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Advanced information is increasingly being used as an external intervention tool to positively influence system performance. In many traffic assignment problems, the proportion of travellers that reroute is assumed to be constant (static rerouting behavior), whereas the number of travellers that modify their routes will change dynamically with the cost difference (dynamic rerouting behavior). In this paper, dynamic rerouting behavior is considered in day-to-day traffic assignment models to capture travellers’ reactions to advanced information. The properties of a dynamic rerouting weight function are studied using survey data. Our goal is to better understand the dynamic evolution of network flow. In the model, the rerouting weight varies dynamically with the cost difference between travellers’ estimated and expected costs. The linear stability of the equilibrium is analyzed. Both theoretical analyses and numerical simulations indicated that dynamic rerouting behavior increases the stability domain and decreases the parameter sensitivity. Additionally, the dynamic evolution of the cost and flow near the stability boundary is studied. The results show that the dynamic rerouting behavior helps to improve the convergence speed and dampen the oscillations in the evolution process. This paper explains the influence of dynamic rerouting choice behavior on the evolution patterns of transportation networks and provides guidance for network design and management.

To better understand the mechanism of air traffic delay propagation at the system level, an efficient modeling approach based on the epidemic model for delay propagation in airport networks is developed. The normal release rate (NRR) and average flight delay (AFD) are considered to measure airport delay. Through fluctuation analysis of the average flight delay based on complex network theory, we find that the long-term dynamic of airport delay is dominated by the propagation factor (PF), which reveals that the long-term dynamic of airport delay should be studied from the perspective of propagation. An integrated airport-based Susceptible-Infected-Recovered-Susceptible (ASIRS) epidemic model for air traffic delay propagation is developed from the network-level perspective, to create a simulator for reproducing the delay propagation in airport networks. The evolution of airport delay propagation is obtained by analyzing the phase trajectory of the model. The simulator is run using the empirical data of China. The simulation results show that the model can reproduce the evolution of the delay propagation in the long term and its accuracy for predicting the number of delayed airports in the short term is much higher than the probabilistic prediction method. The model can thus help managers as a tool to effectively predict the temporal and spatial evolution of air traffic delay.

Bicycle movements are always associated with lateral drifts. However, the impacts of lateral drift behavior, as well as variable lateral clearance maintaining behavior due to the variation of drift intensity, on mixed bicycle flow are not clear. This paper establishes a new cellular automata model to study typical characteristics of mixed bicycle traffic induced by lateral drift and its accompanying behavior. Based on derived positive correlation between passing speed and drift speed through survey, the occurrence probability of lateral drift and the degree of maintained lateral clearance are both introduced in accordance with the variance of passing speed. Then, in whole density region, firm conformity between simulation results and actual survey data is reached, which has seldom been achieved in previous studies. It is further verified that speed distortions in intermediate and high density region induced by assumption of constant lateral clearance requirements can be revised by introducing its variability characteristics. In addition, two contrastive impacts of lateral drift behavior are observed. That is, it causes speed fluctuation in low density while alleviating the speed fluctuation in relatively high density. These results are expected to be helpful to improve the simulation performance of mixed bicycle flow as well as depict more realistic vehicle-bicycle conflicts and so on.

In this study, a region-based dynamic model is proposed to depict the traffic dynamics of an idealised grid-like unidirectional road network, and the impact of heterogeneity of the network on macroscopic traffic flow is investigated. The equilibrium solutions are obtained by solving the dynamic model, and the method of linear stability analysis is applied to test the stability of the solutions. Accordingly, the curves of macroscopic fundamental diagram (MFD) for various inhomogeneous networks are plotted and the effects of network heterogeneity on MFD are revealed. Two network heterogeneity parameters, road capacity and the attraction strength of a sub-region in the road network, are considered and the results show that both of them affect the shape of MFD significantly. Numerical simulations are performed and the result supports the theoretical analysis.

