JP7322656B2 - Maintenance schedule creation program, maintenance schedule creation method, and maintenance schedule creation device - Google Patents

Description

The present invention relates to a maintenance schedule creation program, a maintenance schedule creation method, and a maintenance schedule creation device.

2. Description of the Related Art In plants such as factories and power plants, long-term and/or periodic maintenance work is performed on each of a plurality of facilities arranged in the plant.

"Equipment" includes, for example, machinery, equipment, piping, and the like. "Maintenance work" is, for example, maintenance management or work related to maintenance, such as inspection, cleaning, repair, replacement, and updating of facilities. Maintenance work may be referred to as "maintenance."

It is conceivable that the maintenance work manager adjusts in advance the workable schedule for each of a plurality of pieces of equipment, prepares an annual maintenance schedule, and performs the maintenance work according to the maintenance schedule.

JP 2010-282353 A JP-A-9-285948

A plant often has a large number of large and small facilities. Since maintenance work includes a plurality of works for each facility to be maintained, the total number of maintenance work for the entire plant and the number of combinations of schedules for each work are enormous.

Therefore, it is difficult for a manager to easily create an optimal (eg, minimum maintenance cost) schedule for such a plant.

In one aspect, an object of the present invention is to efficiently create a maintenance schedule in a plant in which a plurality of facilities are arranged.

In one aspect, the maintenance schedule creation program may cause a computer that creates maintenance schedules for each of a plurality of facilities to perform the following processes. The processing is based on first information defining each step of the process using the plurality of facilities, the interrelationship between the steps, and the processing capacity of each step, without stopping the facility. a first process of acquiring a first processing capacity of a process; acquiring a second processing capacity of the process when one of the plurality of facilities is stopped based on the first information ; and a second process of calculating and evaluating a maintenance cost of the maintenance schedule based on the first processing capacity and the second processing capacity. Further, in the above processing, among the maintenance work included in the maintenance schedule , for a pair of maintenance work that can be performed on overlapping schedules, both schedules are set based on second information that defines conditions for each of a plurality of maintenance work. You may create it as a constraint to overlap . Furthermore, the processing may cause the second processing to be repeatedly executed while switching validity or invalidity of each of the plurality of constraints.

In one aspect, it is possible to efficiently create a maintenance schedule in a plant in which multiple pieces of equipment are arranged.

FIG. 10 is a diagram showing a comparative example of maintenance schedule creation techniques; FIG. 10 is a diagram showing a comparative example of maintenance schedule creation techniques; It is a figure which shows the calculation example of an opportunity loss cost. FIG. 3 is a diagram showing an example of expressing a treatment process of a plant as a network diagram of products flowing between processes. 1 is a block diagram showing a hardware configuration example of a computer that implements the functions of a maintenance schedule creation device according to an embodiment; FIG. 1 is a block diagram showing a functional configuration example of a maintenance schedule creation device according to an embodiment; FIG. It is a figure which shows an example of processing process information. It is a figure which shows an example of maintenance schedule information. 4 is a flow chart showing an example of overall operation related to creation of a maintenance schedule by a creation device; FIG. 2 is a diagram visualizing treatment process information as a directed graph in which steps are connected by arrows pointing from a previous step to the next step. FIG. 8 is a diagram showing an example of a network diagram of the processing process illustrated in FIG. 7; FIG. 4 is a flow chart showing an operation example of a network diagram creating unit; FIG. 12 is a diagram showing an example of a technique for creating the network diagram shown in FIG. 11; FIG. FIG. 12 is a diagram showing an example of a technique for creating the network diagram shown in FIG. 11; FIG. 4 is a flow chart showing an example of operation by a maximum processing capacity calculation unit; FIG. 12 is a diagram showing an example of a method of calculating the maximum processing capacity based on the network diagram shown in FIG. 11; FIG. 12 is a diagram showing an example of a method of calculating the maximum processing capacity based on the network diagram shown in FIG. 11; It is a figure which shows an example of the collection process by the between-work restrictions preparation part. It is a figure which shows an example of the executability confirmation process by the between-work constraint creation part. It is a figure which shows an example of inter-work restrictions. 6 is a flowchart showing an example of maintenance schedule creation processing by a schedule creation unit; It is a figure which shows an example of a maintenance schedule creation method. It is a figure which shows an example of a maintenance schedule creation method. It is a figure which shows an example of a maintenance schedule creation method. 7 is a flowchart showing an example of maintenance cost determination processing by a maintenance cost determination unit; It is a figure which shows an example of the calculation method of daily processing capacity. FIG. 10 is a diagram showing a display example of maintenance schedule and maintenance cost creation results; It is a figure which shows the structural example of a system provided with a preparation apparatus and a terminal.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the embodiment described below is merely an example, and various modifications can be made without departing from the spirit of the embodiment. In the drawings used in the following embodiments, parts with the same reference numerals represent the same or similar parts unless otherwise specified.

[1] One Embodiment [1-1] Creation of Maintenance Schedule FIGS. 1 and 2 are diagrams showing comparative examples of maintenance schedule creation techniques. As shown in FIG. 1, in a comparative example, the manager adjusts the work schedule for each work in equipment maintenance work 100 and creates a maintenance schedule 200 . In schedule adjustment, the manager considers restrictions (conditions) regarding, for example, the work execution period (deadline), work days, equipment to be worked on, person in charge of work, equipment used for maintenance work, and the like.

As an example, as shown in FIG. 2, the manager prepares a provisional schedule based on the period determined for each facility and work, and adjusts the schedule while checking the constraint satisfaction and evaluating the cost. Then, the manager creates the maintenance schedule 200 by determining the work start date that satisfies the constraints and reduces the maintenance cost.

Restrictions include, for example, that the work must be executed within a specified execution period, that the person in charge can only execute one work at a time, and that there is an upper limit to the number of machines used, such as heavy machinery. .

Maintenance costs include, for example, work costs that do not depend on the maintenance date, such as material costs and labor costs, work costs that depend on the maintenance date, such as the residual value (book value) of parts, and opportunities determined by the combination of work cost of loss, may be included.

However, as mentioned above, when creating a maintenance schedule for a plant with many large and small facilities, the number of schedule combinations is enormous. difficult to do. For example, even if an experienced manager creates a maintenance schedule based on their experience and knowledge, the more work they do, the more difficult and time consuming it will be to create it. Identifying the schedule to minimize is difficult.

A method of automatically generating a schedule using an algorithm such as mathematical optimization is also conceivable.

(a) Since the opportunity loss cost cannot be expressed as a simple formula or function, it is difficult to appropriately calculate the opportunity loss cost.

(b) The greater the number of tasks, the wider the search range for combinations of tasks, resulting in a longer optimization processing time, and only local optimum results can be obtained.

Therefore, in one embodiment, as an example of a method of efficiently creating a maintenance schedule, a method of making it possible to create a schedule with a low maintenance cost in a short period of time will be described.

[1-2] Description of an Embodiment First, the opportunity loss cost will be described. FIG. 3 is a diagram illustrating an example of calculating the opportunity loss cost. As exemplified in FIG. 3, the opportunity loss cost simulates the production volume when one or more facilities are stopped based on the model 300 (see upper left of FIG. 3) showing the manufacturing process and production volume during normal times. can be obtained by

In the example of FIG. 3, as one or more pieces of equipment, when machine B1 is stopped (see the lower left of FIG. 3), when machine C is stopped (see the upper right of FIG. 3), and when machines B2 and C are stopped (see the lower right of FIG. 3), the respective production amounts are calculated. The opportunity loss cost can be calculated based on the (normal) production volume of the model 300, the production volume when the equipment is stopped, the equipment stoppage period, and the like. The production volume shown in FIG. 3 indicates the maximum production volume for a predetermined period (for example, one day, one hour, one minute, etc.).

