Automatic shift generation device, automatic shift generation method, and automatic shift generation program

Abstract

To provide an automatic shift generation device, an automatic shift generation method, and an automatic shift generation program capable of reducing time and labor for a user to manually correct a shift table.SOLUTION: The automatic shift generation device includes an acquisition unit 211, a generation unit 212, an evaluation unit 213, and an adjustment unit 214. The acquisition part acquires a plurality of rules related to shift and the importance of each rule. The generation part generates a plurality of shift tables of the next generation by evolving a plurality of shift tables as a plurality of individuals of the current generation to a plurality of shift tables of the next generation on the basis of the rule and the importance by using a genetic algorithm for evolving the plurality of individuals of the current generation to the plurality of individuals of the next generation. The evaluation unit evaluates the degree of achievement of the rule for each of the generated shift tables. The adjustment unit specifies a rule whose degree of achievement is to be improved among the plurality of rules, and adjusts the degrees of importance of the rules other than the specified rule to be lowered or prompts the user to lower the degrees of importance of the rules other than the specified rule.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to an automatic shift generation device, an automatic shift generation method, and an automatic shift generation program. [Background technology]

[0002] Hospitals, nursing homes, factories, hotels, and other facilities generally require 24-hour service, so they employ two- or three-shift systems. In shift work, staff work schedules are managed by a work schedule created by an administrator. A work schedule (hereafter simply referred to as a "shift schedule") is a list showing the shift assignments for each staff member each day during a specified period, and is assigned a unique shift symbol to represent the shift assignment. The specified period is typically 30 days. In nursing home shift schedules, shift symbols include, for example, "night" for night shift, "day" for day shift, "early" for early shift, "late" for late shift, "morning" for after a night shift, and "public" for public holiday. When there are a large number of staff members working shifts or a large number of shift symbols, the number of possible shift schedule patterns becomes enormous. Furthermore, creating a shift schedule requires considering not only numerous shift work rules but also the requests of multiple staff members regarding work and holidays. Creating a shift schedule that satisfies these constraints and requests by hand is not an easy task.

[0003] In this regard, techniques have been proposed to reduce the burden on managers in creating shifts (schedules).For example, Patent Document 1 below discloses a solution search device that uses a genetic algorithm to search for an optimal solution that satisfies multiple constraints for the task of creating a charging schedule for secondary batteries. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-160399 Summary of the Invention [Problem to be solved by the invention]

[0005] However, although the solution search device in Patent Document 1 discloses that it searches for an optimal solution that satisfies multiple constraints (rules), it does not take into consideration the weights (importance) of the multiple constraints. Therefore, when it is difficult to simultaneously satisfy constraints with different importance, an individual (charging schedule) is not necessarily generated so that the constraints with higher importance are satisfied, and there is a possibility that an optimal solution will not be obtained.

[0006] In this case, the user must manually modify the generated individual (charging schedule) so that the constraints are satisfied. However, when modifying shift schedules in nursing care facilities, it can be difficult to do so manually if there are a large number of staff members or the rules are complex. Even if manual modification is possible, it can take a lot of time and effort.

[0007] The present invention has been made in consideration of the above circumstances, and aims to provide an automatic shift generation device, an automatic shift generation method, and an automatic shift generation program that can reduce the time and effort required for users to manually modify shift tables. [Means for solving the problem]

[0008] The above-mentioned problems of the present invention are solved by the following means.

[0009] (1) An automatic shift generation device having: an acquisition unit that acquires multiple rules related to shifts and the importance of each of the rules; a generation unit that generates multiple next-generation shift tables by evolving multiple shift tables as multiple individuals of the current generation into multiple next-generation individuals based on the rules and the importance using a genetic algorithm that evolves multiple individuals of the current generation into multiple next-generation individuals; an evaluation unit that evaluates the degree of achievement of the rules for each of the generated shift tables; and an adjustment unit that identifies rules of which the degree of achievement should be improved from the multiple rules, and adjusts the importance of rules other than the identified rules to lower them, or prompts a user to lower the importance.

[0010] (2) The automatic shift generation device described in (1) above, wherein the adjustment unit identifies a rule whose achievement level does not meet a predetermined standard as a rule whose achievement level should be improved.

[0011] (3) The automatic shift generation device described in (1) above, wherein the adjustment unit identifies a rule designated by a user as a rule for which the achievement level should be improved.

[0012] (4) The automatic shift generation device described in (1) above, wherein the adjustment unit identifies rules whose achievement level does not meet a predetermined standard and whose importance is equal to or greater than a specified value as rules whose achievement level should be improved.

[0013] (5) The automatic shift generation device according to any one of (1) to (4) above, wherein the adjustment unit reduces the importance by subtracting a predetermined value from the importance.

