Processing device, processing method, and program

Abstract

To provide a processing device, processing method and program for calculating a target inventory quantity that prevents inventory surplus or shortage at consumers, even in the presence of supply fluctuations of an object to consumers or demand fluctuations for the object at consumers.SOLUTION: A processing device 300 is provided, comprising a target inventory computation unit configured to use an acquisition plan and usage plan to compute a target inventory trend for each of multiple consumers (unloading ports (=steel plants).SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a processing device, a processing method, and a program, and is particularly suitable for use in managing inventory.

Background Art

[0002] Conventionally, when producing, distributing, and selling objects (such as products, semi-finished products, raw materials, and materials), it has been required to optimize the inventory level of the object. Therefore, a technique for accurately obtaining the time evolution of the target inventory (for example, the target inventory level per unit time) has been desired. As this type of technique, Patent Document 1 discloses deriving a safety stock number that minimizes the disposal cost of surplus inventory of common materials at the end of production across the entire factory without causing shortages of products. Further, Patent Document 2 discloses calculating a target value of the required inventory level required in the distribution route of a product for a predetermined period from a demand characteristic that is the relative ratio of the moving average demand during a predetermined period to the standard deviation indicating the variation in demand, and a supply characteristic including a safety stock coefficient or a service rate indicating the ratio of not causing shortages of the product.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, the technologies described in Patent Documents 1 and 2 assume that objects corresponding to the demand are supplied to the customers who manage the inventory. For example, due to an unexpected delay in the delivery to the customer, such as a significant delay in navigation, the supply of the object to the customer may not be sufficient. Therefore, there is a risk that the inventory level at the customer will be excessive or insufficient depending on the supply fluctuations. Also, for example, when the demand for an object is decreasing, if the supply volume of the object remains unchanged, the usage amount at the customer will decrease, so there is a risk that the inventory level at the customer will exceed the upper limit. Therefore, there is a risk that the inventory level at the customer will be excessive or insufficient due to demand fluctuations. As described above, if inventory management is performed according to the target inventory levels based on the technologies described in Patent Inventions 1 and 2, the risk of the inventory level being excessive or insufficient increases.

[0005] The present invention has been made in view of the above problems, and an object thereof is to calculate a target inventory level that suppresses an excess or deficiency in the inventory level at a customer even when there are supply fluctuations of an object to the customer and demand fluctuations of the object at the customer.

Means for Solving the Problems

[0006] The processing device of the present invention is a processing device that performs a process of calculating a target inventory transition indicating the time transition of the target inventory level of an object at a customer, and uses an acquisition plan indicating the time transition of the estimated acquisition amount of the object at the supplier of the object, and a usage plan indicating the time transition of the estimated usage amount of the object at each of a plurality of the customers, and includes a target inventory transition calculation unit that calculates the target inventory transition at each of the plurality of customers.

[0007] The processing method of the present invention is a processing method that performs a process of calculating a target inventory transition indicating the target inventory level of an object at a customer, and uses an acquisition plan indicating the time transition of the estimated acquisition amount of the object at the supplier of the object, and a usage plan indicating the time transition of the estimated usage amount of the object at each of a plurality of the customers, and includes a target inventory transition calculation step of calculating the target inventory transition at each of the plurality of customers.

[0008] The program of the present invention causes a computer to function as the target inventory transition calculation unit of the processing device.

Effects of the Invention

[0009] According to the present invention, even when there are fluctuations in the supply of an object to a customer or fluctuations in the demand for the object by the customer, it is possible to calculate a target inventory quantity that suppresses an excess or deficiency in the inventory quantity at the customer.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6A

Figure 6B

Figure 7

Figure 8

Figure 9

Modes for Carrying Out the Invention

[0011] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that, for comparisons of length, position, size, interval, etc., when the comparison targets are the same, in addition to the case where they are exactly the same, those that are different within a range that does not deviate from the gist of the invention (for example, those that are different within the tolerance range determined at the time of design) are also included.

