在车辆密度较高的情况下，交叉口间距大于某一值后，交通流量保持恒定值。

For a high density, when the distance between the intersections is greater than a certain value, the traffic flow maintains constant.

youdao

本文提出了一种利用定点检测器数据（流量和时间平均速度）来获取交通流密度的方法。

This paper has proposed a method to estimate traffic density using the output(traffic flow and time mean speed) of fixed traffic detectors.

youdao

以前的研究主要集中于宏观模型，讨论交通流量及密度的变化。

In the past, the hot point is the macroscopic model, which discusses the relationships among the traffic stream variables-speed, flow and density.

youdao