Optimal number and location planning of evacuation leader in subway stations

Abstract

Evacuation leaders are conducive to the improvement of crowd evacuation efficiency when the evacuees are not familiar with the evacuation routes. The assignment of the number and positions of leaders is particularly important for the efficiency of evacuation. This paper formulates the optimization of passenger evacuation with leaders in a subway station by taking the labor, time, and safety costs into account. A maximal covering model with modifications is proposed to optimize the number and initial locations of leaders. The modifications of social force model are used to represent the dynamics of the evacuees and the leaders in simulations. We use the microscopic simulations of the evacuation of a subway station in Beijing to evaluate the performance of the proposed optimal evacuation strategy. Compared to empirically placing the leaders in the subway station, the proposed strategy shows better performance in terms of labor cost, evacuation time and safety level.