Analysis of cardinal grey relational grade and grey entropy on achievement of air pollution reduction by evaluating air quality trend in Japan

The Japanese government has promoted a number of policies regarding air pollution control to regulate the maximum permissible limits of air pollution, including motor vehicles, industrial activities, and firecrackers exhausts, which can be established as a mechanism for monitoring air pollution. Studies of Japan's air pollution have been presented since the 1970's, but only few studies have focused on evaluating air quality trend by grey system,...