[0014] (6) The automatic shift generation device described in any one of (1) to (4) above, wherein the adjustment unit urges the user to lower the importance by displaying a message recommending lowering the importance.

[0015] (7) An automatic shift generation device according to (1) or (2) above, further comprising an output unit that outputs the generated shift table.

[0016] (8) A method for automatically generating shift tables, the method comprising: (a) a step of acquiring a plurality of rules related to shifts and the importance of each of the rules; (b) a step of generating a plurality of next-generation shift tables by evolving a plurality of shift tables as a plurality of individuals of the current generation into a plurality of next-generation individuals based on the rules and the importance using a genetic algorithm that evolves a plurality of individuals of the current generation into a plurality of next-generation individuals; (c) a step of evaluating the degree of achievement of the rules for each of the generated shift tables; and (d) a step of identifying rules among the plurality of rules whose degree of achievement should be improved, and adjusting the importance of rules other than the identified rules to be lowered, or prompting a user to lower the importance.

[0017] (9) An automatic shift generation program for causing a computer to execute the processes included in the automatic shift generation method described above in (7). [Effects of the Invention]

[0018] According to the present invention, the automatic shift generation device, automatic shift generation method, and automatic shift generation program adjust the importance of multiple rules to lower those rules excluding those rules whose achievement level should be improved, or prompt the user to lower their importance. This increases the importance of the rules whose achievement level should be improved relative to the rules whose importance has been lowered, improving the achievement level of the rules whose achievement level should be improved. As a result, the overall achievement level of multiple rules improves. This reduces the time and effort required for users to manually revise shift schedules. [Brief explanation of the drawings]

[0019] Advantages and features provided by one or more embodiments of the present invention will be more fully understood from the following detailed description and the accompanying drawings, which are for purposes of illustration only and are not intended to define the limits of the invention. [Figure 1] 1 is a block diagram illustrating a schematic configuration of an automatic shift generation system according to an embodiment of the present invention. [Figure 2] 2 is a block diagram showing a schematic configuration of the information processing terminal shown in FIG. 1. FIG. [Figure 3] 3 is a schematic diagram illustrating a rule reception screen displayed on the operation display unit shown in FIG. 2. FIG. [Figure 4] FIG. 10 is a schematic diagram illustrating a screen for setting the importance of a rule. [Figure 5] FIG. 1 is a block diagram illustrating a schematic configuration of an automatic shift generation device. [Figure 6] 6 is a functional block diagram illustrating the functions of the CPU shown in FIG. 5. [Figure 7] 2 is a block diagram illustrating a schematic configuration of a first server shown in FIG. 1. FIG. [Figure 8] 2 is a block diagram illustrating a schematic configuration of a second server shown in FIG. 1. [Figure 9] 1 is a sequence chart illustrating an example of the operation of an automatic shift generation system in one embodiment. [Figure 10] 10 is a flowchart illustrating the process of performing genetic operations and adjusting the importance of rules, following FIG. 9. [Figure 11] FIG. 10 is a schematic diagram illustrating a screen displaying the degree of achievement of each rule. DETAILED DESCRIPTION OF THE INVENTION

[0020] Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the scope of the present invention is not limited to the disclosed embodiments. In the drawings, the same elements are denoted by the same reference numerals, and duplicate explanations will be omitted. Furthermore, the dimensional proportions in the drawings are exaggerated for the sake of explanation and may differ from the actual proportions.

[0021] (Embodiment) FIG. 1 is a block diagram illustrating the schematic configuration of an automatic shift generation system 10 according to one embodiment of the present invention. The automatic shift generation system 10 includes an information processing terminal 100, an automatic shift generation device 200, a first server 300, and a second server 400. The information processing terminal 100, the automatic shift generation device 200, the first server 300, and the second server 400 are interconnected via a network 500. The automatic shift generation device 200, the first server 300, and the second server 400 may be implemented, for example, as cloud servers. In this case, the automatic shift generation system 10 may be configured, for example, by the information processing terminal 100 installed within a facility such as a nursing home, hospital, or factory, and a cloud server installed outside the facility. Furthermore, when the automatic shift generation device 200, the first server 300, and the second server 400 are implemented as on-premise servers, the automatic shift generation system 10 may be installed within a facility such as a nursing home, hospital, or factory. Alternatively, some or all of the components of the automatic shift generation system 10 may be installed outside a facility (for example, in the headquarters building of a corporation that operates multiple facilities). A corporation includes an organization consisting of multiple members (personnel). Members include all personnel who work in accordance with work shift rules (hereinafter simply referred to as "rules").

[0022] The configuration of the automatic shift generation system 10 and the method for automatically generating shifts using the automatic shift generation system 10 will be described below, taking as an example a case where shifts are generated for care staff at a care facility run by a corporation.

