Surveillance system and method

Abstract

To ensure that trend data for monitoring data can always be referenced without missing.SOLUTION: Each of two servers that constitutes a main system and a sub-system of a monitoring system has a data processing unit that calculates monitoring data for the target based on data acquired from the monitoring target, a temporary data storage unit that stores the data or the monitoring data, a monitoring data storage unit that stores monitoring data, and a synchronization processing unit that synchronizes the monitoring data with the other server. A display processing unit of the monitoring system displays information on a display based on read data read from the monitoring data storage unit or temporary data storage unit, and switches over the read destination of read data on the basis of the result of comparing the storage cycle of the monitoring data in the monitoring data storage unit with the difference time between the synchronization time when the monitoring data was last synchronized by the synchronization process before the switchover between the main system and the sub-system, and the storage time when the monitoring data was stored in the monitoring data storage unit for the first time after the switchover.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a monitoring system and a monitoring method.

Background Art

[0007] To solve the above problems, one aspect of the present invention provides a monitoring system for monitoring an object, comprising two servers constituting a primary system and a secondary system, and a display processing unit, wherein each server has a data processing unit that calculates monitoring data for the object based on data acquired from the object, a temporary data storage unit that stores the data or the monitoring data as temporary data, a monitoring data storage unit that stores the monitoring data, and a synchronization processing unit that performs synchronization processing of the monitoring data stored in each of the monitoring data storage units with the other server, wherein the display processing unit displays information on a display device based on read data read from the monitoring data storage unit or the temporary data storage unit, and switches the read destination of the read data based on the result of comparing the difference time between the synchronization time when the monitoring data was last synchronized by the synchronization processing before the primary system and secondary system of the two servers were switched and the storage time when the monitoring data was first stored in the monitoring data storage unit after the primary system and secondary system of the two servers were switched and the storage cycle in which the monitoring data is stored in the monitoring data storage unit. [Effects of the Invention]

[0008] According to the present invention, for example, an operator can always refer to trend data of monitoring data without any loss. [Brief explanation of the drawing]

[0009] [Figure 1] This figure shows an example configuration of the monitoring system in Embodiment 1 of the present invention. [Figure 2] This figure shows an example of the configuration of monitoring data in Embodiment 1 of the present invention. [Figure 3] This is a flowchart of the synchronization process between servers after the monitoring system has been started, according to Embodiment 1 of the present invention. [Figure 4] This is a flowchart of the temporary data interpolation process in Embodiment 1 of the present invention. [Figure 5] This is a flowchart illustrating the display processing of monitoring data in Embodiment 2 of the present invention. [Figure 6] This figure shows an example of the display screen of a display device based on monitoring data with missing data in Embodiment 2 of the present invention. [Figure 7] This figure shows an example of a display screen of a display device in which missing monitoring data is supplemented on the display in Embodiment 2 of the present invention. [Figure 8] This figure shows an example configuration of the monitoring system in Embodiment 3 of the present invention. [Figure 9] This hardware diagram shows an example of a computer configuration that implements a server and client terminal. [Modes for carrying out the invention]

[0010] The present invention will be described in detail below with reference to specific embodiments. In the drawings used in the following description, the same reference numerals (numbers) are used for common equipment and processing operations, and descriptions of equipment and operations (processes) that have already been described may be omitted.

[0011] Furthermore, in the following explanation, in order to distinguish between raw data such as detection data detected by various sensors on the plant side and processed data for display on a display device for monitoring purposes, raw data will generally be referred to as "data," and data stored (saved) in a database or file for monitoring and control purposes will be referred to as "monitoring data."

[0012] Monitoring data is obtained by processing detection data from various sensors installed on the plant side, but it is data acquired from the plant side (raw data) that has been calculated and processed into data suitable for monitoring. For example, monitoring data includes historical data such as alarm history and reports stored in a database, and bit data for displaying trends in detection data such as water level and flow rate stored in a file.

