應用雙因子存活分析於建立土石流預警臨界曲線之研究－以台灣神木地區為例

Establishment of Critical Line for Early Warning of Debris Flow Based on Two-Factors of Survival Analysis - A Case Study in the Sheng-Mu Area, Taiwan

蔡明璋(Ming-Chang Tsai) ； 周天穎(Tien-Yin Chou) ； 李秉乾(Bing- Jean Lee)

《中華水土保持學報》 47卷4期 (2016/12) Pp. 200-208

https://doi.org/10.29417/JCSWC.201612_47(4).0004

摘要

早期預警系統被認為是減少災害風險永續發展和保護人民生計的重要工具。而目前台灣及日本之土石流預警機制各有其優點以及可改進之處。本研究以台灣最常發生土石流之神木地區為研究範圍，並以集水區為警戒單元，同時考量時雨量及有效累積雨量雙因子作為發佈警戒之依據。本研究導入存活分析之概念建立安全曲線，進一步以神木地區歷年之無事件雨場資料及土石流事件資料，進行警報命中率、誤報率及評價值等數據分析，從安全曲線中評估討論該地區之土石流預警臨界曲線。本研究成果顯示，以無事件雨場作為建立安全曲線之基礎，不論該地區是否有土石流事件紀錄，均可快速建立集水區土石流預警臨界曲線。

關鍵字

土石流 ； 存活分析 ； 安全函數

並列摘要

Early warning systems are important measures for sustainable development of risk reduction and livelihood protection. Advantages and improvement have emerged in debris flow warning systems developed in Taiwan and Japan. This study took the Sheng-Mu region, which has frequent debris flow events, as the research area and used the watershed as the warning unit. Both hourly rainfall data and effective accumulated rainfall data are used for issuing warnings. This study established several safety curves with survival analysis theory. The model derives the warning critical line by analyzing the warning hit rate, false alert rate and evaluation values based on none-event rainfall data and debris flow event data. The result of this study showed that the warning critical line can be established quickly on the basis of non-event rainfall data regardless of whether debris flow events exist in a specific area.

並列關鍵字

Debris Flow ； Survival Analysis ； Safety Function