• Journal of Korea Water Resources Association
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• v.37 no.5
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• pp.437-448
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• 2004

The traditional fixed areal DAD(rainfall Depth-Area-Duration) method, generally quoted in most hydrology texts, is a simple and useful procedure when watersheds are small and storm movement is not an important factor of consideration. However, it is difficult to obtain satisfactory results for the more apparent forms of storm movement such as typhoons, or for large watershed. In the latter case, especially the margin of error for the areal average rainfall increases proportionally to the area of study, causing biased result. To overcome these limitations, this study focuses on the storm-centered DAD analysis(moving area DAD method) developed and programmed by the isohyetal concept to obtain accurate and objective results. By comparing and analyzing the observed rainfall rates through both method, it was proved that the currently Proposed method more accurately reflected the average rainfall rate. In short, through this new method, approximately 130 storm events nationwide from 1969 to 1999 was analyzed and compared with the fixed areal method results.

• Proceedings of the Korea Water Resources Association Conference
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• 2017.05a
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• pp.236-236
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• 2017

본 연구에서는 강우의 시공간성을 파악할 수 있는 격자기반의 Average-point Tracking 프로그램을 이용하여 호우의 DAD(Depth-Area-Duration)를 분석하였다. IPCC 5차보고서에 따르면 1950년 이래로 다수의 극한 기상 및 기후 변화가 관측되었다. 그 중 일부는 인간의 활동과 관련된 것으로 많은 지역에서의 극한 호우 현상의 증가가 손꼽힌다. 이러한 극한 호우 현상 증가와 일부 저수지의 유출 증가 경향은 지역적 규모에서 홍수의 위험이 더 커졌음을 의미한다(Kim et al., 2016). 최근 이상기후 현상의 증가에 따른 강우양상의 변화로 게릴라성 집중 호우와 태풍의 빈도가 증가하고 있지만, 우리나라의 호우의 특성은 방위 및 진행방향에 따른 해석이 매우 복잡하여 강우를 정형화하기에 어려운 특징을 보인다. 또한 지속시간이 긴 호우의 경우에는 호우의 범위가 한반도 전체가 되는 특성 때문에 강우의 시 공간성과 관련된 관측 자료는 부족하며, 이러한 특성을 고려한 연구 또한 미진한 실정이다. 만약, 태풍과 같이 호우이동이 뚜렷한 경우, 기존의 적용되고 있는 유역중심의 DAD 분석 방법으로는 DAD 관계를 명확히 표현하기 어려우며 유역면적이 증가할수록 유역의 면적평균강우량의 오차도 증가하기 때문에 DAD 분석의 정확도는 낮아지게 된다. 따라서 본 연구에서는 호우의 형태와 이동을 고려하기 위해 시간에 따른 호우를 격자로 나누어 격자를 증가시키면서 면적평균최대강우량을 산정할 수 있는 Average-point Tracking 방법을 이용하여 DAD 분석을 실시하였다.

• Journal of the Korean Association of Geographic Information Studies
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• v.17 no.3
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• pp.68-81
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• 2014

This study aims to apply and evaluate the automatic DAD analysis method, which is able to establish the depth-area relationship more efficiently and accurately for point-to-areal rainfall conversion. First, the proposed automatic DAD analysis method tracks the expansion route of area from the storm center, and it is divided into Box-tracking, Point-tracking, Advanced point-tracking according to tracking method. After applying the proposed methods to 10 events occurred in Yongdam-watershed area, we confirmed that the Advanced point-tracking method makes it possible to estimate the maximum average areal rainfal(MAAR) more accurately with consideration of the storm movement and the multi-centered storm. In addition, Advanced point-tracking could reduce the errors of the estimated MAAR induced by increasing the area because it can estimate MAAR for each storm center and compare them at the same time. Finally, the DAD curve for the study area could be derived based on the DAD analysis of the selected 10 events.

• Journal of Korea Water Resources Association
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• v.47 no.4
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• pp.357-370
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• 2014

This study aims to develop a rainfall field tracking method for depth-area-duration (DAD) analysis and assess whether the proposed tracking methods are able to properly estimate the maximum average areal rainfall (MAAR) within the study area during a rainfall period. We proposed three different rainfall field tracking algorithms (Box-tracking, Point-tracking, Advanced point-tracking) and then applied them to the virtual rainfall field with 1hr duration and also compared DAD curves of each method. In addition, we applied the three tracking methods and a traditional GIS-based tool to the typhoon 'Nari' rainfall event of the Yongdam-Dam watershed and then assess applicability of the proposed methods for DAD analysis. The results showed that Box-tracking was much faster than the other two tracking methods in terms of searching for the MAAR but it was impossible to describe rainfall spatial pattern during its tracking processes. On the other hand, both Point-tracking and Advanced point-tracking provided the MAAR by considering the spatial distribution of rainfall fields. In particular, Advanced point-tracking estimated the MAAR more accurately than Point-tracking in the virtual rainfall field, which has two rainfall centers with similar depths. The proposed automatic rainfall field tracking methods can be used as effective tools to analyze DAD relationship and also calculate areal reduction factor.