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

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Text this: Effects of downstream system on self-excited oscillations in collapsible tubes