In this paper, we investigate pedestrian flows by using a newly-proposed cellular automaton （CA） model, which is based on the floor-field model. The interaction of pedestrians includes completion and cooperation, re...In this paper, we investigate pedestrian flows by using a newly-proposed cellular automaton （CA） model, which is based on the floor-field model. The interaction of pedestrians includes completion and cooperation, respectively reflected by a modified dynamic field and a position-changing behavior. Then we utilize this model to research lane formation phase in counter flow problem, involving the probability of lane formation phase, the average number of lanes and the microscopic behavior of pedestrians. It is found that the interaction between pedestrians and the different significant influences of average density of pedestrian flow on the features of lane formation phase.展开更多
This paper deals with the effects of traffic bottlenecks using an extended Lighthill-Whitham-Richards （LWR） model. The solution structure is analytically indicated by the study of the Riemann problem characterized b...This paper deals with the effects of traffic bottlenecks using an extended Lighthill-Whitham-Richards （LWR） model. The solution structure is analytically indicated by the study of the Riemann problem characterized by a discontinuous flux. This leads to a typical solution describing a queue upstream of the bottleneck and its width and height, and informs the design of a δ-mapping algorithm. More significantly, it is found that the kinetic model is able to reproduce stop-and-go waves for a triangular fun-damental diagram. Some simulation examples, which are in agreement with the analytical solutions, are given to support these conclusions.展开更多
We propose an extended cellular automaton model based on the floor field. The floor field can be changed accordingly in the presence of pedestrians. Furthermore, the effects of pedestrians with different speeds are di...We propose an extended cellular automaton model based on the floor field. The floor field can be changed accordingly in the presence of pedestrians. Furthermore, the effects of pedestrians with different speeds are distinguished, i.e., still pedestrians result in more increment of the floor field than moving ones. The improved floor field reflects impact of pedestrians as movable obstacles on evacuation process. The presented model was calibrated by comparing with previous studies. It is shown that this model provides a better description of crowd evacuation both qualitatively and quantitatively.Then we investigated crowd evacuation from a middle-size theater. Four possible designs of aisles in the theater are studied and one of them is the actual design in reality. Numerical simulation shows that the actual design of the theater is reasonable.Then we optimize the position of the side exit in order to reduce the evacuation time. It is shown that the utilization of the two exits at bottom is less than that of the side exits. When the position of the side exit is shifted upwards by about 1.6 m,it is found that the evacuation time reaches its minimum.展开更多
基金Project supported by the National Natural Science Foun-dation of China(Grant No.11172164)the National Basic Re-search Development Program of China(973 Program,Grant No.2012CB725404)
文摘In this paper, we investigate pedestrian flows by using a newly-proposed cellular automaton （CA） model, which is based on the floor-field model. The interaction of pedestrians includes completion and cooperation, respectively reflected by a modified dynamic field and a position-changing behavior. Then we utilize this model to research lane formation phase in counter flow problem, involving the probability of lane formation phase, the average number of lanes and the microscopic behavior of pedestrians. It is found that the interaction between pedestrians and the different significant influences of average density of pedestrian flow on the features of lane formation phase.
基金supported by the National Natural Science Foundation of China (Nos. 70629001 and10771134)the National Basic Research Program of China (973 Program) (No. 2006CB705500)+1 种基金the Research Grants Council of the Hong Kong Special Administrative Region of China(No. HKU7183/08E)the Research Committee of The University of Hong Kong (No. 10207394)
文摘This paper deals with the effects of traffic bottlenecks using an extended Lighthill-Whitham-Richards （LWR） model. The solution structure is analytically indicated by the study of the Riemann problem characterized by a discontinuous flux. This leads to a typical solution describing a queue upstream of the bottleneck and its width and height, and informs the design of a δ-mapping algorithm. More significantly, it is found that the kinetic model is able to reproduce stop-and-go waves for a triangular fun-damental diagram. Some simulation examples, which are in agreement with the analytical solutions, are given to support these conclusions.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11572184 and 11562020)the National Basic Research Program of China(Grant No.2012CB725404)the Research Foundation of Shanghai Institute of Technology(Grant No.39120K196008-A06)。
文摘We propose an extended cellular automaton model based on the floor field. The floor field can be changed accordingly in the presence of pedestrians. Furthermore, the effects of pedestrians with different speeds are distinguished, i.e., still pedestrians result in more increment of the floor field than moving ones. The improved floor field reflects impact of pedestrians as movable obstacles on evacuation process. The presented model was calibrated by comparing with previous studies. It is shown that this model provides a better description of crowd evacuation both qualitatively and quantitatively.Then we investigated crowd evacuation from a middle-size theater. Four possible designs of aisles in the theater are studied and one of them is the actual design in reality. Numerical simulation shows that the actual design of the theater is reasonable.Then we optimize the position of the side exit in order to reduce the evacuation time. It is shown that the utilization of the two exits at bottom is less than that of the side exits. When the position of the side exit is shifted upwards by about 1.6 m,it is found that the evacuation time reaches its minimum.
