發送短信

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

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發送短信 : A study on the sound field in a vault with two open ends