考虑路段流量不确定性的OD矩阵反推算法
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文章编号:1672-5328(2008)03-0079-03
成卫 陈月明 董玉佩
(昆明理工大学交通工程学院,昆明 650224)
摘要:现有OD矩阵反推技术大都将路段流量确定为稳定不变的,导致反推精度不高。为了解决这一问题,以交通网络平衡和双层规划模型为理论基础,选取路段流量与实测流量之间的偏差平方和最小作为目标函数,删除OD矩阵的判别误差函数,将双层规划模型简化为单层规划,从而减少了计算量。以云南省某城市中心城区路网作为实际算例,采取用户平衡分配模型进行验证。结果表明,分配得到的路段流量与实测流量的相对误差都在12%以内,证明该方法与已有研究中以网络行驶时间最小作为目标函数的反推模型相比,精度更高。
关键词:交通规划;交通模型;OD矩阵;反推模型;双层规划;用户平衡分配
中图分类号:U491.1+2
文献标识码:A
OD Matrix Estimation Algorithm with Consideration to Uncertainty of Link Flows
Cheng Wei, Chen Yueming and Dong Yupei
(Faculty of Traffic Engineering, Kunming University of Science and Technology, Kunming 650224, China)
Abstract: Link flows are usually hypothesized as constant variables in the existing OD matrix estimation technology, which yields a low accuracy. Coping with this problem, this paper develops a method for OD matrix estimation based on network equilibrium theory and the two-tier planning model by minimizing the square deviations of the estimated and the observed link flows. This method reduces the calculation load by tossing out the OD matrix error-checking function and by simplifying the two-tier planning model as a single-tier planning model. A numerical example utilizing user-equilibrium assignment model applied to an urban central area network in Yunnan Province, China, shows that the difference between the modeled and the observed link flows is less than 12%, a higher accuracy compared with other OD matrix estimation models using the minimum network travel time as their objective function.
Keywords: transportation planning; transportation model; OD matrix; estimation models; two-tier planning; user equilibrium