顾及语义差异的基础地理信息客户数据库更新实施模型

Fundamental Geo-information Client Database Updating Model Considering Semantic Heterogeneities

客户数据库更新就是利用新版基础地理数据库中更新变化的要素信息,对客户数据库进行相应的级联更新,以使其具有良好现势性的过程。现有研究大多侧重于基础地理数据库更新信息的分发与提供,而没有充分考虑语义差异环境下如何高效实施客户数据库更新的具体问题。针对此,该文概括了基础地理数据库与其客户数据库之间潜在的各种语义差异;从实施效率、数据完备性、一致性、正确性等方面,分析描述了语义差异给更新实施过程带来的不利影响;最后依据语义映射和转换理论,提出了由语义匹配、变化提取、更新集成3种基本操作组成的更新实施模型,并阐述了3种基本操作的执行策略和关键环节。

Client database updating refers to the process of utilizing the related information of the changed and updated features in the new version of fundamental geographical information database to perform the corresponding cascade updates on client database for ensuring it also has good currency.The current researches emphasize particularly on the distribution and delivery of updating information,but how to efficiently implement the updating of client database,especially in the case of semantic heterogeneity,doesn′t be considered fully.Aiming to this problem,the semantic heterogeneities between two databases are firstly summarized,and then their impacts on the updating implementation process are described from some aspects such as efficiency,the completeness,the consistency and correctness of data.Finally,the updating implementation model consisted of three basic operations,semantic matching,updates extraction and updates integration,is proposed according to the theory of semantic mapping and transformation,and the execution strategies and key steps of these operations are respectively discussed.Through these discussions and analysis,the concept of fundamental geo-information client database updating,its implementation requirements and technical difficulties,the corresponding solutions,the key problems needed to be further researched are made clear.Based on the current works and the future researches,an automated and efficient software tool for client database updating is promising to be developed and realized.