[0012] (Concept) First, the concept obtained by the inventors in reaching the present embodiment described below will be described. FIG. 1 is a diagram showing a first example of inventory plans 101a to 101c of the same object in three customers. The inventory plan shows the time transition of the planned value of the inventory quantity of the object. The object may be any object as long as it is an object to be inventoried, such as a product, semi-finished product, raw material, and material. Here, an example is given in which a supplier supplies an object to a plurality of customers, and each of the plurality of customers manufactures a product using the object as a raw material, and the case where the inventory plan shown in FIG. 1 is an inventory plan of a raw material is exemplified. As a specific example of such a case, the raw material of a steel product supplied by at least one supplier is transported to at least one of a plurality of steelworks using a ship (carrier ship), and the case where the steel product is manufactured using the raw material at the steelworks is exemplified.

[0013] In FIG. 1, inventory plans 101a to 101c illustrate inventory plans created on the assumption that the inventory quantity can be freely determined as long as it falls within the range from lower limit values 102a to 102c to upper limit values 103a to 103c. The upper and lower limit values are arbitrary. For example, the upper limit value may be determined based on the size of the storage location, such as the maximum quantity of the storage location for inventory, and the lower limit value may be determined based on the safety stock. The inventory plans 101a to 101c shown in FIG. 1 are inventory plans for different customers (steel mills) (that is, inventory plans 101a, 101b, and 101c are inventory plans for the first customer, the second customer, and the third customer, respectively). In this case, as shown in FIGS. 1(a) and 1(c), as inventory plans for two customers (steel mills), inventory plans 101a and 101c are created in which there are periods when the inventory quantity is close to the lower limit values 102a and 102c. On the other hand, as shown in FIG. 1(b), as an inventory plan for another customer, there is a possibility that an inventory plan 101b may be created in which there is a period when the inventory quantity is close to the upper limit value 103b. Then, if inventory management is performed based on such inventory plans 101a to 101c, when there are fluctuations in the procurement plan of the object (raw material) at the supplier or the usage plan of the object at the customer, there is a risk of stockout (the inventory falls below the lower limit value) or overstock (the inventory exceeds the upper limit value). Also, when there are fluctuations in the procurement plan at the supplier or the usage plan at the customer for a certain type of object (raw material), there is a risk that the variation in the inventory quantity of that type of object among customers will increase. For example, for a certain type of object (raw material), at a certain time, there may be a situation where one customer has sufficient inventory while another customer has insufficient inventory. Also, even when distributing an object from a transport ship carrying a limited quantity of the object to a plurality of customers at a predetermined ratio such as according to demand or equally, considering that there will be customers with increasing inventory and customers with decreasing inventory according to demand, it is considered desirable to distribute so that all customers have sufficient margin from the upper and lower limits.

[0014] Therefore, the inventors calculated a target inventory trend indicating the time trend of the target inventory level (the target amount to which the inventory should change), separate from the upper and lower limit values of the inventory level, and thought that if an inventory plan was created to approach the target inventory trend, as shown in FIG. 2, it would be possible to create inventory plans 201a to 201c with sufficient margins from the upper and lower limit values (lower limit values 102a to 102c, upper limit values 103a to 103c). By doing so, even when fluctuations occur in the procurement plan at the supplier or the usage plan at the customer, it is possible to suppress the above-mentioned stockouts, excess inventory, and variations in inventory levels for each customer, so it is possible to achieve both out-of-stock prevention and inventory reduction.

[0015] Even in the technologies described in Patent Documents 1 and 2, the target value of the inventory level is simulated, but as described above, it is premised that the object is supplied as required by the customer. In contrast, the inventors thought that when calculating the target inventory trend, it is necessary to consider both the demand fluctuations of the object (the time change in the demand amount) at the customer who uses the object supplied from the supplier and the supply fluctuations (the time change in the supplyable amount) at the supplier who procures the object and supplies it to the customer. If inventory management is performed using such a target inventory trend, it is possible to suppress the excess or deficiency of the inventory level even when there are supply fluctuations and demand fluctuations of the object. For example, by creating an inventory plan that approaches (preferably matches) such a target inventory trend, it is possible to create an inventory plan that is robust against supply fluctuations and demand fluctuations of the object. The following embodiments have been made based on the above concept.

