A method and a structure for reworking an antireflective coating layer over a semiconductor substrate. This material can be inserted into a living body, using a hollow tubular member, as desired. The mat comprises a non-woven web bonded together with a resinous binder. Workload is distributed across the plurality of engines in a load sensitive mode. A rotational member is coupled to the rotary shaft and has a power transmitting mechanism for transmitting power between the rotational unit and an external device. After the filter strength of the obtained linear prediction coefficient is adjusted, filtering may be performed in the frequency direction on the signal by using the adjusted coefficient, whereby the temporal envelope of the signal is shaped.