[0013] Furthermore, in the following explanation, a server device that performs calculations for monitoring data for plant monitoring, stores the calculated monitoring data as a database or file, displays it for monitoring purposes, and performs online operations such as controlling the plant will be referred to as the "main unit" (or "main system"), while a server device that performs standby operations to prevent system interruptions due to main unit failure, etc., will be referred to as the "slave unit" (or "slave system"). [Examples]

[0014] (Explanation of the entire system) First, the overall system S in Embodiment 1 of the present invention will be described using Figure 1. The overall system S consists of server devices 1 and 2. These server devices 1 and 2 have an operational system and a standby system relationship, such that when one server device is online (operating as the main unit), the other server device operates in standby mode (operating as a slave unit). If one server device that is operating online becomes abnormal, the other server device that is operating in standby mode takes over the operation as the main unit from the server device that is deemed abnormal and transitions to processing that performs online operations such as monitoring and control operations. In other words, the other server device performs a switchover from slave to main unit. General-purpose computers can be used for these server devices 1 and 2.

[0015] (Description of the internal configuration and functions of the server device) Next, the internal configurations of the server devices 1 and 2 and the functions of each constituent device will be described. The server device 1 and the server device 2 have the same configuration. Therefore, the configuration of the server device 1 will be described here.

[0016] In FIG. 1, the data processing unit 12 of the server device 1 captures data input from the plant 40, which is an example of a system to be monitored and controlled, via the interface unit 30 by the communication unit 11. Based on the captured data, the data processing unit 12 performs arithmetic processing on the monitoring data for monitoring and controlling the plant 40 and stores it in the database 13 and the file 14. For example, the database 13 stores history data such as alarm history and forms as monitoring data. Also, the file 14 stores bit data for displaying the trends of detection data such as water level and flow rate as monitoring data. The database 13 and the file 14 are stored in the "storage unit".

[0017] Further, the data processing unit 12 stores (stores) the captured data or the monitoring data arithmetic-processed based on the data in the temporary data storage unit 16 as "temporary data". This temporary data holds the temporary data during the period until the operation switches to the host in the server device operating as a slave device, and is used for data supplementation during the switching.

[0018] The input / output processing unit 15 has a function of retrieving necessary monitoring data from the monitoring data stored in the database 13 and the file 14 using display software and displaying the monitoring data on the display device 20. The operator can refer to the content displayed on this display device 20 and monitor the plant 40.

[0019] The operator selects what kind of monitoring data to display on the display device 20 by operating the input device 21. The input device 21 can be, for example, a keyboard. The display device 20 and the input device 21 may also be a touch panel type display device that integrates the display function of the display device 20 and the operation content input function of the input device 21. Although Figure 1 shows an example in which the display device 20 and the input device 21 are provided on server devices 1 and 2 respectively, it is also possible to provide one set of display device 20 and input device 21 and connect them to each server device 1 and 2.

[0020] The communication unit 17 is provided for the server device 1 equipped with this communication unit 17 to exchange information and data with other server devices 2. The exchange of data and information (including various commands) between the main unit and the slave unit, as described later, is carried out via the communication unit 17 of each server device.

[0021] The control unit 18 performs automatic control of the plant 40 that is being monitored. For example, when controlling the amount of water flowing through the pipelines of a water supply plant 40 using pumps, etc., when a target water volume setting value is provided to the control unit 18 via the input device 21, the control unit 18 controls the pumps, etc. within the plant 40 to eliminate the difference between this water volume setting value and the input data (water volume detection signal from the sensor).

[0022] The synchronization processing unit 19 works in conjunction with the synchronization processing unit 19 of the other server device (server device 2 in relation to server device 1, or server device 1 in relation to server device 2) to synchronize the monitoring data stored in the databases 13 and files 14 of the primary server device and the secondary server device at a predetermined synchronization cycle. The transmission and reception of monitoring data between the primary and secondary server devices is performed via the communication unit 17.

[0023] The operator can decide which of the two server devices 1 and 2 will be operated as the main unit by operating the input device 21. After the main and slave units have been set in server devices 1 and 2, in this embodiment, the standby server device diagnoses the status of the main unit (the server device that is online and running). If the main unit is diagnosed as not functioning correctly, in other words, as being abnormal, the server device that was operating as the main unit will either terminate its operation or become a slave unit, and the server device that was operating as a slave unit will switch over and operate as the main unit.

[0024] Figure 2 shows an example of the configuration of monitoring data. In the example in Figure 2, the monitoring data is time-series data in seconds. The monitoring data stored in the main unit's memory is periodically transferred to the slave unit in fixed batches. The slave unit synchronizes the monitoring data between the main unit and the slave unit by writing the monitoring data received from the main unit to its own memory unit. When synchronization is complete, the slave unit transfers the time t1 of synchronization completion to the main unit, and the main unit records time t1 in its own monitoring data. Time t1 is the time when the monitoring data was last synchronized by the synchronization process before the main and slave systems of the two server devices 1 and 2 were switched over.

[0025] Furthermore, after the primary and secondary systems switch, the new primary system, which had been operating as a secondary system, stores the monitoring data in its own monitoring data storage unit, and the time t2 at which the storage of the monitoring data began is recorded in the monitoring data. Time t2 is the time when the monitoring data was first stored in the monitoring data storage unit of the server device that became the primary system after the primary and secondary systems of the two servers switched. The storage cycle of the monitoring data is compared with the difference in time between time t2 and time t1 (t2-t1), and based on this comparison result, it is determined whether the storage cycle of the monitoring data in the monitoring data storage unit has been reached between the data synchronization time (time t1) and the startup time of the new primary system (time t2), and a flag X indicating whether or not monitoring data supplementation processing is necessary is recorded according to the determination result.

[0026] Flag X is set to "1" if interpolation processing is required, and to "0" if interpolation processing is not required. If the difference time (t2-t1) is greater than the storage cycle of the monitoring data, interpolation processing of the monitoring data is required. If the difference time (t2-t1) is less than or equal to the storage cycle of the monitoring data, the new main unit will store the data for the next storage cycle, so interpolation processing of the monitoring data is not required.

[0027] (Synchronization process between the main and slave server devices) Figure 3 shows the synchronization process flow between server devices 1 and 2. The synchronization process of monitoring data between the main and slave server devices, as shown in the flowchart of Figure 3, is performed periodically by the monitoring system S. The synchronization process of monitoring data between the main and slave server devices starts with one server device 1 or 2 acting as the main device and the other as the slave device, and continues thereafter until the monitoring system S stops.

[0028] When the monitoring system S is activated, in step S101, data acquired from plant 40 and monitoring data based on this data are stored in the main unit's memory. Next, in step S102, the main unit determines whether or not the transfer timing in the synchronization cycle of the monitoring data stored in the memory has arrived. If it is the transfer timing (step S102 YES), the main unit moves to step S103, and if it is not the transfer timing (step S102 NO), it returns to step S101.

[0029] In step S103, the main unit transfers monitoring data from the main unit to the slave unit. The slave unit stores the monitoring data received from the main unit in its own memory. In this way, the monitoring data is synchronized between the main unit and the slave unit.

[0030] Next, in step S104, the slave unit confirms that the monitoring data synchronized with the main unit has been stored in the slave unit's memory (that the synchronization of monitoring data with the main unit is complete) by opening the file and analyzing its contents. Next, in step S105, the slave unit transmits the time t1 at which the synchronization of monitoring data was completed to the main unit. Next, in step S106, the main unit records the time t1 received from the slave unit in the monitoring data stored in the main unit's memory.

[0031] (Supplementing monitoring data using temporary data during server switching) Figure 4 is a flowchart illustrating the process of supplementing monitoring data using temporary data when data loss occurs during server switching. The process of supplementing monitoring data using temporary data, as shown in the flowchart of Figure 4, is executed when the monitoring system S determines that a server switch should be performed. Server switching is performed when a malfunction occurs in the main unit and it becomes impossible for it to continue operating as the main unit, so that the main unit and the slave unit are swapped and the monitoring system S can continue to operate. Hereinafter, the swapped main unit and slave unit will be referred to as the "new main unit" and the "new slave unit," respectively.

