Research On GIS Data Model

The data model is the bridge that link the real world with the data, which simulates simply the real word, which is a concept about the spatial entity in real world and the relation among them, which supply the basing method which is used in describe the structure of spatial data and designing the database mode. So it is very important to design spatial database and develop new GIS that studying and making research on data model. The control of data quality is also one of the most popular issues. Under the same software and hardware, whether the quality of data is good or bad will decide the quality of outcome what system analyzed, even whether the application can success or fail. It is used widely in every field that the analyses method of spatial data which are supplied by GIS system. The quality of data that is used in the field of decision-making must meet the corresponding demand. The standard on data quality may be deduced on the research on data model, error propagation law and the application object. So the research on data model has instructing and positive influence on spatial data quality evaluation and control.The paper mainly discusses the data model of GIS, data structure and software programming from the angle of data quality checking and evaluating based on the GIS data check and evaluation software system. Firstly, the paper introduces the 4D digital surveying and mapping products. At the same time, the paper also relates the concept that is related to controlling and the technology which man evaluate the spatial data quality on. And the background and significance of the software system is also discussed. Besides, the paper also discusses the design scheme of the software system which is made of five functional module, which includes data input module, data display module, data estimating module, report output module and the module which manage the type of error. And the system math model is also put forward.The paper mainly discusses the data model and the data structure of the document of the software system. The simple data structure of vector model is introduced using the ORACLE SPATIAL as an example. As for topology data structure of vector model, it is also discussed using E00 data file structure. The data structure that was created based on the feature on data checking and evaluating work by author is introduced and is one of the utmost innovation points of the paper. The data structure doesn't only deal with the data with simple data structure but also...