As exemplified in FIG. 3, the opportunity loss cost due to equipment stoppage depends on the combination of equipment that is stopped at the same time, in addition to the treatment process and the production capacity of the equipment. In order to reduce the opportunity loss cost, it is effective to process multiple maintenance tasks that overlap in the scope of influence of equipment stoppages on overlapping schedules.

As described above, the larger the scale of the plant (the number of facilities), the greater the number of work combinations. Further, in order to calculate the opportunity loss cost, as shown in FIG. 2, the method of calculating the cost for each facility and work and taking the total sum is not sufficient, and it takes time and effort.

Therefore, the creation device according to one embodiment creates a maintenance schedule by focusing on the relationship between the treatment process of the plant and the products flowing between each process. Hereinafter, the creating device may be simply referred to as "creating device".

FIG. 4 is a diagram showing an example of expressing a treatment process of a plant as a network diagram NE of products flowing between processes. For the sake of convenience, the creation device creates a network diagram NE as an example of information indicating the relationship between the plant treatment process and the products flowing between the processes. However, the creation device is not limited to this.

In one embodiment, the network diagram NE is not essential. For example, instead of the network diagram NE, the creation device may use or create various information such as a table, DB (database), array, etc. showing the above relationships. good.

The network diagram NE is a diagram in which each "process" is arranged as a node ND between the start "s" and the end "e" of the treatment process of the plant, and the nodes ND are connected by arrows. Arrows indicate product flow between processes. In the network diagram NE shown in the upper part of FIG. 4, an example of the amount of processing that can be processed in each process is shown above the arrows.

A "process" is one treatment subdivided from a treatment process, and may also be referred to as a "procedure". A "process" may use one or more pieces of equipment. Equipment may be used redundantly between “processes”. One or more operations may be performed for each "step" in the maintenance operation.

In one embodiment, the production device may calculate the lost opportunity cost using the network diagram NE, as illustrated on the left side of FIG. In the network diagram NE shown in the middle left of FIG. 4, an example of the maximum flow rate of each process is shown above the arrows when the product flows from upstream to downstream. In the lower left part of FIG. 4, it is assumed that the maintenance work of the process C1 is performed, and the processing amount of each process when the amount of processing (quantity of products) flowing in and out of the process C1 is set to "0". Here is an example. It can be seen that the processing amount decreases from "20" to "10" from the left middle stage to the left bottom stage in FIG.

Also, in one embodiment, the production device may use the network diagram NE to generate constraints for reducing the cost of lost opportunities, as illustrated on the right side of FIG. As illustrated in the middle right part of FIG. 4, when the process C1 using the equipment "EQ04-1" is stopped, the flow rate of the product in the process D1 using the equipment "EQ05" is also "0". For this reason, the process D1 is a process that should be performed so that the schedule overlaps with that of the process C1. In other words, it is effective in reducing opportunity loss costs. By using such constraints, a good solution can be obtained in a short time in the maintenance schedule optimization calculation.

Therefore, as exemplified in the lower right part of FIG. 4, the creation device appropriately adds constraints such that the schedules of a plurality of tasks that are performed independently overlap each other. Calculations can be performed.

In this way, the creation device according to one embodiment calculates the opportunity loss cost from changes in the amount of processing when performing maintenance work, as illustrated on the left side of FIG. 4, based on the relationship shown in the network diagram NE. to calculate and evaluate the schedule.

In addition, as illustrated on the right side of FIG. 4, the creation device finds a pair of tasks that should be executed on overlapping schedules, sets them as constraints in optimization (inter-task constraints), and appropriately activates the constraints to search for solutions. The space can be restricted to regions where good solutions exist. This makes it possible to reduce the amount of calculation and improve the solution quality.

[1-3] Configuration Example of One Embodiment The creation device may be configured as an information processing device, for example, a computer such as a server or a PC (Personal Computer). The creation device may be, for example, a virtual server (VM; Virtual Machine) or a physical server. Also, the function of the creation device may be realized by one computer or may be realized by two or more computers.

The creation device may be installed in a plant, a data center, or the like, and operated as a so-called on-premise. Also, at least part of the functions of the creation device may be implemented using HW (Hardware) resources and NW (Network) resources provided in a cloud environment.

[1-3-1] Hardware Configuration Example FIG. 5 is a block diagram showing an HW configuration example of the computer 10 that implements the functions of the creation device. When a plurality of computers are used as HW resources for realizing the functions of the creation device, each computer may have the HW configuration illustrated in FIG.

As shown in FIG. 5, the computer 10 includes, as an example of HW configuration, 10f.

The processor 10a is an example of an arithmetic processing device that performs various controls and operations. The processor 10a may be communicatively connected to each block in the computer 10 via a bus 10i. Note that the processor 10a may be a multiprocessor including a plurality of processors, a multicore processor having a plurality of processor cores, or a configuration having a plurality of multicore processors.

Examples of the processor 10a include integrated circuits (ICs) such as CPUs, MPUs, GPUs, APUs, DSPs, ASICs, and FPGAs. A combination of two or more of these integrated circuits may be used as the processor 10a. CPU is an abbreviation for Central Processing Unit, and MPU is an abbreviation for Micro Processing Unit. GPU is an abbreviation for Graphics Processing Unit, and APU is an abbreviation for Accelerated Processing Unit. DSP is an abbreviation for Digital Signal Processor, ASIC is an abbreviation for Application Specific IC, and FPGA is an abbreviation for Field-Programmable Gate Array.

The memory 10b is an example of HW that stores information such as various data and programs. Examples of the memory 10b include a volatile memory such as a DRAM (Dynamic Random Access Memory).

The storage unit 10c is an example of HW that stores information such as various data and programs. Examples of the storage unit 10c include magnetic disk devices such as HDDs (Hard Disk Drives), semiconductor drive devices such as SSDs (Solid State Drives), and various storage devices such as nonvolatile memories. Examples of nonvolatile memory include flash memory, SCM (Storage Class Memory), ROM (Read Only Memory), and the like.

Further, the storage unit 10c may store a program 10g (maintenance schedule creation program) that implements all or part of various functions of the computer 10. FIG. For example, the processor 10a of the creation device can implement the function of the creation device by loading the program 10g stored in the storage unit 10c into the memory 10b and executing it.

The IF unit 10d is an example of a communication IF that controls connection and communication with a network. For example, the IF unit 10d may include an adapter conforming to LAN (Local Area Network) such as Ethernet (registered trademark), or optical communication (for example, FC (Fibre Channel)). The adapter may support one or both of wireless and wired communication methods. For example, the program 10g may be downloaded from the network to the computer 10 via the communication IF and stored in the storage section 10c.

The I/O section 10e may include one or both of an input device and an output device. Input devices include, for example, a keyboard, a mouse, and a touch panel. Examples of output devices include monitors, projectors, and printers.

The reading unit 10f is an example of a reader that reads data and program information recorded on the recording medium 10h. The reading unit 10f may include a connection terminal or device to which the recording medium 10h can be connected or inserted. Examples of the reading unit 10f include an adapter conforming to USB (Universal Serial Bus), a drive device for accessing a recording disk, and a card reader for accessing flash memory such as an SD card. The recording medium 10h may store the program 10g, or the reading unit 10f may read the program 10g from the recording medium 10h and store it in the storage unit 10c.

Examples of the recording medium 10h include non-temporary computer-readable recording media such as magnetic/optical discs and flash memories. Examples of magnetic/optical discs include flexible discs, CDs (Compact Discs), DVDs (Digital Versatile Discs), Blu-ray discs, and HVDs (Holographic Versatile Discs). Examples of flash memories include semiconductor memories such as USB memories and SD cards.

The HW configuration of the computer 10 described above is an example. Therefore, HW in the computer 10 may be increased or decreased (for example, addition or deletion of arbitrary blocks), division, integration in arbitrary combinations, addition or deletion of buses, or the like may be performed as appropriate.

