Research On Optimization Decision-making Of Emergency Scheduling For Rescue Teams Under Large-scale Geological Disasters

Large-scale geological disasters become the focus and difficulty of the research,due to their suddenness,destructiveness,time urgency,high uncertainty,derivative and evolvement.Especially,over the past years,large-scale geological disasters represented by earthquakes and giant landsides have frequently occurred in various countries and posed a serious threat to the life and property safety of human beings.Therefore,it is an urgent issue that how to effectively respond these irregular emergencies has been proposed as a critical issue faced by the whole society.When a large-scale geological disaster happens,the critical issues are how to immediately respond and develop rescue teams schemes and schedules to save human lives and relieve and control the damages.However,the current research mainly focuses on the scheduling and allocation of relief supplies,which neglecting the effect of rescue teams.In reality,many geographically-dispersed areas in disaster impact zones require immediate action by rescue teams because these areas are under time pressure and are suffering severe resource scarcities.Besides,many volunteer rescue workers who rushed to the disaster site created chaos and disorder,which resulted in even more problems.Therefore,one of the most critical emergency rescue tasks is the efficient allocation and scheduling of rescue teams.In this context,this work concentrates on the optimization decision-making of emergency scheduling for rescue teams under large-scale geological disasters and aims to develop some decision-making tools and models by resolving many difficulties in the emergency rescue process,to assist the dynamic real time emergency response and improve the response capability to handle such unpredictable extreme events.This research adopts a problem-solution approach with three steps that problem recognition,problem definition and problem solution.In the view of problem recognition,the unique characteristics of large-scale disasters are identified.Then the corresponding challenges posed on emergency response decision-making are analyzed from the perspective of studying problem definition.Finally,some operational research models are developed to capture the essential features of rescue teams scheduling,and attempt to provide a solution to bridge the gap between what emergency response should do and how to do in practice.In details,the studying works focus on five parts given below.Firstly,this dissertation investigates the emergency rescue teams scheduling problem to coordinate the conflict between disaster severity and complexity of rescue teams.In this part,a collaborative filtering mechanism is used to characterize the differences between rescue teams and the affected areas.Then the model considers two objectives of promptness and high efficiency to schedule the most suitable rescue teams to affected areas in the shortest time,which better describes the emergency rescue decision-making of large-scale geological disasters.The results show that collaborative filtering mechanism can effectively reflect the characteristics of the rescue team and realize the personal scheduling of rescue teams.In addition,large-scale geological disasters can easily cause road network damage in the affected areas,so choosing helicopters as the main transportation tool in the disaster areas can effectively improve emergency rescue effect.Secondly,this dissertation explores the scheduling strategy problem to capture the multiple competing demands faced after the large-scale geological disasters.The rationality of the scheduling strategy is measured from the priorities of rescue teams scheduling and the fairness of affected areas.Therefore,three priority scheduling strategies are defined according to the burden-benefit accord principle;a disaster priority strategy,a distance priority strategy,and a balancing of the disaster and distance strategies.Then an integrated model is developed to combine the rescue depots selection and rescue teams scheduling.The results show that a priority scheduling strategy is better than a strategy without priority considerations;however,which of the three priority strategies is most appropriate for a specific disaster situation depends on the maximum rescue time allowed by the disaster.This study provides an effective decision-making tool for balancing the competing demands among various affected areas and a basis for the decision-making of rescue teams scheduling strategy under different disaster situations.Thirdly,this dissertation develops a multistage scheduling model for rescue teams to dynamically respond to the disaster chain.According to the theory of disaster evolution,this part studied the multi-level linkage response mechanism in the process of deployment of rescue teams.Once a secondary disaster occurs,the model becomes a multistage scheduling problem,which will update the supply and demand information of various resources to regenerate a new emergency scheme,and the model can be extended to cover additional secondary disaster situations over the life of the disaster chain.Finally,the experimental scenarios results indicated that the overall performance of the proposed method was satisfactory in comparison with current method regardless of whether the secondary disasters occurred sooner or later.Fourthly,this dissertation proposes a collaborative optimization method for rescue teams to solve the contradiction between the resource structure differences and competing demands in the rescue process of large-scale geological disasters.The studying efforts in this part are unfolded from three aspects.First of all,the conditions of coalition and resource sharing in the case of large-scale geological disasters are identified.And then,a collaborative multi-objective optimization model of rescue teams scheduling was developed based on the resource sharing mechanism,that is,the rescue depots cooperated in the form of coalition to share the resources.At last the results show that compared with the current research that rescue depots will be taken as an independent individual to carry out the scheduling decision,the proposed rescue teams collaborative optimization method can better realize the resource complementary advantages between rescue depots,realize the resource sharing,improve the utilization efficiency of resources and the effect of emergency rescue.Finally,this dissertation designs the corresponding non-dominated ranking genetic algorithm(NSGA-II)to solve the problem.The results verify the effectiveness of NSGA-II in solving this kind of problem.In order to eliminate the randomness of the algorithm,the reliability of the algorithm can be improved by C-METRIC index to select the optimal Pareto solution set.Combined with Subtractive Clustering and Fuzzy Logic,the hybrid optimization method can select an optimal trade-off solution from the Pareto solution set based on Pareto front distribution characteristics,which can directly assist managers in decision-making and improve the efficiency of emergency rescue.This method provides an effective solution to the final solution of multi-objective optimization problem.In summary,the research work provides an emergency decision-making tool to assist handling some essential problems in the process of rescue teams scheduling to responding a large-scale geological disasters.Innovation of this paper is mainly reflected in the following three aspects: First,the optimal scheduling strategy of rescue team is studied,which provides an effective method for decision makers to quickly determine the priority of resource allocation in the emergency rescue process of large-scale geological disaster to achieve reasonable allocation of limited resources.Second,a multi-level linkage response mechanism for rescue teams in the case of disaster chains is proposed,which provides a new way in response to the uncertainty of secondary disasters and the real-time scheduling decision of rescue teams.Third,a collaborative multi-objective optimization model of rescue teams scheduling is developed based on the resource sharing mechanism,which provides a means of dealing with the contradiction between the resource structure differences and competing demands in the rescue process of large-scale geological disasters.Specifically,the research achievements provide an effective solution to the complicated management problem of post-disaster emergency rescue decision-making,which is of great significance and application value to improve the efficiency of emergency rescue work and the emergency response capability of disaster.