基于有效路径集逐步生成的网络交通流分配方法  

Network Traffic Assignment Method Based on Gradually Extending the Set of Effective Paths

作　　者：何胜学[1] HE Shengxue(Business School, University of Shanghai for Science and Technology, Shanghai 200093, China)

机构地区：[1]上海理工大学管理学院,上海200093

出　　处：《武汉理工大学学报（交通科学与工程版）》2021年第5期817-821,共5页Journal of Wuhan University of Technology（Transportation Science & Engineering）

基　　金：国家自然科学基金(71801153,71871144)。

摘　　要：在实际网络交通流分配中,由于一般无法预知或明列所有有效路径,因此基于路径的交通流分配方法难以被有效实施.针对上述问题,文中提出了在投影梯度类算法执行过程中,通过不断搜索最短路径来逐步扩展有效路径集合的改进方法,并在理论上证明了新方法可以最终确定所有起讫点对间实际被采用的有效路径,且对应路径的流量符合Wardrop第一原则.为了提高投影算法中投影算子的执行效率,针对投影集合特征,文中给出了一种无需迭代求解精确投影的算法.通过问题形式的等价转化,投影子问题可被转化为一个简单路网的交通流分配问题.根据网络平衡路径流量的特征,设计了求解投影精确解的无迭代算法.在算例分析部分,通过与基于路段的Frank-Wolf算法比较,证实了新方法的有效性.In the actual network traffic flow allocation,because it is generally impossible to predict or list all the effective routes,the route-based traffic flow allocation method is difficult to be effectively implemented.In view of the above problems,this paper proposed an improved method to gradually expand the effective path set by constantly searching the shortest path during the execution of the projection gradient algorithm.In theory,it is proved that the new method can finally determine the actually adopted effective paths between all pairs of starting and ending points,and the traffic of the corresponding paths conforms to Wardrop’s first principle.In order to improve the execution efficiency of projection operator in projection algorithm,an algorithm for solving accurate projection without iteration is presented according to the feature of projection set.Through the equivalent transformation of the problem form,the projection subproblem can be transformed into a simple road network traffic flow assignment problem.According to the characteristics of network balanced path traffic,a non-iterative algorithm is designed to solve the projection exact solution.In the part of example analysis,the effectiveness of the new method is verified by comparing with Frank-Wolf algorithm based on road section.

关 键 词：交通流分配 有效路径 单纯形约束 投影梯度法 

分 类 号：U491[交通运输工程—交通运输规划与管理]