Most of the signals in qatar has sensors to detect the traffic que in each lane, and signal changes from green to red if the lane is empty. This system helps to reduce the waiting time and improves traffic if u have noticed the new roundabout with signals.. putting timers beats the very purpose of this system as each signal will be of constant time if there is a timer.
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"Yesterday is the past,Tomorrow is a mystery,& Today is a gift that's why its called the PRESENT"
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