基于图论的路网交通检测器之布点

为获取各路段的交通流量,将路网检测器布点问题转变成寻求有向图的流控制子图的问题.首先将任意路网抽象为有向图,定义弧的度表征路段的重要性,证明完全有向回路图(CCG)的若干结论后给出CCG最小流控制子图的获取算法,同时给出有向图非回路部分的流控制子图获取方法,进而提出能在任意路网上进行检测器优化布点的完整算法.算例选取广州火车东站附近的路网,结果验证了所提出的方法的有效性.

Layout of traffic detectors in road network based on graph theory

To determine the traffic flow on every road-section, we convert the road network detector layout into the flow control sub-graph(FCSG) in a directed graph. Firstly, a road network is abstracted as a directed graph, and the edgedegree measure is defined as the importance of a road-section. After proving several statements about the completely cyclic graph(CCG), we develop an algorithm for determining the minimal FCSG from a CCG. Meanwhile, a method for determining the FCSG from an acyclic graph is also given. Finally, the integrated algorithm for determining the detector layout in the road network is put forward. A numerical example employing the road network around Guangzhou Eastern Railway Station is given to demonstrate the effectiveness of the proposed method.