Quality Check Methods For Sichuan 1:10 000 Digital Line Graphic

With the rapid development and wide application of mapping technology and GIS technology, the quality of the spatial data as an important component of GIS has become a research hotspot in the field of GIS both at home and abroad. The DLG data is currently the most basic and widely used spatial data in GIS, so the research of its quality check has important theoretical and practical significance.In the actual work of the relevant departments in China, although the production technology, data content and data format of DLG has changed, the examination work of DLG data products , to a great extent, is still using traditional methods and models till now, which directly leads to quality check's low precision and low efficiency. However, the current researches on the quality check technology of DLG are mainly focused on theory, and lean to final evaluation of data quality. In contrast, there are few researches on quality check method for DLG , and the quality check software with high quality and high automation is far less, so it is difficult to meet the demands of Basic Geographic Information Data's quality control and check work for mapping production and test departments.Therefore, researching on quality check technology of DLG in combination with actual production process and developing corresponding Spatial Data Quality Check System utilizing computer technology and GIS technology are imminent.The research of this text just launched because of this background, and the main contents are as follows:1. The concept of spatial data quality and the causes of spatial data quality problem are introduced. At the same time, the error of the spatial data is analyzed and the quality model is expatiated.2. Take 1:10 000 DLG data in Sichuan Province as an example, the data types, characteristics and production methods of DLG as well as the influencing factors of DLG quality are analyzed. A 1:10 000 DLG data quality model is established, and the quality check indexes are extracted based on this model, thereby the quality check contents and methods of 1:10 000 DLG are introduced.3. The automatic check algorithms for system quality indexes are discussed in detail, such as the maps junction, the lines intersect, plane position precision, attribute accuracy and so on, and a method on automatic batch quality check of maps junction problem is introduced.4. The investigation of user needs and analysis of relevant standards, technical regulations are done. And a 1:10 000 DLG quality check system is analyzed and designed, at the same time some system functions are shown.In sum, the DLG quality check model, contents and methods in this paper can be extended to other provinces' 1:10 000 DLG data quality check and related projects, which plays a certain role in carrying out quality check of mapping products.