1, Class T: special periodical papers, which refer to papers published in Science and Nature; Class A: authoritative core journal papers, which refer to internationally accepted SCIE, EI, ISTP, SSCI, A &；; Papers included in HCI retrieval system 3, Class B: important core journals, referring to papers published in foreign core journals. 4. Class C: general core journal papers. 5. Class D: Papers published in general public journals refer to papers published in domestic public journals. 6. Class E: Papers published in restricted journals refer to papers published in domestic journals whose distribution is restricted.