As a typical bottleneck connecting freeway and common road, a ramp is an important traffic congestion area. Various traffic phenomena near ramps can be described by the Cell Transmission Model (CTM). However, real traffic data shows that traffic flow characteristics are far different for the ramp system with different ramp distances. The authors analyze traffic characteristics of ramp system with both an on-ramp and an off-ramp in Beijing 3rd ring road firstly. Then, it is found that ramp distance between the on-ramp and the off-ramp has a great impact on the capacity, due to the conflict of traffic flow between on-ramp and off-ramp. Finally the traffic conflict is considered in the merge cell and Capacity Drop CTM (CD-CTM) is proposed to embody the conflict. The simulation results suggest that CD-CTM fits the empirical data from Beijing 3rd ring road.

Characteristics of mixed traffic on a road with a signalized crosswalk are investigated by cellular automaton modeling. The interaction mechanism between vehicles and pedestrians is taken into account. Also, the inordinate behavior of vehicles near the crosswalk, and various behaviors of three types of pedestrians (i.e., careful pedestrians, normal pedestrians, and riskers), are incorporated into the proposed model. By using numerical simulations, the case for pedestrian flow consisting of careful and normal pedestrians is investigated. Phase diagrams and spatiotemporal diagrams are presented to show different traffic states. The results show that there is a critical value that divides the vehicle flow into a free flow portion and a congested flow portion. Interestingly, there are two critical values for pedestrian flow for a large signal cycle value, whereas there is only one critical value when the signal cycle value is smaller than a critical value. Finally, the variation of violating frequency...

To depict the mixed traffic flow consisting of motorized (m-) and non-motorized (nm-) vehicles, a new cellular automaton model is proposed by combining the NaSch model and the BCA model, and some rules are also introduced to depict the interaction between m-vehicles and nm-vehicles. By numerical simulations, the flux-density relations are investigated in detail. It can be found that the flux-density curves of m-vehicle flow can be classified into two types, corresponding to small and large density regions of nm-vehicles, respectively. In small density region of nm-vehicles, the maximum flux as well as the critical density decreases with the increase of nm-vehicle density. Similar characteristics can also be found in large density region of nm-vehicles. However, compared with the former case, the maximum flux is much lower, the phase transition from free flow to congested flow becomes continuous and thus the corresponding critical points are non-existent. The flux-density curves of nm-vehicle flow can also be classified into two types. And interestingly, the maximum flux and the corresponding density decrease first and keep constant later as the density of m-vehicle increases. Finally, the total transport capacity of the system is investigated. The results show that the maximum capacity can be reached at appropriate proportions for m-vehicles and nm-vehicles, which induces a controlling method to promote the capacity of mixed traffic flow.

Crosswalk with push button is prevalent in lots of cities for the purpose of promoting the efficiency of the crosswalk, and thus the delays of both vehicles and pedestrians can be reduced. This strategy has been confirmed to be effective in several developed countries. However, it is a pity that application of push button is aborted in some cities in China. In this work, diverse behaviors of vehicles and pedestrians are analyzed and discussed. Then, a microscopic model is developed by incorporating the interaction between vehicles and pedestrians. Numerical simulations are performed to reveal the characteristics of traffic flow and the efficiency of the signal control strategy. Also, the impacts of risker proportion and button reaction time, as well as the impacts of various behaviors as mass behavior, the patience of pedestrian and push button habit are investigated. It is expected that the results will be helpful to the strategy design of a signalized crosswalk in such developing countries as China.

In this work, a cellular automaton model is presented to depict the traffic flow at such a crosswalk with push button. The characteristics of vehicle flow with various arriving rate of pedestrians are investigated. Flux curves and spatiotemporal diagrams are plotted to show different traffic states and the phase transition features. A parameter, named as button reaction time, is introduced to represent the green time for vehicle flow after the button is pushed by a pedestrian. The effect of button reaction time on saturated flux is investigated. The results show that there is a critical value of button reaction time. The saturated flux increases rapidly when button reaction time is smaller than the critical value, while it increases slowly otherwise. Furthermore, theoretical analysis is performed and the results coincide with the simulation ones.