# Evaluation of Subway Emergency Evacuation Based on Combined Theoretical and Simulation Methods
## 3 Methodology
### Simulation Process  
Pathfinder evacuation simulation software is an agent-based simulation software developed by Thunderhead Engineering in the United States for personnel evacuation research. It provides users with a graphical user interface for simulation design and operation, as well as 2D and 3D visualization tools for analyzing results. The software has the following advantages: (1) real-time dynamic simulation capabilities; (2) diverse personnel behavior settings; (3) strong software compatibility and interaction capabilities; (4) a rich set of emergency evacuation modules; (5) diverse experimental results.  
The simulation software supports two types of motion simulation modes: SFPE mode and Steering mode. In SFPE mode, the choice of evacuation route is primarily based on the walking path length, meaning that passengers will choose the nearest exit. During the simulation process, this mode can automatically identify the density of the evacuation space and adjust the speed of passengers accordingly. Additionally, the flow of passengers in this mode is restricted by doors. In Steering mode, the evacuation strategy is more realistic, as it combines route planning and collision avoidance among passengers, determining paths based on evacuation distance and the distance between passengers. Unlike SFPE mode, the flow of passengers in Steering mode is not restricted by doors, allowing them to successfully achieve their current movement goals and adapt to changes in the environment. Therefore, Steering mode has been widely applied in the field of emergency evacuation of personnel. The software is based on agent-based modeling, primarily used for crowd emergency evacuation simulations of large public events. These agents can be influenced by various factors in their surrounding environment, such as different floors, walls, and obstacles. The agents act based on their observations and perceptions of the environment, taking appropriate actions to achieve a specific goal according to their understanding of  
Figure 7: Weekly total passenger flow data distribution.  
the external environment and the knowledge they possess. This article uses Steering mode for the simulation experiments to more accurately model actual evacuation situations.  
In the simulation process using Pathfinder, the following steps are primarily involved:  
Step 1: Establishing the Fundamental Architectural Framework: this phase involves the acquisition of the real-time structural dimensions of the building and the configuration of the simulation environment.  
Step 2: Configuration of Simulation Parameters: Within the Pathfinder emergency evacuation simulation framework, the specification of personnel parameters is critical to the simulation's efficacy. The derived personnel parameters are subsequently integrated into the model.  
Step 3: Selection of Path Planning: In scenarios characterized by high passenger flow, the judicious selection of evacuation routes is essential for the successful execution of emergency evacuations. To facilitate the complete evacuation of individuals in such high-density scenarios, it is imperative to devise well-considered routing strategies.  
Step 4: Analysis of Simulation Outcomes: Following the establishment of the simulation framework, this study conducts an analysis of the simulation process, focusing on several key aspects: passenger flow, the cumulative number of evacuated individuals, and the total evacuation duration. A comprehensive analysis is performed for each operational condition. Figure 8 illustrates the flowchart representing the Pathfinder evacuation simulation process.