[0023] <Information processing terminal 100> The information processing terminal 100 is a terminal used by a user such as a facility director, manager, or administrator of a nursing care facility, and may be a desktop PC (Personal Computer), a notebook PC, a tablet PC, a smartphone, or the like.

[0024] Fig. 2 is a block diagram illustrating a schematic configuration of the information processing terminal 100 shown in Fig. 1. The information processing terminal 100 has a CPU (Central Processing Unit) 110, a ROM (Read Only Memory) 120, a RAM (Random Access Memory) 130, a storage 140, a communication interface 150, and an operation display unit 160. Each component is connected to each other via a bus so that they can communicate with each other.

[0025] The CPU 110 controls the above components and performs various arithmetic processing in accordance with programs stored in the ROM 120 and storage 140. The ROM 120 stores various programs and various data. The RAM 130 temporarily stores programs and data as a working area.

[0026] Storage 140 is configured with a hard disk drive (HDD), a solid state drive (SDD), etc., and stores various programs including an operating system and various data. For example, an application is installed in storage 140 for receiving input (including instructions, etc.) from a user and transmitting and receiving various information to and from other devices such as automatic shift generation device 200. In addition, an application is installed in storage 140 for outputting (displaying) information on operation display unit 160.

[0027] The communication interface 150 is an interface for communicating with other devices. As the communication interface 150, a wired or wireless communication interface conforming to various standards is used.

[0028] The operation display unit 160 is, for example, a touchscreen display, and displays various information such as the generated shift schedule, the degree of rule fulfillment, and / or the selection rules. Details of the degree of rule fulfillment and the selection rules will be described later. The operation display unit 160 also accepts various inputs from the user. The various inputs include, for example, information input to the rules and automatic shift generation device 200.

[0029] [rule] The term "rules" as used herein may refer primarily to rules and practices regarding work shifts at a facility. Rules may be established for each facility, taking into account factors such as the number of staff required for each care task, laws and regulations such as the Labor Standards Act, staff preferences, and facility practices, and then input to the automatic shift schedule generation system 10. The rules may include, for example, facility rules, staff rules, and surcharge rules. Facility rules may include, for example, the number of staff required for each shift, the number of consecutive work days allowed, the number of consecutive vacation days allowed, and the number of public holidays. Staff rules may include, for example, staff working hours, working conditions, staff compatibility, staff pairings, and the number of shifts worked (see Figure 4). Surcharge rules may include staffing standards (caregiving, nursing staff), a daily life support surcharge, night shift staff allocation surcharge (I) and (II), night shift staff allocation surcharge (III) and (IV), an individual functional training surcharge, a nutritional management enhancement surcharge, and a nursing system surcharge. Staff include full-time and part-time caregivers, nurses, and registered dietitians.

[0030] The rules can be input by the user via, for example, the operation and display unit 160. FIG. 3 is a schematic diagram illustrating an example of a rule reception screen displayed on the operation and display unit 160 shown in FIG. 2. The rule reception screen is displayed on the display of the operation and display unit 160. The operation and display unit 160 receives the rules and the like input by the user on the rule reception screen and transmits them to the CPU 110. The CPU 110 transmits the received rules to the second server 400. In the second server 400, the received rules are stored in the storage 440 (see FIG. 8).

[0031] In the example shown in FIG. 3, the number of staff required for each shift is entered as a rule on the rule reception screen. That is, the rule entered is that night shifts (shift symbol "night") are to be assigned to one staff member belonging to a unit called "Unit B" every day every month. The importance of the night shift assignment is set to "required." "Required" may correspond to, for example, a rule importance of 6 or 7, which will be described later.

[0032] Shift symbols are unique symbols that represent shift assignments in a shift schedule. Examples of shift symbols include "night" (night), "day" (day), "early," "late," "after," "after a night shift," and "public" (public holiday). Instead of the Chinese characters "night," "day," "early," "late," and "after," alphabets, numbers, and other characters may be used as shift symbols.

[0033] A shift schedule (work shift schedule) is a list showing the shift assignments for each employee for each day during a specified period, and is generated by arranging shift symbols based on rules. The specified period is usually 30 days, but is not limited to this. In other words, a shift schedule is a table that lists shift symbols for each employee for a specified period.

[0034] Input information to the automatic shift generation device 200 includes facility information, staff information, and shift information for the nursing care facility. Facility information includes, for example, the facility name, facility number, room configuration, number of residents, number of full-time care staff, number of part-time care staff, number of full-time nursing staff, number of part-time nursing staff, and number of full-time dietitians. In addition to name, staff information also includes, for example, (1) occupation (e.g., care staff, nurse, doctor, nutritionist), (2) full-time / concurrent employment, (3) regular / non-regular employment, (4) qualifications (e.g., caregiver, nurse, doctor), and (5) years of service. Staff information also includes information on the unit in charge. Shift information includes, for example, the number of staff working shifts by working time slot and previously created shift schedules.

