改进的交通分配起点用户均衡算法

Improved Origin User Equilibrium Algorithm for Traffic Assignment

对起点用户均衡算法的流量转移、起点限制子网(Bush)的更新、成本更新策略及计算流程等关键问题进行了分析改进.探讨了Bush的最长和最短路径对查找方法,提出了流量转移的步长搜索方法及加速算法收敛的Bush更新方法.该方法优化了适合多线程开发的算法流程,并用不同规模的城市交通网络模型对算法进行效率测试和与其他算法进行对比.结果表明,该算法效率有较大的提高,可满足大规模城市交通网络模型计算速度和精度的要求.

Key tactics of an origin user equilibrium （OUE） algorithm such as flow shift from max- to minpaths, bush update and the algorithm＇s procedure were studied. The finding of max- and min-paths segmentation pair, the step size of bush flow shift and bush construction were studied to speed up the conver- gence. The algorithm＇s procedure was also optimized to take the advantage of multi-thread process. Convergence performances were compared with other algorithms by different size of urban transportation network. The improved OUE algorithm is more efficient and converges satisfactorily in a practical application.