Pedestrian Flow Evacuation Based On "Leader-Follower" Model

In an emergency evacuation,a "leader-follower" model is formed in the group,and the leader,as the central role,will have a profound impact on the evacuation outcome.Existing research tends to default that the leader has complete evacuation information and excellent decision-making ability,but in fact,the emergent evacuation leader is relatively random,and the leader does not necessarily have evacuation information and decision-making experience,and may not be able to make correct decisions.If the leader makes a wrong decision,he or she will mislead the followers under the "leader-follower" mechanism,which will adversely affect the evacuation.Based on the existing research and actual cases,this thesis analyzes the"leader-follower" model in emergency evacuation and constructs a social force model based on the "leader-follower" model,and adopts the concept of "information intensity".The concept of "information intensity" was used to determine the quality of the leader’s decision making,and the phenomenological observation and data analysis were conducted when the leader had complete information intensity,zero information intensity and intermediate information intensity.1.When leaders have full information strength,the more the number of leaders,the higher the tendency of evacuation efficiency,and when the number of leaders reaches a certain value,the evacuation efficiency is asymptotically constant;when leaders have zero information strength,the opposite is true,the more the number of leaders,the lower the tendency of evacuation efficiency,and when the number of leaders reaches a certain value,the evacuation efficiency is also asymptotically constant.2.When the number of leaders is the same,the greater the information intensity,the higher the evacuation efficiency.If the information intensity of leaders is too low,the evacuation efficiency will be lower than when there is no leader in the crowd.3.The number of pedestrians will add up to the influence of the leader’s information strength.When the leader’s information strength is low,the more the number of pedestrians,the lower the evacuation efficiency,and when the leader’s information strength is high,the more the number of pedestrians,the higher the evacuation efficiency.When there is only one leader in the scene,the information intensity is the most important factor to determine whether the leader can play a good leading role,and when there is more than one leader in the scene,the information synergy between leaders also affects the overall evacuation efficiency of the crowd.Therefore,this thesis proposes the problem of multi-leader synergy in emergency evacuation,and explores the influence of the degree of synergy between multiple leaders on the evacuation by three factors:exit selection strategy,initial position distribution,and call capacity size.It is found that by assigning non-duplicate safe exits for leaders in advance,the initial positions of leaders are regularly distributed-It is found that by assigning leaders to non-duplicate safety exits,by making the initial positions of leaders regularly distributed-preferably along the corners-and by ensuring that the call capacity of leaders matches the size of their assigned safety exits,multiple leaders can achieve better synergy and thus improve evacuation efficiency.This thesis reveals the evacuation pattern of pedestrians in the "leader-follower" model,explores the influence of the leader’s information strength on evacuation,and proposes several ways to strengthen the coordination among leaders.This thesis fills the gap of pedestrian evacuation research at the theoretical level when considering the situation where leaders do not have complete information,and provides guidance for emergency management in public places at the practical level.