Data mining in a digital map database to identify intersections located at hill bottoms and enabling {HEAD ~ precautionary actions} in {TAIL ~ a vehicle} 
Data mining in a digital map database to identify intersections located at hill bottoms and enabling { HEAD ~ precautionary actions } in { TAIL ~ a vehicle }
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