Early Bird Scheme for Parking Management: How Does Parking Play a Role in the Morning Commute Problem

This paper extended the Vickrey’s point-queue model to study the early bird parking mechanism during morning commute peak hours. We not only investigated how commuters choose departure times in view of morning commute traffic congestion and the discounted early bird parking fee, but also analyzed the conditions which are determined for the existence of the user equilibrium in the analysis model provided in this paper. Moreover, the tendency of the total queuing time and the incremental parking pricing revenue was derived along with the different choice strategy between early bird parkers (ERPs) and regular parkers (RPs). The results showed that the number of commuters was jointly determined by the desired time and the bottleneck capacity for different schedules. Additionally, the method of fare incentive showed a better effect on reducing queue than the initial no-incentive method with the instantaneous travel demand. Most importantly, the incremental parking revenue can be increased by properly adjusting the parking pricing gap between ERPs and RPs. Our research not only provided several important propositions for the early bird parking mechanism but also included the optimal solutions for optimal parking pricing and schedule gap in two groups of parkers. This work is expected to promote the development of early bird parking to mitigate morning commute traffic congestion and motivate the related research of schedule coordination for regulating parking choice behavior in morning peak hours.

Traffic flow modeling in fog with cellular automata model

To explore the traffic flow characteristics in fog, a modified one-dimensional cellular automata model is developed considering the limited visual distance of drivers in low visibility. We suppose that drivers can be categorized into seven groups according to the radical degree, and the number of drivers follows the Gaussian distribution in general road system. Capacity shrinkage is confirmed, and there is a positive correlation between the speed limits and extent of capacity shrinkage. When on-ramp bottleneck is considered in open boundary condition, bottleneck capacity fluctuates greatly when enter probability of on-ramp is lower than the threshold, and the dependency between main lane capacity and distance away from on-ramp is weak in most cases. Besides, capacity phase diagrams of various test scenario show that the bottleneck capacity will not improve after the entry probability of the main lane reaches a certain value. This study can be an inspiration for traffic flow modeling in fog and other infrequent weather.