[0035] [Rule importance] FIG. 4 is a schematic diagram illustrating a screen for setting the importance of rules (hereinafter simply referred to as "importance"). In the automatic shift generation device 200 of this embodiment, the user can set the importance indicating the relative importance of each rule, for example, via the operation display unit 160. FIG. 4 illustrates an example in which the importance of facility rules, staff rules, and accumulating rules can be set. The set importance is saved in the storage 440 of the second server 400. Note that importance can also be set for rules other than facility rules, staff rules, and accumulating rules.

[0036] In this embodiment, the importance of a rule is expressed by a number ranging from 1 to 10, for example, with the larger the number, the higher the importance. In the example shown in FIG. 4, in the facility rule importance setting, "7" is set for the number of staff required for each shift, and "7" is also set for the number of public holidays. Note that recommended values ​​for the importance of each rule are experimentally or empirically determined in advance and stored in storage 240. The recommended values ​​can be used as default values ​​when the user does not set the importance.

[0037] Although it is possible to set the importance of all rules to 10, due to the nature of nursing care work, nursing shifts are often created based on a large number of complexly intertwined rules. Therefore, for example, if the importance of all rules is set to a high value, such as 10 to 8, and a genetic algorithm is used to generate a shift schedule, the accuracy of the shift schedule relative to the overall rules may not be improved, and may even be reduced. The accuracy of a shift schedule represents the overall extent to which multiple rules that the shift schedule must satisfy are achieved, and can be expressed specifically by the individual achievement levels described below. The inventors conducted experiments in which various importance values ​​were set for multiple rules and a genetic algorithm was used to generate a shift schedule. After verifying the accuracy, they confirmed that the accuracy of the generated shift schedule was improved when the importance of each rule was set to 4 to 7. Therefore, it is recommended that the importance of each rule be set to 4 to 7.

[0038] <Automatic shift generation device 200> Fig. 5 is a block diagram illustrating the schematic configuration of automatic shift generation device 200. Fig. 6 is a functional block diagram illustrating the functions of CPU 210 shown in Fig. 5. Automatic shift generation device 200 has CPU 210, ROM 220, RAM 230, storage 240, and communication interface 250. Each component is connected to each other via a network or a bus so that they can communicate with each other.

[0039] The configurations and basic functions of the CPU 210, ROM 220, RAM 230, storage 240, and communication interface 250 are similar to those of the corresponding elements of the information processing terminal 100, and therefore a duplicated description will be omitted.

[0040] Various computer programs, including an automatic shift generation program for executing various processes by the CPU 210, are installed in the storage 240. The storage 240 also stores input information received from the first server 300, rules received from the second server 400, and the importance of the rules.

[0041] The CPU 210 executes the automatic shift generation program to realize various functions. As shown in Fig. 6, for example, the CPU 210 executes the automatic shift generation program to function as an acquisition unit 211, a generation unit 212, an evaluation unit 213, an adjustment unit 214, and an output unit 215. Details of these functional units will be described later.

[0042] <First Server 300> Fig. 7 is a block diagram illustrating a schematic configuration of the first server 300 shown in Fig. 1. The first server 300 has a CPU 310, a ROM 320, a RAM 330, a storage 340, and a communication interface 350. Each component is connected to each other via a network or a bus so that they can communicate with each other.

[0043] The configurations and basic functions of the CPU 310, ROM 320, RAM 330, storage 340, and communication interface 350 are similar to those of the corresponding elements of the information processing terminal 100, and therefore a duplicated description will be omitted.

[0044] First server 300 functions as a database server, storing and managing facility information, staff information, and shift information for the nursing care facility in storage 340. Storage 340 also stores shift tables generated by automatic shift generation device 200. In response to a shift generation request from information processing terminal 100, first server 300 transmits facility information, staff information, and shift information to automatic shift generation device 200 as input information for automatic shift generation device 200.

[0045] <Second Server 400> Fig. 8 is a block diagram illustrating a schematic configuration of the second server 400 shown in Fig. 1. The second server 400 has a CPU 410, a ROM 420, a RAM 430, a storage 440, and a communication interface 450. Each component is connected to each other via a network or a bus so as to be able to communicate with each other.

[0046] The configurations and basic functions of the CPU 410, ROM 420, RAM 430, storage 440, and communication interface 450 are similar to those of the corresponding elements of the information processing terminal 100, and therefore, redundant explanations will be omitted.

