Research Of Urban Land Grading And Evaluation Information System Based On ComGIS

It has been one of very important missions of current land management to evaluate the grades of land quality synthetically with our country's economy developing rapidly and the policy of compensated land-use putted into effect. The GIS technologies which center on the techniques of spatial data management and synthetic cartography provide ideal technological means for the informationised construction of the system of land grading and evaluation, so the means completing the works of land grading and evaluation have changed from traditional manual means into scientific, quantitative, automatic means gradually, so that the artificial influence on the works is diminished and the use value of the achievements is intensified, and the progress of modernization of the means completing the works of land grading and evaluation is accelerated.In small and medial cities there are many problems need to be solved such as it usually takes too much evaluating time in the works of land grading and evaluation, the conditions of standard are not identical, the connotative meaning is ambiguous and the accomplishments are expressed indirectly. In order to solve these problems the system of land grading and evaluation is researched and constructed with technology of ComGIS in a certain medial city in the thesis. The research is meaningful to accelerate the reformation land-use policy, modernize and informationize land management.The research contents of the thesis are as followings:â… . On the basis of generalization and analysis of the mathematic models of land grading, the grades of land are grading with the techniques of factor-weights and calculating the gradation-profits (the method of grading by market price). Those are used to calculate reference land-price, the articles of land-profit and kinds of articles of market transactions. The modernization, informationization and visualization of land grading and evaluation are realized through combining the model with GIS.â…¡. Those are two of important influential factors to land grading, the degree of prosperity of commercial zone and the degree of road access. How to realize the two factors with the algorithms of GIS is explored in this thesis, and the spatial analysis is carried out combining the actual situations of the research zone. â…¢.The grade graph and the isoline graph are made with the functions of spatial analysis and cartography of special thematic cartography of GIS, the scope of each grade is also optimized. The grade graphs of synthesis, commerce, habitation, industrial land-use, and the general weight graph of land grading of urban zone, and the weight graph of evaluating factors, and so on, are made with the classifying evaluation grade method.â…£.The general system design is carried out according to the system object. The main functions of the system of land grading of a certain city are realized with the C/S structure, the technology of ComGIS and SDE. Those functions include the basic graph operation, information inquiry, statistical analysis of assessing situation, special thematic cartography, etc.