交通网络设计的优化模型及算法

通过对交通网络设计的问题及其研究现状的分析．对离散型交通网络设计问题进行了深入的研究。采用双层规划模型描述问题．其中上层规划模型是从交通规划者的角度出发．在建设资金受到约束的前提下．设计合适的路网结构．使得公路网中的交通出行能达到系统最优；而下层优化模型则是从路网使用者的角度出发．使交通出行达到用户最优，针对该双层规划模型．本文对上层模型使用SA算法求解．而下层模型则采用了基于路径搜索的GP算法进行求解．以此为基础设计了SA—GP算法对其进行求解。算例计算的结果表明．模型和算法都是有效的，求取的结果能显著改善路网的交通情况．而且上下层算法的收敛速度快，从而能为路网规划决策提供支持。

An Optimal Model and Algorithm for the Transportation Network Design Problem

The discrete transportation network design problem was analyzed and discussed.The bi-level programming model was used to describe the problem,and the upper model considered the point of view of the transportation planner,in order to design the optimal network structure and achieve system optimal based on the restriction of budget, the lower model considered the user of the network and in order to attain the user optimal.And we used the simulated annealing algorithm(SA) to solve the upper model as well as used the gradient projection algorithm(GP) based on the path search to solve the lower model.Application denoted the optimization method was rational,the result can improve the transportation status evidently,and the convergence speed of the algorithm is extraordinary rapid,so it provided scientific guidance for the decision-making of the transportation network planning.