Ship distribution plan creation device, ship distribution plan creation method, and recording medium

Abstract

A server device (2) derives a ship distribution plan for transporting, by a plurality of ships, raw materials from a plurality of loading ports to an unloading port, the server device (2) comprising: an acquisition unit (21) that acquires information relating to a plurality of loading port groups into which the loading ports are grouped; a setting unit (22) that sets an index corresponding to each of the loading port groups and including a parameter pertaining to the ship distribution plan as a variable, with the index indicating the total number of stopping ports for the ships in each loading port group, and when one ship stops at a plurality of loading ports belonging to the same loading port group, the number of stopping ports for said ship being counted as a fewer number than the number of loading ports; and a calculation unit (23) that derives each parameter pertaining to the ship distribution plan such that the value of the objective function, set based on the sum of the terms related to the indices corresponding to the respective loading port groups, decreases.

Description

Vessel routing plan creation device, vessel routing plan creation method, and recording medium

[0001] (Cross-reference to related applications) This application claims the benefit of priority from the specification of Japanese Patent Application No. 2024-052832, filed March 28, 2024, the specification of which is incorporated herein by reference in its entirety. (Technical Field) The present disclosure relates to a vessel routing plan creation device, a vessel routing plan creation method, and a recording medium.

[0002] When transporting raw materials by ship, a ship allocation plan is drawn up from the loading port to the discharging port. However, ship allocation plans tend to become more complex, and various solutions have been proposed.

[0003] For example, Patent Document 1 discloses that an objective function is used to create a blending plan for mixing incoming raw materials at the discharge port, and a shipping plan is created based on the blending plan.

[0004] Patent No. 4669582

[0005] When creating a shipping schedule that takes into account the transportation costs of raw materials, it is conceivable to evaluate the transportation costs based on the number of port calls of a ship and create a shipping schedule that minimizes the number of port calls. However, when multiple ships call at multiple loading ports, depending on the port call patterns of each ship at each loading port, the route distance may become long even if the number of port calls is small, resulting in high transportation costs. Patent Document 1 describes that it is possible to set conditions in advance to eliminate patterns with inappropriate travel distances, but does not disclose specific conditions. A specific method is needed to create a shipping schedule that minimizes transportation costs.

[0006] In view of the above problems, the present disclosure aims to provide a shipping plan creation device, a shipping plan creation method, and a recording medium that can create a shipping plan that reduces transportation costs while limiting the number of port calls.

[0007] In order to solve the above problem, a shipping allocation plan creation device according to one aspect of the present disclosure is a shipping allocation plan creation device that derives a shipping allocation plan for transporting raw materials from multiple loading ports to a discharging port by multiple ships, and includes: an acquisition unit that acquires information about multiple loading port groups into which each of the loading ports is grouped; a setting unit that sets an index that includes parameters related to the shipping allocation plan as variables and corresponds to each of the loading port groups, indicating the total number of port calls of each of the ships for the loading port group, and in the case where one ship calls at multiple loading ports belonging to the same loading port group, the number of port calls of the ship is counted as being less than the number of port calls of the multiple ports; and a calculation unit that derives each of the parameters related to the shipping plan so as to reduce the value of an objective function that is set by the sum of terms related to the index corresponding to each of the loading port groups.

[0008] A shipping plan creation method according to another aspect of the present disclosure is a shipping plan creation device that derives a shipping plan for transporting raw materials from multiple loading ports to a discharging port by multiple ships, and includes: an acquisition unit that acquires information regarding multiple loading port groups into which each of the loading ports is grouped; a setting unit that sets an index that includes parameters related to the shipping plan as variables and corresponds to each of the loading port groups, indicating the total number of port calls of each of the ships for the loading port group, and in the case where one ship calls at multiple loading ports belonging to the same loading port group, the number of port calls of the ship is counted as being less than the number of ports; and a calculation unit that derives each of the parameters related to the shipping plan so as to reduce the value of an objective function that is set by the sum of terms related to the index corresponding to each of the loading port groups.

[0009] A recording medium according to another aspect of the present disclosure is a non-transitory computer-readable recording medium that records a shipping plan creation program, and the shipping plan creation program is a shipping plan creation program that derives a shipping plan for transporting raw materials from multiple loading ports to a discharging port by multiple ships, and causes a computer to function as an acquisition unit that acquires information about multiple loading port groups into which each of the loading ports is grouped, a setting unit that includes parameters related to the shipping plan as variables and sets an index that corresponds to each of the loading port groups and indicates the total number of port calls of each of the ships for the loading port group, and in the case where one ship calls at multiple loading ports belonging to the same loading port group, the number of port calls of the ship is counted as less than the number of port calls of the multiple ports, and a calculation unit that derives each of the parameters related to the shipping plan so as to reduce the value of an objective function that is set by the sum of terms related to the index corresponding to each of the loading port groups.

[0010] The present disclosure may be realized as a semiconductor integrated circuit that implements part or all of a program, as an information processing device, or as a system including an information processing device.

[0011] According to the shipping plan creation device, shipping plan creation method, and recording medium disclosed herein, it is possible to create a shipping plan that reduces transportation costs while limiting the number of port calls.

[0012] 5 is a schematic diagram showing an example of the overall configuration of a shipping allocation plan creation system according to an embodiment of the present disclosure. FIG. 5 is a diagram showing an example of the hardware configuration of a server device. FIG. 6 is a block diagram showing an example of various functions in the server device. FIG. 7 is a diagram showing an overview of the overall process of shipping allocation plans. FIG. 8 is a diagram showing an example of condition information. FIG. 9 is a diagram showing an example of the location of each loading port and each loading port group. FIG. 10 is a diagram showing an example of a direct transportation route and an indirect transportation route. FIG. 11 is a diagram showing an example of a constraint condition. FIG. 12 is a diagram showing an example of a case where a ship calls at each loading port of FIG. 6. FIG. 13 is a diagram showing a reference example of a case where a ship calls at each loading port of FIG. 6. FIG. 14 is a diagram showing the calculation results corresponding to FIG. 5. FIG. 15 is a flowchart showing an example of the flow of a shipping allocation plan creation process.

[0013] First, some aspects of the disclosure will be described.

[0014] A shipping plan creation device according to a first aspect of the present disclosure is a shipping plan creation device that derives a shipping plan for transporting raw materials from multiple loading ports to a discharging port by multiple ships, and includes: an acquisition unit that acquires information regarding multiple loading port groups into which each of the loading ports is grouped; a setting unit that sets an index that includes parameters related to the shipping plan as variables and corresponds to each of the loading port groups, indicating the total number of port calls of each of the ships for the loading port group, and in the case where one ship calls at multiple loading ports belonging to the same loading port group, the number of port calls of the ship is counted as being less than the number of ports; and a calculation unit that derives each of the parameters related to the shipping plan so as to reduce the value of an objective function that is set by the sum of terms related to the index corresponding to each of the loading port groups.

[0015] In the shipping plan creation device according to the second aspect of the present disclosure, which is related to the first aspect, in the indicator, when one ship makes consecutive calls at multiple loading ports belonging to the same loading port group, the number of calls of the ship to the loading port group is counted as a number less than the number of ports.

[0016] In the shipping plan creation device according to the third aspect of the present disclosure, which is related to the first or second aspect, the calculation unit derives a combination of each of the parameters related to the shipping plan that satisfies specified constraints and minimizes the value of the objective function.

[0017] In the shipping plan creation device according to the fourth aspect of the present disclosure, which is related to the first or second aspect, the objective function includes a weighted linear sum obtained by multiplying the indicators corresponding to each of the loading port groups by a coefficient and adding them together.

