I am using Ubuntu 12.04 . I will explain my situation first .
I am using A USB modem which frequently disconnect for an hour or so. Then i will plug off it from ports and will insert again .Then it will search again and connect .
My idea is , is there anything i can do else without plugoff the modem from USB ports , i mean restarting powersupply to modem or USB port .
One more point: I can't restart total USB's power-supply because my speakers are USB and sometimes i used to work by attaching the USB devices .
Help me guys , if i got this then you are going to save me from an daily exercise .
Thank you .