Papers by Author: Xing Li Li

Abstract: Asymmetric effect on the dynamical jamming transition in Biham-Middleton-Levine (BML) model with random sequential update rule is studied. The numerical simulations show that under periodic boundary condition, the system exhibits a sharp transition from freely moving phase to completely jamming phase, and the critical density is smaller than that of original BML model with synchronous update rule. For the asymmetry of system size, it can be found that the critical density is independent of the system size only when the width W and the length L are larger than some critical values respectively. Furthermore, the phase diagram shows that the asymmetric effect of the number of vehicles in two different directions plays a key role in reducing the occurrence of jam, and the underlying mechanism is analyzed.

Abstract: Based on the NS model, an extended cellular automaton model is proposed to simulate complex characteristics and energy consumption of traffic flow with some slowdown sections on a highway by considering the number, speed limit and distribution of slowdown sections. The simulation results show that the present model can exhibit a multi-phase coexistence phenomenon, i.e., the freely moving phase, the maximum flow phase and the jamming phase coexist in traffic system. The fundamental diagram shows that the number of slowdown section has no influence on the mean velocity and flow. However, energy consumption increases with increase of the number of slowdown section at low density. In addition, it can be found that the speed limit and distribution of different slowdown sections have an important effect on traffic flow and energy consumption, and the underlying mechanism is also analyzed.

Abstract: In this paper, a new viscous vehicular flow model proposed by Song et al is discussed from the perspective of the capability to reproduce nonlinear traffic behavors observed in real traffic. The linear stability condition for stationary and equilibrium flow is derived. Near the neutral stability curve, the Korteweg–de Vries (KdV) equation describing congested traffic pattern is derived with use of the reduction perturbation method. And the corresponding analytical soliton solution is obtained.

Abstract: As a kind of typical bottleneck influencing the transportation seriously, the lane reduction has seldomly been investigated with the optimal velocity model. In this paper, we study this issue using the optimal velocity model, in which two kinds of vehicles (fast and slow) are introduced. The asymmetric lane changing rules in the slowdown section and the lane squeezing behaviors at the bottleneck are taken into account. Under the periodic boundary condition, the numerical simulations are performed. The fundamental diagram is obtained. Then, the influences of speed limit and the length of the slowdown section on traffic are discussed in detail from the view of traffic control. The currents are dependent on the speed limit, but independent of the length.

Abstract: Based on the optimal velocity model, an extended optimal velocity model is proposed to simulate the movement characteristics of multi-types pedestrian queue by considering the differences among pedestrians (e.g., the differences in age and sex, etc.) and the asymmetric interaction. For the random distribution of pedestrian queue, the evolution rules of pedestrian movement and the formation mechanism of space-time pattern under two different boundary conditions are investigated. The numerical simulations show that the model can better describe the space-time distribution of pedestrian movement from microcosmic viewpoint and reproduce such important phenomena as the formation, dispersion of jams and multi-clusters movements.