[0047] The second server 400 functions as a database server, storing and managing rules and their importance in storage 440. The second server 400 also saves the achievement level for each individual rule. In response to a shift generation request from the information processing terminal 100, the second server 400 transmits the rules and their importance to the automatic shift generation device 200. Rules in storage 440 can be added or updated by input from the information processing terminal 100, etc.

[0048] <Operation of automatic shift generation system 10> Fig. 9 is a sequence chart illustrating the operation of the automatic shift generation system 10 in this embodiment. Fig. 10 is a flowchart illustrating the process of performing genetic manipulation and adjusting the importance of rules, which follows Fig. 9. Fig. 11 is a schematic diagram illustrating a screen displaying the achievement level of each rule.

[0049] As shown in FIG. 9, for example, a user issues a shift creation instruction via the operation display unit 160. The information processing terminal 100 sends a shift creation request to the automatic shift generation device 200, the first server 300, and the second server 400 in accordance with the user's instructions. Upon receiving the shift creation request, the automatic shift generation device 200 executes the processes of steps S101 to S108, which will be described below. Furthermore, upon receiving the shift creation request, the first server 300 sends input information to the automatic shift generation device 200. As described above, the input information includes facility information, staff information, and shift information. Furthermore, upon receiving the shift creation request, the second server 400 sends rules and the importance of the rules to the automatic shift generation device 200.

[0050] [Acquisition of rules, rule importance, and input information (Step S101)] The acquisition unit 211 acquires the rules, the importance, and the input information. More specifically, the acquisition unit 211 acquires the input information received from the first server 300, and the multiple rules and the importance of each rule received from the second server 400.

[0051] [Generate shift table] In this embodiment, the generation of a shift table includes the following steps: generating an initial population (step S102), calculating the achievement level for each individual (step S103), determining whether the achievement level for each individual satisfies a predetermined standard (step S104), and performing genetic operations (steps S105 to S107). Individuals are shift tables as candidate solutions.

[0052] The generation unit 212 generates individuals. The generation unit 212 generates a plurality of next-generation shift tables by evolving a plurality of shift tables as a plurality of individuals of the current generation into a plurality of next-generation shift tables using a genetic algorithm. The genetic algorithm is an algorithm that evolves a plurality of individuals of the current generation into a plurality of individuals of the next generation. Since the genetic algorithm itself is a known algorithm, an outline of the evolution of individuals by the genetic algorithm will be described below in association with the automatic shift generation method of this embodiment.

[0053] [Generation of individuals (initial population) (step S102)] The generation unit 212 randomly generates an initial population (first generation) consisting of multiple individuals. In this embodiment, the initial population consists of, for example, N individuals. One individual can be, for example, a 30-day shift schedule for two staff members, staff member 1 and staff member 2. Therefore, the number of dimensions n of one individual is 2 × 30 = 60. Shift symbols are randomly allocated in the shift schedule. For example, the five shift symbols that can be assigned are "early," "day," "late," "night," and "public." In other words, the number of types T of shift symbols is five. Note that the number of shift symbols that can be assigned is not limited to the above five, and may be six or more.

[0054] Note that instead of randomly generating the initial population, the initial population may be generated based on a previously generated shift table included in the shift information. For example, the generation unit 212 may generate N variations of a shift table by partially changing a previously generated shift table, and use these variations of the shift table as the initial population.

[0055] [Calculation of individual achievement level (step S103)] The evaluation unit 213 calculates the degree of achievement (evaluation value) for each individual. The degree of achievement is a value indicating to what extent each individual has achieved (satisfied) each rule, and in this embodiment, the closer the value is to 1.0 (100%), the higher the degree to which the rule has been achieved.

[0056] Figure 11 shows an example of the degree of achievement calculated for rules such as the number of employees required for each shift, the number of consecutive work days available, and the number of consecutive vacation days available. For example, the degree of achievement for the number of employees required for each shift is 83.93%, and the degree of achievement for the number of consecutive work days available and the number of consecutive vacation days available is 100%. The degree of achievement for other rules is calculated in a similar manner.

[0057] For example, when three rules, rules A to C, are used to generate a shift table (individual), the weighted achievement degree for each rule is calculated by the following formulas (1) to (3).

[0058] Weighted achievement rate of Rule A a = Weighting coefficient α × Achievement rate of Rule A... (1) Weighted achievement rate of Rule B b = Weighting coefficient β × Achievement rate of Rule B…(2) Weighted achievement rate of rule C c = weight coefficient γ × achievement rate of rule C…(3) The weighting coefficients α, β, and γ are each a value greater than or equal to 0 and less than 1, and can be set so that the sum of the weighting coefficients α, β, and γ is 1. The weighting coefficients α, β, and γ can each be set arbitrarily by the user. The weighting coefficients α, β, and γ can be set, for example, according to the importance of the rule. More specifically, the weighting coefficients α, β, and γ can be set so that the higher the importance, the larger the value. For example, if the importance of rule A > the importance of rule B > the importance of rule C, the weighting coefficients can be set so that α > β > γ.