[0032] First, in step S201, the main and slave units of the monitoring system S execute server switching processing in response to a server switching command to swap the main and slave units. Next, in step S202, after the server switching processing is completed, the new main unit, which has transitioned from standby operation to online operation, records the time t2 when the switchover was completed in the new main unit's monitoring data.

[0033] Next, in step S203, the new main unit calculates the difference in time (t2-t1) between time t2 and time t1 and compares it with the storage cycle of the main unit's monitoring data. If the difference in time (t2-t1) between time t2 and time t1 is greater than the storage cycle of the monitoring data (step S203YES), the new main unit moves to step S204. If the difference in time (t2-t1) is less than or equal to the storage cycle of the monitoring data (step S203NO), the new main unit terminates the data interpolation process using temporary data in order to store the data for the next storage cycle.

[0034] In step S204, the new main unit determines in step S203 that there is missing data in the synchronization of monitoring data and that completion processing is necessary, so it sets the data flag X of the monitoring data stored in the new main unit's memory to 1. Next, in step S205, the new main unit performs data completion processing by extracting data corresponding to the range from time t1 to time t2 from the new main unit's temporary data storage unit 16 and writing it to the monitoring data for which flag X was set to 1 in step S204. Next, in step S206, the new main unit initializes the flag X=1 of the monitoring data for which data completion processing was performed in step S205 (setting X=0). When step S206 is completed, the monitoring system S finishes the monitoring data completion processing using temporary data.

[0035] In Example 1, the process shown in Figures 3 and 4 allows for the rapid identification of data loss locations and data completion processes when data loss occurs in monitoring data during server switching. This is achieved by managing the need for data completion and the data loss interval using flags and timestamps. [Examples]

[0036] In Example 1, when there is data loss in the monitoring data after the switchover, an example was described in which temporary data is used to supplement the monitoring data. In contrast, in Example 2, in addition to the above, when there is data loss in the monitoring data after the switchover and the supplementation process is not yet completed, the data recorded in the temporary data storage unit 16 is combined with the monitoring data on the display and displayed on the display device 20 to prevent data loss on the display.

[0037] (Display processing of monitoring data in Example 2) Figure 5 is a flowchart illustrating the display process for monitoring data in Example 2. The display process for monitoring data shown in the flowchart of Figure 5 is executed when the display software, which operates in the input / display processing unit 15 of the server devices 1 and 2 of the monitoring system S, decides to display the monitoring data on the display device 20. The display software is a function for displaying monitoring data on the display device 20, which is realized by being executed by the processors of the server devices 1 and 2. The terms "main machine" and "slave machine" used in the context of the display process for monitoring data refer to the main machine and slave machine at the time the display process is executed. The term "own machine" used in the context of the display process for monitoring data refers to the server devices 1 and 2 that execute the display process for monitoring data.

[0038] First, in step S301, the display software opens the monitoring data for the main unit. Next, in step S302, the display software refers to flag X of the monitoring data opened in step S301 to check whether data completion processing is required. If data completion processing is required (X=1) (step S302YES), the display software moves to step S303, and if data completion processing is not required (X=0) (step S302NO), it moves to step S304.

[0039] In step S303, the display software combines the data from the monitoring data opened in step S301, excluding the data corresponding to time t1 to time t2, with the temporary data stored in the main unit's temporary data storage unit 16 corresponding to time t1 to time t2, and outputs it to the display device 20. While the data combined in step S303 is being displayed by the display software, the synchronization processing unit 19 performs data completion processing on the monitoring data (step S205 in Figure 4) and completes the data completion processing. This prioritizes displaying the data without data loss before the completion of the data completion processing, and by performing the data completion processing in the background of the display, it is possible to enhance convenience without making the operator aware of data loss.

