Alternatively, if the area of {HEAD ~ the openings} 45 is small, the heat emission part 20 is disposed such that one heat emission part 20 corresponds to a plurality of {TAIL ~ openings} 45 
Alternatively , if the area of { HEAD ~ the openings } 45 is small , the heat emission part 20 is disposed such that one heat emission part 20 corresponds to a plurality of { TAIL ~ openings } 45
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH