东南大学学报(英文版)
東南大學學報(英文版)
동남대학학보(영문판)
JOURNAL OF SOUTHEAST UNIVERSITY
2013年
3期
322-327
,共6页
朱森来%程琳%褚昭明
硃森來%程琳%褚昭明
주삼래%정림%저소명
交通流估计%高斯贝叶斯网络%证据传递%组合方法
交通流估計%高斯貝葉斯網絡%證據傳遞%組閤方法
교통류고계%고사패협사망락%증거전체%조합방법
traffic flow estimation%Gaussian Bayesian network%evidence propagation%combined method
为了估计交通流量,提出了一个使用先验路段流的贝叶斯网络模型。该模型把路段流量设为OD流量的父节点。在正态分布假设下,模型考虑了总交通流水平、路段流可变性以及交通量守恒的随机扰动。根据先验路段流确定所有变量的先验分布。通过更新一些观测的路段流量,给出后验分布。后验分布的方差往往随着路段流量的逐步更新而不断减小。基于得到的后验分布,给出点预测和相应的概率区间。为消除OD矩阵估计和交通分配之间的不一致,组合了贝叶斯网络和随机用户均衡模型,通过迭代得到均衡解。算例结果验证了提出的贝叶斯网络模型和组合方法的效果。
為瞭估計交通流量,提齣瞭一箇使用先驗路段流的貝葉斯網絡模型。該模型把路段流量設為OD流量的父節點。在正態分佈假設下,模型攷慮瞭總交通流水平、路段流可變性以及交通量守恆的隨機擾動。根據先驗路段流確定所有變量的先驗分佈。通過更新一些觀測的路段流量,給齣後驗分佈。後驗分佈的方差往往隨著路段流量的逐步更新而不斷減小。基于得到的後驗分佈,給齣點預測和相應的概率區間。為消除OD矩陣估計和交通分配之間的不一緻,組閤瞭貝葉斯網絡和隨機用戶均衡模型,通過迭代得到均衡解。算例結果驗證瞭提齣的貝葉斯網絡模型和組閤方法的效果。
위료고계교통류량,제출료일개사용선험로단류적패협사망락모형。해모형파로단류량설위OD류량적부절점。재정태분포가설하,모형고필료총교통류수평、로단류가변성이급교통량수항적수궤우동。근거선험로단류학정소유변량적선험분포。통과경신일사관측적로단류량,급출후험분포。후험분포적방차왕왕수착로단류량적축보경신이불단감소。기우득도적후험분포,급출점예측화상응적개솔구간。위소제OD구진고계화교통분배지간적불일치,조합료패협사망락화수궤용호균형모형,통과질대득도균형해。산례결과험증료제출적패협사망락모형화조합방법적효과。
In order to estimate traffic flow a Bayesian network BN model using prior link flows is proposed.This model sets link flows as parents of the origin-destination OD flows. Under normal distribution assumptions the model considers the level of total traffic flow the variability of link flows and the violation of the conservation law.Using prior link flows the prior distribution of all the variables is determined. By updating some observed link flows the posterior distribution is given.The variances of the posterior distribution normally decrease with the progressive update of the link flows. Based on the posterior distribution point estimations and the corresponding probability intervals are provided. To remove inconsistencies in OD matrices estimation and traffic assignment a combined BN and stochastic user equilibrium model is proposed in which the equilibrium solution is obtained through iterations.Results of the numerical example demonstrate the efficiency of the proposed BN model and the combined method.