[0040] On the other hand, in step S304, the display software outputs all of the monitoring data opened in step S301 directly to the display device 20. In this way, the display software switches the data read from to the display device 20 depending on whether or not interpolation processing is necessary.

[0041] As shown in Figure 5, the monitoring data interpolation process allows for the display of data when there are gaps in the monitoring data after a server switchover, but the interpolation process for the missing data is not yet complete. In such cases, the monitoring data from the main unit and the temporary storage data from the main unit corresponding to the missing portion are combined and displayed on the screen. On the other hand, if the interpolation process for missing data in the monitoring data after a server switchover is complete, the monitoring data from the main unit is displayed on the screen. This ensures that data loss on the display device 20 is never caused. Furthermore, since the temporary storage data is data within the device used for the interpolation process of monitoring data, data consistency can be maintained by using the same data to interpolate data loss on the display.

[0042] The data interpolation process shown in Figure 5 may be repeated at regular intervals. Since data loss in the monitoring data may be compensated for in the memory after a certain period of time, displaying the compensated monitoring data after the completion of the interpolation process, rather than displaying the data interpolation on the display, will result in a normal data display.

[0043] (Example of display screen 20D of display device 20 based on monitoring data) Figure 6 shows an example of the display screen 20D of the display device 20 based on monitoring data with missing data in Embodiment 2 of the present invention. Figure 7 shows an example of the display screen 20D of the display device 20 in which the missing monitoring data in Embodiment 2 of the present invention has been supplemented on the display.

[0044] As shown in Figures 6 and 7, the display screen 20D represents time on the horizontal axis and the value of the monitoring data on the vertical axis. The display screen 20D includes a screen operation unit 20D1 that accepts inputs for the monitoring data to be displayed, such as the plant from which the data is output, the type of monitoring data, the date, the display unit of the monitoring data, and the display time of the table monitoring data. The display unit of the monitoring data is, for example, the time unit of the monitoring data to be displayed at once in the display area 20D2 of the monitoring data, such as an hourly unit, a daily unit, a weekly unit, etc.

[0045] In the example shown in Figure 6, there is missing data 20D3 that occurred when the main and slave units of server devices 1 and 2 were switched over. As a result, the graph of monitoring data displayed in the display area 20D2 loses continuity in the area of ​​missing data 20D3. Therefore, the operator of the monitoring system S cannot know the behavior of the monitoring data in the area of ​​missing data 20D3 until the interpolation process is completed.

[0046] However, in this embodiment, as shown in Figure 7, before the completion of the missing data imputation process, the monitoring data and temporary data are combined, and the missing data 20D3 is imputed on the display of the display device 20 using the temporary data to display a graph. This allows the operator of the monitoring system S to immediately know the behavior of the monitoring data in the portion with missing data 20D3, and to appropriately control the equipment of the plant being monitored.

[0047] Furthermore, when the graph display of monitoring data in display area 20D2 is updated at regular intervals, if there is missing data in the monitoring data and the data completion process has not been completed, the monitoring data and temporary data are combined, and the missing data 20D3 is completed on the display of the display device 20 using the temporary data to quickly display the graph. On the other hand, when the graph display of monitoring data in display area 20D2 is updated at regular intervals, if the data completion process for missing data in the monitoring data is completed, the graph is displayed using the completed monitoring data.

[0048] In Example 2, in a monitoring system that monitors a target, the destination of the read data is switched based on the difference between the synchronization time when the monitoring data was last synchronized by a synchronization process before the primary and secondary systems of the two servers were switched, and the storage time when the monitoring data was first stored in the monitoring data storage unit after the primary and secondary systems of the two servers were switched (i.e., the content of flag X). This prevents data loss on the display device 20 when there is a gap in the monitoring data after the server switch, but the processing to fill in the missing data has not been completed.

