{HEAD ~ The apparatus} 15 wherein {TAIL ~ said calculating means} comprises operational amplifiers configured in such a way as to calculate said first voltage and said corrected current 
wherein
{ HEAD ~ The apparatus } 15 wherein { TAIL ~ said calculating means } comprises operational amplifiers configured in such a way as to calculate said first voltage and said corrected current
HEAD HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH