Objectives   Traditional disaster models focus on single disaster, deployed in various types of isolated business systems. For lack of considering complex chain relationships between different disasters, it's difficult to meet the requirements of disaster assistance analysis with the disaster cluster in multi-disaster coupling scenarios. Given the above problems, we propose a disaster model service chain orchestration method using disaster chain rules. In order to elaborate the proposed method, we take the earthquake as a primary disaster to compose a composite disaster scenario as an example, and prove the proposed method from three aspects: The construction of the logical disaster model service chain, the optimization and dynamic adjustment of the physical model service chain, and the web publishing of the disaster model service chain.

  Methods   The disaster chain theory is adopted to orchestrate the disaster model service chain. Firstly, the logic disaster model service chain is constructed based on the analysis requirements of disaster scenario and disaster chain rules. Secondly, the optimized quality of service(QoS) index evaluation system is adopted to select the optimal combined service link from the disaster model cluster to realize the simulation analysis function for complex disaster scenarios. In order to ensure the stability of the chain, a dynamic adjustment mechanism is proposed to solve the failure of model node in the chain. Finally, to support the interoperable processing of distributed heterogeneous disaster model cluster, a standardized web service chain publishing method is proposed.

  Results   Compared with the traditional isolated single disaster model, our method considers the complex chain relationship between different disasters based on the disaster chain theory and have the ability to provide multi‑disaster composite disaster simulation analysis function with higher flexibility, better scalability and stronger stability.

  Conclusions   The disaster chain rules provide a theoretical guarantee for the service chain orchestration method with strong flexibility and high intelligence. Besides, the main chain and the auxiliary chain are adopted to settle the problem of logic conflict caused by the circular structure of the disaster chain. Meanwhile, based on the QoS index evaluation system, the disaster model service chain optimization method and dynamic adjustment method are proposed to ensure efficient and stable response of distributed heterogeneous disaster model. In general, the proposed method can help realize the multi-hazard composite disaster situation analysis function and provide flexible, intelligent, and stable disaster analysis information to integrated emergency management.