[1] [1] Luo Ali, Zhao Yongheng, et al. Research in Astronomy and Astrophysics, 2015, 15(8): 1095.

[2] [2] Schierscher F, Paunzen E. Astronomische Nachrichten, 2011, 332(6): 597.

[3] [3] Hampton E J, Medling A M, Groves B, et al. Monthly Notices of the Royal Astronomical Society, 2017, 470: 3395.

[4] [4] Liu Chao, Cui Wenyuan, et al. Research in Astronomy and Astrophysics, 2015, 15(8): 1137.

[5] [5] Du Changde, Luo A, Yang H. New Astronomy, 2017, 51: 51.

[6] [6] Worthey G, Faber S M, Gonzalez J Jesus, et al. The Astrophysical Journal Supplement Series, 94(2): 687.

[8] [8] Chen T, Guestrin C. XGBoost: A Scalable Tree Boosting System. ACM SIGKDD International Conference on Knowledge Discovery and Data Mining. ACM, 2016. 785.

[9] [9] Gray R O, Corbally C J. Stellar Spectral Classification. Princeton University Press, 2009. 160.