Abstract: An alarm control method allowing easy localization of a failure in an optical communications network is disclosed. An optical signal from a signal transmitter is monitored to produce an alarm information signal indicating whether the optical signal is normally inputted. The optical signal and an optical control signal including the alarm information signal is multiplexed and transmitted to an optical receiver through an optical transmission line. When receiving the optical control signal and the optical signal from the optical transmitter, the optical receiver determines whether the optical signal is normally received. When not normally received, transmission of a receiver-side alarm signal to a management system is controlled depending on whether the alarm information signal indicates that the optical signal has been normally inputted at the optical transmitter.

Abstract: A wavelength division multiplexed optical signal transmission method, a wavelength division multiplexed optical signal transmission system and an optical repeater enabling the number of wavelengths to be detected without error even when optical noise is caused in the optical repeater and such functions as adjustment and monitoring of the level of a wavelength division multiplexed optical signal to be performed properly. An optical repeater processes controlled optical signals of different wavelengths individually based on a control optical signal that contains wavelength number information indicating the total number of wavelengths and the presence or absence of a controlled optical signal with respect to each wavelength. Thus, even when optical noise is caused in the optical repeater, the number of wavelengths can be detected without error and such functions as adjustment and monitoring of the level of a wavelength division multiplexed optical signal can be performed properly.

Abstract: An alarm control method allowing easy localization of a failure in an optical communications network is disclosed. An optical signal from a signal transmitter is monitored to produce an alarm information signal indicating whether the optical signal is normally inputted. The optical signal and an optical control signal including the alarm information signal is multiplexed and transmitted to an optical receiver through an optical transmission line. When receiving the optical control signal and the optical signal from the optical transmitter, the optical receiver determines whether the optical signal is normally received. When not normally received, transmission of a receiver-side alarm signal to a management system is controlled depending on whether the alarm information signal indicates that the optical signal has been normally inputted at the optical transmitter.

Abstract: A process and apparatus for treating or handling scrap anodes are disclosed, which process comprises the steps of transporting scrap anodes suspended vertically from a pair of rails with their shoulder portions mounted on said rails by means of pushing projections mounted on a chain conveyer at intervals and in a downwardly protruding manner, said rails being provided under said chain conveyer; thrusting up the lower ends of the scrap anodes by means of a rotating plate during this transportation so that said scrap anodes may take a nearly horizontal position, said rotating plate being disposed under the rails and adapted for rotating vertically; thereafter moving said scrap anodes onto a supporting means provided adjacent to the rails and adapted to move horizontally by a working cylinder; hereupon stopping the scrap anodes and separating said supporting means from the scrap anodes thereby allowing them to drop down while maintaining their nearly horizontal position; receiving them on a receiving stand; turn

Abstract: A method and apparatus for grouping metal ingots of predetermined shape into ingot groups each consisting of four ingots and stacking these ingot groups in tiers to form a stack. In the method and apparatus, two kinds of ingot groups of different patterns are automatically alternately stacked in tiers utilizing the movement of a conveyor conveying the ingots, so that dangerous relative sliding movement of the ingots in the stack may not occur during transportation.