Dynamic Hyperpath Search for Transit and Traffic Assignment

交通网络用户的路径选择部分取决于行程开始时针对可预见的情况所做的决定，部分取决于行程展开时所做的选择。在交通网络的情况下，行程选择可能取决于诸如哪条线路首先到达特定站点或站台的因素，而在交通网络的情况下，行程选择可能受到诸如遇到的队列、交通信号的状态或驾驶员接收的信息的因素的影响。在公交分配中，通过定义一组可能是最优的基本路径（称为超路径）和出行选择策略来适应出行决策的影响。在交通分配中，随机用户平衡原理已被用来捕捉的影响，在行程的选择和不同的用户偏好。然而，通常形式的随机分配（C-logit，路径大小logit，交叉嵌套logit或probit）通常对可行路径的集合设置很少或特别的约束，并假设所有可行路径具有非零的使用概率。路径的选择被认为是随机效用变化的结果，而不是在旅行发生时面对展开的情况下的选择策略的结果。在这种程度上，在交通运输中对路径选择行为的处理比在交通分配中更为复杂。当拥塞和服务中断是一个突出的特征时，有必要在定义超路径时考虑时间依赖性。该提案的目的是将超路径和基于战略的决策的概念扩展到动态交通网络、交通网络和多式联运网络，然后评估这样做的好处。

Path choices by transport network users depend in part on decisions made in response to foreseeable circumstances at the start of the trip and in part on choices made as the trip unfolds. In the case of transit networks, on-trip choices may depend on factors such as which line arrives first at a particular stop or platform, whereas in the case of traffic networks, on-trip choices may be influenced by factors such as an encountered queue, the state of traffic signals, or information received by the driver. In transit assignment, the effects of on-trip decisions are accommodated through the definition of a set of elemental paths that may be optimal (referred to as a hyperpath) and strategies for on-trip choices. In traffic assignment, the stochastic user equilibrium principle has been used to capture the effects of on-trip choices and different user preferences. However, the usual forms of stochastic assignment (C-logit, path size logit, cross-nested logit or probit) generally place few or ad hoc constraints on the set of feasible paths and assume that all feasible paths have a non-zero probability of use. Choice of path is assumed to be the result of random utility variation rather than the outcome of a choice strategy in the face of unfolding circumstances as the trip takes place. To this extent, the treatment of route choice behaviour is more sophisticated in transit than in traffic assignment. Where congestion and service disruptions are a prominent feature, it is necessary to take time-dependency into account in defining hyperpaths. The objective of this proposal is to extend the concepts of hyperpath and strategy-based decision-making to dynamic transit networks, traffic networks and multi-modal networks and then assess the benefits of so doing.