There is always a shortage of policemen, especially on roads. As for wild drivers, they are in abundance, and the consequences of road accidents are too serious to be ignored.
There are different methods of fighting against speeding – bans, video cameras, and fines. A more refined method is to place a dummy policemen at a dangerous point and, to increase the efficiency of the method, the dummy policemen is replaced from time to time with a real one. A similar method is placing police car winkers at roadsides. One will willy-nilly ease down, even if for precaution.
But the radical remedy to tame a wild driver is “lying policemen” (transverse projections on the road surface marked with white and yellow stripes). They are installed near schools, parks and other places where there are many pedestrians. Drivers have to ease down because in case of speedy driving, a severe shock is inevitable.
However, a contradiction occurs in this case. It happens that some vehicles (for instance, an ambulance, fire-engine, patrol-car) have to pass a road section rapidly. This problem is especially important for districts with a heavy traffic of such special vehicles.
The contradiction is resolved by using “object's copies”. Lines that imitate a “lying policeman” are drawn on the road. This is an ideal solution: not only a real policeman is absent, but a “lying” one as well, whereas the policeman's function is performed.

About other, less ideal solutions to the problem of forced speed restriction:
1. A rubber beam is hidden in the roadbed. It “jumps out” only in front of breakers. The breaker is identified by the video camera placed 20 m away from the beam. It is not clear, whether the camera will identify a special vehicle and switch off the mechanism. (“Klakson”, No. 10/2001, student's development)
2. A more humane method is as follows: soft, water-filled pipes restrict a carriageway. This acts psychologically on a driver and makes him ease down. (“Klakson”, No. 102001)
3. An inflatable “lying policeman” made of the new material “transcalm” has time to blow off before a law-abiding driver. It shakes only a wild driver. It is not quite clear how it can aid ambulances and fire-engines. And how that device will restore its shape. (“Segodnia”, No. 35/2001, development of British scientists and Dunlop company).