• 제목/요약/키워드: Environmental Comparison

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해양 수직 파일(Vertical Pile)에 작용하는 환경 하중하의 응력 해석 기법 비교 (Comparison of stress analysis tools for ocean vertical pile under environmental loads)

  • 조철희;김병환;김두홍
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2001년도 봄 학술발표회 논문집
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    • pp.121-127
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    • 2001
  • To investigate the stability and integrity of offshore structures, it is necessary to estimates the significant ocean environmental loadings. They include hydrostatic pressure, wind, wave, current, tide, ice, earthquake, temperature, marine growth and scouring. Waves are of major importance among them because of the large forces acting on submerged parts of the structure caused by accompanying water motions. For the comparison of stress and deflection analysis tools, a vertical pile is applied under environmental loads. The analysis is concerned with SACS(Structural Analysis Computer System), ANSYS and C program. SACS and C program have nearly the same results but not ANSYS. This study shows the comparison of results obtained from 3 different approaches.

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CMAQ 모델의 화학메커니즘(SAPRC99, CB05) 적용에 따른 수도권 오존농도 모의결과 비교 (Comparison of CMAQ Ozone Simulations with Two Chemical Mechanisms (SAPRC99 and CB05) in the Seoul Metropolitan Region)

  • 강윤희;오인보;정주희;방진희;김유근;김순태;김은혜;홍지형;이대균
    • 한국환경과학회지
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    • 제25권1호
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    • pp.85-97
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    • 2016
  • A comparison of ozone simulations in the seoul metropolitan region (SMR) using the community multiscale air quality (CMAQ) model with SAPRC99 and CB05 chemical mechanisms (i.e. EXP-SP99 and EXP-CB05) has been conducted during four seasons of 2012. The model results showed that the differences in average ozone concentrations between the EXP-SP99 and EXP-CB05 were found to be large in summer, but very small in the other seasons. This can be attributed that the SAPRC99 tends to produce more ozone than the CB05 in urban area like the SMR with low VOC/NOx ratio under high ozone conditions. Through quantitative comparison between two mechanisms for the summer, it was found that the average ozone concentrations from the EXP-SP99 were about 3 ppb higher than those from the EXP-CB05 and agreed well with the observations. Horizontal differences in ozone concentrations between SAPRC99 and CB05 showed that significant differences were found in southern part of the SMR and over the sea near the coast in summer.

비교 실험을 통한 PM-2.5 질량농도의 측정오차 분석 (Analysis of Measurement Error for PM-2.5 Mass Concentration by Inter-Comparison Study)

  • 정창훈;박진희;황승만
    • 환경영향평가
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    • 제19권4호
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    • pp.431-441
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    • 2010
  • In this study, inter-comparison for PM-2.5 was undertaken. The PM-2.5 mass concentrations using the gravimetric and beta-attenuation methods were compared during the winter in 2007. Two different types of conventional filter-based measurements (Cyclone type and Impactor type) were also collocated and the measurement data was compared with each other. As a result, continuous PM-2.5 data using beta attenuation method show a comparable mass concentration with gravimetric measurement when the inlet of beta-gauge sampler is heated. The results also showed that the cyclone type shows a little high PM-2.5 concentration than Impactor type. In all the sampling cases, the correlations between measurement methods are high. Subsequently, this study suggests that highly correlated relationship between PM-2.5 measurement instruments can be obtained through the inter-comparison results based on filterb-ased gravimetric method and more intensive measurement and theoretical studies are needed in order to clarify the measurement errors for different sampler types.