[0018] In the shipping plan creation device according to the fifth aspect of the present disclosure, which is related to the first or second aspect, the loading ports are grouped so that loading ports that are close to each other belong to the same loading port group.

[0019] In the shipping plan creation device according to the sixth aspect of the present disclosure, which is related to the first or second aspect, the loading ports are grouped so that the loading ports that are close to the discharging port belong to the same loading port group.

[0020] In the shipping plan creation device according to the seventh aspect of the present disclosure, which is related to the fourth aspect, the loading ports are grouped so that the loading ports that are closer to the discharging port belong to the same loading port group, and the coefficient is set to a larger value for the loading port group that is farther away from the discharging port.

[0021] In the shipping plan creation device according to the eighth aspect of the present disclosure, which is related to the first or second aspect, a relay point is provided between the loading port and the discharging port, and the objective function includes, as the variable, a parameter indicating whether or not the ship will pass through the relay point, and the calculation unit performs calculations so that the value of the objective function becomes smaller in both cases where the ship does not pass through the relay point and where the ship passes through the relay point.

[0022] In the shipping plan creation device according to the ninth aspect of the present disclosure, which is related to the first or second aspect, a relay point is provided between the loading port and the discharging port, the objective function is an index whose variables are parameters related to the shipping plan and includes an index indicating the difference between the raw materials to be transported to the discharging port and the raw materials required by the discharging port, and the index includes, as the variables, parameters related to the transportation of the raw materials from the relay point to the discharging port, and the calculation unit performs calculations so that the value of the objective function becomes small when the raw materials are transported from the relay point to the discharging port.

[0023] A shipping plan creation method according to a tenth aspect of the present disclosure is a shipping plan creation method for deriving a shipping plan for transporting raw materials by multiple ships from multiple loading ports to a discharging port, the method comprising the steps of: acquiring information on multiple loading port groups into which the loading ports are grouped; setting an index that includes parameters related to the shipping plan as variables and corresponds to each of the loading port groups, the index indicating the total number of port calls of each of the ships for the loading port group, and in the case where one ship calls at multiple loading ports belonging to the same loading port group, the number of port calls of the ship is counted as being less than the number of port calls; and deriving each of the parameters related to the shipping plan so as to reduce the value of an objective function that is set by the sum of terms related to the index corresponding to each of the loading port groups.

[0024] A recording medium according to an eleventh aspect of the present disclosure is a non-transitory computer-readable recording medium that records a shipping allocation plan creation program, and the shipping allocation plan creation program is a shipping allocation plan creation program that derives a shipping allocation plan for transporting raw materials from multiple loading ports to a discharging port by multiple ships, and causes a computer to function as an acquisition unit that acquires information about multiple loading port groups into which each of the loading ports is grouped, a setting unit that includes parameters related to the shipping plan as variables and sets an index that corresponds to each of the loading port groups and indicates the total number of port calls of each of the ships for the loading port group, and in the case where one ship calls at multiple loading ports belonging to the same loading port group, the number of port calls of the ship is counted as being less than the number of port calls of the multiple ports, and a calculation unit that derives each of the parameters related to the shipping plan so as to reduce the value of an objective function that is set by the sum of terms related to the index corresponding to each of the loading port groups.

[0025] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. To facilitate understanding of the description, the same components and steps in each drawing will be denoted by the same reference numerals as much as possible, and redundant description will be omitted.

[0026] <Overall Configuration> FIG. 1 is a diagram schematically illustrating an example of the configuration of a shipping allocation plan creation system 1 according to this embodiment. The shipping allocation plan creation system 1 is a system that creates a shipping allocation plan for transporting raw materials by ship from a loading port to a discharging port. A loading port is a location (port) where raw materials are loaded onto a ship. For example, the types of raw materials available vary depending on the loading port. A discharging port is a location (port) where raw materials loaded onto a ship and transported are unloaded. In this embodiment, as an example, a case will be described in which multiple loading ports and multiple discharging ports are set. Note that a relay point may be set between the loading port and the discharging port. A relay point is a type of discharging port (or loading port) and is a base where raw materials can be temporarily stored or shipped. There may be one or more relay points. In addition, in this embodiment, a case will be described in which raw materials are transported by multiple ships as an example. The ships include, for example, ocean-going ships and coastal ships.

[0027] Various parameters for creating a shipping plan are referred to as "parameters related to the shipping plan." Parameters related to the shipping plan are various items related to the contents of the shipping plan, and are set in advance, for example, as parameters related to the route and schedule for transporting raw materials by ship from the loading port to the discharging port. For example, parameters related to the shipping plan are set in advance as parameters indicating the amount and date of loading of a specific type of raw material on a ship at the loading port. Note that the parameters related to the shipping plan are not limited to those mentioned above.

[0028] The above-mentioned parameters related to the shipping plan are determined in the shipping plan creation system 1 described later, whereby the shipping plan is created.

[0029] 1, the shipping plan creation system 1 includes a server device 2 and a user terminal 3. The server device 2 and the user terminal 3 are capable of communicating with each other via a network NT.

[0030] The server device 2 is a shipping allocation plan creation device, and is an information processing device (computer) that creates a shipping allocation plan using information input by the user terminal 3. The server device 2 may be a cloud-based or on-premise type. In this embodiment, a case where the server device 2 is a shipping allocation plan creation device will be described as an example, but the shipping allocation plan creation device is not limited to the server device 2.

[0031] The user terminal 3 is a terminal device and an information processing device (computer) used by a user. The user terminal 3 is, for example, a personal computer. The user can input various information using the user terminal 3 and instruct the server device 2 to create a shipping plan.

[0032] <Hardware Configuration> FIG. 2 is a diagram illustrating an example of a hardware configuration of the server device 2. As shown in FIG.

[0033] 2, the server device 2 includes a control device 10, a communication device 11, and a storage device 12. The control device 10 mainly includes a CPU (Central Processing Unit) 13 and a memory 14.

[0034] In the control device 10, the CPU 13 executes predetermined programs stored in the memory 14 or the storage device 12, etc., thereby functioning as various functional components described below. The memory 14 is a computer-readable storage medium and may be composed of at least one of, for example, a random access memory (RAM), a read-only memory (ROM), an erasable program ROM (EPROM), an electrically erasable program ROM (EEPROM), etc. The memory 14 can store various data, such as programs necessary for executing processes in the server device 2.

[0035] The communication device 11 is configured with a communication interface for communicating with an external device, etc. The communication device 11 is capable of communicating with, for example, the user terminal 3.

[0036] The storage device 12 is a non-transitory computer-readable instruction recording medium, and is configured, for example, with a hard disk or a solid state drive. The storage device 12 stores various programs and information required for executing processes in the control device 10, as well as information on the processing results. Other examples of non-transitory computer-readable instruction recording media include portable recording media such as magnetic tape, flexible disks, optical disks, digital versatile disks, Blu-ray disks, magneto-optical disks, memory cards, and USB memory.

[0037] The server device 2 may be composed of a single information processing device or multiple information processing devices. FIG. 2 only shows a portion of the main hardware configuration of the server device 2, and the server device 2 may include other components. For example, the server device 2 may further include an input device (not shown) and a display device (not shown). The input device is an input device (e.g., a keyboard, a mouse, etc.) that accepts input from the outside. The input device accepts user operations and inputs the operations to the server device 2. The display device is a display device (e.g., a display) that outputs data to the outside. The display device outputs characters and images. The server device 2 may have an input device and an output device integrated together (e.g., a touch panel). Like the server device 2, the user terminal 3 includes a control device (CPU and memory), a communication device, a storage device, an operation device, and a display device.

