A quantitative research on the classification of coronal mass ejections

It is widely accepted that the properties of coronal mass ejections (CMEs) depend strongly on their structure. Hence it is important, in the study of solar-terrestrial events, to classify CMEs of different morphologies according to intensity. The method of fuzzy comprehensive evaluation can be applied to quantitative research of the CMEs. The membership functions are determined according to previous statistical results and the correlations between the morphological properties and characteristic factors. By data reduction, three CME intensity categories, labelled strong, middle and weak, are obtained. The results show that the method using the fuzzy theory is better than the classic statistical analysis, especially for describing the middle importance category.