[0059] The individual achievement level (overall achievement level) is calculated, for example, by the following formula (4).

[0060] Individual achievement = weighted achievement a + weighted achievement b + weighted achievement c... (4) [Determining whether the achievement level of each individual satisfies a predetermined standard (Step S104)] The evaluation unit 213 determines whether the achievement level of each individual satisfies a predetermined criterion as a termination condition for the genetic algorithm. For example, the evaluation unit 213 calculates a representative achievement level based on the achievement level of each individual and determines whether the representative achievement level is equal to or greater than a predetermined first threshold. That is, if the representative achievement level is equal to or greater than the predetermined first threshold, the achievement level of each individual is deemed to satisfy the predetermined criterion, and if the representative achievement level is less than the predetermined first threshold, the achievement level of each individual is deemed not to satisfy the predetermined criterion. The representative achievement level may be, for example, the average, maximum, minimum, or median of the achievement levels of all individuals. The evaluation unit 213 transmits a request for a rule achievement threshold, and upon receiving the request, the second server 400 transmits the first threshold to the evaluation unit 213 as the rule achievement threshold.

[0061] If the achievement level of each individual satisfies a predetermined standard, that is, if the representative achievement level is equal to or greater than the first threshold (step S104: YES), the evaluation unit 213 determines that the individual has converged to a solution that satisfies the termination condition, and terminates the process (END). This stops the evolution of the individual by the genetic algorithm.

[0062] On the other hand, if the achievement level of each individual does not satisfy the predetermined standard, i.e., if the representative achievement level is less than the first threshold (step S104: NO), the evaluation unit 213 proceeds to the process of implementing genetic operations (steps S105 to S107). The generation unit 212 controls the evolution of the individuals to continue using the genetic algorithm until the representative achievement level becomes sufficiently large. In other words, the process of generating individuals continues until the individuals converge to a solution that satisfies the termination condition.

[0063] Alternatively, the evaluation unit 213 may be configured to determine whether the rate of change (rate of increase) ε of representative achievement between generations for individuals of the second generation and beyond is equal to or less than a predetermined second threshold. That is, if the representative achievement is equal to or less than the second threshold, the achievement of each individual is deemed to satisfy the predetermined standard, and if the rate of change ε ​​of representative achievement exceeds the second threshold, the achievement of each individual is deemed to not satisfy the predetermined standard. For example, the rate of change ε ​​of representative achievement between the kth generation and the (k-1)th generation may be defined as (representative achievement of the kth generation - representative achievement of the (k-1)th generation) / representative achievement of the kth generation. The evaluation unit 213 transmits a request for the threshold for rule achievement, and upon receiving the request, the second server 400 transmits the second threshold to the evaluation unit 213 as the threshold for rule achievement.

[0064] If the achievement level of each individual satisfies a predetermined standard, that is, if the change rate ε of the representative achievement level is equal to or less than the second threshold (step S104: YES), the evaluation unit 213 determines that the individual has converged to a solution that satisfies the termination condition, and terminates the process (END). This stops the evolution of the individual by the genetic algorithm.

[0065] On the other hand, if the achievement level of each individual does not satisfy the predetermined standard, that is, if the change rate ε of the representative achievement level exceeds the second threshold (step S104: NO), the evaluation unit 213 proceeds to the process of implementing genetic operations (steps S105 to S107). The evaluation unit 213 controls so that evolution is repeated using the genetic algorithm until the change rate ε of the representative achievement level between generations becomes sufficiently small. In other words, the process of generating individuals continues until the individuals converge to a solution that satisfies the termination condition.

[0066] The termination condition may be a combination of determining the magnitude of the representative achievement level and determining the rate of change ε ​​of the representative achievement level between generations. Furthermore, the termination condition may be configured to limit the number of iterations of evolution by the genetic algorithm to a predetermined number.

[0067] If the achievement level for each individual meets a predetermined standard, the automatic shift generation device 200 sends the generated shift table to the first server 300. The first server 300 saves the received shift table in storage 340 (step S109). The automatic shift generation device 200 also sends the achievement level calculated by the evaluation unit to the second server 400. The second server 400 saves the achievement level in storage 440 (step S110). Furthermore, the output unit 215 outputs (sends) the generated shift table, achievement level, and selection rule to the information processing terminal 100. The operation display unit 160 can display the shift table, achievement level, and / or selection rule (step S111).

[0068] The generation unit 212 performs at least one of the following genetic operations on a plurality of individuals: natural selection, crossover, and mutation. An example of a typical procedure for genetic operations is shown in Fig. 10, but the present invention is not limited to this example.

[0069] 10, as an example, the generation unit 212 may serially perform the genetic operations of natural selection, crossover, and mutation. That is, the generation unit 212 performs natural selection on a plurality of individuals in the current generation, performs crossover on highly evaluated individuals to generate a plurality of new individuals (next generation), and then performs mutation on these new individuals. Specific examples of the genetic operations of natural selection, crossover, and mutation are described below.

[0070] [Implementation of natural selection (Step S105)] The generation unit 212 performs natural selection on a plurality of individuals in the current generation. Natural selection, also called selection, selects individuals whose shift symbol patterns will be passed on to the next generation from the plurality of individuals in the current generation based on the achievement level of each individual in the current generation. That is, through natural selection, the shift symbol patterns of selected individuals from the plurality of individuals in the current generation are transferred to individuals in the next generation. Generally, in natural selection, the shift symbol patterns of highly evaluated individuals are selected so as to be passed on to the next generation. The automatic shift symbol generation device of this embodiment can use methods such as roulette selection, ranking selection, tournament selection, and elite selection as a selection method based on the achievement level. Note that these selection methods are well known, and detailed explanations thereof will be omitted.

[0071] [Performing crossover (step S106)] The generation unit 212 performs crossover on a plurality of individuals that have undergone natural selection. Crossover is a genetic operation that generates new shift symbol patterns in individuals of the next generation by rearranging shift symbols between selected individuals of the current generation with a predetermined crossover probability. The automatic shift generation device of this embodiment can employ one-point, two-point, multi-point crossover, and uniform crossover. Note that crossover methods are well known, so detailed explanations will be omitted.

[0072] [Implementing mutation (step S107)] The generation unit 212 performs mutation on the new individuals obtained by the crossover. Mutation is a genetic operation that changes some shift symbols in the selected shift with a predetermined mutation probability.

[0073] [Adjusting the Importance of Rules (Step S108)] The adjustment unit 214 identifies a rule (hereinafter referred to as a "rule to be improved") whose degree of achievement should be improved (enhanced) from among the multiple rules. For example, the adjustment unit 214 may identify a rule whose degree of achievement does not satisfy a predetermined standard as the rule to be improved. Alternatively, the adjustment unit 214 may identify a rule whose degree of achievement does not satisfy a predetermined standard and whose importance is equal to or greater than a specified value as the rule to be improved. For example, the adjustment unit 214 may identify a rule whose degree of achievement is 0.9 (less than 90%) and whose importance is equal to or greater than a recommended value as the rule to be improved. Alternatively, the adjustment unit 214 may be configured to identify a rule designated by a user as the rule to be improved.

[0074] It may be possible to increase the importance of the rule to be improved in order to improve the degree of achievement, but as mentioned above, setting a high value for the importance may result in a decrease in the accuracy of the shift table for the overall rule.

[0075] Therefore, in this embodiment, the adjustment unit 214 selects rules whose importance is to be reduced from among the multiple rules, and adjusts the selected rules so that the importance is reduced. More specifically, the adjustment unit 214 selects rules from the multiple rules excluding the rule to be improved (hereinafter referred to as "selected rules"), and adjusts the selected rules so that the importance is reduced. For example, the adjustment unit 214 reduces the importance of the selected rules by subtracting a predetermined value from the current importance of the selected rules. For example, if the current importance of the selected rules is 3 and the predetermined value is 1, the adjustment unit 214 subtracts the predetermined value (1) from the current importance (3) to reduce the importance to 3-1=2. As a result, the importance of the rule to be improved is relatively increased compared to the selected rules whose importance has been reduced, and the achievement level of the rule to be improved is improved.

[0076] In addition, instead of adjusting the importance of the selection rule, the adjustment unit 214 may be configured to prompt the user to lower the importance of the selection rule by displaying a message recommending lowering the importance of the selection rule.

[0077] The automatic shift generation device 200, automatic shift generation method, and automatic shift generation program of the present embodiment described above adjust the importance of selected rules, excluding the rule to be improved, among multiple rules, to lower the importance, or prompt the user to lower the importance. This increases the importance of the rule to be improved relative to the selected rule whose importance has been lowered, improving the achievement level of the rule to be improved. As a result, the achievement level of the multiple rules as a whole improves. This reduces the time and effort required for users to manually correct shift schedules.

[0078] The configurations of the automatic shift generation device, automatic shift generation method, and automatic shift generation program described above are the main configurations described in explaining the features of the above-mentioned embodiments, and are not limited to the above-mentioned configurations and can be modified in various ways within the scope of the claims.