[0038] <Functional Configuration> Figure 3 is a block diagram showing an example of various functions in the server device 2. The shipping plan creation process is executed by the functions of each block. A computer program implementing the functions of at least some of the function blocks shown in Figure 3 may be installed in the storage of one or more computers. The CPUs of one or more computers may load the installed computer program into their main memory and execute it to fulfill the functions of the multiple function blocks shown in Figure 3.

[0039] 3 may be executed by a single computer or may be executed in a distributed manner by multiple computers. When the functions of the functional blocks shown in Fig. 3 are executed in a distributed manner by multiple computers, the multiple computers may transmit and receive data via a communication network including a LAN (Local Area Network), a WAN (Wide Area Network), or the Internet.

[0040] As shown in FIG. 3, the server device 2 has, as its functional configuration, an acquisition unit 21, a setting unit 22, a calculation unit 23, and an output unit 24 as main components.

[0041] In the following description, the function to be calculated by the calculation unit 23 is referred to as the "objective function F." The unknowns in the objective function F are referred to as "variables." In other words, the variables are objects to be derived using the objective function F. The conditions that limit the variables are referred to as "constraints."

[0042] The acquisition unit 21 acquires information set by the user. Vessel routing plans are created by combining various parameters, such as ports and ships, types of raw materials, and shipping routes, making the planning process complex. In other words, creating a vessel routing plan tends to become a large-scale problem. For this reason, as shown in FIG. 4, the overall process P0 for creating a vessel routing plan is divided into a first-half plan P1 and a second-half plan P2.

[0043] The first half plan P1 is a process in which the user determines the outline of the vessel routing plan. That is, in the first half plan P1, the user sets various information as prerequisites related to the vessel routing plan. Note that the various information as prerequisites related to the vessel routing plan may be thought up and set by the user, or may be information determined (calculated) by another device, etc., and set by the user. That is, the various information as prerequisites related to the vessel routing plan is not limited to being thought up and set by the user. The prerequisites related to the vessel routing plan set by the user in the first half plan P1, etc., are referred to as "condition information." The second half plan P2 is a process in which a vessel routing plan is derived by performing calculations using the condition information set in the first half plan P1. That is, the acquisition unit 21 acquires the condition information related to the vessel routing plan set by the user in the first half plan P1. Then, as the second half plan P2, the server device 2 performs calculations using the information acquired by the acquisition unit 21.

[0044] For example, after the user reviews and sets the condition information for the shipping plan, the user inputs the condition information using the user terminal 3. As a result, the acquisition unit 21 of the server device 2 acquires the condition information.

[0045] FIG. 5 is a diagram showing an example of condition information. FIG. 5 shows some of the parameters related to the ship allocation plan. For example, the various items in range 33 in FIG. 5 are parameters related to the ship allocation plan. FIG. 5 shows the following parameters related to the ship allocation plan: ships (ship type), port call order, discharge port, port call date, discharge volume, and procured raw materials. The ships are ships used in the ship allocation plan. In FIG. 5, ships F1 to Fn are shown as the ships. Note that n is an integer and is set based on the number of available ships. The port call order is the order of calls to the discharge ports set in association with the ships. The discharge ports are ports to which the ships deliver the raw materials, and are shown in FIG. 5 as discharge ports A1 to Am. Note that m is an integer and is set based on the number of discharge ports. The port call date is the date on which the ship calls at the discharge port. The discharge volume is the total amount of raw materials delivered to the discharge port. The total amount is the sum of the discharge volumes of each raw material. The procured raw materials are the quantities of each of the multiple types of raw materials delivered from the ship to the discharge port. Figure 5 shows raw materials G1 to Gk as procured raw materials. Note that k is an integer and is set according to the number of types of raw materials.

[0046] The user sets, for example, the information in the range 31 shown in Figure 5 as the condition information. That is, the user sets, for example, the ships to be used in the vessel allocation plan, the port call order, the discharge port, the port call date, and the discharge volume as the information in the range 31. The information in the range 31 (condition information) is an example of a prerequisite for the vessel allocation plan in the first half plan P1, etc. Note that the information in the range 32 in Figure 5 is not set.

[0047] As the condition information, it is preferable that the conditions at the discharging port side (at least one of the information in the range 31) be set, as shown in Fig. 5. Specifically, it is preferable that the condition information include the date when the ship will call at the discharging port (port call date in Fig. 5) and the total amount of raw materials that the ship will supply to the discharging port (discharge amount in Fig. 5). Setting the conditions at the discharging port side as the condition information makes it possible to improve the efficiency of the calculation process described below.

[0048] The condition information also includes information that restricts each parameter related to the shipping schedule. That is, when the user specifies a limit, such as an upper limit, for each parameter, the user sets it as condition information.

[0049] The condition information also includes grouping information for loading ports. The grouping information is information about how to group (categorize) multiple loading ports, or information about the classification results for multiple loading ports based on a predetermined grouping method. Figure 6 is a diagram showing an example of the location of each loading port. As shown in Figure 6, the multiple loading ports are geographically separated. The multiple loading ports are grouped so that loading ports that are close to each other belong to the same loading port group. In other words, the loading port group to which each of the multiple loading ports belongs is set based on a predetermined area. Furthermore, the loading ports are grouped so that loading ports that are close to the discharging port belong to the same loading port group.

[0050] The example in Figure 6 shows loading ports T1 to T8. Each loading port is classified into one of loading port groups Gr0, Gr1, Gr2, and Gr3. Loading port group Gr0 is the group closest to the discharging port. Loading port group Gr1 is the group next closest to the discharging port after loading port group Gr0. Loading port group Gr2 is the group next closest to the discharging port after loading port group Gr1. Loading port group Gr3 is the group next closest to the discharging port after Gr2. Loading port group Gr3 is the group farthest from the discharging port. Loading ports T1 and T2 belong to loading port group Gr0. Loading ports T3 and T4 belong to loading port group Gr1. Loading ports T5 and T6 belong to loading port group Gr2. Loading points T7 and T8 belong to loading point group Gr3. In this way, loading points T1 to T8 are set so that loading points that are close to each other and that are close to the discharging point belong to the same loading point group.

[0051] The user sets which loading port belongs to which loading port group. Then, the acquisition unit 21 acquires grouping information that associates each loading port with the loading port group to which it belongs. Note that the user can change which loading port group each of multiple loading ports belongs to as appropriate. For example, the user may change the loading port group to which each loading port belongs by changing the area that was previously set.

[0052] 3, the acquisition unit 21 acquires the condition information set by the user as the first half plan P1 in the shipping plan. The condition information acquired by the acquisition unit 21 is output to the setting unit 22.

[0053] The setting unit 22 is a functional unit that sets the objective function F based on the condition information. For this purpose, the setting unit 22 includes a variable setting unit 25, a constraint setting unit 26, and an objective function setting unit 27.

[0054] The variable setting unit 25 sets the variables of the objective function F. Specifically, the variable setting unit 25 sets the information obtained from the condition information for each parameter related to the shipping plan, and sets the variables in the objective function F.

[0055] Specifically, the variable setting unit 25 defines the parameters related to the shipping plan, for which information is obtained from the condition information, as "set parameters."Then, the variable setting unit 25 associates the set parameters with the values ​​obtained from the condition information.In this way, the values ​​of the set parameters, which are part of the parameters related to the shipping plan, are determined.

[0056] The variable setting unit 25 then sets, among the parameters related to the shipping plan, parameters corresponding to information that cannot be obtained from the condition information as “unset parameters.” Unset parameters are parameters whose values ​​are unknown.

[0057] The variable setting unit 25 sets the unset parameters as variables of an objective function F, which will be described later.

[0058] 5, the variable setting unit 25 sets the condition information acquired by the acquisition unit 21 as set parameters in a range 31. In contrast, the various parameters shown in a range 32 are parameters for which information was not obtained in the condition information. Therefore, the variable setting unit 25 sets each parameter in the range 32 as an unset parameter.

[0059] In addition, when a relay point is set between the loading port and the discharging port, it is preferable that the parameters related to the shipping plan include a parameter indicating whether or not the shipping route will pass through the relay point. The parameter indicating whether or not the shipping route will pass through the relay point is referred to as a "relay parameter." The relay parameter is set, for example, for each ship. In addition, when multiple ships are used in the shipping plan, the relay parameter may be associated with all ships or with some of the ships. FIG. 7 is a diagram showing loading ports, relay points, and discharging ports. FIG. 7 shows loading port T1 as an example of a loading port and discharging port A3 as an example of a discharging port. FIG. 7 also shows relay point M1 as an example of a relay point. FIG. 7 also shows ship F1 as an example of an oceangoing vessel and ship F5 as an example of a coastal vessel. A route for transporting raw materials directly from loading port T1 to discharging port A3 is referred to as a "direct transport route L1." In the direct transport route L1, for example, ship F1 transports raw materials directly from loading port T1 to discharging port A3. The route for transporting raw materials from the loading port T1 to the discharging port A3 via the relay point M1 is referred to as the "indirect transport route L2." In the indirect transport route L2, for example, the ship F1 transports the raw materials from the loading port T1 to the relay point M1, and the ship F5 transports the raw materials from the relay point M1 to the discharging port A3. In this way, the ship F1 can take two types of routes, and the route to be taken is indicated by the relay parameter. Specifically, if the relay parameter indicates that the relay point M1 is passed through, the route is the indirect transport route L2, and if the relay parameter indicates that the relay point M1 is not passed through, the route is the direct transport route L1. If the relay parameter is specified by the condition information set by the user, it becomes a set parameter, and if the relay parameter is not specified by the condition information set by the user, it becomes an unset parameter.

[0060] Furthermore, it is preferable that the parameters related to the vessel allocation plan include parameters related to the transportation of raw materials from the relay point to the discharging point. The parameters related to the transportation of raw materials from the relay point to the discharging point are referred to as "transportation parameters between relay and discharging point." The transportation parameters between relay and discharging point include, for example, parameters indicating the transportation of raw materials from the relay point to the discharging point by coastal vessel, parameters indicating the total amount of raw materials to be transported from the relay point to the discharging point, and parameters indicating the amount of each type of raw material to be transported from the relay point to the discharging point. The transportation parameters between relay and discharging point are set parameters if specified by the condition information set by the user, and are unset parameters if not specified by the condition information set by the user. Here, FIG. 7 illustrates an example of the transportation of raw materials from relay point M1 to discharging point A3 by ship F5. In this case, the relay-discharge port transportation parameters include, for example, at least one of a parameter indicating that ship F5 transports raw materials from relay point M1 to discharge port A3, a parameter indicating the total amount of raw materials that ship F5 transports from relay point M1 to discharge port A3, and a parameter indicating the amount of each type of raw material that ship F5 transports from relay point M1 to discharge port A3.

[0061] In this way, each parameter related to the shipping schedule is set as a set parameter or an unset parameter. The unset parameter is then set as a variable of the objective function F.

[0062] The constraint setting unit 26 sets constraint conditions. The constraint conditions are conditions used when finding solutions for the variables set by the variable setting unit 25 using an objective function F, which will be described later. In other words, the solutions for the variables are solutions that satisfy the constraint conditions. The constraint setting unit 26 sets the constraint conditions based on condition information set by the user.

[0063] FIG. 8 is a diagram showing an example of constraints. FIG. 8 lists constraints S1 to S18. Constraint S1 is a constraint on the total amount loaded onto an ocean-going vessel. Constraint S2 is a constraint on the draft of the discharging port. Constraint S3 is a constraint on the lower limit of the amount of raw material loaded at the loading port. Constraint S4 is a constraint on the lower limit of the amount of raw material unloaded at the discharging port. Constraint S5 is a constraint on the lower limit of the amount of raw material loaded. Constraint S6 is a constraint on the upper limit of the number of types of raw material that can be loaded onto one ocean-going vessel. Constraint S7 is a constraint on the upper and lower limits of the difference between the amount unloaded at each discharging port and the required amount. Constraint S8 is a constraint related to the equalization of the amount unloaded. Constraint S9 is a constraint on the total amount loaded onto a coastal vessel. Constraint S10 is a constraint on the upper limit of the amount of raw material delivered to each discharging port. Constraint S11 is a constraint on the upper limit of the amount of raw material group delivered to each discharging port. Constraint S12 is a constraint condition for the initial value of raw material group tank inventory at the relay point. Constraint S13 is a constraint condition for the upper and lower limits of raw material group tank inventory at the relay point. Constraint S14 is a constraint condition for the lower limit of the monthly raw material matching rate. Constraint S15 is a constraint condition for the lower limit of the monthly raw material group matching rate. Constraint S16 is a constraint condition for the upper limit of the number of loading port calls for each ocean-going ship. Constraint S17 is a constraint condition for the lower limit of the amount of raw material group loading onto a domestic ship.

[0064] The constraints in FIG. 8 are merely examples, and constraints other than those in FIG. 8 may be set.

[0065] Returning to FIG. 3, in this manner, constraint conditions for the objective function F, which will be described later, are set.

[0066] The objective function setting unit 27 sets an objective function F. In this embodiment, the objective function F is a function to be minimized in an optimization problem related to the creation of a shipping schedule. The objective function F is set in advance as a function including each parameter related to the shipping schedule. Therefore, for the parameters set in the variable setting unit 25 as set parameters, the objective function setting unit 27 inputs values ​​corresponding to the parameters into the preset objective function F. The objective function setting unit 27 sets the parameters set in the variable setting unit 25 as set parameters as fixed values. The objective function setting unit 27 does not input values ​​corresponding to the parameters set in the variable setting unit 25 as unset parameters. The objective function setting unit 27 sets the parameters set in the variable setting unit 25 as unset parameters as variables. In this way, the variable setting unit 25 sets the objective function F corresponding to the condition information set by the user.

[0067] In this embodiment, the objective function F is expressed by the following equation (1).

[0068]

[0069] In formula (1), the term w1·obj1+FG is an index indicating the cost of transporting raw materials. In contrast, the term w2·obj2+w3·obj3+w4·obj4 is an index indicating the difference between the raw materials scheduled to be transported to the discharging port and the raw materials required by the discharging port. In other words, this term is an index indicating the degree of deviation between the planned and ideal raw materials for transportation. The objective function F is set as the sum of a term related to cost and a term related to the difference between the planned and ideal raw material transportation. For example, when trying to reduce costs, the difference between the planned and ideal raw material transportation tends to increase, and when trying to reduce the difference between the planned and ideal raw material transportation, costs tend to increase. Therefore, by setting the objective function F as the sum of each term, it is possible to evaluate the objective function F while balancing the two.

[0070] Specifically, in equation (1), w1 represents a coefficient (constant) by which obj1 is multiplied. obj1 is a function that includes unset parameters as variables. obj1 is an index that indicates the cost of transportation. Specifically, obj1 is an index that indicates the total number of port calls of each ship at each of multiple loading ports. That is, the number of port calls at each loading port is calculated for each ship, and the total value of each port call becomes obj1. The total value is, for example, the total value for a month (within a specified period). Since the cost of transportation increases as the number of port calls increases, obj1 uses the number of port calls as an index that indicates the cost of transportation. If the number of port calls is small (cost is low), obj1 will have a small value. Note that obj1 is not limited to a specific function as long as it includes unset parameters as variables and an index (value) corresponding to the state of the unset parameters is obtained.

