Abstract: A dynamic evaluation method is proposed, in order to compare multiple systems at different times. According to the advantage and disadvantage of TOPSIS and gray correlation degree, the integrated closeness is proposed based on Euclidean distance and gray relational grade, it can reflect the trend relationship and situation relationship well between the alternative and the ideal alternative, the alternative and the negative-ideal alternative. The two-dimensional data with time series data is extended to three-dimensional data. Dynamic evaluation method based on TOPSIS and Gray Correlation Degree is put forward. The method takes into account the evaluation index values difference degree and the evaluation index values growth degree and this method can get the evaluation values and ranking results of the evaluation objects at a certain time and the overall evaluation values and sequencing results of the evaluation objects at a period of time. The ecological benefits of circular economy in Chinese east provinces regions in "the 12th Five Year Plan" period were evaluated by using dynamic evaluation method based on TOPSIS and gray correlation degree. The source data of the evaluation indicators come from Chinese statistics yearbook. Such an evaluation, as an instance, shows that the findings of this work are practically effective. The method proposed in this study provides an idea in dealing with dynamic evaluation, helpfully complements the comprehensive evaluation method, and facilitates the researches in related fields.

Key words: TOPSIS, gray correlation degree, dynamic evaluation method, three-dimensional data, circular economy