• Nuclear Engineering and Technology
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• v.45 no.1
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• pp.99-106
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• 2013

Thermal fatigue is a significant long-term degradation mechanism in nuclear power plants. In particular, as operating plants become older and life time extension activities are initiated, operators and regulators need screening criteria to exclude risks of thermal fatigue and methods to determine significant fatigue relevance. In general, the common thermal fatigue issues are well understood and controlled by plant instrumentation at fatigue susceptible locations. However, incidents indicate that certain piping system Tee connections are susceptible to turbulent temperature mixing effects that cannot be adequately monitored by common thermocouple instrumentations. Therefore, in this study thermal fatigue evaluation of piping system Tee-connections is performed using the fluid-structure interaction (FSI) analysis. From the thermal hydraulic analysis, the temperature distributions are determined and their results are applied to the structural model of the piping system to determine the thermal stress. Using the rain-flow method the fatigue analysis is performed to generate fatigue usage factors. The procedure for improved load thermal fatigue assessment using FSI analysis shown in this study will supply valuable information for establishing a methodology on thermal fatigue.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.241-242
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• 2003

울산지역은 1962년 공업 특구로 지정된 후 지난 30년 동안 우리나라의 기간 산업인 석유화학, 제련, 자동차, 조선공업 등 대단히 크고 많은 생산시설이 입주하여 운영 중에 있다. 특히 1974년부터 가동된 온산 국가공업단지에 많은 비철금속관련 업체들이 들어서면서 해양, 토양 뿐 아니라 대기중의 중금속 오염도를 가속 시켜 왔다. 최근 환경부 대기중의 중금속 측정망 분석 결과에 따르면 울산은 국내 여러 공단 도시에 비해 중금속의 오염정도가 매우 심각한 것으로 나타나고 있다. 특히, 온산공단의 대기나 토양의 카드뮴의 오염은 국내 최고치를 나타내고 있다. (중략)

• Proceedings of the KIEE Conference
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• 2007.11c
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• pp.134-137
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• 2007

한국수자원공사에서는 홍수예보용으로 위성통신망을 주망으로 사용하고, CDMA망이나 유선, 무선, VHF 망을 보조망으로 이용하고 있다. 현장에 설치되어 있는 우량관측국에 대하여 강우가 집중되는 기간동안 강우량에 따른 강우감쇠를 주망인 위성통신망과 보조망으로 이용하고 있는 CDMA망과 비교하여 각각의 감쇠 정도를 분석하고 이에 따른 대안을 제시하고자 한다.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2004.03a
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• pp.155-158
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• 2004

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1993.10a
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• pp.17-18
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• 1993

여름철 비가림 재배에서는 병발생이 노지재배보다 억제되고, 품질향상과 수량증가가 가능하지만, 기존의 간이시설은 작업성 및 고온장애 등의 많은 문제점을 내포하고 있다. 따라서 효율적인 형태의 비가림 시설을 보급하기 위하여 선정된 간이시설에 대하여 미기상해석에 의한 간이시설의 형태별 효율성을 검토하였다. (중략)

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• v.10 no.1
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• pp.333-336
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• 2005

• Journal of Korean Society for Atmospheric Environment
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• v.15 no.2
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• pp.101-111
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• 1999

In previous study, the local trends in dustfall chemistry and deposition were determined and the characteristics of chemical compositions among dustfall, TSP and rainwater were also compared. Based on the previous results, in this study, the effects of sea salts and soil and soil on the chemical composition of dustfall were studied and then the sources of dustfall in Cheju area were tentatively identified by principal component analysis(PCA)

• Proceedings of the SAREK Conference
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• 2005.06a
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• pp.149-149
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• 2005

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.719-722
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• 2008

Forest management is done to keep ecological health of forest and to enhancement of its function. Nowadays, the abnormal climate and heavy rain happen frequently. Therefore, there are opinions that the thinning slash allowed in the mountain is flowed in rivers, which can influence in flood damage. This study, we grasp moving characteristics of thinning slash through field survey and achieved basic study about the effect of thinning slash on the discharge capacity of rivers and stream structure.

• IEMEK Journal of Embedded Systems and Applications
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• v.16 no.5
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• pp.225-232
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• 2021

Deraining is one of the image restoration tasks and should consider a tradeoff between local details and broad contextual information while recovering images. Current studies adopt an attention mechanism which has been actively researched in natural language processing to deal with both global and local features. This paper classifies existing deraining methods and provides comparative analysis and performance comparison by using several datasets in terms of generalization.