[0071] FG is an index showing the cost of transportation. Specifically, FG is an index showing the number of port calls of a ship for a loading port group. When the loading port groups are divided into four groups, Gr0, Gr1, Gr2, and Gr3, as shown in FIG. 6, FG is expressed as the following formula (2):

[0072]

[0073] In equation (2), wG0 is a coefficient (constant) multiplied by objG0, wG1 is a coefficient (constant) multiplied by objG1, wG2 is a coefficient (constant) multiplied by objG2, and wG3 is a coefficient (constant) multiplied by objG3.

[0074] Each of objG0, objG1, objG2, and objG3 is a function that includes unset parameters as variables, and is an index corresponding to each loading port group. Note that while obj1 shows an index using the number of ship calls at each loading port, the number of port calls used in objG0, objG1, objG2, and objG3 is counted differently from the number of port calls in obj1. The number of port calls used in objG0, objG1, objG2, and objG3 is referred to as the "number of port calls for a loading port group."

[0075] Specifically, objG0 is an index showing the total number of port calls made by each ship for loading port group Gr0. objG1 is an index showing the total number of port calls made by each ship for loading port group Gr1. objG2 is an index showing the total number of port calls made by each ship for loading port group Gr2. objG3 is an index showing the total number of port calls made by each ship for loading port group Gr3.

[0076] FIG. 9 is a diagram showing an example of a case where a ship calls at each loading port group in FIG. 6 . FIG. 9 illustrates a case where two ships call at each loading port according to a certain shipping plan. The two ships are ships F1 and F2. As shown in FIG. 9 , ship F1 calls at loading port T2 in loading port group Gr0 and then calls at loading port T1 in loading port group Gr0. In this case, the number of port calls for ship F1 in loading port group Gr0 is counted as 1. In other words, when a ship calls at multiple loading ports belonging to the same loading port group, the number of port calls for the ship in that loading port group is counted as fewer than the number of ports. In this embodiment, as an example, when a ship calls at multiple loading ports belonging to the same loading port group, the number of port calls for the ship in that loading port group is counted as 1. Therefore, even if the ship calls at two or more loading ports belonging to the same loading port group, the number of port calls is counted as 1. When the number of port calls to a loading port group is counted in this way, the number of port calls of ship F1 to loading port group Gr0 is 1, not 2. Note that the example in Figure 9 illustrates a case where ship F1 calls at two (multiple) ports, loading port T1 and loading port T2, in loading port group Gr0, and in this case, the number of port calls of ship F1 to loading port group Gr0 is 1, not 2. On the other hand, if ship F1 calls at only one (single) port, loading port T1, in loading port group Gr0, the number of port calls of ship F1 to loading port group Gr0 is 1.

[0077] It is preferable that the counting for each of objG0, objG1, objG2, and objG3 does not depend on the order of port calls at each loading port in each loading port group. In other words, regardless of the order of port calls at each loading port group, if one ship calls at multiple loading ports belonging to the same loading port group, it is preferable to count the number of port calls for that ship for that loading port group as 1. For example, if ship F1 calls at loading port T2 (loading port group Gr0), loading port T8 (loading port group Gr3), and loading port T1 (loading port group Gr0) in that order, the number of port calls for ship F1 for loading port group Gr0 is counted as 1 (the number of port calls for ship F1 for loading port group Gr3 is 1). In this way, it is preferable that the number of port calls for each ship for a loading port group does not take into account the order of port calls. It is also possible to take into account the order of port calls. For example, when a ship successively calls at multiple loading ports belonging to the same loading port group, the number of port calls of the ship in the loading port group may be counted as a number that is less than the number of ports. In other words, when a ship successively calls at multiple loading ports in the same loading port group, the number of port calls may be counted as a number that is less than the number of consecutive loading ports.

[0078] In contrast, ship F2 does not call at any loading ports belonging to loading port group Gr0, so the number of port calls of ship F2 in loading port group Gr0 is zero.

[0079] That is, the number of port calls of ship F1 in loading port group Gr0 is 1, the number of port calls of ship F2 in loading port group Gr0 is 0, and objG0, which is the total number of port calls of each ship in loading port group Gr0, is 1.

[0080] Similarly, the number of port calls of ship F1 in loading port group Gr1 is 0, and the number of port calls of ship F2 in loading port group Gr1 is 0, so objG1, which is the total number of port calls of each ship in loading port group Gr1, is 0.

[0081] Similarly, the number of port calls of ship F1 to loading port group Gr2 is 0, and the number of port calls of ship F2 to loading port group Gr2 is 0, so objG2, which is the total number of port calls of each ship to loading port group Gr2, is 0.

[0082] Furthermore, the number of port calls of ship F1 in loading port group Gr3 is 0. Ship F2 then calls at loading port T8 in loading port group Gr3, and then at loading port T7 in loading port group Gr3. Therefore, the number of port calls of ship F2 in loading port group Gr3 is 1. objG3, which is the total number of port calls of each ship in loading port group Gr3, is 1.

[0083] In the example of FIG. 9, objG0=1, objG1=0, objG2=0, and objG3=1.

[0084] 9, objG0, objG1, objG2, and objG3 are indices calculated as described above. Each of objG0, objG1, objG2, and objG3 is a function that includes unset parameters as variables, and each is an index (value) that corresponds to the state of the unset parameters.

[0085] As shown in equation (2), objG0, objG1, objG2, and objG3 are multiplied by the coefficients of wG0, wG1, wG2, and wG3, respectively, to produce terms related to the indicators corresponding to the loading area groups. These terms are then summed and included in the objective function F as a weighted linear sum.

[0086] As described above, loading port group Gr0, loading port group Gr1, loading port group Gr2, and loading port group Gr3 are set according to the distance from the discharging port. For this reason, it is preferable to set the coefficients wG0, wG1, wG2, and wG3 to larger values ​​for loading port groups that are farther away from the discharging port. In other words, wG1 is set to a value greater than wG0, wG2 is set to a value greater than wG1, and wG3 is set to a value greater than wG2 (wG0<wG1<wG2<wG3). This allows weighting according to the distance from the discharging port.

[0087] Returning to equation (1), w2 denotes a coefficient (constant) by which obj2 is multiplied. obj2 is a function that includes unset parameters as variables. obj2 is an index that indicates the total value of the difference between the amount of raw material scheduled to be transported to the discharging port and the amount of raw material required by the discharging port, calculated for each type of raw material. The total value is, for example, the total value for a month (within a specified period). That is, obj2 is calculated by calculating the difference between the amount of raw material scheduled to be transported to the discharging port and the amount of raw material required by the discharging port for each type of raw material, and the sum of the calculated differences is obj2. Note that obj2 is an index that affects the raw material deviation rate. The larger the difference between the planned and ideal (the greater the degree of deviation), the larger the value of obj2. Note that the deviation rate and the match rate are mutually exclusive, so Obj2 is also an index that affects the raw material match rate. Note that obj2 includes unset parameters as variables, and the specific function is not limited as long as an index (value) corresponding to the state of the unset parameters can be obtained.

