The Research On Method Of Geospatial Model Sharing And Interoperation

With the development of the smart city,as a kind of important decision resources,the demand for geospatial models is growing and complicated.In particular,the concept of model web is put forward and the unceasing development,the geospatial models as an important part of the model web should be given considerable attention.Model web is a dynamic network of numerous calculation models,its goal is to enable the user and modeller to access and operate the model and the model results through the web services of the standard protocol.However,at present,the geospatial models used for the decision-making of the smart city have different types,structures,developing modes,representation methods,inputs,outputs,modelling languages,modelling environments and service interfaces.At the same time there are a lot of repetitive constructions.When facing with a specific emergency decision,it cannot find the suitable geospatial models accurately,comprehensively and timely.The direct result is inefficiency to emergency response decision making.Thus,to realize the heterogeneous,massive and distributed geospatial models's sharing management and quickly,accurately discover and invoke available geospatial models is the goal of this paper,and to improve the efficiency of complex geospatial decision.In view of the characteristics of geospatial models and its low efficiency application in the city-wide decision-making process,this paper points out that the geospatial models sharing management and interoperation is a basic problem for smart city emergency decision-making.To solve the problem,the research is to lay the foundation for the realization of the geospatial model sharing and interoperation for the emergency decision-making in smart city.First of all,this paper summarizes the existing geospatial information exchange standards and related metadata standards,and analyzes the sharing requirements of geospatial models in the web environment.Through the expansion and reuse of existing metadata standards related to geospatial information,the paper proposes an eleven-tuple metadata model for geospatial model sharing.By adopting the MOF meta-model theory,this paper establishes the nested sharing of geospatial models of resource description model,to facilitate unified modeling,registration,discovery,combination and management of geospatial models by providing basic information model in the web environment.Secondly,based on the CSW specification of OGC,this paper proposes modeling and register mechanism through the geospatial model resource description model.Through the expansion of the core information model of CSW,the geospatial model registry information model is established;through the mapping form the geospatial model resource description model to registry information model,it can achieve the geospatial model's CS W standard registration,and provide the foundation for the following geospatial model's discovery and composition.Again,based on established geospatial model directory service center,design fine-grained,multi-level geospatial model metadata query terms.Through the CSW discovery interface,it can realize the demand to discover the geospatial model resources.Based on the geospatial model resource description model and model discovery method,the paper proposes a method for the geospatial model combination.Through constructing the geospatial model chain,it can solve the complex decision problem which cannot be solved by a single model.Fourthly,based on the technology and methods proposed above,the paper constructs the geospatial model service architecture and designs the geospatial model service interfaces,including the model modelling service,model registering service,model discovery service,model combining service,model executing service and so on,to facilitate geospatial models' sharing and interoperability in the web environment.Finally,this paper builds the distributed geospatial model sharing management platform framework.By using the city shortest path analysis decision-making and city fire emergency decision-making as the experimental resources,the paper verifies the validity and feasibility of the shared management model and method.