公共交通系统最佳路径算法

在分析城市道路网络最短路径算法(SP算法)和公交网络的特点的基础上,提出公共交通系统最佳路径算法.首先引入直达矩阵(T矩阵)和最小换乘矩阵(Q矩阵),讨论公交网络节点间换乘问题,得出最少换乘算法.利用Q矩阵确定节点间最少换乘次数,评价公交网络方便可达性.其次结合最少换乘算法,对最短路径算法(Dijkstra算法)进行改进.在标号过程中,利用Q矩阵对待检验T标号点进行筛选,减少T标号计算量,得到一条综合考虑路径长度和换乘的最佳路径.最后用一个简单的算例进行验算,说明该算法适用于一般公交网络,特别是换乘代价较高的公交网络.

Best-routing algorithm for public transportation systems

This paper presents a best-routing algorithm for public transportation systems on the basis of analyzing the shortest path algorithm in urban traffic network and the character of transit network. T matrix and Q matrix are introduced to discuss the path-planning problem and the least transfer algorithm is obtained. By using Q matrix the least transfer between two nodes can be determined and the performance of the transit network is evaluated. By integrating the algorithm into shortest path algorithm, a best path in consideration of path length and transfer can be found. Finally,a simple numerical example is given which shows that this algorithm is applied to general transit network especially to a high transfer-cost network.