[0079] For example, the information processing terminal 100 and the automatic shift generation device 200 may each include components other than those described above, or may not include some of the components described above.

[0080] Furthermore, the information processing terminal 100 and the automatic shift generation device 200 may be configured as separate devices, or may be configured as a single device.

[0081] Furthermore, the functions of each component of the automatic shift generation system 10 may be realized by other components. For example, at least some of the processing described as being executed by the automatic shift generation device 200 may be executed by the information processing terminal 100 or another device. Furthermore, by incorporating the functions of the information processing terminal 100 into the automatic shift generation device 200, the information processing terminal 100 may be omitted.

[0082] Furthermore, the processing units of the flowcharts in the above embodiments are divided according to the main processing content to make each process easier to understand. The method of dividing the processing steps does not limit the present invention. Each process can be divided into more processing steps. One processing step may execute more processes. Furthermore, multiple steps may be executed simultaneously or in combination.

[0083] In addition, in the above embodiment, the automatic shift generation system 10 has been described as having two servers, the first server 300 and the second server 400, but the functions of storing and managing input information and rules may also be consolidated into one server.

[0084] The means and methods for performing various processes in the systems according to the above-described embodiments can be realized by either dedicated hardware circuits or a programmed computer. The programs may be provided, for example, on a computer-readable recording medium such as a flexible disk or CD-ROM, or online via a network such as the Internet. In this case, the programs recorded on the computer-readable recording medium are typically transferred to and stored in a storage unit such as a hard disk. The programs may also be provided as standalone application software or may be incorporated into the software of the device as a function of the system.

[0085] While embodiments of the present invention have been described and illustrated in detail, the disclosed embodiments are made for purposes of illustration and example only, and not limitation, and the scope of the present invention should be construed by the language of the appended claims. [Explanation of symbols]

[0086] 100 information processing terminal, 110 CPUs, 120 ROM, 130 RAM, 140 storage, 150 communication interface, 160 Operation display section, 200 servers, 210 CPUs, 211 Acquisition Department; 212 generation section, 213 Evaluation Department, 214 Adjustment section, 215 output section, 220 ROM, 230 RAM, 240 storage, 250 communication interface, 300 First Server, 310 CPUs, 320 ROM, 330 RAM, 340 storage, 350 communication interface, 400 First Server, 410 CPUs, 420 ROM, 430 RAM, 440 storage, 450 communication interface.

Claims

1. an acquisition unit that acquires a plurality of rules related to shifts and the importance of each of the rules; a generating unit that generates a plurality of next-generation shift tables by evolving a plurality of shift tables as a plurality of current-generation individuals into a plurality of next-generation individuals based on the rule and the importance, using a genetic algorithm that evolves a plurality of current-generation individuals into a plurality of next-generation individuals; an evaluation unit that evaluates the degree of achievement of the rule for each of the generated shift tables; An automatic shift generation device having an adjustment unit that identifies rules among the plurality of rules whose achievement level should be improved, and adjusts rules other than the identified rules to lower their importance, or prompts a user to lower their importance.

2. The automatic shift generation device according to claim 1 , wherein the adjustment unit identifies a rule whose degree of achievement does not satisfy a predetermined standard as a rule whose degree of achievement should be improved.

3. The automatic shift generation device according to claim 1 , wherein the adjustment unit identifies a rule designated by a user as a rule for which the achievement level should be improved.

4. The automatic shift generation device according to claim 1 , wherein the adjustment unit identifies a rule whose achievement level does not satisfy a predetermined standard and whose importance level is equal to or greater than a specified value as a rule whose achievement level should be improved.

5. 5. The automatic shift generation device according to claim 1, wherein the adjustment unit reduces the importance by subtracting a predetermined value from the importance.

6. The automatic shift generation device according to any one of claims 1 to 4, wherein the adjustment unit urges the user to lower the importance by displaying a message recommending lowering the importance.

7. 3. The automatic shift generation device according to claim 1, further comprising an output unit that outputs the generated shift table.

8. (a) obtaining a plurality of rules relating to shifts and a weighting of each of said rules; (b) generating a plurality of next-generation shift tables by evolving a plurality of current-generation individuals into a plurality of next-generation individuals based on the rule and the importance using a genetic algorithm that evolves a plurality of current-generation individuals into a plurality of next-generation individuals; (c) evaluating the degree of fulfillment of the rules for each of the generated shift tables; and (d) identifying a rule among the plurality of rules whose achievement should be improved, and adjusting or prompting a user to lower the importance of rules other than the identified rule.

9. An automatic shift generation program for causing a computer to execute the processes included in the automatic shift generation method according to claim 8.

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