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  _  __     ___     __   __    _____      _____  
 | |/ //   / _ \\   \ \\/ //  |  ___||   / ___// 
 | ' //   | / \ ||   \   //   | ||__     \___ \\ 
 | . \\   | \_/ ||   / . \\   | ||__     /    // 
 |_|\_\\   \___//   /_//\_\\  |_____||  /____//  
 `-` --`   `---`    `-`  --`  `-----`  `-----`

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Text this: wave scattering of interior vertical crack in plates and the detection of the crack