Traffic flow investigation is an important step in the traffic planning.

交通规划中很重要的一环就是交通流调查。

youdao

The residents' trip survey and intersection traffic flow investigation in Shangyu city has been carried out, and reliable road network improvement programs been developed.

在上虞市开展居民出行调查和交叉口流量调查，制定路网改善的可靠方案。

youdao

An interim investigation has highlighted that improvements could be made to aid traffic flow by widening a section of the carriageway.

BBC: Traffic light in Shinfield Road