[1-3-2] Functional Configuration Example Next, a functional configuration example of the maintenance schedule creation device (creation device) 1 according to one embodiment will be described with reference to FIG. A creation device 1 creates a maintenance schedule for each of a plurality of facilities. As shown in FIG. 6, the creation device 1 illustratively includes a memory unit 11, a network diagram creation unit 12, a maximum processing capacity calculation unit 13, an inter-work constraint creation unit 14, a schedule creation unit 15, and a maintenance cost determination unit. A portion 16 may be provided. At least part of the functions of blocks 12 to 16 may be written in the program 10g and implemented by the processor 10a developing the program 10g in the memory 10b and executing it.

The memory unit 11 is an example of a storage unit, and may store various information used by the creation device 1 . The memory unit 11 may be realized by, for example, a storage area included in at least one of the memory 10b, the storage unit 10c, and the recording medium 10h of the computer 10. FIG.

The memory unit 11 may store processing process information 11a and maintenance schedule information 11d shown in FIGS. At least one of the treatment process information 11a and the maintenance schedule information 11d may be existing information used for plant management, and may be acquired (input) in advance in the creation device 1 and stored in the memory unit 11. .

The treatment process information 11a is an example of first information defining each step of a process using a plurality of facilities, the interrelationship between each step, and the processing capacity of each step. For example, the treatment process information 11a is information indicating the treatment process of a plant that completes a product from an input material through several processes and the treatment capacity of each process. In one step of the treatment process, a process (flow) is performed in which an intermediate product received from a previous step is subjected to a predetermined treatment in that step and passed on to the next step. Note that the treatment process is defined for each product.

FIG. 7 is a diagram showing an example of the processing process information 11a. As shown in FIG. 7, the processing process information 11a includes, for example, a product ID (Identifier) that is an example of a product identifier, a process ID that is an example of a process identifier, a process name that is the name of the process, equipment used, and so on. , processing capacity, and next process ID. The example of FIG. 7 shows the processing process information 11a defined for the product with the product ID "ABC00123".

Equipment used is an example of an identifier for equipment used in the process. When a plurality of equipments are used in the process, identifiers of the plurality of equipments may be set for the used equipment. The processing capacity may be set to a numerical value indicating the processing capacity of the process. Between processes with the same product ID, the time unit and unit system of the processing capacity are aligned. The next process ID is an example of the identifier of the next process of the current process. The next process ID may be set with a plurality of next process identifiers. In this case, it means that the process branches at the next process and is processed in parallel.

The maintenance schedule information 11d is an example of second information that defines conditions for each of a plurality of maintenance tasks, and is information in which various types of information used for determining maintenance schedules are set for each maintenance task.

FIG. 8 is a diagram showing an example of maintenance schedule information 11d. As shown in FIG. 8, the maintenance schedule information 11d includes, for example, a work ID, which is an example of identifiers of maintenance work, work content, target equipment ID, person in charge ID, work days, start deadline, completion deadline, and The item of scheduled work start date may be included.

For the work content, the target equipment for the maintenance work and the content of the maintenance work may be set. The target equipment ID is an example of the identifier of the equipment that is the target of maintenance work. The target equipment ID may be an ID common to the equipment used in the treatment process information 11a (see FIG. 7). The person-in-charge ID is an example of an identifier of a maintenance worker who performs maintenance work. The number of work days is an example of the number of days required from the start of maintenance work to the completion thereof.

The start deadline and completion deadline are examples of the date on which maintenance work should be started and the date on which maintenance work should be completed. The start deadline and the completion deadline may be, for example, deadlines predetermined by law or the like, or may be set in advance according to the maintenance work execution cycle, past execution timings, and the like.

The scheduled work start date is an example of a scheduled start date for maintenance work. A tentative scheduled date (for example, start deadline (+α), or completion deadline minus work days (−α)) may be set in advance as the scheduled work start date. In one embodiment, a maintenance schedule is created by updating the scheduled work start date through processing described later.

(Example of operation of creation device 1)
First, with reference to FIG. 9, an example of the overall operation of creating a maintenance schedule by the creation device 1 will be described.

As illustrated in FIG. 9, the creation device 1 creates a network diagram 11b of the product flow from the processing process information 11a (step S1).

Here, if the processing process information 11a shown in FIG. 7 is visualized as a directed graph in which the steps are connected by arrows pointing from the previous step to the next step, it can be seen that the processing flow as illustrated in FIG. 10 is described. .

FIG. 10 shows an example in which the processing process information 11a of the product ID "ABC00123" illustrated in FIG. 7 is visualized. As illustrated in FIG. 10, the process PR not designated as the next process ID in FIG. 7 is the first process PR, that is, the process A (ID: 1). Also, in FIG. 7, the process PR with multiple designated next process IDs is the process PR that branches to parallel processing in the next process, that is, the process B (ID: 2). Furthermore, in FIG. 7, a plurality of process PRs designated as next process IDs are the merging process PR, that is, the process E (ID: 7).

FIG. 11 is a diagram showing an example of the network diagram 11b of the processing process of the product ID "ABC00123" illustrated in FIG. A network diagram 11b showing the flow of products may be created according to the following rules.

(i) Each process, that is, the node ND is connected by an arrow pointing to the next process.
(ii) There is a start node Ns before the first step (first step) and an end node Ne after the last step.
(iii) Each arrow carries information on the maximum amount of product that flows through the process. Note that the maximum amount of flow through each side is equivalent to the smaller one of the processing capacities of the processes on both ends. However, the maximum amount between the start node Ns and the first step is equal to the throughput of the first step, and the maximum amount between the end node Ne and the final step is equal to the throughput of the final step.

Returning to the description of FIG. 9, the creation device 1 uses the network diagram 11b to calculate the processing capacity (maximum processing capacity 11c) (Pmax) when there is no stop facility (step S2).

The creation device 1 sets 1 to the variable j (step S3). Then, the creation device 1 uses the modified network diagram 11b by setting the processing capacity of the process including the target equipment of the work wj to 0, and collects the information of the process X where the maintenance work should be performed so that the schedule overlaps with the process i. (step S4). i is one of the process IDs set in the treatment process information 11a.

Here, a maintenance work W including a plurality of works w1, . . . , wn is written as W(w1, . Note that n is an integer equal to or greater than 1 and is the number of operations included in the maintenance work W. FIG. Moreover, j is an integer greater than or equal to 1 and less than or equal to n. For example, in the maintenance schedule information 11d shown in FIG. 8, if the maintenance work for the target equipment ID: EQ01 is W, three (n=3) work IDs: T001 to T003 targeting the target equipment ID: EQ01 are: They correspond to w1 to w3, respectively.

The creation device 1 sets 1 to the variable k (step S5). Then, the creation device 1 collects work Y={y1, . Note that m is an integer of 1 or more and is the number of operations Y. Also, k is an integer greater than or equal to 1 and less than or equal to m.

Based on the maintenance schedule information 11d, the creation device 1 determines whether or not work wj and work yk are performed by different persons and can be performed on the same schedule (step S7).

If NO in step S7, the process proceeds to step S9. If YES in step S7, the maintenance schedule information 11d collects conditions for scheduled work start dates (inter-work constraints 11e) for performing work wj and work yk on overlapping schedules (step S8), and k is less than the number m of tasks Y (step S9).

If YES in step S9, the creation device 1 adds 1 to k (step S10), and the process proceeds to step S7. If NO in step S9, the creation device 1 determines whether or not j is less than the number of operations n (step S11).

If YES in step S11, the creation device 1 adds 1 to j (step S12), and the process proceeds to step S4. If NO in step S11, the creation device 1 determines the scheduled start date of each work (automatic schedule creation) (step S13), and the process ends.

Next, a configuration example of blocks 12 to 16 for executing the processing of each step described above will be described.