[0049] Furthermore, the method for avoiding data loss in the display of monitoring data is not limited to combining the data within the range of data loss recorded in the temporary data storage unit 16 with the monitoring data and displaying it on the display device 20. For example, a graph of the entire range of the display target may be created based on the data recorded in the temporary data storage unit 16 and displayed on the display device 20, and after the completion of the data completion process for missing data, the graph may be displayed based on the completed monitoring data. [Examples]

[0050] In Example 2, the process of combining monitoring data and temporary data read from the temporary data storage unit 16 using display software and outputting it to the display device 20 was performed by display software operating in the input / display processing unit 15 of server devices 1 and 2. However, this is not the only option; as shown in Figure 8, the process of combining monitoring data and temporary data read from the temporary data storage unit 16 using display software and outputting it to the display device 20 may also be performed by display software operating in the input / display processing unit 15 of client terminal 3 other than the main unit and slave unit. The display software operating in the input / display processing unit 15 of client terminal 3 can access the database 13 and file 14 of the main unit and the temporary data storage unit 16 of the slave unit, and if there is a gap in the monitoring data, it can combine the monitoring data and the temporary data read from the temporary data storage unit 16 using display software and output it to the display device 20 connected to client terminal 3.

[0051] According to Example 3, even when accessing monitoring data from a client terminal, missing data can be supplemented and displayed on the screen, similar to Example 2.

[0052] (Computer 1000 hardware) Figure 9 is a hardware diagram showing an example configuration of a computer 1000 that implements server devices 1 and 2 and a client terminal 3.

[0053] Computer 1000 is a computer comprising a CPU and other processors 1001, a main memory 1002, an auxiliary memory 1003, a network interface 1004, an input device 1005, and an output device 1006, all interconnected via an internal communication line 1009 such as a bus.

[0054] The processor 1001 controls the overall operation of the computer 1000. The main memory 1002 is composed of, for example, volatile semiconductor memory and is used as the work memory of the processor 1001. The auxiliary storage device 1003 is composed of a large-capacity non-volatile storage device such as a hard disk drive, SSD (Solid State Drive), or flash memory, and is used to retain various programs and data for long periods of time.

[0055] The executable program 1100 stored in the auxiliary storage device 1003 is loaded into the main memory device 1002 when the computer 1000 starts up or when needed, and executed by the processor 1001. In this way, the various functional units of the server devices 1 and 2 and the client terminal 3 that perform various processes are realized.

[0056] The executable program 1100 may be recorded on a non-temporary recording medium, read from the non-temporary recording medium by a media reader, and loaded into the main memory 1002. Alternatively, the executable program 1100 may be obtained from an external computer via a network and loaded into the main memory 1002.

[0057] The network interface 1004 is an interface device for connecting computer 1000 to various networks within the system or for communicating with other computers. The network interface 1004 consists of, for example, a NIC (Network Interface Card) such as a wired LAN (Local Area Network) or a wireless LAN.

[0058] The input device 1005 consists of a keyboard, a mouse, a pointing device such as a touch sensor, and is used by the operator to input various instructions and information to the computer 1000. The output device 1006 consists of a display device such as a liquid crystal display or an organic EL (Electro Luminescence) display, or an audio output device such as a speaker, and is used to present necessary information to the operator when needed.

[0059] It should be noted that the present invention is not limited to the embodiments described above, and includes various modifications. For example, the embodiments described above are explained in detail to make the present invention easier to understand, and are not necessarily limited to those having all the configurations described. Furthermore, it is possible to replace or combine parts of the configuration of one embodiment with the configuration of another embodiment, and it is also possible to add the configuration of another embodiment to the configuration of one embodiment. In addition, it is possible to add, delete, replace, integrate, or distribute parts of the configuration of each embodiment with other configurations. Furthermore, each process shown in the embodiments may be distributed or integrated as appropriate based on processing efficiency or implementation efficiency. [Explanation of symbols]

[0060] 1,2…Server device, 3…Client terminal, 11,17…Communication unit, 12…Data processing unit, 13…Database, 14…File, 15…Input / Display processing unit, 16…Temporary data storage unit, 18…Control unit, 19…Synchronization processing unit, 20…Display device, 21…Input device, 30…Interface unit, 40…Plant

