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Traffic lights the earliest time only two colors red, green, later improved, increased a yellow ligh..

Nearly two years, the frequent occurrence of traffic accidents of Sydney region pedestrian casualtie..

Recently, the small make up to see, there are vehicles through the temporary traffic lights don'..

Traffic signal controller is the glue traffic light device, is used to control and adjust the traffi..

Traffic signal according to the key phase of intersection vehicle arrives situation, using the induc..

Branch when applying led traffic lights appear some questions, such as the led in the first use of t..

Traffic lights to edit our lives around, but for the specific meaning of traffic lights there are a ..