A method, device, and {HEAD ~ system} for controlling a flow of {TAIL ~ a fluid} moving through a pipe are presented 
A method , device , and { HEAD ~ system } for controlling a flow of { TAIL ~ a fluid } moving through a pipe are presented
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH