Application Of DUCG Based On Rough Set In Environmental Protection Evaluation

China’s rapid economic development has brought about some problems of ecological environment and social environment.The sustainable development of cities has become the focus of social attention,so the evaluation of urban environmental protection can provide corresponding suggestions for urban development.In this paper,rough set and Dynamic Uncertain Causality Graph(DUCG)theory are used to complement each other.It is applied to the evaluation of urban environmental protection,and reliable ranking results are obtained and corresponding suggestions are given.(1)Based on the three levels of natural environment,economic environment and social environment,this paper evaluates the environmental protection of 19 cities in China,including the first tier cities and the new first tier cities.Through the refinement of the indicators,16 indicators that meet the standards are selected to establish the indicator system.(2)According to the knowledge theory of rough set,the specific values of 16 indexes are collected from the statistical yearbook,and the decision table of urban environmental protection evaluation is established.Data are processed by equidistant scatter,then,through the idea of discernible matrix,the discretized data is reduced by the improved core searching algorithm,Leave 11 representative indicators and establish a new decision table.Finally,by the relative importance of each attribute to the decision attribute,the corresponding weight value of the condition attribute is obtained.(3)Based on the knowledge theory of DUCG,the establishment method of urban environmental protection evaluation model is described.First,the original DUCG evaluation model of urban environmental protection is established based on the logical relationship of 11 indicators,taking the indicator status of each city as the observed evidence E,the simplified DUCG model based on evidence E is obtained,taking the weight value of rough set as the action parameter,the final scores of each city areobtained by using the event expansion and probability reasoning of DUCG,and the scores of 19 cities are analyzed.Finally,compared with other common evaluation methods,the result is consistent,and overcomes that the traditional method is only the result of quantitative calculation.In this paper,the quantitative and qualitative analysis of the evaluation object is carried out,and the evaluation process is more concise and intuitive.(4)According to the results,Shenzhen,Guangzhou,Suzhou and Nanjing ranked high,From the natural environment,economic environment,social environment three aspects continue to improve the city’s environmental protection;Chongqing,Xi ’an,Shenyang and Kunming ranked lower,giving priority to economic development to drive other areas of development.Finally,the purpose of improving the sustainable development capacity of the city is achieved.