{HEAD ~ A number} of runs of completed insulating glass components in {TAIL ~ queue} to be assembled into insulating glass units at the assembly station is monitored to identify a low queue condition of a given type of insulating glass component 
in
{ HEAD ~ A number } of runs of completed insulating glass components in { TAIL ~ queue } to be assembled into insulating glass units at the assembly station is monitored to identify a low queue condition of a given type of insulating glass component
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH