Research On Line Features Quality Assessment And Multi-Scale Water System Matching Method

With the progress of the times and the development of geographic information industry,concepts such as digital city and smart city are deeply rooted in people's minds.In order to comply with the development trend of the times,China is also making greater efforts to build digital cities.The basic geographic database is the basis of digital cities.If digital cities want to achieve better development,they must build basic geographic databases.However,there are differences between different databases and the current situation of databases cannot be guaranteed.It is unavoidable to integrate,fuse,and update databases,with the key technology of quality evaluation and target matching.So,it is necessary to study the related technology of quality evaluation and target matching.Specifically,the main research contents and innovations of this paper are as follows:(1)Aiming at the shortcomings of the existing line-line similarity calculation methods,such as poor calculation accuracy and difficulty in calculating the partial similarity,an improved line-line similarity calculation method is proposed.This method first insert vertexs to the polyline using the same distance,and then creates a grid index for all the vertexs of the polyline,and next,taking the distance and direction geometric indicators into account,calculate the set of similar arc segments,and finally,the length of all the similar arc segments are added to get the total similar length.(2)The evaluation of the positional accuracy of lines is an important content of line quality evaluation,and the accuracy of the existing line position accuracy evaluation methods is often low.This article uses a combination of improved line-line similarity calculation methods and the existing line-line similarity calculation method to evaluate the position accuracy of lines.The combination of similarity calculation methods can effectively avoid the shortcomings of each algorithm and make full use of the advantages of each algorithm,which can get better quality evaluation results.(3)The existing length integrity calculation method does not take the actual meaning into account.In this paper,based on the previous defect,an effective length integrity calculation method is proposed to evaluate the length integrity of lines.This method first uses the line similarity algorithm to calculate the similar length of all lines,and then calculates the ratio of the similar length to the sum of the length of all lines in the reference data.(4)Existing water-system matching algorithms and strategies have poor adaptability in combination of multiple geometry types and part-matching,and lack of consideration for the special conditions that occur in the matching process.This paper improves the sequence of target similarity calculation in water system matching,optimizes the algorithm and strategy of multi-scale water system matching,which improves the matching accuracy,and uses the buffer of the line to replace the minimum circumscribed rectangle of the line to build a candidate matching set,greatly reducing the search scope.