【作者】 朱瑞云；

【导师】 周卫；

【作者基本信息】 南京师范大学 ， 地图学与地理信息系统， 2008， 硕士

【摘要】 基础地理数据在城市信息化建设中的作用日益突出,DLG(数字线划图)数据作为最重要和应用最广泛的基础地理数据,是城市信息化建设的重要的战略资源。大多数城市都进行了DLG数据的生产与建库工作,基本满足了城市发展需求,但城市DLG数据库在共享、管理和维护上存在一些问题,影响了数据资源的充分利用。空间元数据是实现空间数据共享,使数据充分发挥作用的重要条件之一,空间元数据描述了地理信息中空间数据集的内容、质量、表示方式、空间参考以及其它的特征,有助于空间数据的理解、发现、定位、挖掘、评估和维护。本文的研究目标就是通过探讨城市DLG数据库元数据的内容和组织方式,设计并开发元数据管理系统,提供城市DLG数据库元数据的建库、查询、发布与同步更新等功能,帮助数据生产单位更好的管理和维护DLG数据库。论文首先回顾了元数据研究的国内外现状,介绍了空间元数据的概念、作用和意义,简要论述了XML数据库等关键技术,并结合具体的应用需求,通过扩展相关元数据标准形成了城市DLG数据库的各类元数据方案,为下一步研究工作奠定了基础。然后,论文详细分析了空间元数据组织的复杂性与现有元数据组织方式的不足,并结合城市DLG数据库元数据的特点,提出了基于XML数据库以分级的方式组织城市DLG数据库元数据。围绕城市DLG数据库元数据管理应解决的几个关键技术问题,论文给出了一个空间元数据管理系统模型,同时对元数据库同步更新机制进行了深入探讨和研究。最后,进行了空间元数据管理系统的开发与实现,并对全文的研究工作进行了总结,指出了论文的不足和下一步努力的方向。更多还原

【Abstract】 The role of basic geographical data in urban informatization construction has become increasingly conspicuous. DLG data as the most important basic geographic data are important strategic resource for city’s informationization and are used widely. Urban DLG databases, which meet the demands from the development of the cities basically, have been built in most cities. The application of DLG data resource is affected by the problems of database management, maintenance and DLG data resource sharing. Spatial metadata, which describes the content, quality condition, representation, spatial reference, management and other data characteristics of the data contained a spatial dataset of geographical information, is one of the important conditions to making full use of spatial data resources by spatial data sharing. Using spatial metadata is an effective method to access, locate, evaluate, mine, understand and maintain spatial data. The objective of this thesis is to design and develop a metadata management system, which provides some functions such as building metadata database, querying metadata, updating metadata and publishing metadata for urban DLG database by researching on the content and organization mode of metadata of urban DLG database. The system can help the data production departments to maintain and manage the urban DLG database better.Firstly, in the paper, we review the status-quo on metadata research at home and abroad; present the concept, role and meaning of spatial metadata. The XML database technique is dissertated briefly. Facing to concrete application demand, the metadata schemas for different metadata of urban DLG database are formed by extending metadata related standards, laying the foundation for the future research work.Then, the organizational complexity of spatial metadata and the deficiency of existing organization mode for spatial metadata are analyzed in detail. The gradually organization of metadata for urban DLG database based on the XML database is proposed around the feature of metadata for urban DLG database. This paper gives a model of metadata management system for urban DLG database concerning several key technical issues that should be resolved. Meanwhile, an in-depth study on synchronous update mechanism of metadata database is made for urban DLG database.Finally, we implement a Prototype of such system. Also we have a conclusion on our work and propose the next to do.更多还原