多用户类型弹性需求随机期望-超额用户平衡模型

为准确描述随机路网环境下出行者规避行程时间不确定风险的择路行为,推导了通勤者需求量服从对数正态分布和路段通行能力服从贝塔分布条件下计算期望-超额行程时间的计算公式,并在考虑出行者对行程时间的估计误差和路网服务水平对交通需求影响的基础上,建立了用等价变分不等式表示的多用户弹性随机期望-超额用户平衡模型.算例结果表明:随着需求水平波动程度和路段通行能力退化程度的加剧,当需求方差-均值比从0.5增至2.0、贝塔分布参数(l和m)从90和10变为10和10时,通勤者和非通勤者期望最小理解期望-超额行程时间分别增加了48.5%和99.2%.

Stochastic Mean-Excess User Equilibrium Model with Multiple Classes and Elastic Demand

In order to accurately describe travelers’ route choice behaviors for avoiding risks caused by uncertainties about travel time in a stochastic road network,the calculation formula of mean-excess travel time was derived for conditions when the traffic demand of commuters follows a log-normal distribution and the link capacity follows a Beta distribution,and a stochastic mean-excess user equilibrium model with multiple classes and elastic demand was built and formulated as an equivalent variational inequality.In the model,travelers’ perception errors on travel time and the effects on traffic demand caused by the road network service level were taken into account.The results show that,as the demand variation level and degradation degree of link capacity increase,when the ratio of variance to mean increases from 0.5 to 2.0 and the parameters(l,m) of Beta distribution change from(90,10) to(10,10),the average minimum perceived mean-excess travel time increases 48.5% for commuters and 99.2% for non-commuters.