1. Environment Research Institute, Shandong University, 250100 Ji’nan, China
2. State Environmental Protection Key Laboratory of the Cause and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, 200233 Shanghai, China
3. Key Lab of Geographic Information Science of the Ministry of Education, School of Geographic Sciences, East China Normal University, 200241 Shanghai, China
4. Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, 999077 Hong Kong, China