Abstract: Since safe utilization of an optical transmission system is impaired if a system is adopted in which a wavelength band is divided into sub-bands and a different user is allocated to each sub-band, the optical signal monitoring device of the present invention includes: an optical signal information generating means for monitoring wavelength multiplexed signal light comprising sub-band optical signals belonging to each of a plurality of sub-bands classified by means of identification information, and generating wavelength multiplexed signal information including optical power information of each wavelength in the wavelength multiplexed signal light; a sub-band signal information generating means for generating sub-band signal information associated with the identification information, for each of the plurality of sub-bands, on the basis of the wavelength multiplexed signal information; and a sub-band signal information control means for controlling the utilization of the sub-band signal information, on the basi

Abstract: A system disconnection detection circuit for a distributed location power source having a generating element and an invertor for converting a generated output from the generating element into an AC output superimposes a selected signal on the AC output of the invertor. The circuit detects system disconnection on the output side of the invertor on the basis of the AC output of the invertor on which the selected signal has been superimposed.

Abstract: This invention relates to a process for manufacturing a shaped active carbon by using a one step phenol-formaldehyde resin, a modified phenol-formaldehyde resin or a mixture thereof as a binder. By this method, a shaped active carbon can be obtained having increased mechanical strength without deterioration of the adsorption capacity.