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

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發送短信 : Vertical directivity of train noise