(Description of the network diagram creation unit 12)
The network diagram creation unit 12 is a creation unit that expresses the process using a plurality of facilities as a network diagram 11b showing the quantity of products flowing into or out of each process based on the processing process information 11a stored in the memory unit 11. is an example. Further, the network diagram creating unit 12 may store the created network diagram 11b in the memory unit 11 .

An example of a technique for creating the network diagram 11b based on the processing process information 11a by the network diagram creating unit 12 will be described below.

FIG. 12 is a flow chart showing an operation example of the network diagram creation unit 12, and FIGS. 13 and 14 are diagrams showing an example of a method of creating the network diagram 11b shown in FIG. The processes illustrated in FIGS. 12 to 14 correspond to the process of step S1 in FIG.

As illustrated in FIG. 12, the network diagram creation unit 12 adds a start node Ns and an end node Ne (step S21; see procedure A in FIG. 13).

In the processing process information 11a, the network diagram creation unit 12 sets a process that has no next process to X (in the procedure B of FIG. 13, sets the process E to X={E}), adds a node ND of the process X, An arrow connects the added node ND and the end node Ne (step S22). In addition, the network diagram creation unit 12 sets the maximum flow rate of each connected arrow to a value equal to the processing capacity of the process corresponding to the base of the arrow (“30” in process E in procedure B of FIG. 13) (step S23). .

In the processing process information 11a, the network diagram creation unit 12 searches for a process Y having one of the processes X (process E in the procedure C of FIG. 13) as the next process (step S24), and determines whether the process Y exists. (step S25).

If YES in step S25, the network diagram creating unit 12 adds the node ND of the process Y (Y={D1, D2} in the procedure C of FIG. 13), the added node ND and the next process (FIG. 13 In step C of step E), the node ND is connected (step S26).

Further, the network diagram creating unit 12 sets the maximum flow rate of each connected arrow to a value equal to the smaller one of the processing capacities of the processes at both ends (step S27). For example, in procedure C of FIG. 13, the network diagram creation unit 12 sets the maximum flow rate of the arrow from process D1 to process E to a value equal to "10" in process D1, and the maximum flow rate of the arrow from process D2 to process E. Set the flow rate equal to "15" in step D2.

Then, the network diagram creation unit 12 sets Y to X (X={D1, D2} in procedure D of FIG. 13) (step S28), and the process proceeds to step S24.

Following procedure D in FIG. 13, the network diagram creating unit 12 executes the following processes in a loop of steps S24 to S28.

In the procedure E of FIG. 14, the network diagram creation unit 12 searches for a process having one of process X={D1, D2} as the next process, and sets Y={C1, C2}. Then, the network diagram creation unit 12 adds the node ND of the process Y and connects the added node ND and the next process. In addition, the network diagram creation unit 12 sets the maximum flow rate of each connected arrow to a value equal to the smaller one of the processing capacities of the processes on both ends. Then, the network diagram creation unit 12 sets X=Y={C1, C2}.

Further, in procedure F of FIG. 14, the network diagram creation unit 12 searches for a process Y={B} having either of process X={C1, C2} as the next process, and executes the same processing as in procedure E. do. Furthermore, in procedure G of FIG. 14, the network diagram creation unit 12 searches for process Y={A} having process X={B} as the next process, and executes the same process as procedure E or F. FIG.

Next, in the procedure H of FIG. 14, the network diagram creating unit 12 searches for a process Y having a process X={A} as the next process, but such a process Y does not exist. That is, it becomes NO at step S25 of FIG.

In this case, the network diagram creating unit 12 connects the start node Ns and the process X (process A in the procedure I of FIG. 14) with an arrow directed to the process X (step S29). Then, the network diagram creation unit 12 sets the maximum flow rate of each connected arrow to a value equal to the processing capacity of the process X at the tip of the arrow ("30" of process A in procedure I of FIG. 14) (step S30), the current network diagram 11b is stored in the memory unit 11, and the process ends.

(Description of Maximum Processing Capacity Calculation Unit 13)
The maximum processing capacity calculation unit 13 calculates the maximum flow rate of products flowing from the start node Ns to the end node Ne in the network diagram 11b created by the network diagram creation unit 12 . In other words, the maximum processing capacity calculation unit 13 is an example of a first acquisition unit that acquires the first processing capacity of a process in a state where equipment is not stopped, based on the processing process information 11a.

Further, the maximum processing capacity calculation unit 13 may store the calculated maximum flow rate in the memory unit 11 as the maximum processing capacity 11c (Pmax) of the processing process.

The maximum flow rate through network diagram 11b can be calculated, for example, by a ramp-up algorithm such as the Ford-Falkerson algorithm.

An example of a calculation method of the maximum processing capacity 11c by the maximum processing capacity calculation unit 13 will be described below.

FIG. 15 is a flow chart showing an operation example of the maximum processing capacity calculator 13, and FIGS. 16 and 17 are diagrams showing an example of a method of calculating the maximum processing capacity 11c based on the network diagram 11b shown in FIG. The processes illustrated in FIGS. 15 to 17 correspond to the process of step S2 in FIG.

As illustrated in FIG. 15, the maximum processing capacity calculation unit 13 sets the current flow of the network diagram 11b shown in FIG. 11 to the flow rate of all arrows=0 (step S31; see procedure A in FIG. 16).

The maximum processing capacity calculation unit 13 creates a network (residual network) in which arrows pointing in opposite directions to the current flow are indicated (step S32; see the dashed arrow in procedure B in FIG. 16).

Next, the maximum processing capacity calculator 13 searches for a route from the end node Ne to the start node Ns in the residual network (step S33; see the dashed-dotted line arrow in procedure C in FIG. 16).

The maximum processing capacity calculator 13 determines whether or not there is a route (step S34). In the case of YES in step S34, the maximum processing capacity calculation unit 13 adopts one route from the end node Ne to the start node Ns, and updates the current flow using the route (step S35; procedure in FIG. 16 D), and the process proceeds to step S32. Procedure D in FIG. 16 shows an example in which the maximum processing capacity calculation unit 13 flows "10", which is the minimum flow rate on the route, in the opposite direction to the residual network.

Following procedure D in FIG. 16, the maximum processing capacity calculator 13 executes the following processes in the loop of steps S32 to S35.

In procedure E of FIG. 17, the maximum processing capacity calculation unit 13 creates a residual network again and searches for a route (see one-dot chain line) from the end node Ne to the start node Ns. Then, in the procedure F of FIG. 17, the maximum processing capacity calculation unit 13 causes the flow rate "10" to flow in the opposite direction to the route of the procedure C of FIG. 16 to update the current flow. Note that the maximum processing capacity calculation unit 13 obtains the flow rate "10" for the arrows (for example, the start node Ns to the process B and the process E to the end node Ne) by the search in the procedure E. Add the flow rate "10".

Next, in procedure G of FIG. 17, the maximum processing capacity calculation unit 13 creates a residual network again, but there is no path from the end node Ne to the start node Ns (see dashed line). That is, it becomes NO in step S34 of FIG.

In this case, the current flow is the maximum flow path, and the flow rate entering the end node Ne (“20” in procedure H in FIG. 17) is the maximum flow rate. Therefore, the maximum processing capacity calculation unit 13 determines the maximum flow as the maximum processing capacity 11c (Pmax) of this process (step S36; see procedure H in FIG. 17), stores the maximum processing capacity 11c in the memory unit 11, Processing ends.

(Description of inter-work constraint creation unit 14)
The inter-work constraint creation unit 14 is an example of a constraint creation unit that creates a constraint on the start date of maintenance work based on the maintenance schedule information 11d for each pair of maintenance work that can be performed on overlapping schedules.

For example, the inter-work constraint creation unit 14 extracts a combination of two works based on the processing process information 11a, the network diagram 11b, and the maintenance schedule information 11d, and generates the inter-work constraint 11e regarding the start date of the work between the jobs. You can

The combination of the two extracted works is determined by the collection processing of “process X” and “maintenance work Y” and the executability confirmation processing of “work wj” and “work yk”, which will be described below. good.

