李顯智老師由材料受力時會沿著材料中的弱點及缺陷處出現裂縫的應力集中現象聯想到地殼以及地震的相互關係，發想出代表地殼脆弱性指標的最強地震圓弧雙交叉理論。本研究利用程式選取從1973年至2017年的地震目錄進行分析，並將結果與30份保留總能量釋放及發生深度，打亂時間及空間分布的虛擬地震目錄分析結果進行對照驗證。發現當搜尋區間設定為四年、地震篩選條件為深度70公里內、地震圓弧徑向誤差0.015、度向誤差0.1時，隔天可確認的最強地震圓弧雙凸交叉在時間間隔70天以上的預測成功機率遠高於虛擬地震目錄之結果，間接說明了最強地震圓弧雙交叉理論有相當大的機率具有力學意義。另外，等機率線分析也顯示關鍵預測半徑約為90公里，關鍵時間間隔約為100天，此二特性可解釋為地震圓弧雙交叉點附近產生應力集中現象，並在空間及時間都有局部化的特性，強烈的暗示最強地震圓弧雙交叉理論具有應力集中的意義。期望後續研究可以取得更多有效樣本，並比較更多參數優化預測模型，將此理論轉變為地震災害預防的有效利器。

This research thinks that the interaction of crusts and earthquakes is similar to plates with defects which can highly affect the strength in particular arrangement. Professor Hin-Chi Lei proposed a concept named strongest double intersection of circular arcs of earthquakes (SDICAE) which might be used as an important index of fragility of crusts. In this paper, SDICAEs are constructed by a MATLAB program named ASICAE with earthquake event around Taiwan from 1973 to 2017. In the other hand, 30 virtual earthquake event lists which conserves the total energy but randomize the spatial coordinate and time data are analyzed by ASICAE. Found that in the condition of search interval is four years, search depth between 0 to 70 km, TOLRe = 0.015, TOLde = 0.01, the prediction efficiency of true earthquake list is much higher than virtual earthquake event lists in the condition of double convex arc in 70 days. Furthermore, the isoprobability contours shows that the key search radius is 90 km, key time interval is 100 days. These results mean there might be stress concentration around the intersection point of SDICAE and Strongly implies that SDICAE might contain mechanical meaning. Hope the result of this paper will be the foundation of more accurate and more precise model to reduce earthquake hazard.

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