Within the unified system, parallel processing computer systems, each having {HEAD ~ an input} controlling {TAIL ~ a plurality} of computers , generate and output user information at receiver stations 
controlling
Within the unified system , parallel processing computer systems , each having { HEAD ~ an input } controlling { TAIL ~ a plurality } of computers , generate and output user information at receiver stations
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH