Evaluation of ambient air quality grade based on cloud model and combination weighting method

Aiming at the problem of air quality grade evaluation, an evaluation method based on cloud model and combination weighting method is proposed. The evaluation indexes and the pollutant concentration limits for each quality grade are determined according to the Ambient Air Quality Standards in this method. In addition, the construction method of grade standard cloud based on the the pollutant concentration limits for each quality grade and the modeling method of pollution state cloud based on monitoring data are proposed. Secondly, the problem of determining the index weight is studied, and the best and worst method combined with the linear combination weighting method is used to determine the index weight. Finally, with the help of the weighted average model, the grade membership vectors of each index evaluation were synthesized, and the comprehensive quality grade was determined. The results of the case analysis of air quality evaluation in Tianjin verify the effectiveness and advancement of the method.