Collaborative Relationship Modeling and Analysis of Natech Emergency Response Organizations Based on Stochastic Petri Net

Natural hazard-triggered technological accidents (Natechs) are a type of multihazard coupled event with complex disaster evolution trends and serious consequences, resulting in high difficulty in collaborative responses. Currently, research on Natechs primarily revolves around evolutionary mechanisms and risk assessment. However, this complex form of disaster still requires relevant studies on response processes and organizational collaboration. The stochastic Petri net simulation method aligns well with this need, offering a suitable approach for addressing these gaps. Stochastic Petri nets (SPN) were introduced to clarify the Natech response process and analyze the synergistic relationship between organizations during the Natech response. First, the natech response process was framed by the logic of "scenario-task-organization"; the SPN's components were designed considering the characteristics of Natech events, and a proposal was made on how to construct the SPN model corresponding to a collaborative Natech response. Second, the performance of the analysis model was evaluated using the isomorphic Markov chain, and a method for examining organizational collaborative relationships was proposed. Finally, the model is validated by an example, and the characteristics of organizational task execution in Natech responses are summarized according to the busy probability of places and variation in the utilization of transitions. Analysis of task coordination relationships is proposed based on the SPN's structure, and the core and auxiliary workgroups are determined according to the actual task execution requirements to achieve better identification of responsible parties. Further, ways to improve Natech response collaboration are recommended: The role of the natural disaster response department is highlighted, for example, as it provides crucial information support during rescue operations. Relying solely on government departments may prove ineffective in responding to Natechs; thus, it may be necessary to involve social forces in the response effort. Flexible adjustments to deployment should be made to ensure the full utilization of limited disaster relief resources.