An input estimator is based on a combined MFDQ-DF and trellis for use in, for example, an ADSL environment. In the former part of the dialysis operation, the water removal is controlled so that the circulating blood volume in the body approach to the standard blood volume with the use of said target control line. The subscriber transmission equipment is provided with a switching equipment interface unit, a control path unit, and an ISDN subscriber interface unit. When a natural frequency of a magnetic head slider used to record to the magnetic disk is f and the magnetic disk rotation speed is R0, the central angle is set so as not to coincide with an angle \u03b80 expressed by \u03b80=360 \xd7. A processor is operative with each receiver and determines clock timing relationships for the clocks based on one of at least propagation or processing delays in the receivers to synchronize receiver performance. Accordingly, a deviation between a d-q axis serving as a true magnetic axis and a \u03b3-\u03b4 axis serving as a control axis is eliminated.