[0088] w3 indicates a coefficient (constant) by which obj3 is multiplied. obj3 is a function that includes unspecified parameters as variables. obj3 is an index that indicates the total difference between the amount of raw materials scheduled to be transported to the discharging port and the amount of raw materials required by the discharging port, calculated for each group. The total value is, for example, the total value for a month (within a specified period). A group is a group of raw materials (types) with similar properties. In other words, the difference between the total amount of multiple raw materials in the same group scheduled to be transported to the discharging port and the total amount of multiple raw materials in the same group required by the discharging port is calculated for each group, and these differences are summed to calculate obj3. Note that obj3 is an index that affects the raw material group deviation rate. The larger the difference between the planned and ideal (the greater the degree of deviation), the larger the value of obj3. Note that the deviation rate and the agreement rate are mutually exclusive, so obj3 is also an index that affects the raw material group agreement rate. Note that obj3 is not limited to a specific function as long as it includes unset parameters as variables and can obtain indices (values) corresponding to the states of the unset parameters.

[0089] w4 indicates a coefficient (constant) by which obj4 is multiplied. obj4 is a function that includes unspecified parameters as variables. obj4 is an index that indicates the difference between the weighted average density of each raw material scheduled to be transported to the discharging port and the weighted average density of each raw material requested by the discharging port. This difference is calculated, for example, as a monthly (predetermined period) total. Note that the density of each raw material is set for each type. A weighted average is calculated for the raw material density, using the quantity of each raw material as a weight. That is, a weighted average is calculated based on the quantity and density of each raw material scheduled to be transported to the discharging port, and a weighted average is calculated based on the quantity and density of each raw material requested by the discharging port. The difference between the calculated weighted averages is obj4. If the difference between the scheduled weighted average and the ideal weighted average is large (the degree of deviation is large), obj4 will have a large value. Note that obj4 includes unset parameters as variables, and as long as an index (value) corresponding to the state of the unset parameters can be obtained, the specific function is not limited.

[0090] Although the example has been given in which three indices, obj2, obj3, and obj4, are used in equation (1) as indices showing the difference between the planned and ideal amounts of raw materials for transportation, at least one of them may be used. Furthermore, in this embodiment, the case has been described in which the indices obj1, obj2, obj3, and obj4 are used as shown in equation (1), but other indices may be included in the objective function F. For example, obj5, obj6, etc. may be set as other indices and included in the objective function F.

[0091] In this embodiment, each of the indexes obj1, obj2, obj3, obj4, objG0, objG1, objG2, and objG3 is defined as a function that includes unset parameters as variables, and therefore the objective function F is a function that includes unset parameters as variables. Note that the unset parameters included in each of the indexes obj1, obj2, obj3, obj4, objG0, objG1, objG2, and objG3 may be the same or different.

[0092] In this way, the objective function F is set. In other words, the objective function F represents the objectives related to the vessel allocation plan.

[0093] Returning to FIG. 3 , the calculation unit 23 derives a combination of parameters related to the shipping plan so as to reduce the value of the objective function F. The calculation unit 23 derives values ​​(solutions) of unset parameters included as variables in the objective function F so as to reduce the value of the objective function F. Specifically, the calculation unit 23 derives a solution in which the value of the objective function F is minimum among solutions of unset parameters that satisfy the constraint conditions set by the constraint setting unit 26. In this way, the calculation unit 23 uses the objective function F to search for and derive an optimal solution among solutions of unset parameters.

[0094] In this way, the calculation unit 23 derives an optimal solution for unset parameters by applying a mathematical optimization method or a metaheuristic method with the objective function F as the minimization target.

[0095] In addition, by searching for a solution that reduces the value of the objective function F as shown in equation (1), a solution for the unset parameters is derived so that the cost of transporting raw materials is low and the difference between the raw materials to be transported and the ideal is small.

[0096] Furthermore, the objective function F includes an index FG that is the sum of the number of port calls of each ship for each loading port group, and a solution for the unset parameters is derived so that FG becomes a small value. In this case, a solution for the unset parameters is searched for so that each of objG0, objG1, objG2, and objG3, which are the indexes included in FG and correspond to each of the loading port groups, becomes small.

[0097] FIG. 10 is a diagram showing an example of a ship route pattern when loading ports are not grouped, as a reference example. Similar to FIG. 9 , FIG. 10 illustrates a case where two ships, ships F1 and F2, call at a loading port. Also, similar to FIG. 9 , FIG. 10 illustrates a case where ships F1 and F2 call at loading ports T1, T2, T7, and T8. When loading ports are not grouped, a possible route pattern is shown in FIG. 10 , in which ship F1 calls at loading port T2 and then at loading port T7, and ship F2 calls at loading port T1 and then at loading port T8. In both FIG. 9 and FIG. 10 , the total number of port calls is four. However, when loading ports are not grouped as shown in FIG. 10 , the total distance of the routes of ships F1 and F2 is longer than the total distance of the routes of ships F1 and F2 in FIG. 9 . That is, the reference example of Figure 10 is an inefficient vessel allocation plan compared to Figure 9. For example, if the number of port calls is counted in the example of Figure 10 in the same way as the example of Figure 9, objG0 = 2 (ship F1 is 1, ship F2 is 1), objG1 = 0, objG2 = 0, objG3 = 2 (ship F1 is 1, ship F2 is 1). That is, even if the total number of port calls scheduled at the loading port is the same in the example of Figure 9 and the example of Figure 10, a difference will occur in the value of the sum of the number of port calls for the loading port group (the sum of objG0, objG1, objG2, and objG3).

[0098] Here, the objective function F expressed by Equation (1) is configured to include FG expressed by Equation (2). Therefore, when the calculation unit 23 derives a solution for the unset parameters so that the objective function F has a small value, FG will affect the solution for the unset parameters. Therefore, the calculation unit 23 searches for a solution for the unset parameters so that each of the indicators objG0, objG1, objG2, and objG3 is small. This means that the calculation unit 23 searches for and derives a solution for the unset parameters so that one ship calls at many loading ports in the same loading port group. In other words, the calculation unit 23 derives the unset parameters so that the total distance of the routes of ships F1 and F2 is shortened and costs are reduced. Therefore, the calculation unit 23 can be expected to determine that the route pattern shown in FIG. 9 is superior to the route pattern shown in FIG. 10.

[0099] Furthermore, if the coefficients (wG0, wG1, wG2, wG3) in equation (2) are set to larger values ​​for loading port groups farther from the discharging port (wG0 < wG1 < wG2 < wG3), FG expressed in equation (2) will be more susceptible to the influence of the "wG3 · objG3 term" than the "wG0 · objG0 term." As a result, the calculation unit 23 searches for a solution for the unset parameters so that the number of port calls for a loading port group farther from the discharging port is reduced in order to reduce the value of FG. This means that the calculation unit 23 derives a solution for the unset parameters so that ships preferentially call at loading ports in loading port groups closer to the discharging port. In other words, the calculation unit 23 derives a solution for the unset parameters so that the total distance of the routes of ships F1 and F2 is shortened and costs are reduced. Therefore, it is more likely that the calculation unit 23 will determine that the route pattern shown in FIG. 9 is superior to the route pattern shown in FIG.

[0100] In addition, when the objective function F includes a relay parameter as a variable, a solution search is performed taking into consideration both a direct transportation route L1 in which the ship does not pass through a relay point, and an indirect transportation route L2 in which the ship passes through a relay point.

[0101] Furthermore, when the objective function F includes the transport parameters between the relay point and the discharge point as variables, a solution search is performed taking into account the transport of raw materials from the relay point to the discharge point.

[0102] As described above, an optimal solution for the unset parameters is derived using the objective function F. By setting the unset parameters, the values ​​of the parameters related to the vessel routing plan are determined, and the vessel routing plan is thus created.

