{HEAD ~ The system} 1, wherein {TAIL ~ a ratio} of plugged area to the total cell area of the flow through honeycomb substrate is less than 45% 
wherein
{ HEAD ~ The system } 1 , wherein { TAIL ~ a ratio } of plugged area to the total cell area of the flow through honeycomb substrate is less than 45 %
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH