{HEAD ~ The output} of {TAIL ~ the apparatus} is useful for controlling process parameters which affect image quality 
{ HEAD ~ The output } of { TAIL ~ the apparatus } is useful for controlling process parameters which affect image quality
HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH