An improved dynamic parameter model is presented based on cellular automata.The dynamic parameters,including direction parameter,empty parameter,and cognition parameter,are formulated to simplify tactically the proces...An improved dynamic parameter model is presented based on cellular automata.The dynamic parameters,including direction parameter,empty parameter,and cognition parameter,are formulated to simplify tactically the process of making decisions for pedestrians.The improved model reflects the judgement of pedestrians on surrounding conditions and the action of choosing or decision.According to the two-dimensional cellular automaton Moore neighborhood we establish the pedestrian moving rule,and carry out corresponding simulations of pedestrian evacuation.The improved model considers the impact of pedestrian density near exits on the evacuation process.Simulated and experimental results demonstrate that the improvement makes sense due to the fact that except for the spatial distance to exits,people also choose an exit according to the pedestrian density around exits.The impact factors 伪,尾,and 纬 are introduced to describe transition payoff,and their optimal values are determined through simulation.Moreover,the effects of pedestrian distribution,pedestrian density,and the width of exits on the evacuation time are discussed.The optimal exit layout,i.e.,the optimal position and width,is offered.The comparison between the simulated results obtained with the improved model and that from a previous model and experiments indicates that the improved model can reproduce experimental results well.Thus,it has great significance for further study,and important instructional meaning for pedestrian evacuation so as to reduce the number of casualties.展开更多
Pedestrian evacuation is actually a process of behavioral evolution. Interaction behaviors between pedestrians affect not only the evolution of their cooperation strategy, but also their evacuation paths-scheduling an...Pedestrian evacuation is actually a process of behavioral evolution. Interaction behaviors between pedestrians affect not only the evolution of their cooperation strategy, but also their evacuation paths-scheduling and dynamics features. The existence of interaction behaviors and cooperation evolution is therefore critical for pedestrian evacuation. To address this issue, an extended cellular automaton(CA) evacuation model considering the effects of interaction behaviors and cooperation evolution is proposed here. The influence mechanism of the environment factor and interaction behaviors between neighbors on the decision-making of one pedestrian to path scheduling is focused. Average payoffs interacting with neighbors are used to represent the competitive ability of one pedestrian, aiming to solve the conflicts when more than one pedestrian competes for the same position based on a new method. Influences of interaction behaviors, the panic degree and the conflict cost on the evacuation dynamics and cooperation evolution of pedestrians are discussed. Simulation results of the room evacuation show that the interaction behaviors between pedestrians to a certain extent are beneficial to the evacuation efficiency and the formation of cooperation behaviors as well. The increase of conflict cost prolongs the evacuation time. Panic emotions of pedestrians are bad for cooperation behaviors of the crowd and have complex effects on evacuation time. A new self-organization effect is also presented.展开更多
A simulation study on occupant evacuation in high-speed railway stations(HSRSs) was presented in China.Pathfinder was employed as the simulation platform and a typical HSRS in a medium-sized city in China was selected...A simulation study on occupant evacuation in high-speed railway stations(HSRSs) was presented in China.Pathfinder was employed as the simulation platform and a typical HSRS in a medium-sized city in China was selected for model development.The model was carefully calibrated and validated by comparing simulation results with field data.Evacuation efficiency could be improved with the increased door width while such effect decreased when the door width reached a marginal value.And the marginal value varied under different occupant densities.An exponential function between evacuation time and occupant density was fitted,indicating that occupant density significantly affected evacuation efficiency.A set of different evacuation strategies were compared,in terms of their evacuation performances.It was found that a balanced door usage would result in more efficient evacuations in HSRSs.Thus occupant flows were suggested to be managed considering door capacity.To avoid potential safety issues caused by such strategy(e.g.,more occupants could be evacuated from a smaller area designed with higher door capacity),occupants needed to enhance their awareness of following evacuation guidance instead of panic escape in emergencies.Moreover,such safety issues could also be avoided during the design phase that the evacuation capacity was designed to be proportional to the room capacity for each floor.The results of this study provide valuable information for HSRS design and flow management in China.展开更多
