Study On Quality Assessment And Control Of GIS Spatial Data

Quality is an important evaluation index of spatial data,which is of great significance to the effect of evaluation data in production and application,and the quality evaluation of GIS spatial data is a very important link in the production process of surveying and mapping products.At present,the quality evaluation of surveying and mapping products in our country is mostly limited to several commonly used methods.When evaluating the quality of GIS spatial data,the characteristics and applicability of these methods are not deeply understood.Based on the research and summary of the theory of spatial data quality evaluation,this paper focuses on several commonly used methods of spatial data quality evaluation,and analyzes the advantages and disadvantages of defect deduction method and fuzzy comprehensive evaluation method through the verification of examples.The main research contents of this paper include the following aspects:(1)This paper analyzes the concept and characteristics of GIS spatial data quality,and puts forward and explains in detail the influencing elements of GIS spatial data quality in combination with the quality inspection function requirements of the surveying and mapping results quality inspection integrated service system.(2)The quality evaluation system of GIS spatial data is comprehensively studied.This paper expounds in detail how to select the evaluation factors in the evaluation process,and comprehensively analyzes the evaluation models of data quality,then lists the corresponding spatial quality evaluation methods according to various quality models,and compares and analyzes the advantages and disadvantages of these methods on the basis of theory.(3)The quality control system of spatial data is comprehensively analyzed.This paper expounds the significance and principles of system data quality control,comprehensively analyzes the quality control methods of different types of spatial data,such as digital line drawing,digital elevation model,digital orthophoto map,etc.,and puts forward GIS data repair methods,which provide the basis for how to do a good job in spatial data quality control.(4)Taking the digital elevation model data in GIS spatial data as an example,different mathematical models are selected,and the defect deduction method and the fuzzy comprehensive quality evaluation method are verified by examples under the set three criteria.The research shows that when the fuzzy comprehensive evaluation method is used for evaluation,almost all quality information can be fully and reasonably utilized,the evaluation process is more detailed than the traditional defect deduction method,and the evaluation results are more scientific and reliable.However,in the process of defect identification,the defect deduction method has a better effect.