• 환경영향평가
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• 제12권4호
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• pp.245-257
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• 2003

$SO_2$ concentrations in the Seoul Metropolitan Area (SMA) were predicted by the regional segment ISCST3 modeling. The SMA was segmented by three modeling regions where the weather monitoring station exists since the area of the SMA, approximately $100km{\times}100km$, is too wide to be modeled by one modeling domain. The predicted concentrations by the model were compared with the measured concentrations at 39 air monitoring stations located in the SMA to validate the ISCST3 modeling coupled with the regional segment approach. The predicted concentrations by the regional segment method showed better performance in depicting the measurements than those by the non-segment ISCST3 modeling. The correction methods of the calculated concentrations reviewed were here the correlation method by the first order linear equation and the ratio method of observed to calculated concentrations. The corrected concentrations by two methods showed good agreement with the measured data. The ratio method was, however, easily applicable to the concentration correction in case of a wide modeling region considered in this study.

• Smart Structures and Systems
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• 제14권4호
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• pp.659-678
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• 2014

The study is aimed at investigating the feasibility of a high TRL solution for a wing flap segment characterized by morphable camber airfoil and properly tailored to be implemented on a real-scale regional transportation aircraft. On the base of specific aerodynamic requirements in terms of target airfoil shapes and related external loads, the structural layout of the device was preliminarily defined. Advanced FE analyses were then carried out in order to properly size the load-carrying structure and the embedded actuation system. A full scale limited span prototype was finally manufactured and tested to: ${\bullet}$ demonstrate the morphing capability of the conceived structural layout; ${\bullet}$ demonstrate the capability of the morphing structure to withstand static loads representative of the limit aerodynamic pressures expected in service; ${\bullet}$ characterize the dynamic behavior of the morphing structure through the identification of the most significant normal modes. Obtained results showed high correlation levels with respect to numerical expectations thus proving the compliance of the device with the design requirements as well as the goodness of modeling approaches implemented during the design phase.

• 한국물환경학회지
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• 제30권6호
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• pp.638-646
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• 2014

Soil erosion from agricultural fields leads to various environmental problems weakening the capabilities of flood control and ecosystem in water bodies. Regarding these problems, Ministry of Environment of South-Korea prepared various structural and non-structural best management practices (BMPs) to control soil erosion. However, a lot of efforts are required to monitor and develop BMPs. Thus, modeling techniques have been developed and utilized for these issues. This study estimated the effectiveness of BMPs which are a vegetation mat with infiltration roll and Roll type vegetation channel using Soil and Water Assessment Tool (SWAT) model through the adjustment of the conservation practice factors, P factors, for Universal Soil Loss Equation which were calculated by monitoring data collected at the segment plots. Each BMP was applied to the areas with slopes ranged from 7% to 13% in the Haeanmyeon watershed. As a result of simulation, the vegetation mat with infiltration roll and Roll type vegetation channel showed 55% and 59% efficiency of soil erosion reduction, respectively. Also, Vegetation mat with infiltration roll and Roll type vegetation channel showed each 11.2% and 11.8% efficiency in reduction of sediment discharge. These roll type vegetation channel showed greater efficiency of soil erosion reduction and sediment discharge. Based on these results, if roll type vegetation channel is widely used in agricultural fields, reduction of soil erosion and sediment discharge of greater efficiency would be expected.

• 한국ITS학회 논문지
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• 제20권5호
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• pp.35-44
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• 2021

최근 고속도로 본선구간에서 발생한 교통사고에 대한 연구가 다수 수행되고 있으나, 램프와 같이 본선 외 구간에 대한 교통안전을 다루는 연구는 미미한 실정이다. 최근 5년(2015년~2019년)동안 램프에서 발생한 사고는 총 6,717건으로 이는 전체 고속도로 사고의 약 15%를 차지한다. 본 연구에서는 고속도로 램프구간에 대해 보다 정확한 사고 예측 모형을 제공하기 위해 포아송 감마(PG)와 포아송 역가우스(PIG)와 같은 다양한 통계 분포를 비롯하여 랜덤효과와 같은 기법을 적용하여 Simple 및 Full SPF를 구축하고 비교하였다. 교통 및 도로 기하구조 데이터는 로드뷰와 같은 다양한 시스템에서 수집되었다. 분석 결과, PIG 모형은 일반적으로 더 정확한 사고 예측을 제시하며, Simpe SPF와 Full SPF 모두에서 임의효과 모형이 더욱 우수한 성능을 나타내었다. 본 연구결과는 교통실무자들에게 정확한 사고 예측 모형을 기반으로 램프구간 교통안전을 증대시키고 이해할 수 있는 참고자료로써 활용될 수 있다.