Comprehensive evaluation of urban air quality using the relative entropy theory and improved TOPSIS method

With the acceleration of economic development and urbanization, urban air pollution is becoming increasingly serious and has already affected the environmental and human health. Therefore, the detection and management of air quality is imperative. An accurate air quality evaluation can help people better understand and improve the air quality. In this work, a new multi-pollutant weighted comprehensive air quality assessment method combined with the relative entropy theory and improved order preference by similarity to the ideal solution (iTOPSIS) method is proposed. First, two objective weight methods are adopted to determine the degree of influence of pollutants on air quality. Then, a comprehensive weight is calculated using the relative entropy, which can measure the degree of similarity between the two probability distributions. Based on the calculated comprehensive weights, the air quality level is evaluated using the iTOPSIS method. Finally, the effectiveness of the proposed method is evaluated using an example. The results show that the proposed method can not only directly express the air quality level but also provide important and effective information for managers to use to control air pollution.