This section outlines the main stages of the evacuation modeling procedure. The details of each stage are described in the corresponding sections.
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Building Model Analysis
1.1. Identification of areas where human movement is possible.
1.2. Identification of adjacent areas and the boundaries connecting them.
1.3. Construction of navigation graphs for boundaries.
1.4. Construction of path graphs.
1.5. Path planning for each individual.
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Main Simulation Loop
2.1. Proceed to the next simulation step, initializing necessary variables.
2.2. Evacuation situation analysis for each individual.
2.2.1. Determination of the group of people in the vicinity of the individual.
2.2.2. Identification of obstacles in the individual’s vicinity.
2.2.3. Calculation of local flow density around the individual.
2.2.4. Determination of the individual’s movement speed.
2.2.5. Determination of movement direction probabilities and the next position of the individual.
2.3. Movement of each individual.
2.3.1. Selection of movement direction.
2.3.2. Collision check with other people and obstacles.
2.3.3. Check for the possibility of moving through a checkpoint.
2.3.4. Move the individual to a new position.
2.3.5. Check for the need to update the boundary toward which the individual is moving.
2.4. Save simulation step data to output files.
2.5. Check simulation stop criteria.
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Postprocessing and Saving of Overall Simulation Results
3.1. Data on people passing through loggers.
3.2. Summary information about the evacuation scenario.
Factors Affecting Execution Time of Stages
The building model analysis stage and the main simulation loop are the most time-consuming stages of the evacuation modeling process and depend primarily on the number of objects in the model. The physical size of the model plays a lesser role.
The duration of the building model analysis stage is largely determined by the number of floors, platforms, and slabs, as well as staircases and ramps, doors and openings, exits, and waypoints.
The duration of the main simulation loop stage is mainly determined by the number of people in the building.
Depending on the specific model, either the building analysis stage or the main simulation loop may account for the majority of the total simulation time.