Formalism Study for Agent-based Modeling in Nuclear Emergency Evacuation Simulation

Disaster prevention divided into structural and nonstructural measures. [1] Structural measures are made through visible structures. Examples include radiation monitoring facilities, radioactive protective equipment and so on. Non-structural measures are made through invisible structures, computer programming. Examples include emergency planning zone (EPZ), measurement of evacuation time etc. As a society becomes more complex, research into nonstructural measures is important. [2] In this study, we present a method for measuring evacuation time that is, one of the non-structural measures using agent-based model (ABM). In the ABM, an agent is an element that judges interactions in the program after setting attributes and behavioral rules in the evacuation model. In this study, ‘agent’ is defined as evacuees and infrastructure. In the authors’ previous study, evacuation model was developed. [3] In this model, the only interaction between evacuee ‘agent’ was described. However, the performance and behavior of evacuees are obviously affected by the interaction with infrastructure. The interface among various types of agents is not easily understood and implemented in an ABM because of their complexity. This study focused on how to clearly express interactions within ‘agents’ through the method, formalism. Furthermore, we developed a simple evacuation model using the results of formalism such that potential improvements for nuclear emergency evacuation can be investigated under dynamic simulation.