动态交通路网中有效路径的确定方法

动态路径搜索是动态交通分配与动态车辆路径导行系统的关键技术，是建立智能交通系统的基础之一。本文给出了动态有效路径的明确定义，并将深度优先搜索的树搜索算法、寻路定向性、层次空间推理策略以及A^＋算法中的定向估价函数相结合，提出了动态有效路径的一种有效算法。在新算法中通过对交叉口延误的特殊处理，使得城市交通路网中的分向交叉口延误得以充分体现，并有利于将交通导行系统与交通控制系统相融合．文中同时对动态有效路径搜索在动态车辆路径导行和动态交通分配的应用作了初步分析。

Searching the Effective Paths in Dynamic Transportation Network

Searching paths in the dynamic transportation network, a key technology of dynamic traffic assignment (DTA) and dynamic vehicle route guidance system (DVGS), is the basis of building ITS. The conception of dynamic effective paths is given in this paper. Combining tree searching of depth-first, the orientation of searching the route, the strategy of spatial hierarchical reasoning and the node pricing function of A* algorithm, an algorithm of searching dynamic effective paths is proposed by simulating the tree's growing. The delay time at nodes in traffic direction is taken into consideration in the new algorithm. The analysis of the delay time at the nodes in traffic direction makes dynamic traffic control and DVGS combine easily. The application of the new algorithm in DTA and DVGS is mentioned in this paper.