Abstract: Under a transient condition, a control variable is detected at each sampling interval, and operation on a controlled system is effected in a binary switching mode at each sampling interval. Parameters of a model for the controlled system are estimated on the basis of past controlled and manipulated variables, and a controlled variable sequence that can be predicted in response to application of a controlled variable over several future steps to the model is estimated, so that the system is controlled in order to render the controlled variable optimum. Under a normal operating condition, parameters are computed from the model for the control system that is obtained upon control under the transient condition, and the system is controlled by continuous manipulated-variable sampling control.