(collection processing)
An example of collection processing by the inter-work constraint creation unit 14 will be described below. FIG. 18 is a diagram showing an example of collection processing by the inter-work constraint creation unit 14. As shown in FIG. The processing illustrated in FIG. 18 corresponds to the processing of steps S3 to S6, S11, and S12 in FIG.

When performing work wj, the inter-work constraint creation unit 14 collects processes X that lead to a reduction in opportunity loss cost if work is performed on a schedule that overlaps with work wj. For example, the inter-task constraint creation unit 14 calculates the throughput using the modified network diagram 11b by setting the throughput of the process i to 0. FIG.

As an example, the work-to-work constraint creation unit 14 creates a network diagram 11b when the processing capacity of the process C1 in which the target equipment of the work wj is installed is set to 0 in the procedure A of FIG.

18, the inter-work constraint creation unit 14 calculates the maximum processing capacity of the network (one point see dashed line).

At this time, the process X where the processing amount is 0 is the same as when the equipment is stopped. In other words, it means that the process X whose processing amount is 0 can reduce the opportunity loss cost by performing the work on the same schedule as the process i, compared to the case of performing the work on a different day.

Therefore, the work-to-work constraint creating unit 14 refers to the processing process information 11a and the maintenance schedule information 11d, and collects work Y={y1, . For example, as shown in procedure C of FIG. 18 , the inter-work constraint creation unit 14 collects, as a process X, processes with 0 input/output.

In the example of FIG. 18, when the process C1 using the equipment used: EQ04-1 is stopped, the input/output of the process D1 using the equipment used: EQ05 becomes zero. Therefore, the inter-work constraint creation unit 14 determines that the process D1 is a process X that should be performed so that the schedule overlaps with the process C1, and collects such information.

(executability confirmation process)
An example of executability confirmation processing by the inter-work constraint creation unit 14 will be described below. FIG. 19 is a diagram showing an example of executability confirmation processing by the inter-operation constraint creation unit 14, and FIG. 20 is a diagram showing an example of the inter-operation constraint 11e. The processes illustrated in FIGS. 19 and 20 correspond to the processes of steps S7 to S10 in FIG.

Based on the information of work W and the information of work Y related to the facilities used in process X, which are collected in the collection process, the inter-work constraint creation unit 14 selects schedules in which the persons in charge of work wj and work yk are different and overlap. based on the maintenance schedule information 11d.

Then, the inter-work constraint creation unit 14 creates a constraint (inter-work constraint 11e) on the scheduled work start date between the tasks if the work can be executed on the overlapping schedule.

For example, as shown in FIG. 19, in the maintenance schedule information 11d shown in FIG. Determine whether the IDs match. In the example of FIG. 19, since the person-in-charge IDs are W003 and W004, respectively, the work constraint creation unit 14 determines that the persons in charge are different.

Also, as shown in FIG. 19, the inter-work constraint creation unit 14 sets the start dates of the works T006 and T008 to S6 and S8, and the work days of the works T006 and T008 to d6 and d8. It is determined whether or not the dates overlap as indicated by .

19, the inter-work constraint creation unit 14 may determine that the schedules overlap if the start date of work wj is between the start date and completion date of work yk. Alternatively, in reference symbol B in FIG. 19, the inter-work constraint creation unit 14 may determine that the schedules overlap if the start date of work yk is between the start date and the completion date of work wj. Codes A and B are mutually inverse patterns.

The inter-work constraint creation unit 14 may create inter-work constraints 11e and store them in the memory unit 11, as illustrated in FIG. The work constraint 11e includes a table (matrix) 11e-1 indicating whether or not there is a constraint for each combination of two tasks, and a work constraint 11e-2 (for example, S8≦S6≦S8+d8).

As described above, the executability confirmation process can identify pairs of maintenance work that can be performed on overlapping schedules, and the collection process can identify maintenance work pairs that reduce the opportunity loss cost compared to performing them on different schedules. can. In this way, the inter-work constraint creation unit 14 extracts a plurality of maintenance work pairs that can be executed on overlapping schedules and that have a lower opportunity loss cost than when the schedules are staggered. be.

In the example described above, the inter-work constraint creation unit 14 determines whether or not the persons in charge match, but the present invention is not limited to this. For example, the inter-work constraint creation unit 14 determines that, in addition to or instead of matching the person in charge, fixtures such as tools and equipment (such as cranes) used to perform the work are at least between work wj and work yk. It may be determined whether or not a part matches.

(Description of the schedule creation unit 15)
The schedule creation unit 15 repeatedly executes schedule creation and evaluation while switching between valid and invalid for each combination of two tasks in the inter-operation constraint 11e created by the inter-operation constraint creation unit 14, thereby reducing the maintenance cost. Create a maintenance schedule. The creation of the maintenance schedule by the schedule creation unit 15 may be, for example, updating the "scheduled work start date" of the maintenance schedule information 11d.

In other words, the schedule creation unit 15 is an example of an execution unit that creates a maintenance schedule and calculates maintenance costs while switching between validity and invalidity of each of a plurality of constraints.

For example, the schedule creation unit 15 repeats slightly changing the current state (neighborhood search) to find the optimal solution ( Search for the best work start date).

An example of maintenance schedule creation processing by the schedule creation unit 15 will be described below. FIG. 21 is a flowchart showing an example of maintenance schedule creation processing by the schedule creation unit 15, and FIGS. 22 to 24 are diagrams showing an example of a maintenance schedule creation method. The processes illustrated in FIGS. 21 to 24 correspond to at least part of the process of step S13 in FIG.

As exemplified in FIG. 21, the schedule creation unit 15 nullifies all the inter-work restrictions 11e (step S41), creates the initial values of the scheduled start dates of all tasks, for example, ” is set to an initial value (step S42).

The schedule creation unit 15 sets the maintenance cost of the current schedule calculated by the maintenance cost determination unit 16, which will be described later, as the best plan (step S43), and sets the number of iterations I (I is an integer equal to or greater than 1) to 0 ( step S44).

The schedule creation unit 15 slightly changes the ratio of scheduled work start dates (step S45), and determines whether or not the number of constraint violations is greater than before the change (step S46).

In the case of YES in step S46, the schedule creation unit 15 restores the ratio of scheduled work start dates to the state before change (step S47), and the process proceeds to step S50.

If NO in step S46, the maintenance cost determination unit 16, which will be described later, calculates the maintenance cost of the schedule (step S48), and the schedule creation unit 15 determines whether the maintenance cost is lower than before the change (step S48). S49).

If NO in step S49, the process proceeds to step S47. On the other hand, if YES in step S49, the schedule creation unit 15 determines whether or not I is smaller than the upper limit M of repetition times (step S50).

If YES in step S50, the schedule creation unit 15 adds 1 to I (step S51), and the process proceeds to step S45.

Note that the processing of steps S44 to S51 shown in FIG. 21 is the neighborhood search processing by the schedule creation unit 15, and may be realized by a known technique.

In the case of NO in step S50, the schedule creation unit 15 determines whether or not the maintenance cost of the current plan is smaller than the best plan (step S52).

In the case of NO in step S52, the schedule creation unit 15 invalidates the inter-work constraint 11e added last, if any (step S53). Then, the schedule creation unit 15 collects invalid inter-work constraints 11e related to work that is not executed on a schedule that overlaps with any work in the schedule (step S54).

For example, the schedule creation unit 15 extracts work (work circled with a solid line) that is not executed on a schedule that overlaps with any work shown in the schedule of procedure A in FIG. 22 . In addition, the schedule creation unit 15 collects (identifies) invalid constraints (constraints indicated by black circles in the table 11e-1 of procedure B in FIG. 22) in the inter-work constraints 11e regarding the extracted work.

