When using near-infrared reflectance spectrum to identify coal gangue. the change of detection distance between spectrum acquisition device and working face and dust interference will affect near-infrared reflectance spectrum. In order to select the best pre-processing method for near infrared reflectance spectrum for coal gangue. samples of anthracite and gangue with similar appearan... https://ofuuacbe96n6b.timeblog.net/70682911/the-rattles-from-tell-el-farcha