为了便于信号控制策略的实施,针对路网中不同状态的交叉口,考虑子区内交叉口的同质性和关联性,提出了基于不同拥挤程度的路网动态分区方法.首先考虑相邻交叉口的交通关联度和相似度,建立了路网动态分区模型;然后结合谱图理论设计了动态分区算法,根据特征向量元素,对路段、交叉口的拥堵程度进行划分;最后提出了动态子区划分评价准则.算例结果表明,本文提出的方法既能有效地保证相关性较强的交叉口划入同一子区,又使得各子区内部路段的拥堵程度比较均衡,有利于各种不同拥挤程度的子区信号控制方案的选择和实施,对于交通信号控制方案的设计有实际的指导意义.
A dynamic network partitioning method based on different levels of congestion is proposed regarding the intersections of the road network in different states, considering both traffic homogeneity and degree of association. Firstly, a dynamic network partitioning model between adjacent intersections is established taking into account of traffic degree of similarity and association. Secondly, a dynamic network partitioning algorithm integrating the spectral clustering theory is designed and the elements of the feature vector about similarity matrix are used to divide the road network dynamically based on different levels of intersections and road sections. Then several dynamic sub-zone division evaluation criterions are put forward to evaluate the results of the division. Finally, a test example is designed and the study results show that, compared with other classification method, dynamic partitioning method proposed in this paper can effectively ensure intersections with strong correlations always assigned to the same sub-region on the one hand and interior sections of the sub-region a more balanced distribution about the degree of congestion on the other hand. It greatly facilitates the implementation of the sub-region signal control scheme about different levels of congestion separately, which is of great significance to design and implement traffic signal control program.