Abstract: A fault recovery process of a computer is provided for removing a fault from the system as soon as possible, minimizing the secondary fault and improving the availability of the system. In a reliable computer, which includes a system bus, a main memory connected to the system bus, and at least one processing board connected to the system bus, at least one processing board executes the same instructions by n (n>=3) processing units having cache memories respectively. When one of the processing units of the processing board becomes faulty, the other processing units continue executing the processes, which are being executed by the faulty processing board, and then, the processes to be registered in the faulty processing board, are succeeded by other processing boards.

Abstract: This invention provides a majority circuit, connecting a plurality of processing units. The majority circuit can detect a single error or multiple errors, and sets the majority output signal to an ineffective level when multiple errors are detected. The majority circuit includes comparators, each comparing two outputs of three processing units, and the error detector recognizes the error status and outputs the single error signal and the multiple error signal accordingly. The majority circuit also includes a selector, which selects the output of a normal processing unit, when the normal processing unit can be specified based on the comparison result. The selector changes the output to a predetermined level, when the normal processing unit cannot be specified.

Abstract: An apparatus for manufacturing cigarette dual filter plugs according to this invention comprises a first grooved convey drum for receiving a filter rod of a first type from a first hopper and conveying the filter rod, a cutting wheel for cutting the filter rod into halves during conveyence thereof by the first convey drum, and a separation guide for separating the cut rod halves so as to leave a predetermined space therebetween. The apparatus also includes a second grooved convey drum for receiving the rod halves from the first convey drum and a filter rod of a second type from a second hopper between two rod halves, and a plurality or cutting wheels are arranged near the second convey drum to cut the two rod halves and the filter rod of the second type into equal numbers of chips, to form two groups of filter chips of the first type and one group of filter chips of the second type.