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

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發送短信 : Vertical Directivity Pattern of Train Noise