但是不可调光、闪灯还有灯色少这些问题依旧存在。

But problems of dimming, flicker, and light color remained.

youdao

针对我国城市道路交通信号控制中的灯色规定和一些常用信号正反两方面的影响因素等进行分析。

Aiming at the practice of traffic signal control in China, this paper analyzes the positive and negative effect of the commonly used traffic signal control designs.

youdao

1920年，世界上第一个三色交通灯投入使用。

In 1920, the world's first three-color traffic light was put to use.

youdao