| The storage and management of spatial data is a key feature by which GIS differentiate from other information systems. From file based model and database based model to the recent object oriented-relational database, the advancement of spatial data storage model powers the storage and management ability of GIS, Moreover, geodatabase physical model which shipped with ArcGIS8 software presents a brand new outlook of spatial data storage for geographic information systems. In GIS applications, the construction of geo-database can facilitates digitalization of basic spatial data, information based management and can help providing information service for the transfer and reproduction of basic geo-data, and help the industrialization of basic spatial data production. Nowadays, Object Oriented (OO) analysis and modeling technology becomes a powerful tool for spatial data simulation and management. This paper aims at examining OO modeling methods based on geodatabase, among which object oriented thinking methods are deeply applied. Data model provides a practical reference model in GIS project. Model urge GIS project in certain areas scrutinize project progress in a different angle. By designing data models in different areas, the application of GIS is accelerated and user can make their own GIS application starting from the template that model provides instantly. Spatial data model based on OO technology will becomes standard of spatial data management in application areas. Compared with the traditional data model which only emphasize data layers, OO data model will surely bring GIS a high efficient and flexible storage schema, and therefore bring great prospects to GIS. This paper examines the advanced technology in spatial data management methods from various aspects, delves into Object Oriented spatial modeling and the following Object Oriented database realization, A case study will help the research, the author drafts an urban road transportation data model as an example, under the support of ESRI's geodatabase storage model, this model displays many aspects of OO modeling, by Visio software, UML is used to define the model, and then use the Case tool in ArcGIS8 to help generate database schema, Finally, data is loaded to the database. In this paper, the author ranges topic from inherence, relations, topology, network, linear reference to multi-scale, domain and layer division. The paper is divided into five parts, The introduction section introduces the meaning, merit and current status of OO data modeling in spatial database construction, and outlines the objective of this paper; The second chapter discusses the theoretical basis of object oriented database and object oriented data model, then examines ESRI's spatial database physical model—geodatabase; The following chapter is about technological methods used in urban transportation model, the author conducts a comprehensive research on the key technology of OO; The forth chapter tells what the author did, an overall data model designing in the area of urban transportation is presented including the design process; The last part is conclusion and expectation.
|
PDF Full Text Request