Comprehensive Evaluation Of Hydrate Based On Object-Oriented

Comprehensive evaluation of hydrate is the primary aim for hydrate investigation,according to the experiences from hydrate exploration of these several decades.The datum of valuation indicators for hydrate comprehensive evaluation in the relational database is with characteristic of multi-source,heterogeneous,information isolated and the multi-scale in space,time and semantic.Therefore,it is worth to investigate the methods of displaying multi-scale characteristics by visualization and the methods of data interaction based on the object-orientated data model for identifying the latent knowledge in the multi-source heterogeneous datum,and this paper focuses on these issues.This paper studies data processing and analysis methods,BP algorithm,"self-learning" pattern recognition methods and the optimized BP algorithm,designs the process of optimizing the initial values of weights and thresholds for BP network and this process improves the efficiency and the accuracy of BP algorithm;and this paper also proposes the process of fusing the "self-learning" pattern recognition methods and the BP algorithm and this process solves the implicit limit of lacking samples for comprehensive evaluation.Ontology modelling idea is designed and the ontology model is constructed for hydrate comprehensive evaluation.This paper constructs hydrate comprehensive-evaluation businesses based on the hydrate exploration businesses analysis and data analysis.Designs business model constructing process based on business domain division-business division-business flow division – business activity division,and constructs the business model for hydrate comprehensive evaluation.Proposes ontology modeling process with the sequence of ascertaining the theme of business domain,ascertaining the classes or concepts in the scope of business domain,defining the hierarchical and inter relationships between classes or concepts,defining the properties of classes or concepts and their relationships and constructing cases;this paper designs the ontology model which contains the five basic elements as class or concept,property,context,operation and relationship,and constructs ontology model for hydrate comprehensive evaluation.This paper proposes the object-oriented model building flow as from business model and ontology model to business activity analysis,business abstracting,model integration,constructs object-oriented model for hydrate comprehensive evaluation.Implements the methods of object/relationship mapping,basic object/relationship mapping,incidence relationship mapping and the inheritance-system mapping based on the ideas of object relational mapping.Designs the multi-scale three-dimensional geologic modeling methods based on the vexel model,and segments the multi-source and different-accuracy datum into vexels with different scales based on the octree data management model,and constructs the multi-scale three-dimensional geologic model based on geocell model.The multi-scale three-dimensional geologic model of the Baiyun Sag is constructed using the available datum in this region.This paper designs and developed the hydrate comprehensive evaluation system whose architecture is composed of data layer,model layer and application layer,and this system contains the functions of multi-scale three-dimensional geologic modelling,model management and system application,and the multi-scale three-dimensional geologic models as visualization database can be used for data modeling and displaying within the different stages in the process of exploration and developing.Finally,these systematic methods are used for hydrate prospective evaluation within the 28 gravity-anomaly elements in the Baiyun Sag.