[1] Tang Jingtian, Li Jin, Xiao Xiao, et al. Mathematical morphology filtering and noise suppression of magnetotelluric sounding data[J]. Chinese J Geophys, 2012, 55(5):1784-1793. (in Chinese)
[2] Chen Leshou, Wang Guang'e. Magnetotelluric Sounding Method[M]. Beijing:Geological Publishing House, 1990. (in Chinese)
[3] Tang Jingtian, Xu Zhimin, Xiao Xiao, et al. Effect rules of strong noise on magnetotelluric (MT) sounding in the Luzong ore cluster area[J]. Chinese J Geophys, 2012, 55(12):4147-4159. (in Chinese)
[4] Li Jin, Tang Jingtian, Xu Zhimin, et al. Magnetotelluric noise suppression base on signal-to-noise identification in ore concentration area.[J]. Chinese J Geophys, 2017, 60(2):722-737. (in Chinese)
[5] Ye Hua, Tan Guanzheng, Li Guang, et al. De-noising nonstationary signal based on sparse representationand particle swarm optimization[J]. Infrared and Laser Engineering, 2018, 47(6):0626004. (in Chinese)
[6] Ye Song, Li Yuanzhuang, Sun Yongfeng, et al. Extraction of spatial heterodyne spectroscopy target based on empirical mode decomposition and regression analysis[J]. Infrared and Laser Engineering, 2018, 47(12):1223001. (in Chinese)
[7] Ye Hua, Tan Guanzheng. Manifold learning of depth label for single image[J]. Infrared and Laser Engineering, 2018, 47(6):0626004. (in Chinese)
[8] Liu Xinji. Dilaton and erosion for geoscience-data sets[J].Computing Techniques for Geophysical and Geochemical Exploration, 1988, 2:105-113. (in Chinese)
[9] Liu Dongsheng, Li Yuan, Yang Wenbo, et al. Bearing fault diagnosis based on adaptive multi-scale morphological gradient and non-negative matrix factorization[J]. Journal of Vibration and Shock, 2013, 32(19):106-110. (in Chinese)
[10] Li Bing, Gao Min, Zhang Xuguang, et al. Gear fault diagnosis using morphological gradient method and non-negative matrix factorization[J]. Journal of Vibration,Measurement Diagnosis, 2014, 34(2):295-300. (in Chinese)
[11] Li Peng, Li Hongru, Xu Baohua. Performance degradation feature extraction method based on mathematical morphology gradient spectrum entropy and its application[J]. Journal of Vibration and Shock, 2016, 35(16):86-90.(in Chinese)
[12] Rodi W, Mackie R L. Nonlinear conjugate gradients algorithm for 2-D magnetotelluric inversion[J]. Geophysics, 2001, 66(1):174-187.