[0016] (Processing device 300) FIG. 3 is a diagram showing an example of the functional configuration of the processing device 300. The processing device 300 has, as hardware, one or more hardware processors such as a CPU (Central Processing Unit), and one or more memories such as a RAM (Random Access Memory) and a ROM (Read Only Memory), and executes various operations by executing one or more programs stored in the memory by one or more hardware processors. Further, the processing device 300 has an input device and an output device as hardware.

[0017] In the present embodiment, a case is exemplified in which the processing device 300 calculates a target inventory transition indicating the time transition of the target inventory amount at the customer for an object transported from the supply side to the customer using a transportation means. The target inventory transition may be any that indicates the time transition of the target inventory amount at the customer. For example, it may indicate the target inventory amount every 10 days in a certain period and the target inventory amount every 3 days in another period. In the present embodiment, a case is exemplified in which the target inventory transition indicates the target inventory amount per unit time at the customer and the unit time is constant. As described above, the object is a product, a semi-finished product, a raw material, a material, or the like. Note that the transportation means may be owned by the supply side or supplied by the demand side. The supplier of the object is, for example, one that has received a request for supply of the object from the customer, and is not limited to a trader that is the starting point of the distribution. The supplier may be, for example, a raw material mining trader, a raw material procurement trader, a factory (such as a manufacturer), a wholesaler, and a seller (such as a store).

[0018] The customer is, for example, one that requests supply of the object from the supplier and uses the object, and is not limited to a final consumer or the like. The customer may be, for example, a raw material procurement trader, a factory (such as a manufacturer), a wholesaler, and a seller (such as a store). Also, for example, in a steelworks having a plurality of factories, the upper process factory may be the supplier and the lower process factory may be the customer.

[0019] The transportation means may be any means for transporting an object from the supply side to the customer, and is not limited to the transportation means managed by the supplier. The transportation means may be, for example, the transportation means managed by a transporter other than the supplier. Also, the transportation means may be, for example, a vehicle (such as a truck, forklift, etc.), a ship, and an aircraft.

[0020] In FIG. 3 of this embodiment, a case where the processing device 300 includes a target inventory trend calculation unit 310, a plan creation unit 320, and an output unit 330 is illustrated. FIG. 4 is a diagram for explaining an example of a method for calculating the target inventory trend. As described above, the supplier, the customer, and the transportation means are not limited, but in the following description, for the convenience of explanation, if necessary, a case where the customer is a steel mill, the supplier is a raw material procurement company for steel products, and the transportation means is a ship (carrier ship) will be described as a specific example.

[0021] <Target inventory trend calculation unit 310> The target inventory trend calculation unit 310 calculates the target inventory trend for each of a plurality of customers using the acquisition plan and the usage plan. The acquisition plan indicates the time trend of the estimated quantity of objects to be acquired at the object supplier. The usage plan indicates the time trend of the estimated quantity of objects to be used for each of a plurality of customers. The acquisition plan may indicate the time trend of the estimated quantity of objects to be acquired at the object supplier, for example, indicating the estimated quantity to be acquired per period in a certain period, and indicating the estimated quantity to be acquired per month in another period. Similarly, the usage plan may indicate the time trend of the estimated quantity of objects to be used for each of a plurality of customers, indicating the estimated quantity to be used every three days in a certain period, and indicating the estimated quantity to be used every day in another period. In this embodiment, an example is illustrated where the acquisition plan indicates the estimated quantity of objects to be acquired per unit time at the object supplier, and the unit time is constant. Similarly, in this embodiment, an example is illustrated where the usage plan indicates the estimated quantity of objects to be used per unit time for each of a plurality of customers, and the unit time is constant. Note that the unit times of the target inventory trend, the acquisition plan, and the usage plan may be the same or different.