The schedule creation unit 15 validates one or more of the collected constraints (step S55), invalidates inter-work constraints 11e that conflict with the newly validated constraints (step S56), and the process proceeds to step S44.

For example, as shown in procedure C of FIG. 23, the schedule creation unit 15 selects and activates one of the collected inter-task constraints 11e according to the uniform probability distribution. In the example of procedure C, the schedule creation unit 15 selects and validates the constraint that overlaps tasks T010 and T002.

As a result, when the schedule creation unit 15 performs the neighborhood search (local search) again to generate a schedule, for example, as shown in procedure D in FIG. can be reduced.

Note that if too many inter-work constraints 11e are added, an unsatisfiable state may occur. If there is a contradiction between the newly validated inter-operation constraint 11e and the already valid inter-op constraint 11e, the schedule creation unit 15, as shown in step S56 in FIG. Disable inter-work constraint 11e.

For example, the schedule creation unit 15 extracts all already valid inter-task constraints Y that are related to two tasks related to the newly activated inter-task constraint X. Then, the schedule creation unit 15 performs mathematical formula processing with the constraint X and the constraint Y, and determines whether or not the constraint can be satisfied by the mathematical formula processing. If the constraint cannot be satisfied, the scheduler 15 nullifies the constraint Y.

For example, as shown in the procedure E of FIG. 24, it is assumed that the following (1) and (2) exist as already valid inter-work constraints and the following (3) is newly validated.

(1) S2≤S10≤S2+d2
(2) S10≤S2≤S10+d10
(3) S9≤S2≤S9+d9

In this case, if the constraints on T2 and T9 are mathematically processed, S9≤S2=S10≤S9+d9, and the workers need to perform the same tasks T9 and T10 at the same time, creating a contradiction in the inter-task constraint 11e.

Therefore, in the example of procedure E, the schedule creation unit 15 invalidates inter-work constraints (1) and (2).

Returning to the description of FIG. 21, if YES in step S52, the schedule creation unit 15 adopts the current plan as the best plan (step S58), and determines whether or not the determination has been completed (step S59). As a condition for determining whether or not to end the determination, for example, the number of executions of the schedule creation process (which may be the number of determinations in step S59) is equal to or greater than a predetermined threshold, or the amount of change in maintenance cost is equal to or less than a predetermined threshold. and the like.

If NO in step S59, the process proceeds to step S54. On the other hand, if YES in step S59, the process ends.

It should be noted that the processing of steps S53 to S56 shown in FIG. 21 is search space correction processing (step S60) specialized for maintenance schedule creation.

(Description of Maintenance Cost Determination Unit 16)
The maintenance cost determining unit 16 calculates the maintenance cost of the maintenance schedule based on the first processing capacity (maximum processing capacity 11c) and the second processing capacity of the process when any one of the plurality of facilities is stopped. It is an example of the calculation part which does.

As shown in FIG. 6, the maintenance cost determination unit 16 may exemplarily include the functions of a processing capacity calculation unit 16a, an opportunity loss cost calculation unit 16b, and a maintenance cost calculation unit 16c.

The processing capacity calculation unit 16a is an example of a second acquisition unit that acquires a second processing capacity of a process when one of a plurality of pieces of equipment is stopped based on the processing process information 11a. Calculate the processing capacity (second processing capacity).

The opportunity loss cost calculation unit 16b calculates the daily opportunity loss cost based on the difference between the maximum processing capacity and the processing capacity when the equipment is stopped.

The maintenance cost calculator 16c calculates the maintenance cost of the created maintenance schedule from the sum of the daily opportunity loss costs.

An example of maintenance cost determination (calculation) processing by the maintenance cost determination unit 16 will be described below. In the following description, all dates in the period indicated in the maintenance schedule are indicated by D={d1, .

FIG. 25 is a flow chart showing an example of maintenance cost determination processing by the maintenance cost determination unit 16, and FIG. 26 is a diagram showing an example of a daily processing capacity calculation method. The processes illustrated in FIGS. 25 and 26 correspond to at least a part of the process of step S13 in FIG. 9, a part of step S43 in FIG. 21, and the process of step S48 in FIG.

As illustrated in FIG. 25, the maintenance cost determining unit 16 sets 1 to the variable i (step S61).

The processing capacity calculation unit 16a modifies the network diagram 11b to take into consideration the equipment stop based on the maintenance schedule information 11d, and calculates the processing capacity pi on the date di (step S62).

For example, on date di, the processing capacity of the process is assumed to be 0 because the process including the target equipment for the work to be performed on that day cannot be processed due to the effects of the equipment stoppage. The work to be performed on that day is set in the maintenance schedule information 11d.

Therefore, the processing capacity calculator 16a corrects the network diagram 11b by setting the processing capacity of the process to 0 based on the maintenance schedule information 11d. Then, the processing capacity calculator 16a uses the modified network diagram 11b to calculate the maximum processing capacity by the same method as the calculation of the maximum processing capacity 11c described with reference to FIGS. 15 to 17. FIG. The processing capacity calculator 16a sets the calculated maximum processing capacity as the processing capacity pi of the process on date di.

For example, as shown in FIG. 26, assume the case of date di=2019/3/11 (target equipment ID: one work (T006) related to EQ04-1 is scheduled).

The processing capacity calculation unit 16a sets the processing capacity of the process using the facility EQ04-1 to 0 as shown in the upper left of FIG. 26, and sets the processing capacity of the process C1 to 0 as shown in the lower left of FIG. create a network diagram 11b of

Further, as shown in the upper right of FIG. 26, the processing capacity calculation unit 16a calculates the maximum processing capacity of the network diagram 11b by the same method as the calculation of the maximum processing capacity 11c described with reference to FIGS. 15 to 17. do. Then, the processing capacity calculator 16a sets the maximum processing capacity to the processing capacity pi of the process on date di, as shown in the lower right of FIG.

Returning to the description of FIG. 25, the opportunity loss cost calculation unit 16b calculates the decrease rate ri of the processing capacity on the date di based on pi and Pmax (maximum processing capacity 11c) (step S63).

Here, the profit equivalent to the product that could not be manufactured due to the decline in the plant processing capacity due to the stoppage of the equipment is defined as the opportunity loss cost.

Decrease rate ri of the processing capacity of the plant on date di may be calculated by the following equation (1). In the following equation (1), Pmax is the maximum processing capacity 11c, and pi is the processing capacity on date di.

The opportunity loss cost calculator 16b uses the decrease rate ri to calculate the opportunity loss cost ci on the date di (step S64).

For example, the opportunity loss cost calculator 16b may calculate the opportunity loss cost ci on the date di using the following equation (2). In the following formula (2), N is the maximum daily production volume [pieces/day], and g is the profit per product [yen]. The maximum production amount N and profit g may be stored in advance in the memory unit 11 as maximum production amount 11f and profit 11g, respectively.

ci=riNg (2)

The opportunity loss cost calculation unit 16b repeats the process shown in FIG. 25 for all dates of the maintenance schedule period, thereby obtaining the opportunity loss cost {c1, . . . , c _Nday } for each day during the period. . Note that Nday indicates the number of days within the period of the maintenance schedule.

Returning to the description of FIG. 25, the maintenance cost calculator 16c determines whether i is smaller than x (step S65). If YES in step S65, the maintenance cost calculation unit 16c adds 1 to i (step S66), and the process proceeds to step S62.

If NO in step S65, the maintenance cost calculator 16c calculates the maintenance cost C for the entire period indicated in the schedule (step S67), and the process ends.

For example, the maintenance cost calculator 16c calculates the maintenance cost C _total during the period of the maintenance schedule. The maintenance cost C _total may be the sum of the opportunity loss cost C _loss during the maintenance period and the total cost C _task for the maintenance work, as shown in the following equation (3).

C _total = C _loss + C _task (3)

Also, the opportunity loss cost C _loss is calculated by the following equation (4) as the sum of the daily opportunity loss costs ci.

