近年來，時間反轉法已應用於平板破損偵測之研究，時反法是利用聲波時反回傳訊號的不變性，進而檢驗結構有無破損之情況。本文是以鋁合金平板為被偵測之對象，利用時間反轉法之概念並結合小波訊號處理的方式來對無裂縫之平板進行五個不同的實驗。實驗上先以激震器來激震實驗平板，接著再以加速規量測無裂縫平板之振動訊號，然後利用時間反轉法的概念以及小波訊號處理之技術來導入實驗之中，最後再由上述步驟所得之時域訊號與各量測點在激震點處之訊號圖做交相關函數分析，可得各量測點之最大交相關函數值並比較其結果，可得知時間反轉法可以恢復原始位置之振動訊號，也透過小波轉換處理過程提供較佳訊號補償的方式等，藉此來達到本文非破壞檢測之成效。

Recently, time-reversal method has been used in damage detection in plate. This method uses the recovering feature of time reversal signal to examine whether the structure is damaged or not. In the present investigation, an aluminum alloy plate is used as the detected object. Five different experiments on a plate are conducted by using time reversal method and wavelet signal processing. At first the experiment begins with the shaker to shake the plate at a specified location. Secondly, vibration signal of the plate has been measured. Then, the signal was processed by using the time reversal method and the wavelet signal processing. Finally, cross-correlation functions is used to analyze similarity between the return signal and the original signal. It is concluded that time reversal method can be used to recover the vibration signal at original location. It also indicates that by adding wavelet transform processing provides better signal recovery for the process. The ultimate goal of this study is to achieve the effects of the non damage detection.

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