In the technical parameter group, the prime parameter is price and the parameter set is {HEAD ~ a set} of {TAIL ~ performance parameters}  
In the technical parameter group , the prime parameter is price and the parameter set is { HEAD ~ a set } of { TAIL ~ performance parameters }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH