Data processing 51 Traffic signs and signals 51 Electronic traffic controls 46 Programmable controllers 28 Electric controllers 8 Control systems 2 Design and construction 2 Electronic circuit design 2 Interchanges and intersections 2 Internet social networks 2 Internetworking (Telecommunication) 2 Mobile communication systems 2 Radio circuits 2 Radio frequency 2 Roads 2 System design 2 Traffic flow 2 Wireless communication systems 2 Borland C++ 1 Programming (Electronic computers) 1 Traffic engineering 1