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  _____     ______   ______      ___     ______   
 / ____||  /_   _// |      \\   / _ \\  |      \\ 
/ //---`'   -| ||-  |  --  //  | / \ || |  --  // 
\ \\___     _| ||_  |  --  \\  | \_/ || |  --  \\ 
 \_____||  /_____// |______//   \___//  |______// 
  `----`   `-----`  `------`    `---`   `------`

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發送短信 : Vertical Directivity Pattern of Train Noise