Abstract:

To reduce disaster losses and save more lives， government departments and mobilization agencies need to provide emergency supplies to disaster areas through the emergency material mobilization chain. The emergency material mobilization chain may be affected by emergencies and derivative crises， resulting in significant disturbances or even disruptions in different segments. Multiple disruptions have complex and nonlinear coupling relationships， making it difficult to accurately quantify the risks and effectiveness of the mobilization chain system. Meanwhile， China’s 14th Five-Year Plan for National Emergency System proposes enhancing resistance to damage and rapid recovery under extreme conditions. Therefore， clarifying the internal coupling mechanism of multiple disruptions and finding a recovery mechanism for the emergency material mobilization chain has become a practical problem that needs to be urgently solved by all sectors of society.

The existing literature on disruptions management is mostly based on the enterprise level and static perspective， with a gap of research from the government level and overall control over the dynamic perspective. In addition， current research on emergency material mobilization has not taken into account the degree of damage caused by multiple disruptions. At the same time， huge emergencies not only cause demand or supply disruptions， but may also affect the normal operation of the mobilization chain， disrupting communication between some management departments， and ultimately causing organizational disruption. How to provide recovery strategies for emergency material mobilization chains in such disruption events is still rarely discussed. The optimization mechanism of emergency material mobilization chain resilience under the coupling of multiple disruptions is even rarer.

Aiming to address this problem， the evolution and coupling mechanisms of various disruption events are sorted out， when demand disruption， supply disruption and organizational disruption happen simultaneously. Then， the system dynamics model of the emergency materials mobilization chain is established under the coupling of multiple disruption events， considering the restoration process of each subsystem and the mobilization magnitude of the supply agents. The relief tents case in Zhejiang Province during 2008 Sichuan earthquake is used to simulate the resilience value of the emergency materials mobilization chain in continuous time. How to adjust the key variables to enhance the emergency materials mobilization chain resilience is explored.

Several key findings are proposed. When multiple disruption events are coupled， restoring the damaged subsystem can improve the mobilization chain resilience， but the resilience is still lower than the ideal state. Improving the level of restoring mobilization of each subsystem can speed up the recovery of mobilization chain efficiency at the beginning of the task， but its influence will decrease at the end of the task.

The impact of disruptions on the emergency management department is measured and restorative measures for buildings， roads， and information systems are introduced to explore the effect of various recovery strategies on the mobilization chain resilience. These works have not been discussed by previous researchers， which can help the practitioners to put forward improvement measures for the bottlenecks in time， so as to provide scientific reference for the practical work.

Key words: emergency material mobilization chain, disruption event, resilience, system dynam