{HEAD ~ Apparatus} and method for defining {TAIL ~ a safety zone} using a radiation source for a vehicle 
for defining
{ HEAD ~ Apparatus } and method for defining { TAIL ~ a safety zone } using a radiation source for a vehicle
HEAD HEAD HEAD HEAD HEAD OTH OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH