Research On The Methods Of Emergency Resources Layout And Scheduling In Time-varying Semantic

In recent years,due to enormous pressure of population,social and economic activities have become more and more frequent.Natural resources over-exploited,global climate conditions deteriorating,floods,earthquakes,tsunamis,terrorist attacks,war and other natural disasters,man-made disasters and ecology disasters caused incalculable loss to human society.China is one of the countries most affected by disasters with many types of disasters,high frequency of occurrence,and extremely serious safety situation.In order to reduce the damage caused by disasters,timely emergency rescue is particularly critical.Resources supplies paly an important role in emergency rescue.The level of emergency resources layout and scheduling is directly related to the efficiency of rescue work.How to optimize emergency resources layout and scheduling in scientific and rational way is great significance to emergency rescue.As the factors affecting the layout and scheduling of emergency resources have characteristics of micro time-varying and macro time-varying,it is necessary to study thetime-varying analysis method of emergency resources layout and scheduling in order to improve emergency rescue capability.On the basis of extensive reading of research results of emergency resources layout and scheduling both at home and abroad,this paper summarizes shortcomings of the three key technologies:spatio-temporal data model,emergency resources optimization layout and emergency resources scheduling,for providing efficient and feasible methods and models of emergency resources layout and scheduling by carrying out in-depthstudy.This paper analyzes the process of emergency resources layout and scheduling,and constructs emergency resources layout and scheduling spatio-temporal data model supporting expression of spatio-temporal process.Based on the spatio-temporal data model,time-varying analysis of emergency resources optimization layout,network reliability and emergency resources scheduling are carried out.The research of this paper improves emergency rescue system capability,specific research as follows:(1)This paper analyzes the characteristics of requirements to emergency resources layout and scheduling,constructs emergency resources layout and scheduling spatio-temporal data model supporting expression of spatio-temporal process.Aiming at the process of emergency resources layout and scheduling,the characteristics of the elements and element features related to emergency resources layout and scheduling are analyzed.On the basis of analyzing spatio-temporal process,conceptual model of emergency resources layout and scheduling is constructed.Based on conceptual model,logical spatio-temporal predicates are introduced,and network semantics of node connectivity and stability are extended to construct the spatio-temporal logic model of spatio-temporal integration emergency resources scheduling.Taking spatio-temporal process of earthquake as an example,spatio-temporal data model of earthquake is constructed.The spatio-temporal process is expressed by graph theory and tuple,and the semantic query is enhanced to verify the feasibility and practicability of the model.(2)Based on the actual demands of the emergency resources layout,considering micro time-varying and macro time-varying feature of emergency resources layout,combined with emergency resources layout and scheduling spatio-temporal data model,the paper establishes emergency logistics center location model and emergency resources allocation model in preliminary,midddle and later term.The models aims at minimized travel time,maximized traffic convenience and stability,taking into account emergency tasks of each emergency stage.The initial stage is divided into spatial optimization layout under sufficient supply and spatial optimization layout under insufficient supply,which are restrained by total delay time and time emergency satisfaction respectively.The middle-late emergency stage is divided into emergency cost,total delay time,and spatial optimization layout with emergency cost and total delay time.Each logistics center meets all level resources demands in the initial stage of emergency resources allocation model if supply is sufficient,Otherwise,every logistics center only meets the first level.In the middle and late,each emergency logistics center supplies resources to its first emergency response level,and for non-first emergency response level resources needs,which are assigned to the logistics center matched to emergency aims.Ant colony algorithm is used to solve location model,and algorithm process is designed.The use of Pareto update rules can greatly reduce the priori knowledge dependency on multi-objective optimization problems.The introduction of elite files increases the exploratory nature of the algorithm and accelerates global non-inferior solution search speed.An example is given to illustrate the proposed model and algorithm.The results show that the proposed model and the algorithm can solve the problem effectively.(3)This paper analyzes the current situation of reliability research of transportation network.Based on the basic principle of GO method and emergency resources layout and scheduling spatio-temporal data model,this paper proposes a method of time-varying network reliability analysis based on GO method.Five operation signs are used to build the traffic network GO map,and the operation signs are extended.The method of translating nodes and arcs in the time-varying network into GO graph components is given.The practicality and validity of the method are verified by an example.(4)Based on the actual demands of emergency resources scheduling,considering the characteristics of micro time-varying and macro time-varying,the mathematical model of different emergency resources scheduling stage is constructed by combining emergency resources layout and scheduling spatio-temporal data model.In addition to minimized travel time and maximized reliability of the scheduling path,different goal is added to the model at different stages.For the emergency resources dispatching under sufficient and insufficient supply of the initial stage,minimized total time delay and the satisfaction degree of the quantity of emergency resources arrived and the time of arrival emergency resources are added respectively.In the middle and late period of emergency resources dispatching,the aims of minimized emergency cost,minimized total delay time with minimized total time delay are added The model solves the problem of multi-supply points,multi-demand points,multi-resources types and multi-resources supply points for allocation of resources for multiple resources demand points.Ant colony algorithm is adopted to solve the model.The issue is decomposed into emergency resources allocation and dispatching line planning.Emergency resources allocation ant colony system and emergency resources dispatching line planning ant colony system are designed respectively,and the two ant colony systems are calculated in parallel.For different emergency stages,different heuristic information is designed to the two ant colony systems,which improves the efficiency of ant colony optimalsolution.An example is given to validate the model and the algorithm finally.Research,test and application indicate that the research method of spatio-temporal data model from the business field of emergency resources scheduling is feasible.It can effectively solve the problem of poor practicality of current spatio-temporal data model.On the other hand,the method of time-varying emergency resources allocation,time-varying network reliability analysis and time-varying semantic path planning proposed in this paper providetheoretical reference and application reference to spatio-temporal model of the emergency resources scheduling and further research.