• 沒有找到結果。

1. 本研究利用 EDT 曲面定位法,透過格點搜尋方式,只需要簡單的四則運算 即可定位出震源位置,此外還結合了台灣地區三維速度構造模型及虛擬曲折 波線追跡法 (Pseudo-bending ray tracing method) ,能計算出接近真實環境的 地震波傳播路徑,進而提升走時精確度,讓定位結果更加精準。

2. 由於本研究將需要複雜計算過程的理論地震波走時資料預先計算並建立成 資料庫,因此當地震發生後,藉由 GPU 高速平型化計算的幫助下大幅減少 格點搜尋過程中需要花費的時間,提升地震定位速度。

3. 在本研究之定位程式所得出的結果中,對於震央誤差的改善程度還不錯,原 因可能在於利用了各個測站對 (station pair) 的關係,將測站的空間分布幾 何考慮進去,進而對於震央位置有較好的控制能力,但是對於深度部分則沒 有太明顯的改善情況。

4. 本研究之定位程式的定位精度受限於在建立理論地震波走時資料庫的過程 中所設置的格點大小,如果要劃分成更精細的格點會需要龐大的記憶體容量 來儲存資料庫中的理論地震波走時資料,進而增加讀取過程中的時間,較好 的解決方式為結合本研究之定位程式與 3DLOC 定位程式,先由本研究之定 位程式提供較為可靠的地震震源位置,再由 3DLOC 進行更精細的地震定 位。

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附錄 A 本研究所使用之 GPU 規格

產品名稱 GeForce GTX 1060 產品型號 06G-P4-6161-KR CUDA 核心數目 1280

預設 GPU 運作時脈 1506 MHz

記憶體規格 6144 MB GDDR5 記憶體時脈 8008 MHz

記憶體頻寬 192 GB/s

資料來源:

https://www.evga.com/Products/Specs/GPU.aspx?pn=f1aefe7f-3b97-444d-9859-ce b772861f3f

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