[0022] FIG. 5 is a diagram showing an example of an acquisition plan 510 and a usage plan 520. In FIG. 5(a), an example is illustrated in which the acquisition plan 510 includes object identification information, supplier identification information, and the scheduled acquisition quantity of the object by period. Here, it is assumed that one period is four months obtained by dividing one year into three-month periods. FIG. 5(a) shows the acquisition plan 510 for a certain period (from January 1, Y year to March 30, Y year). The acquisition plan for another period may be a different acquisition plan from the acquisition plan 510 shown in FIG. 5(a) or the same acquisition plan.

[0023] Also, in FIG. 5(a), an example is illustrated in which the object identification information includes the type and name of the object. In FIG. 5(a), an example is shown in which objects having the same type (K1) but different names (N1, N2) are treated as different objects and the acquisition plan 510 is created. For example, in FIG. 5(a), in a certain period (from January 1, Y year to March 30, Y year), it is shown that 1.8 million tons of an object of type K1 and name N1 are planned to be acquired from supplier U1.

[0024] As described above, FIG. 5(a) illustrates a case where the acquisition plan 510 shows the scheduled acquisition quantity for each period (that is, a case where the unit time of the acquisition plan 510 is one period), but the unit time is not limited to one period and may be, for example, one month, one hour, etc. Also, there may be a period in which the scheduled acquisition quantity for a certain object is 0 (zero). Further, FIG. 5(a) illustrates a case where the objects are classified by name and the acquisition plan 510 shows the scheduled acquisition quantity for each object name. However, the method of classifying the objects is not limited to such a method. For example, the objects may be classified by type. Also, such classification by category of the objects may not be performed.

[0025] In FIG. 5(b), an example is illustrated in which the usage plan 520 includes the scheduled usage date, customer identification information, object name, and usage quantity. For example, in FIG. 5(b), it is shown that customer U1 plans to use 800 tons of an object of name N1 on the scheduled usage date t 31 as shown.

[0026] In FIG. 5(b), a case where the usage plan 520 indicates the usage prediction amount for each day is illustrated (that is, a case where the unit time of the usage plan 520 is one day is illustrated). However, the unit time of the usage plan 520 is not limited to one day, and may be, for example, one month or one hour. Also, there may be a day when the usage prediction amount is 0 (zero) for a certain customer. Further, in FIG. 5(b), a case where the objects are classified by name and the usage plan 520 indicates the usage prediction amount for each object name is illustrated. However, the method of classifying the objects is not limited to such a method. For example, the objects may be classified by type. Also, such classification by category of the objects may not be performed.

[0027] In the present embodiment, a case where the target inventory transition calculation unit 310 acquires the acquisition plan 510 and the usage plan 520 from the input device 301 is illustrated. The input device 301 may include a database. In this case, the target inventory transition calculation unit 310 may acquire, for example, the acquisition plan 510 and the usage plan 520 stored in the database. Also, the input device 301 may include a user interface. In this case, the learning information acquisition unit 211 may acquire, for example, the acquisition plan 510 and the usage plan 520 input-operated with respect to the user interface. Also, the input device 301 may include an information processing device. In this case, the target inventory transition calculation unit 310 may receive, for example, the acquisition plan 510 and the usage plan 520 transmitted from the information processing device.

[0028] Also, in the present embodiment, a case where the target inventory transition calculation unit 310 calculates a transportation plan indicating the time change of the transportation prediction amount of the objects by the transportation means based on the acquisition plan 510 is illustrated. The transportation plan may be any plan that indicates the time transition of the transportation prediction amount of the objects by the transportation means. For example, it may indicate the transportation prediction amount for each day in a certain period and the transportation prediction amount for every three days in another period. In the present embodiment, a case where the transportation plan indicates the transportation prediction amount for each unit time of the objects by the transportation means and the unit time is constant is illustrated. FIG. 6A is a diagram showing an example of the transportation plan 610. In FIG. 6A, a case is illustrated where the transportation plan 610 includes identification information of the transportation means, identification information of the departure location, the scheduled departure date, the name of the object, and the planned transportation quantity. In this case, the target inventory transition calculation unit 310 acquires, in advance, for example, the identification information of the transportation means, the transportable quantity of the transportation means, the identification information of the departure location, and the scheduled departure date. Since the acquisition form of this information may be the same as that of the acquisition plan 510 and the usage plan 520, the detailed description thereof is omitted here.

