It is difficult to measure the process parameters online in the bauxite froth flotation process because the slurry deposits quickly. Especially, frequent change of the characteristics of the ore makes the process parameters change from time to time. So that, the static soft sensing models, such as the neural network model, which was obtained by a fixed set of training samples, may not track the dynamic characteristics of the process caused by change of the ore resource. And, thus, model mismatch problem occ...