Further, the total cost C _task of the maintenance work is calculated by the following equation (5) as the sum of the costs c _task,j of the work j.

Here, the memory unit 11 may store maintenance work cost information 11i. The maintenance work cost information 11i holds the following information.

・Cost for performing work j (constant independent of maintenance implementation date): c _{1, j}
A function with arguments of the maintenance date di and the implementation deadline Dj of the work j, which is used to calculate the cost c _1,j that changes depending on the maintenance implementation date in relation to the work j: f _2,j ( di, Dj)
When considering only the residual value of the member as the cost c _2,j , and assuming that the residual value becomes 0 yen at the maintenance deadline, the function information shown in the following formula (6) is held in the maintenance work cost information 11i. .

f _2,j (di, Dj)=a(Dj−di) (6)

Also, the cost c _task,j for each task may be calculated as the sum of two costs c _1,j and c _2,j . That is, it may be calculated by the following formula (7).

c _task,j =c _1,j +c _2,j =c _1,j +f _2,j (di,Dj) (7)

With the above method, the maintenance cost calculation unit 16c calculates the total cost C _task for the maintenance work.

The maintenance cost determining unit 16 may store each calculated cost, for example, the maintenance cost C _total , the opportunity loss cost C _loss , the total cost C _task , etc., in the memory unit 11 as the cost 11h.

As described above, according to the creation device 1 according to one embodiment, it is possible to automatically create a maintenance schedule with low maintenance costs including opportunity loss costs in a short time.

In addition, it is possible to plan a schedule with a low maintenance cost.

Furthermore, by adding a constraint to reduce the opportunity loss cost, the solution search is limited to areas where good solutions exist, so the number of combinations to be tried can be reduced. Therefore, the amount of calculation can be reduced, and a good solution can be obtained in a short time. That is, it is possible to shorten the schedule creation time.

[1-4] Application Example FIG. 27 is a diagram showing a display example of maintenance schedule and maintenance cost creation results. As shown in FIG. 27, the display screen 20 may display at least one or more of the following items.

- A maintenance schedule (see symbol A) in which the maintenance schedule information 11d is visualized by a Gantt chart.
- Maintenance cost [yen] (see symbol B), which visualizes the daily opportunity loss cost {c1,..., _cNday } during the schedule period in a bar graph.
• Schedule period.
- Calculation result of the maintenance cost [yen] for the entire period.

FIG. 28 is a diagram showing a configuration example of a system 30 including the creation device 1 and a terminal 40. As shown in FIG. As shown in FIG. 28, the creator of the maintenance schedule operates the terminal 40 to input the processing process information 11a and the maintenance schedule information 11d to the creation device 1. As shown in FIG. The schedule creation unit 15 of the creation device 1 outputs the maintenance schedule information 11d (minimum maintenance cost) and transmits it to the terminal 40 by the method described above. At this time, the schedule creation unit 15 may transmit information (HTML file, graph data, etc.) for displaying the display screen 20 shown in FIG.

In this manner, the schedule creation unit 15 may specify a maintenance schedule that minimizes the maintenance cost, and output information on the specified maintenance schedule.

Note that the creation device 1 may be connected to other devices such as the terminal 40 via a network so as to be able to communicate with each other. The network may include a WAN (Wide Area Network), a LAN, or a combination thereof. A WAN may include the Internet.

As a result, the creator of the maintenance schedule can easily obtain a schedule with a low maintenance cost in a short time simply by inputting the processing process information 11a and the maintenance schedule information 11d into the creation device 1. FIG. In addition, since the obtained schedule is visualized together with the evaluation result by the creation device 1, the worker can easily grasp the appropriate maintenance schedule.

[2] Others The technique according to the embodiment described above can be modified and changed as follows.

For example, each functional block shown in FIG. 6 may be merged in any combination or divided.

[3] Supplementary Note The following Supplementary Note will be disclosed with respect to the above embodiment.

(Appendix 1)
A computer that creates maintenance schedules for each of a plurality of facilities,
Based on first information defining each step of the process using the plurality of facilities, the interrelationship between the steps, and the throughput of each step, the first step of the process without facility stoppage is performed. get processing power,
Acquiring a second processing capacity of the process when one of the plurality of facilities is stopped based on the first information;
calculating a maintenance cost of the maintenance schedule based on the first processing capacity and the second processing capacity;
creating a constraint on the start date of a maintenance job for each pair of maintenance jobs that can be performed on overlapping schedules based on second information defining conditions for each of the plurality of maintenance jobs;
creating the maintenance schedule and calculating the maintenance cost while switching between enabling and disabling each of the plurality of constraints;
A maintenance schedule creation program that causes the process to be executed.

(Appendix 2)
The calculation of the maintenance cost is
calculating an opportunity loss cost for each day of the process based on the difference between the first processing capacity and the second processing capacity;
calculating the maintenance cost based on the sum of the opportunity loss costs for each day;
A program for creating a maintenance schedule according to appendix 1.

(Appendix 3)
Creating the constraint includes:
Extracting a plurality of pairs of maintenance work that can be performed on overlapping schedules and that have a lower opportunity loss cost than when the schedules are staggered, and
generating a constraint on the maintenance work start date for each of the extracted pairs;
A program for creating a maintenance schedule according to appendix 2.

(Appendix 4)
to the computer;
representing the process as a network diagram showing the quantity of products flowing into or out of each process based on the first information;
Obtaining the first processing capacity and the second processing capacity based on the network diagram;
4. A program for creating a maintenance schedule according to any one of Appendices 1 to 3, which executes a process.

(Appendix 5)
to the computer;
When the quantity of products flowing in or out of any of the first processes in the network diagram is 0, there is a second process in which the quantity of products flowing in or out is 0, creating the constraint for a pair of the first and second maintenance work when the first maintenance work for the process and the second maintenance work for the second process can be performed on an overlapping schedule;
The maintenance schedule creation program according to appendix 4, which causes the process to be executed.

(Appendix 6)
to the computer;
identifying the maintenance schedule that minimizes the maintenance cost;
outputting information about the identified maintenance schedule;
6. A program for creating a maintenance schedule according to any one of Appendices 1 to 5, which causes the process to be executed.

(Appendix 7)
A computer that creates maintenance schedules for each of a plurality of facilities,
Based on first information defining each step of the process using the plurality of facilities, the interrelationship between the steps, and the throughput of each step, the first step of the process without facility stoppage is performed. get processing power,
Acquiring a second processing capacity of the process when one of the plurality of facilities is stopped based on the first information;
calculating a maintenance cost of the maintenance schedule based on the first processing capacity and the second processing capacity;
creating a constraint on the start date of a maintenance job for each pair of maintenance jobs that can be performed on overlapping schedules based on second information defining conditions for each of the plurality of maintenance jobs;
creating the maintenance schedule and calculating the maintenance cost while switching between enabling and disabling each of the plurality of constraints;
How to create a maintenance schedule.

(Appendix 8)
The calculation of the maintenance cost is
calculating an opportunity loss cost for each day of the process based on the difference between the first processing capacity and the second processing capacity;
calculating the maintenance cost based on the sum of the opportunity loss costs for each day;
A method for creating a maintenance schedule according to appendix 7.

(Appendix 9)
Creating the constraint includes:
Extracting a plurality of pairs of maintenance work that can be performed on overlapping schedules and that have a lower opportunity loss cost than when the schedules are staggered, and
generating a constraint on the maintenance work start date for each of the extracted pairs;
The method for creating a maintenance schedule according to appendix 8.

(Appendix 10)
the computer
representing the process as a network diagram showing the quantity of products flowing into or out of each process based on the first information;
Obtaining the first processing capacity and the second processing capacity based on the network diagram;
A method for creating a maintenance schedule according to any one of Appendices 7 to 9.

