Retrieval Mechanism Of Ontology Sem Antic Similarity Principle In Case Based Reasoning Of Highway Engineering Cost

Highway engineering cost management is the focus of attention in highway construction activities,especially the accuracy of project estimation has great influence on the whole project.Case based reasoning is applied to calculate the cost of newly built projects,improve the accuracy of measurement and compilation,and play the role of auxiliary prediction.The core of this method is to select similar completed historical cost information.In order to quantify the similarity between cases,we use the principle of ontology semantic similarity in computer field to do interdisciplinary application research.Based on the existing theoretical system,this paper confirms the feasibility of building ontology in the field of highway engineering cost.The basis of ontology semantic similarity calculation is domain ontology structure diagram.In order to achieve this goal,we need to construct the domain ontology.According to the previous research results,the author selected the corresponding term concept,established the attribute index system adapted to the ontology structure,and realized the highway engineering cost domain ontology by using the Protege 5 software.Then the dynamic,combined and hierarchical retrieval mechanism is designed,and the semantic similarity calculation method based on three principles of path distance,information quantity and attribute are selected and improved,and the similarity calculation process of highway engineering cases is determined.Finally,the actual cost of two sets of cases is verified,and the effect is good.The research results show that the main body of the road engineering cost domain is composed of the existing standard theory system,the attribute index system and the actual highway engineering case.The generated ontology structure network diagram conforms to the principle of the construction of the ontology.In the retrieval mechanism,the three similarity calculation methods are based on the conceptual logic relation of the ontology structure network diagram,thus quantifying the degree of casesimilarity,and the error of the theoretical calculation results is within the scope of the existing calculation precision.The article focuses on the research of the road engineering domain ontology and case retrieval mechanism,which is the perfection and extension of the cost case reasoning,and provides new theoretical support for the application of the historical data of the highway engineering and the construction project.