基金Project is supported by the National Natural Science Foundation of China (Grant Nos. 71071013,71001004,71071012,and71131001)the Fundamental Research Funds for the Central Universities,China (Grant No. 2011YJS241)
文摘An improved dynamic parameter model is presented based on cellular automata.The dynamic parameters,including direction parameter,empty parameter,and cognition parameter,are formulated to simplify tactically the process of making decisions for pedestrians.The improved model reflects the judgement of pedestrians on surrounding conditions and the action of choosing or decision.According to the two-dimensional cellular automaton Moore neighborhood we establish the pedestrian moving rule,and carry out corresponding simulations of pedestrian evacuation.The improved model considers the impact of pedestrian density near exits on the evacuation process.Simulated and experimental results demonstrate that the improvement makes sense due to the fact that except for the spatial distance to exits,people also choose an exit according to the pedestrian density around exits.The impact factors 伪,尾,and 纬 are introduced to describe transition payoff,and their optimal values are determined through simulation.Moreover,the effects of pedestrian distribution,pedestrian density,and the width of exits on the evacuation time are discussed.The optimal exit layout,i.e.,the optimal position and width,is offered.The comparison between the simulated results obtained with the improved model and that from a previous model and experiments indicates that the improved model can reproduce experimental results well.Thus,it has great significance for further study,and important instructional meaning for pedestrian evacuation so as to reduce the number of casualties.
基金Project supported by the National Key Technology Research and Development Program of the Ministry of Science and Technology of China(Grant No.2017YFC083300)the National Natural Science Foundation of China(Grant Nos.91646201,U1633203,and 51808422)the Independent Innovation Foundation of Wuhan University and Technology,China(Grant No.2019IVA011)。
文摘Pedestrian evacuation is actually a process of behavioral evolution. Interaction behaviors between pedestrians affect not only the evolution of their cooperation strategy, but also their evacuation paths-scheduling and dynamics features. The existence of interaction behaviors and cooperation evolution is therefore critical for pedestrian evacuation. To address this issue, an extended cellular automaton(CA) evacuation model considering the effects of interaction behaviors and cooperation evolution is proposed here. The influence mechanism of the environment factor and interaction behaviors between neighbors on the decision-making of one pedestrian to path scheduling is focused. Average payoffs interacting with neighbors are used to represent the competitive ability of one pedestrian, aiming to solve the conflicts when more than one pedestrian competes for the same position based on a new method. Influences of interaction behaviors, the panic degree and the conflict cost on the evacuation dynamics and cooperation evolution of pedestrians are discussed. Simulation results of the room evacuation show that the interaction behaviors between pedestrians to a certain extent are beneficial to the evacuation efficiency and the formation of cooperation behaviors as well. The increase of conflict cost prolongs the evacuation time. Panic emotions of pedestrians are bad for cooperation behaviors of the crowd and have complex effects on evacuation time. A new self-organization effect is also presented.
基金Study of Emergency Management Technology of Integrated Passenger Transportation Hub in Jiangsu Province,China(No.2012R06)National Natural Science Foundation of China(No.51608114)Shanghai Pujiang Program,China(No.15PJC093)
文摘A simulation study on occupant evacuation in high-speed railway stations(HSRSs) was presented in China.Pathfinder was employed as the simulation platform and a typical HSRS in a medium-sized city in China was selected for model development.The model was carefully calibrated and validated by comparing simulation results with field data.Evacuation efficiency could be improved with the increased door width while such effect decreased when the door width reached a marginal value.And the marginal value varied under different occupant densities.An exponential function between evacuation time and occupant density was fitted,indicating that occupant density significantly affected evacuation efficiency.A set of different evacuation strategies were compared,in terms of their evacuation performances.It was found that a balanced door usage would result in more efficient evacuations in HSRSs.Thus occupant flows were suggested to be managed considering door capacity.To avoid potential safety issues caused by such strategy(e.g.,more occupants could be evacuated from a smaller area designed with higher door capacity),occupants needed to enhance their awareness of following evacuation guidance instead of panic escape in emergencies.Moreover,such safety issues could also be avoided during the design phase that the evacuation capacity was designed to be proportional to the room capacity for each floor.The results of this study provide valuable information for HSRS design and flow management in China.
