An automated classification technique for large size stellar surveys is proposed. It uses the extended Kalman filter as a feature selector and pre-classifier of
The 13.7-m millimeter-wave radio telescope of Purple Mountain Observatory operates at 3200-m above the sea level near Delingha,Qinghai Province,China.Equipped w
We present disk thicknesses, some other parameters and their statistics of 108 non-edge-on spiral galaxies. The method for determining the disk thickness is bas