Abstract: A transmission system of embodiments is a transmission system including a plurality of transmission stations connected together via a single transmission path. Each transmission station includes a sending controller, an obtaining unit, and a first storage. The obtaining unit is configured to obtain first information regarding sending or reception of a communication frame in synchronization with sending or reception of the communication frame. The first storage is configured to store the first information and second information indicating the date and time of obtaining the first information.

Abstract: A transmission system of embodiments is a transmission system including a plurality of transmission stations connected together via a single transmission path. Each transmission station includes a sending controller, an obtaining unit, and a first storage. The obtaining unit is configured to obtain first information regarding sending or reception of a communication frame in synchronization with sending or reception of the communication frame. The first storage is configured to store the first information and second information indicating the date and time of obtaining the first information.

Abstract: First and second stations have first and second memory elements (2, 3) for storing first and second shared data, respectively, and a data transfer system (DT1) includes third and fourth memory elements (CM 12, CM 14) for storing third and fourth shared data, respectively, first and second transfer period determiner (CNT 90, CNT 92), a first transfer element (26a) working to operate in accordance with the first transfer period to have the second shared data stored in the fourth memory element (CM 14) and operate in accordance with the second transfer period to have the first shared data stored in the third memory element (CM 12), a second transfer element (26b) working for transfer of shared data between the fourth memory element (CM 14) and the third memory element (CM 12), and a third transfer element (26c) working to operate in accordance with the second transfer period to have the fourth shared data stored in the second memory element (3) and operate in accordance with the first transfer period to have the

Abstract: It is possible to leave records with which analysis of a cause can be efficiently performed when a trouble occurs in an observation target system and realize reduction in the size of the records at the time of recording. The present invention is proposed as a log recording apparatus. This log recording apparatus is provided with: a cell number storage unit to store a cell number table with cell numbers, each being data for identifying a cell number from a state/event combination; a cell number generation unit acquiring data indicating an event and a state from an observation target system, to determine a cell number corresponding to the event and the state with the use of the cell number table stored in the cell number table storage unit and the data indicating the event and the state; a log data generation unit to generate log data which includes the cell number determined by the cell number generation unit; and a log data recording unit to record the log data generated by the log data generation unit.

Abstract: First and second stations have first and second memory elements (2, 3) for storing first and second shared data, respectively, and a data transfer system (DT1) includes third and fourth memory elements (CM 12, CM 14) for storing third and fourth shared data, respectively, first and second transfer period determiner (CNT 90, CNT 92), a first transfer element (26a) working to operate in accordance with the first transfer period to have the second shared data stored in the fourth memory element (CM 14) and operate in accordance with the second transfer period to have the first shared data stored in the third memory element (CM 12), a second transfer element (26b) working for transfer of shared data between the fourth memory element (CM 14) and the third memory element (CM 12), and a third transfer element (26c) working to operate in accordance with the second transfer period to have the fourth shared data stored in the second memory element (3) and operate in accordance with the first transfer period to have the

Abstract: An object is to provide a redundant supervisory control system and a redundancy switching method thereof. In the redundant supervisory control system, remote I/O apparatuses are less likely to be inaccessible, even in a case where failures occur in plural locations. Thus, the reliability of the system is enhanced. The redundant supervisory control system including a plurality of first loop interface units in each of a pair of controllers, second loop interface units, and communication cables each connecting the plurality of first and second loop interface units with one another in a circular loop. The redundant supervisory control system is configured by connecting the controllers and the remote I/O units to one another in a plurality of loop networks. In a case where abnormality in the loop networks is detected by use of received data in the networks, the first and second loop interface units that can perform normal reception are automatically selected.

Abstract: It is possible to leave records with which analysis of a cause can be efficiently performed when a trouble occurs in an observation target system and realize reduction in the size of the records at the time of recording. The present invention is proposed as a log recording apparatus. This log recording apparatus is provided with: a cell number storage unit to store a cell number table with cell numbers, each being data for identifying a cell number from a state/event combination; a cell number generation unit acquiring data indicating an event and a state from an observation target system, to determine a cell number corresponding to the event and the state with the use of the cell number table stored in the cell number table storage unit and the data indicating the event and the state; a log data generation unit to generate log data which includes the cell number determined by the cell number generation unit; and a log data recording unit to record the log data generated by the log data generation unit.

Abstract: An object is to provide a redundant supervisory control system and a redundancy switching method thereof. In the redundant supervisory control system, remote I/O apparatuses are less likely to be inaccessible, even in a case where failures occur in plural locations. Thus, the reliability of the system is enhanced. The redundant supervisory control system including a plurality of first loop interface units in each of a pair of controllers, second loop interface units, and communication cables each connecting the plurality of first and second loop interface units with one another in a circular loop. The redundant supervisory control system is configured by connecting the controllers and the remote I/O units to one another in a plurality of loop networks. In a case where abnormality in the loop networks is detected by use of received data in the networks, the first and second loop interface units that can perform normal reception are automatically selected.