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The road network maintaining stability is critical for guaranteeing urban traffic function. Therefore, the vulnerable links need to be identified accurately. Previous vulnerability research under static condition compared the operating states of the old equilibrium before the event and the new equilibrium after the event to assess vulnerability ignoring the dynamic variation process. Does road network vulnerability change over time? This paper combines the vulnerability assessment with the traffic flow evolution process, exploring the road network vulnerability evaluation from the perspective of time dimension. More accurate identification and evaluation of vulnerable nodes and links can help to strengthen the ability of road network resisting disturbances. A modified dynamic traffic assignment (DTA) model is established for dynamic path selection (reselect the shortest path at the end of each link) based on the dynamic user optimal (DUO) principle. A modified cell transmission model is established to simulate the traffic flow evolution processes. The cumulative and time-varying index of vulnerability assessment is established from the viewpoint of traveler's time loss. Then the road network vulnerability assessment combined the traffic flow model with the vulnerability index. The road network vulnerability assessment of Bao'an Central District of Shenzhen, China, reveals that road network vulnerability does contain a dynamic process, and vulnerable links in each phase can be exactly identified by the model. Results showed that the road network would have a large vulnerability during the disordered phase when the main road fails. Therefore, prioritizing the smooth flow of main roads can weaken the impact of road network vulnerability exposure. [ABSTRACT FROM AUTHOR]

This study is devoted to handle disturbances occurring in a subway network during the off-peak period. By dissecting the relationship of transfer connections between connected lines, transfer passengers and non-transfer passengers as well as operating agencies are taken into consideration, respectively, and a trade-off method for timetable rescheduling is proposed to minimize the waiting time of all transfer passengers as well as the deviation from the planned timetable. We adopt the 𝜀 -constraint method to convert the bi-objective model to an integer linear programing model with single objective, which can be solved by CPLEX within seconds. The method is validated by some numerical experiments based on a real-world case derived from the Beijing Subway network. Results show that the proposed method is able to generate approximate Pareto optimal solutions and to provide decision support for dispatchers. [ABSTRACT FROM AUTHOR]