Memory Property of Grey Accumulation Generation Sequence

Figure 4

The memory of original AQI value and one-order accumulation value of three cities.

(a) The memory of original Beijing AQI

(b) The memory of 1-AGO Beijing AQI

(c) The memory of original Handan AQI

(d) The memory of 1-AGO Handan AQI

(e) The memory of original Xingtai AQI

(f) The memory of 1-AGO Xingtai AQI