Multi-factor degree set pair analysis fuzzy model to evaluate lake water quality

Considering the fuzzy feature in assessment, The set pair analysis has been developed by the concepts of the main same, supper same, assimilation degree and the new grades law. The multi-factors degree set pair analysis fuzzy evaluation model has been established and been applied to evaluate the water quality of lake in West Lake and Qinghai Lake. The results show that new evaluation method is feasible and can effectively evaluate water quality of level.