[0103] Returning to Fig. 3, the output unit 24 outputs the calculation results obtained by the calculation unit 23. For example, the output unit 24 outputs the optimal solution for the unset parameters as the calculation results to the user terminal 3. In this way, the derived shipping plan is provided to the user.

[0104] Fig. 11 is a diagram showing an example of the result of deriving a shipping allocation plan corresponding to Fig. 5. Each parameter in the range 32 that was not set in Fig. 5 is derived by the objective function F, and a value is set.

[0105] The server device 2 executes the various processes as described above to derive an optimal solution for the vessel routing plan, thereby creating an optimal vessel routing plan.

[0106] <Processing Flow> Figure 12 is a flowchart showing an example of the flow of the shipping plan creation process according to this embodiment. Each of the following steps is started when, for example, a user sets condition information related to the shipping plan as the first half plan P1 and issues an instruction to start the shipping plan creation process. Note that the order and content of each of the following steps can be changed as appropriate.

[0107] (Step SP10) The acquisition unit 21 acquires the condition information, and the process then proceeds to step SP11.

[0108] (Step SP11) The variable setting unit 25 sets variables of the objective function F. Specifically, of the parameters related to the shipping plan, the variable setting unit 25 sets parameters for which information has been obtained from the condition information as set parameters, and sets parameters corresponding to information not obtained from the condition information as unset parameters. Then, the variable setting unit 25 sets the unset parameters as variables of the objective function F. Then, the processing proceeds to step SP12.

[0109] (Step SP12) The constraint setting unit 26 sets constraint conditions based on the condition information, and then the process proceeds to step SP13.

[0110] (Step SP13) The objective function setting unit 27 sets the objective function F based on the set parameters and unset parameters set by the variable setting unit 25. Then, the process proceeds to step SP14.

[0111] (Step SP14) The calculation unit 23 derives unset parameters included as variables in the objective function F so as to reduce the value of the objective function F. Then, the processing proceeds to step SP15.

[0112] (Step SP15) The output unit 24 outputs the optimal solution for the unset parameters as the calculation result to the user terminal 3.

[0113] According to the above flow, a shipping plan is created and provided to the user.

[0114] <Effects> As described above, the shipping allocation plan creation device (server device 2) according to this embodiment is a shipping allocation plan creation device that derives a shipping allocation plan for transporting raw materials from multiple loading ports to a discharging port by multiple ships, and is equipped with an acquisition unit 21 that acquires information about multiple loading port groups into which each loading port is grouped, a setting unit 22 that includes parameters related to the shipping plan as variables and sets an index that corresponds to each loading port group and indicates the total number of port calls of each ship for the loading port group, and in the case where one ship calls at multiple loading ports belonging to the same loading port group, the number of port calls of the ship is counted as being less than the number of port calls, and a calculation unit 23 that derives each parameter related to the shipping plan so as to reduce the value of the objective function F, which is set by the sum of terms related to the indexes corresponding to each loading port group.

[0115] With this configuration, parameters related to the shipping plan are derived so that one ship calls at many ports in the same loading port group. By performing calculations so that one ship calls at many ports in the same loading port group, it becomes possible to perform calculations so that the total distance of the route is shortened. This makes it possible to efficiently create shipping plans that reduce transportation costs while limiting the number of port calls.

[0116] In addition, in the index, if a ship makes consecutive calls at multiple loading ports belonging to the same loading port group, the number of calls made by that ship to the loading port group will be counted as fewer than the number of ports.

[0117] This configuration allows calculations to be performed so that a single ship calls at many consecutive ports in the same loading port group, making it possible to create a shipping schedule that effectively reduces transportation costs.

[0118] Furthermore, in the vessel routing plan creation device, the calculation unit 23 derives a combination of parameters related to the vessel routing plan that satisfies predetermined constraints and minimizes the value of the objective function F.

[0119] This configuration makes it possible to efficiently create a shipping plan that reduces transportation costs while satisfying constraints.

[0120] Furthermore, in the vessel allocation plan creation device, the objective function F includes a weighted linear sum obtained by multiplying the indexes corresponding to each loading port group by a coefficient and adding the resulting coefficients.

[0121] According to this configuration, by forming the indexes corresponding to each loading location group into a weighted linear sum, each index can be reflected in the objective function F in parallel.

[0122] In addition, in the shipping plan creation device, loading ports are grouped so that loading ports that are close to each other belong to the same loading port group.

[0123] With this configuration, the parameters related to the shipping plan are derived so that a single ship will call at many nearby loading ports that belong to the same loading port group. In other words, it is possible to create a shipping plan that effectively reduces transportation costs.

[0124] In addition, in the shipping plan creation device, loading ports are grouped so that loading ports that are close to the discharging port belong to the same loading port group.

[0125] With this configuration, the parameters related to the ship allocation plan are derived so that a single ship will call at many loading ports that belong to the same loading port group and are close to the discharge port. In other words, it is possible to create a ship allocation plan that effectively reduces transportation costs.

[0126] In addition, in the shipping plan creation device, loading ports are grouped so that loading ports that are close to the discharging port belong to the same loading port group, and the coefficient is set to a larger value for loading port groups that are farther away from the discharging port.

[0127] With this configuration, the coefficient is set to a larger value for loading port groups that are farther away from the discharging port, so that loading ports in loading port groups that are closer to the discharging port are preferentially selected. This makes it possible to create a shipping schedule that reduces transportation costs.

[0128] In addition, in the shipping plan creation device, relay points are provided between the loading port and the discharging port, and the objective function F includes, as a variable, a parameter indicating whether or not a ship will pass through the relay point, and the calculation unit 23 performs calculations so that the value of the objective function F becomes small in both the case where the ship does not pass through the relay point and the case where the ship passes through the relay point.

[0129] This configuration allows a vessel allocation plan to be created by evaluating both cases where the route does not pass through a relay point and cases where the route does pass through a relay point. In other words, a vessel allocation plan can be created by taking into account various route patterns.

[0130] In addition, in the shipping plan creation device, relay points are set up between the loading port and the discharging port, and the objective function F is an index whose variables are parameters related to the shipping plan, and includes an index that indicates the difference between the raw materials scheduled to be transported to the discharging port and the raw materials required by the discharging port, and the index includes, as variables, parameters related to the transportation of raw materials from the relay points to the discharging port, and the calculation unit 23 performs calculations so that the value of the objective function F becomes small when raw materials are transported from the relay points to the discharging port.

[0131] This configuration allows for the creation of a shipping plan that takes into account the case where raw materials are transported from a relay point to a discharge port. In other words, raw materials can be transported not only from a discharge port but also from a relay point, making it possible to create a shipping plan that more flexibly responds to the requirements of the discharge port.

[0132] <Modifications> The present disclosure is not limited to the above-described embodiments. In other words, variations of the above-described embodiments to which a person skilled in the art has made appropriate design modifications are also included within the scope of the present disclosure as long as they include the features of the present disclosure. Furthermore, the elements of the above-described embodiments and the modifications described below can be combined to the extent technically possible, and such combinations are also included within the scope of the present disclosure as long as they include the features of the present disclosure.

[0133] For example, in the above embodiment, the server device 2 has each function, but each function may be provided in the user terminal 3. Furthermore, each function may be distributed between the server device 2 and the user terminal 3.

[0134] In the above embodiment, the case where the parameters related to the vessel routing plan are set in advance has been described as an example, but the parameters related to the vessel routing plan may be set automatically. For example, parameters related to the vessel routing plan may be extracted using information on past vessel routing plans and used in the vessel routing plan to be created.