Claims

1. A surveillance system for monitoring an object, comprising: Two servers that make up a primary and secondary system; a display processing unit, Each of the servers a data processing unit that calculates monitoring data for the target based on data acquired from the target; a temporary data storage unit that stores the data or the monitoring data as temporary data; a monitoring data storage unit for storing the monitoring data; a synchronization processing unit that performs a synchronization process of the monitoring data stored in each of the monitoring data storage units with the other server, The display processing unit displaying information on a display device based on the read data read from the monitoring data storage unit or the temporary data storage unit; The read destination of the read data is switched based on a result of comparing the difference between the synchronization time at which the monitoring data was last synchronized by the synchronization process before the two servers were switched between the primary and secondary systems and the storage time at which the monitoring data was first stored in the monitoring data storage unit after the two servers were switched between the primary and secondary systems with a storage period at which the monitoring data is stored in the monitoring data storage unit. A monitoring system characterized by:

2. 2. The monitoring system of claim 1, The display processing unit At regular intervals, the read destination of the read data is switched based on the result of comparing the differential time with the storage period. A monitoring system characterized by:

3. 2. The monitoring system of claim 1, The display processing unit When the difference time is longer than the storage period, the information is displayed on the display device based on the monitoring data read from the monitoring data storage unit and the temporary data read from the temporary data storage unit. A monitoring system characterized by:

4. 4. The monitoring system of claim 3, The synchronization processing unit The temporary data is used to perform a process of complementing missing data in the monitoring data at the differential time. A monitoring system characterized by:

5. 5. The monitoring system of claim 4, The display processing unit from when the two servers are switched between the primary and secondary systems until the completion of the complementation process, the monitoring data and the temporary data are combined to complement the missing data on the display device, and the information is displayed on the display device; After the completion of the complementation process, the information is displayed on the display device based on the monitoring data after the completion of the complementation process. A monitoring system characterized by:

6. 6. The monitoring system of claim 5, The synchronization processing unit The display processing unit combines the monitoring data and the temporary data to complement the missing data on the display device, and the information is displayed on the display device while the information is being displayed on the display device. A monitoring system characterized by:

7. 6. The monitoring system of claim 5, The display processing unit A period of the missing data in the monitoring data is identified based on the synchronization time and the storage time, and the monitoring data that falls outside the period is combined with the temporary data that falls within the period to complement the missing data on the display device. A monitoring system characterized by:

8. 5. The monitoring system of claim 4, The synchronization processing unit determining whether or not a process for compensating for the missing data in the monitoring data is necessary based on the synchronization time and the storage time, and recording a flag indicating whether or not the compensating process is necessary in the monitoring data; performing the complementation process when the flag indicates the necessity of the complementation process; When the completion process is completed, the flag is updated to indicate that the completion process is not required. A monitoring system characterized by:

9. 2. The monitoring system of claim 1, Each of the servers has the display processing unit. A monitoring system characterized by:

10. 2. The monitoring system of claim 1, a terminal having the display processing unit A monitoring system characterized by:

11. A monitoring method performed by a monitoring system that monitors an object, comprising: The monitoring system includes: Two servers that make up a primary and secondary system; a display processing unit; Each of the servers a data processing unit that calculates monitoring data for the target based on data acquired from the target; a temporary data storage unit that stores the data or the monitoring data as temporary data; a monitoring data storage unit for storing the monitoring data; a synchronization processing unit that performs a synchronization process of the monitoring data stored in each of the monitoring data storage units with the other server, The display processing unit displaying information on a display device based on the read data read from the monitoring data storage unit or the temporary data storage unit; The read destination of the read data is switched based on a result of comparing the difference between the synchronization time at which the monitoring data was last synchronized by the synchronization process before the two servers were switched between the primary and secondary systems and the storage time at which the monitoring data was first stored in the monitoring data storage unit after the two servers were switched between the primary and secondary systems with a storage period at which the monitoring data is stored in the monitoring data storage unit. A monitoring method comprising:

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