Assessing And Selecting Emergency Suppliers From The Perspective Of Resilience Improvement

Under the attack of natural disasters,improving the capability of self-protection and self-rescue of a community is the key to efficiently minimize the loss of lives and property caused by disasters.Disaster resilience is universally defined as the ability of the disaster-stricken area to prevent,resist and recover from disasters with resources available to itself.However,the research on disaster resilience in the existing literature is limited to the interpretive meaning of its concept.The ultimate goal of resilience research is to figure out the strategy of improving the resilience level.Emergency resource scheduling,as a critical part of community self-rescue ability,will determine whether the disaster-stricken areas can timely mitigate the interruption risk of relief materials and recover to the status with continuously stable supply.Making backup plan is an effective measure to mitigate interruption and enhance resilience.However,very few studies focus on how to select emergency resource backup suppliers in humanitarian relief.Therefore,the problem is how to select backup suppliers from the perspective of improving the level of resilience of emergency resource scheduling under multiperiod disaster situation.Considering the circumstance that a multiperiod disaster attacks primary suppliers in the disaster-stricken area,such as earthquake,the decision-makers need to take defense measures to mitigate the interruption due to the loss of primary suppliers.A sequential game is formed to identify sets of primary suppliers whose loss results in worst-case cost of emergency resource scheduling,in which case defender figures out the optimal backup suppliers and identify critical primary suppliers.Firstly,based on Stackelberg game,an attacker-defender(AD)model is built to characterize the situation where a single-period disaster occurs and the defender does not adopt the pre-disaster defense strategy,from the perspective of improving resilience to the worst-case losses.With a numerical example,the relative level of the resilience is analyzed from both aspects of outcome and process of the game,in which the optimal backup suppliers is obtained.Secondly,based on AD model,a three-stage sequential game model of defender-attacker-defender(DAD)is built in the case of multiperiod attack of disaster and allowing the defender to take pre-disaster emergency supplies storage as defense strategy.This model is to assess the relative level of emergency resource scheduling resilience under the condition that both pre-disaster storages and backup suppliers are taken.The result identifies the critical primary supplier that affects the vulnerability of emergency resource scheduling and provides the optimal strategy of backup supplier selection,as well as reveals how pre-disaster storage selection affects the significance of different primary suppliers.Finally,the numerical analysis of this model is applied to the case of Wenchuan earthquake,which assesses the effect of different backup suppliers on improving emergency supply scheduling resilience,thus hopefully providing concise guide for decision-makers.