Fuzzy C- Means(FCM)를 이용한 도시유역 침수위험도 산정

Generally, inundation risk should be estimated to establish the flood disaster prevention policy in urban areas. In this study, a new method was suggested to estimate urban inundation risk. To develop the suggested method, we selected the five factors such as surface elevation, surface slope, pipe density, population and sediment in pipe, which have influence on the urban flood risk. Although the contribution of each factor to increase the risk must be considered at the same time, it is difficult to combine those contributions because each factor has different units. For this reason, the new method adopts the Fuzzy C-Means (FCM) algorithm which is one of the fuzzy cluster algorithms and makes it possible to consider the contribution of those factors that increase urban inundation risk at the same time. To verify the applicability of the suggested method, we applied the suggested method to Gunja basin in Seoul, Korea. Firstly, we collected the five factors for each sub-basin and used them to perform the FCM to estimate the inundation risk of each sub-basin. Then, the results obtained from the analysis were compared with the inundation history of Gunja basin. Comparison results showed that the high-risk sub-basins were in good agreement with the sub-basins which have the inundation history. Thus, the inundation risk estimation using FCM can be applicable to establish the disaster prevention policy for urban flood.