應用禁忌演算法進行降雨－淹水警戒值之優化：以臺北市文山區及新北市新店區為例=Applying the Tabu Search to Optimize a Rainfall-Inundation Warning Threshold: Case Studies in Wenshan, Taipei City and Xindian, New Taipei City

Taiwan located in Southeast Asia faces strong monsoon and three to four typhoons annually which may cause floods and may result in great damage as well as loss of property. The Water Resource Agency (WRA) has established a warning system as a non-structural measure. The concept of the warning system is based on rainfall threshold. When the cumulative rainfall reaches or exceeds rainfall threshold, the warning system will alert emergency response personnel. According to flood records provided by WRA between 2013 and 2015, the records of flood alarm showed that the warning accuracy of warning system needs to be improved. This study provides a methodology to build effective rainfall thresholds through the tabu search which optimizes rainfall thresholds based on 1、3、6、12 and 24 hour duration at the same time. The cases of study are in the Wenshan and Xindian district. And the rainfall events are divided into four situations, including correct alert (A), missed alert (B), false alert (C) and correct rejection (D). The results show that the rainfall thresholds of study have more alerting ability than official rainfall thresholds. The increasing maximum of accuracy is 40%, the increasing maximum of hitting flood during flooding time is 33.3%, and the increasing maximum of hitting flood during warning time is 5.7%. ? 2018, Taiwan Agricultural Engineers Society. All rights reserved.