In order to maintain alternating nonstop traffic flow on the nonstop lane, three moving zones are marked along the fastroads by {HEAD ~ signal emitting fixtures} operated according to {TAIL ~ signal progression principles} 
operated according to
In order to maintain alternating nonstop traffic flow on the nonstop lane , three moving zones are marked along the fastroads by { HEAD ~ signal emitting fixtures } operated according to { TAIL ~ signal progression principles }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL