measuring air pressure in the air cup, the air pressure being directly related to {TAIL ~ the density} of {HEAD ~ the insulation} 
measuring air pressure in the air cup , the air pressure being directly related to { TAIL ~ the density } of { HEAD ~ the insulation }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD