeneration under the positive government support. This study was carried out to survey the reasonable and economical utilization measures on harvesting wood products when existing hardwood forest should be cut primarily. This is the rust report on the resources and the classification of tree species by the uses of wood growing in the hardwood forest of Kang-Won Province. According to the investigation, 321 hardwood species are growing in this forest, and 141 species of them are extremely not suitable for wood production. The usable species as fuel wood was 180, and these are able to classify into the 22 groups by the uses of wood.

• 교육녹색환경연구
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• 제2권1호
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• pp.69-79
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• 2002

This paper investigates the methodology to develop a layout of the simulator for measuring and evaluating human sensibility. Since the simulator layout is different from general building layouts in that it is organized in order to communicate systematically between facilities, laboratories to evaluate human sensibility and equipments to support experiments in simulator, two approaches based on eigenvector and cut tree are support to develop a simulator layout. Qualitative input data (relationship chart, space requirements for each laboratory and equipment) are obtained and transformed into quantitative data. The information obtained by two approaches provides several meaningful clues to generate the simulator layout. The simulator layout is presented based on the obtained information by two approaches. Extracted quantitative data by using eigenvector and cut tree are meaningful of generating the simulator layout.

• Nuclear Engineering and Technology
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• 제44권4호
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• pp.405-414
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• 2012

In this paper, we propose a reliability estimation method for DI&C systems. At the system level, a fault tree model is suggested and Boolean algebra is used to obtain the minimal cut sets. At the component level, an exponential distribution is used to model hardware failures, and Bayesian estimation is suggested to estimate the failure rate. Additionally, a binomial distribution is used to model software failures, and a recently developed software reliability estimation method is suggested to estimate the software failure rate. The overall system reliability is then estimated based on minimal cut sets, hardware failure rates and software failure rates.

• 환경영향평가
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• 제18권6호
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• pp.359-366
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• 2009

CCS (Carbon Capture and Storage) is considered as the most promising interim solution to deal with the greenhouse gas such as $CO_2$ responsible for global warming. Even though carefully chosen geologic formations are known to contain stored gas for a long time period, there are potential risks of leakage. Up to now, applicable risk assessment procedures for the leakage of $CO_2$ are not available. This study presents a basis for risk analysis applicable to a complex geologic storage system. It starts with the classification of potential leakage pathways. Receptors and the leakage effect on them are identified and quantified. Then, a fault tree is constructed, which yields the minimum cut set (i.e., the most vulnerable leakage pathway) and quantifies the probability of the leakage risk through the cut set. The methodology will provide a tool for risk assessment in a CCS project. The outcomes of the assessment will not only ensure the safety of the CCS system but also offer a reliable and efficient monitoring plan.

• Applied Biological Chemistry
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• 제50권4호
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• pp.245-252
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• 2007

FTA(fault tree analysis)는 system 오류 관리를 위한 정성적/정량적 기법으로 적용되고 있다. FTA를 적용한 PCR의 오류 관리 system의 구축을 위한 시범적 단계로서 PCR 실행의 여러 단계 중 가장 간단한 단계인 '반응액의 제조 및 PCR 기기 사용 단계'를 모델로 하여 분석하였다. PCR 실행시 발생할 수 있는 오류를 연역적 논리 방식에 의해 fault tree의 형태로 규명하였다. Fault tree는 오류 관리의 최상위 요소인 top event를 중심으로 중간 계층을 이루는 intermediate events와 최하위의 요소인 basic events로 세분하여 구성하였다. Top event는 '반응액의 제조 및 PCR 기기 사용 단계에서의 오류'; 중간계층 events는 '기기 유래 오류', '실험행위 유래 오류'; basic events는 '정전상황', 'PCR 기기 선정', '기기 사용 관리', '기기 내구성', '조작의 오류', '시료 구분의 오류'로 분석되었다. 이로부터 top event의 원인 분석 및 중요 관리점을 도출하기 위하여 정성적/정량적 분석을 실시하였다. 정성적 기법으로 minimal cut sets, structural importance, common cause vulnerability를 분석하였고, 정량적 기법으로 simulation, cut set importance, item importance, sensitivity를 분석하였다. 정성적 분석과 정량적 분석의 결과에서 '시료 구분의 오류'와 '기기 조작의 오류'가 제 1중요관리점; '기기 관리의 오류'와 '내구성에 의한 오류'는 제 2중요관리점으로 일치되게 나타났다. 그러나 '정전상황'과 '기기 선정의 오류'는 정성적 분석에서만 중요관리점으로 분석되었다. 특히 sensitivity 분석에서 '기기 관리의 오류'는 사용 시간이 경과함에 따라 가장 중요한 관리점으로 부각되었다. 결론적으로 FTA는 PCR 모델 case에 대한 오류의 원인 분석 및 그 방지를 위한 중요관리점을 제시함에 따라, 궁극적으로 미래에 PCR의 오류 관리 system을 완성할 수 있는 효과적인 방법으로 사료된다.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2005년도 추계학술발표회
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• pp.544-545
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• 2005

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1997년도 추계학술대회 논문집
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• pp.409-412
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• 1997

The phenomenon of water tree degradation of underground distribution power cables is taking place in polymeric insulation materials under the existence of water and application of electric stress, but water tree is not easy to observe, o water tree features in power cables are shown after cutting and dying with methyleneblue. In previous method, it is impossible to acquire continuous treeing data, and when the insulation material has been cut, the micro crack(water tree) has been damaged. In this paper, to overcome these deflects, the etching method is made use of making needle electrode about 170[${\mu}{\textrm}{m}$] diameter, and AgNO$_3$(silver nitrate) solution is used as liquid electrode to accelerate the growth of water trees. As a result of this study, water tree is observed in real-time with microscope. Electrical tree owing to water treeing is initiated at low electric field and grown with discontinuous. Namely, water tree is shown up a different characteristics of tree growth.

• 한국자원식물학회지
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• 제14권3호
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• pp.241-246
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• 2001

옻나무 근삽에 의한 묘목의 생산성을 향상시키기 위하여 7종류의 삽상배지를 공시하여 신초발생율과 묘소질을 조사하였다 삽상배지는 PV(peatmoss vermiculite = 1 : 1)와 PVS(peat moss : vermiculite : sand = 1 : 1 : 2) 처리구에서 3주 후부터 신초가 발생되었고, 삽 식 10주 후의 신초발생율은 PVSC(peatmoss : vermiculite : sand : clay loam = 1 : 1 : 2 : 2)배지에서 80%로써 가장 높았다. 삽수당 신초형성수는 PH와 PVC 삽상배지가 2.2개로써 가장 많았고 HSC 삽상배지 는 1.3∼1.5개로써 가장 적었으나 통계적인 유의차는 인정되지 않았다. Peatmoss, vermiculite, sand 및 clay loam을 각각 1:1:2:2 (v/v/v/v)로 혼합한 PVSC 삽상배지가 옻나무 근삽의 삽상배지로 이용하기에 양호하였으며, 수장, 분지수, 엽수, 경직경 및 엽면적 등의 묘소질 역시 양호하여 본포에 이식하기에 적당하였다.

• 대한기계학회논문집
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• 제18권8호
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• pp.1974-1984
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• 1994

This paper presents a relative coordinate formulation for constrained mechanical systems. Relative coordinates are defined along degrees of freedom of a joint. Graph theoretic analyses are performed to identify topological paths in mechanical systems. Cut constraints are generated to handle closed loop systems. Equations of motion are derived in the Cartesian space and transformed to the joint space. Relative generalized coordinates are corrected to satisfy the cut constraints by a parametrizatiom method.