[0135] In the above embodiment, the case where the grouping information of loading ports is set by the user has been described as an example, but which loading port belongs to which loading port group may be set by the server device 2. In this case, the acquisition unit 21 acquires the automatically set grouping information.

[0136] Furthermore, in the above embodiment, the setting unit 22 sets unset parameters and the like as variables for a preset objective function F as an example. However, the objective function F may also be automatically generated.

[0137] Furthermore, in the above embodiment, a case has been described in which calculations are performed to minimize the value of the objective function F, but the calculation is not limited to a minimum case as long as the value of the objective function F is small. For example, calculations may be performed so that the value of the objective function F is equal to or less than a predetermined value. In other words, the degree to which the shipping route plan creation device is made to reduce the value of the objective function F (how appropriate a solution for unset parameters it is made to derive) can be set appropriately by the user depending on, for example, the processing capacity of the shipping route plan creation device, the balance between the time required for the shipping route plan creation device to create a shipping route plan and the desired frequency of creating shipping route plans, the accuracy of the shipping route plan desired by the user, etc.

[0138] Furthermore, in the above embodiment, when one ship calls at multiple loading ports belonging to the same loading port group, the number of port calls for that ship for that loading port group is counted as 1, but this is not limited to the above. As long as the number of port calls for that loading port group is counted as a number smaller than the number of loading ports (belonging to the same loading port group) that the ship calls at, the number of port calls is not limited to 1. For example, when a ship calls at five loading ports (belonging to the same loading port group), the number of port calls for that loading port group may be counted as 3 (less than 5).

[0139] In the above embodiment, the coefficients wG0, wG1, wG2, and wG3 in formula (2) are set to larger values ​​for loading port groups that are farther away from the discharging port, but this is not limiting. If it is desired to actively call at loading ports that belong to a specific loading port group (e.g., loading port group Gr2), the coefficients for that loading port group may be set lower than those for the others.

[0140] The information, parameters, etc. described in this disclosure may be expressed using absolute values, relative values ​​from a predetermined value, or other corresponding information. The mathematical formulas, etc. using these parameters may differ from those explicitly disclosed in this disclosure.

[0141] In this disclosure, the phrase "based on" does not mean "based only on," unless expressly stated otherwise. In other words, the phrase "based on" means both "based only on" and "based at least on."

[0142] The terms "determining" and "determining" in this disclosure may encompass a wide variety of actions. Each of "determining" and "determining" may include, for example, judging, calculating, computing, processing, deriving, investigating, searching (e.g., searching in a table, database, or other data structure), and ascertaining something as a "determining" or "determining." Also, each of "determining" and "determining" may include, for example, resolving, selecting, choosing, establishing, comparing, and the like ascribing something as a "determining" or "determining." That is, each of "determining" and "determining" may include ascribing some action as a "determining" or "determining."

[0143] In this disclosure, when expressions such as "obtaining / setting / using / based on / as input" (including similar expressions) are used, unless otherwise specified, this includes cases where the information itself is used, or where information that has been processed in some way (e.g., information that has been noise-added, normalized, features extracted from the information, intermediate representations of the information, etc.) is used. Furthermore, when a statement is made that a result is obtained "by obtaining / setting / using / based on / as input" (including similar expressions), this includes cases where the result is obtained based solely on the information, or cases where the result is influenced by other information, factors, conditions, and / or states other than the information in question, unless otherwise specified. Furthermore, when a statement is made that "outputs information" (including similar expressions), this includes cases where the information itself is used as output, or where information that has been processed in some way (e.g., information that has been noise-added, normalized, features extracted from the information, intermediate representations of various information, etc.) is used as output, unless otherwise specified.

Claims

1. A shipping plan creation device that derives a shipping plan for transporting raw materials from multiple loading ports to discharging ports by multiple ships, comprising: an acquisition unit that acquires information on multiple loading port groups into which each of the loading ports is grouped; a setting unit that sets an index that includes parameters related to the shipping plan as variables and corresponds to each of the loading port groups, indicating the total number of port calls of each of the ships for the loading port group, and in the case where one ship calls at multiple loading ports belonging to the same loading port group, the number of port calls of the ship is counted as being less than the number of port calls; and a calculation unit that derives each of the parameters related to the shipping plan so as to reduce the value of an objective function that is set by the sum of terms related to the index corresponding to each of the loading port groups.

2. A shipping plan creation device as described in claim 1, wherein, in the indicator, when one ship consecutively calls at multiple loading ports belonging to the same loading port group, the number of port calls of the ship to the loading port group is counted as a number less than the number of ports.

3. A shipping plan creation device as described in claim 1 or 2, wherein the calculation unit derives a combination of each of the parameters related to the shipping plan that satisfies predetermined constraints and minimizes the value of the objective function.

4. A shipping plan creation device according to claim 1 or 2, wherein the objective function includes a weighted linear sum obtained by multiplying the indicators corresponding to each of the loading port groups by a coefficient and adding the resulting coefficients.

5. The shipping plan creation device according to claim 1 or 2, wherein the loading ports are grouped such that loading ports that are close to each other belong to the same loading port group.

6. The shipping plan creation device according to claim 1 or 2, wherein the loading ports are grouped such that the loading ports that are closest to the discharging port belong to the same loading port group.

7. The shipping plan creation device according to claim 4, wherein the loading ports are grouped such that the loading ports that are closer to the discharging port belong to the same loading port group, and the coefficient is set to a larger value for the loading port group that is farther away from the discharging port.

8. A shipping plan creation device as described in claim 1 or 2, wherein a relay point is provided between the loading port and the discharging port, the objective function includes a parameter indicating whether or not the ship will pass through the relay point as the variable, and the calculation unit performs calculations so that the value of the objective function becomes smaller in both cases where the ship does not pass through the relay point and where the ship does pass through the relay point.

9. A shipping plan creation device as described in claim 1 or 2, wherein a relay point is provided between the loading port and the discharging port, the objective function is an index whose variables are parameters related to the shipping plan and includes an index indicating the difference between the raw materials scheduled to be transported to the discharging port and the raw materials required by the discharging port, and the index includes, as the variable, parameters related to the transportation of the raw materials from the relay point to the discharging port, and the calculation unit performs calculations so that the value of the objective function becomes small when the raw materials are transported from the relay point to the discharging port.

10. A method for creating a shipping plan that derives a shipping plan for transporting raw materials from multiple loading ports to discharging ports by multiple ships, comprising the steps of: acquiring information on multiple loading port groups into which the loading ports are grouped; setting an index that includes parameters related to the shipping plan as variables and corresponds to each of the loading port groups, indicating the total number of port calls made by each of the ships in the loading port group, and in the case where one ship calls at multiple loading ports belonging to the same loading port group, the number of port calls of the ship is counted as being less than the number of port calls; and deriving each of the parameters related to the shipping plan so as to reduce the value of an objective function that is set by the sum of terms related to the index corresponding to each of the loading port groups.

11. A shipping plan creation program that derives a shipping plan for transporting raw materials from multiple loading ports to discharging ports by multiple ships, comprising: a non-transitory computer-readable recording medium that records the shipping plan creation program, which causes a computer to function as: an acquisition unit that acquires information about multiple loading port groups into which each of the loading ports is grouped; a setting unit that includes parameters related to the shipping plan as variables and sets an index corresponding to each of the loading port groups, which indicates the total number of port calls made by each of the ships for the loading port group, and in the case where one ship calls at multiple loading ports belonging to the same loading port group, the number of port calls of the ship is counted as less than the number of port calls made by the multiple ports; and a calculation unit that derives each of the parameters related to the shipping plan so as to reduce the value of an objective function that is set by the sum of terms related to the index corresponding to each of the loading port groups.

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