The controller detects transitions between inspiration and expiration via a flow signal to discriminate between {HEAD ~ the respiratory phases} of {TAIL ~ the patient} 
of
The controller detects transitions between inspiration and expiration via a flow signal to discriminate between { HEAD ~ the respiratory phases } of { TAIL ~ the patient }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL