Research On Emergency Location Selection And Allocation Problem Considering Risk Utility Under Uncertain Environmen

China is experiencing an increasing trend of extreme heavy rainfall events due to the impact of climate warming.At the same time,the accelerated urbanization process has led to a sharp increase in the risk of floods and waterlogging disasters,which has had a serious impact on social and economic development and people’s production and life.At this time,"Disaster Management" has attracted widespread attention.Pre-disaster preparation is crucial to improve the response efficiency of emergency events and reduce the workload of post-disaster emergency compensation.How to select appropriate locations for emergency facilities such as distribution centers,medical centers,shelters,etc.before disasters are also an important research direction in disaster management.At the same time,after the disaster,if the material support is not timely and the distribution efficiency is low in the emergency rescue process,which leads to the failure of the victims to get effective relief in time,it will bring more serious losses.While strengthening the pre-disaster preparation work,it is also necessary to consider how to improve the scientific and efficient allocation of emergency supplies after the occurrence of urban emergencies in China,and minimize various social risks and possible problems.Therefore,this article aims to solve the joint optimization problem of emergency facility location selection and emergency material allocation.Firstly,this paper scientifically evaluates the disaster risk factors that need to be considered in the pre-disaster preparation work,constructs the regional relative flood risk assessment system,screens the indicators based on machine learning,and uses multiple multi-attribute decision-making methods to rank the flood risk of each region,and aggregates the flood risk ranking.Secondly,considering the three-level network structure composed of "Distribution Center-Shelter-Disaster-affected Point",based on the flood risk assessment,a shelter location model is established under the pre-requisition system: taking the proportion of the evacuated population at each disaster site as a random variable,a multi-objective mixed integer random programming model is established with the objectives of the shortest distribution time and evacuation time,the least number of people not evacuated in time,the minimum disaster risk and the minimum compensation paid by the government;according to the high-dimensional characteristics of the model,a multi-objective artificial bee colony algorithm based on cross mutation is designed to solve the model.Thirdly,considering the two-level distribution network from multiple distribution centers to multiple demand points when the location of the refuge is known,the prospect theory is integrated into the scheduling problem,and the risk perception function is established to describe the psychological risk perception of the victims.In the view of the uncertainties existing in the early stage of emergency,when the data is difficult to obtain,the estimated values of the parameters are obtained through expert estimation.Considering its subjective uncertainty,the uncertain variables are introduced to describe them.A multiobjective mixed integer uncertain programming model is established to minimize psychological risk perception and maximize time satisfaction of victims and the deterministic equivalent form of the model is obtained based on uncertainty theory.The model is solved by designing an improved artificial bee colony algorithm.Finally,Nanjing is selected as the study area to evaluate the relative flood risk in different areas of Nanjing.Based on the evaluation results,the location results of pre-requisition shelters in different areas of Nanjing are calculated.Based on the location results,the multi-cycle emergency supplies distribution plan is calculated.The analysis proves that the model can effectively control transportation costs while considering timeliness,fairness and psychology of the victims.Decision makers can choose their attitudes towards cost and psychological loss of victims through different combinations of decision preference coefficients,so as to form a multi-period emergency supplies distribution plan.This paper introduces disaster risk,the psychological risk perception of disaster victims and other factors into the optimization of emergency facility location and emergency material allocation.Considering the characteristics of various uncertain factors,a systematic optimization model from pre-disaster location to post-disaster emergency material allocation is established under the uncertain environment,and the key problems in each stage are analyzed,aiming at solving weakness in the current disaster emergency optimization decision-making,It is hoped to provide new research ideas for the scientific location of pre-disaster emergency facilities and the scientific,efficient and fair distribution of post-disaster emergency supplies,and provide theoretical and decision-making reference for relevant decision-makers in emergency management decision-making.