(Appendix 11)
the computer
When the quantity of products flowing in or out of any of the first processes in the network diagram is 0, there is a second process in which the quantity of products flowing in or out is 0, creating the constraint for a pair of the first and second maintenance work when the first maintenance work for the process and the second maintenance work for the second process can be performed on an overlapping schedule;
The method for creating a maintenance schedule according to appendix 10.

(Appendix 12)
The computer
identifying the maintenance schedule that minimizes the maintenance cost;
outputting information about the identified maintenance schedule;
A method for creating a maintenance schedule according to any one of Appendices 7 to 11.

(Appendix 13)
A maintenance schedule creation device for creating a maintenance schedule for each of a plurality of facilities,
First information defining each step of the process using the plurality of facilities, the interrelationship between the steps, and the processing capacity of each step, and second information defining conditions for each of the plurality of maintenance operations. a storage unit that stores information; and
a first acquisition unit that acquires a first processing capacity of the process without equipment stoppage based on the first information;
a second acquisition unit that acquires a second processing capacity of the process when one of the plurality of pieces of equipment is stopped based on the first information;
a calculation unit that calculates a maintenance cost of the maintenance schedule based on the first processing capacity and the second processing capacity;
a constraint creation unit that creates a constraint on the start date of maintenance work for each pair of maintenance work that can be executed on overlapping schedules based on second information that defines conditions for each of a plurality of maintenance work;
an execution unit that executes creation of the maintenance schedule and calculation of the maintenance cost while switching between validity and invalidity of each of the plurality of constraints;
A maintenance schedule creation device.

(Appendix 14)
The calculation unit
calculating an opportunity loss cost for each day of the process based on the difference between the first processing capacity and the second processing capacity;
calculating the maintenance cost based on the sum of the opportunity loss costs for each day;
13. The maintenance schedule creation device according to appendix 13.

(Appendix 15)
The constraint creation unit
Extracting a plurality of pairs of maintenance work that can be performed on overlapping schedules and that have a lower opportunity loss cost than when the schedules are staggered, and
generating a constraint on the maintenance work start date for each of the extracted pairs;
15. The maintenance schedule creation device according to appendix 14.

(Appendix 16)
a creation unit that expresses the process as a network diagram showing the quantity of products flowing into or out of each process based on the first information;
The first acquisition unit and the second acquisition unit acquire the first processing capability and the second processing capability, respectively, based on the network diagram.
The maintenance schedule creation device according to any one of Appendices 13 to 15.

(Appendix 17)
The constraint creation unit
When the quantity of products flowing in or out of any of the first processes in the network diagram is 0, there is a second process in which the quantity of products flowing in or out is 0, creating the constraint for a pair of the first and second maintenance work when the first maintenance work for the process and the second maintenance work for the second process can be performed on an overlapping schedule;
17. The maintenance schedule creation device according to appendix 16.

(Appendix 18)
The execution unit
identifying the maintenance schedule that minimizes the maintenance cost;
outputting information about the identified maintenance schedule;
Create a maintenance schedule according to any one of Appendices 13 to 17.

1 Maintenance Schedule Creation Device 10 Computer 11 Memory Section 11a Processing Process Information 11b Network Diagram 11c Maximum Processing Capacity 11d Maintenance Schedule Information 11e Inter-work Restriction 11f Maximum Production Volume 11g Profit 11h Cost 11i Maintenance Work Cost Information 12 Network Diagram Creation Section 13 Maximum Processing Capacity calculation unit 14 Work constraint creation unit 15 Schedule creation unit 16 Maintenance cost determination unit 16a Processing capacity calculation unit 16b Opportunity loss cost calculation unit 16c Maintenance cost calculation unit 20 Display screen 30 System 40 Terminal

Claims (8)

A computer that creates maintenance schedules for each of a plurality of facilities,
Based on first information defining each step of the process using the plurality of facilities, the interrelationship between the steps, and the throughput of each step, the first step of the process without facility stoppage is performed. a first process of acquiring processing power;
obtaining a second processing capacity of the process in a stopped state of any one of the plurality of facilities based on the first information , and performing the maintenance based on the first processing capacity and the second processing capacity; a second process of calculating and evaluating schedule maintenance costs;
A maintenance schedule creation program causing the execution of
Based on second information that defines conditions for each of a plurality of maintenance tasks, a pair of maintenance tasks that can be executed on overlapping schedules among the maintenance tasks included in the maintenance schedule is created with a constraint that both schedules overlap. death,
A program for creating a maintenance schedule, characterized in that the second process is repeatedly executed while switching validity or invalidity of each of the plurality of constraints. The second processing is
calculating an opportunity loss cost for each day of the process based on the difference between the first processing capacity and the second processing capacity;
calculating the maintenance cost based on the sum of the opportunity loss costs for each day;
2. A program for creating a maintenance schedule according to claim 1 , characterized by including processing . Creating the constraint includes:
Extracting a plurality of pairs of maintenance work that can be performed on overlapping schedules and that have a lower opportunity loss cost than when the schedules are staggered, and
Generate as the constraint that both schedules overlap for each of the extracted pairs,
3. A program for creating a maintenance schedule according to claim 2 , characterized by including processing . to the computer;
representing the process as a network diagram showing the quantity of products flowing into or out of each process based on the first information;
Obtaining the first processing capacity and the second processing capacity based on the network diagram;
4. The program for creating a maintenance schedule according to any one of claims 1 to 3, characterized by causing a process to be executed. to the computer;
When the quantity of products flowing in or out of any of the first processes in the network diagram is 0, there is a second process in which the quantity of products flowing in or out is 0, When the first maintenance work for the process and the second maintenance work for the second process can be performed on overlapping schedules, for the pair of the first maintenance work and the second maintenance work , the schedules of both are overlapped. Create as a constraint,
5. The program for creating a maintenance schedule according to claim 4, causing a process to be executed. to the computer;
identifying the maintenance schedule that minimizes the maintenance cost;
outputting information about the identified maintenance schedule;
6. The program for creating a maintenance schedule according to any one of claims 1 to 5, characterized by causing a process to be executed. A computer that creates maintenance schedules for each of a plurality of facilities,
Based on first information defining each step of the process using the plurality of facilities, the interrelationship between the steps, and the throughput of each step, the first step of the process without facility stoppage is performed. a first process of acquiring processing power;
obtaining a second processing capacity of the process in a stopped state of any one of the plurality of facilities based on the first information , and performing the maintenance based on the first processing capacity and the second processing capacity; a second process of calculating and evaluating schedule maintenance costs;
A method for creating a maintenance schedule, comprising:
Based on second information that defines conditions for each of a plurality of maintenance tasks, a pair of maintenance tasks that can be executed on overlapping schedules among the maintenance tasks included in the maintenance schedule is created with a constraint that both schedules overlap. death,
A method for creating a maintenance schedule, wherein the second process is repeatedly executed while switching validity or invalidity of each of the plurality of constraints. A maintenance schedule creation device for creating a maintenance schedule for each of a plurality of facilities,
First information defining each step of the process using the plurality of facilities, the interrelationship between the steps, and the processing capacity of each step, and second information defining conditions for each of the plurality of maintenance operations. a storage unit that stores information; and
a first processing unit that executes a first process of acquiring a first processing capacity of the process in a state where equipment is not stopped, based on the first information;
obtaining a second processing capacity of the process in a stopped state of any one of the plurality of facilities based on the first information, and performing the maintenance based on the first processing capacity and the second processing capacity; a second processing unit that executes a second process of calculating and evaluating the maintenance cost of the schedule;
Based on second information that defines conditions for each of a plurality of maintenance tasks, a pair of maintenance tasks that can be executed on overlapping schedules among the maintenance tasks included in the maintenance schedule is created with a constraint that both schedules overlap. a constraint creation unit that
an execution unit that causes the second processing unit to repeatedly execute the second process while switching between validity and invalidity of each of the plurality of constraints;
A maintenance schedule creation device, comprising :

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