[0029] For example, the target inventory transition calculation unit 310 specifies the planned acquisition quantity of each object supplied from the supplier corresponding to each departure location based on the acquisition plan 510. Then, the target inventory transition calculation unit 310 may calculate the transportation means for transporting each object and the planned transportation quantity of each object based on the transportable quantity of each transportation means departing from each departure location and the planned acquisition quantity of each object supplied from the supplier corresponding to the departure location. For example, in FIG. 6A, it is shown that the transportation means C1 is scheduled to depart from the departure location P1 at time t and transport 200,000 tons of the object with the name N1. 11 It is scheduled to depart and transport.

[0030] Also, in order to simplify the description in this embodiment, it is assumed that the departure location (port of loading) and the supplier (shipper) correspond one-to-one, and objects (raw materials) are not transported from one supplier (shipper) to a plurality of departure locations (ports of loading). Therefore, in FIGS. 5(a) and 6A, without distinguishing between the departure location (port of loading) and the supplier (shipper), the identification information of these is denoted as P1. However, it is not necessarily required to do so, and these may be distinguished. In this case, the information of the supplier (shipper) may be included in the transportation plan 610.

[0031] In addition, in FIG. 6A, a case where the transportation plan 610 indicates the daily transportation quantity is illustrated (that is, a case where the unit time of the transportation plan 610 is one day is illustrated). However, the unit time of the transportation plan 610 is not limited to one day, and may be, for example, one month and one hour. However, it is preferable that the unit time of the transportation plan 610 is shorter than the unit time of the acquisition plan 510. Further, in FIG. 6A, a case where objects are classified by name and the transportation plan 610 indicates the transportation quantity by name is illustrated. However, the method of classifying objects is not limited to such a method. For example, objects may be classified by type. Also, such classification by category of objects may not be performed. Also, a plan in which one transportation means transports objects of different categories (different names in FIG. 6A) may be included in the transportation plan 610.

[0032] In addition, the transportation plan is not limited to the transportation plan 610 as shown in FIG. 6A. For example, there may be a case where objects are transported from one supplier (shipper) to one or more customers using the same transportation means. In this case, for example, the target inventory transition calculation unit 310 may calculate a transportation plan 620 as shown in FIG. 6B based on the acquisition plan 510 shown in FIG. 5(a). When there are a plurality of suppliers (shippers), the target inventory transition calculation unit 310 may calculate a transportation plan 620 for each of the plurality of suppliers (shippers). In FIG. 6B, a transportation plan 620 for the case where transportation is performed every 10 days (that is, the unit time is 10 days) is illustrated. Also, in FIG. 6B, a transportation plan 620 for the case where 200,000 tons obtained by dividing 1.8 million tons, which is the acquisition quantity (purchase quantity) of brand N1 in a certain period (3 months = 90 days) shown in FIG. 5(a), into 9 equal parts (= 90 days / 10 days) are shipped every 10 days is illustrated.

[0033] In addition, in the present embodiment, a case where the target inventory transition calculation unit 310 calculates the transportation plans 610 and 620 is illustrated. However, it is not necessarily required to be like this. For example, the target inventory transition calculation unit 310 may acquire the transportation plans 610 and 620 calculated outside the processing device 300. In this case, the target inventory transition calculation unit 310 may not acquire the acquisition plan 510.

[0034] Also, for example, when the unit time of the procurement plan 510 is one day, the target inventory transition calculation unit 310 will acquire the procurement plan 510 for each day (that is, it will acquire 30 or 31 procurement plans 510 as a one-month procurement plan 510). In this case, the target inventory transition calculation unit 310 may use the procurement plan 510 as a transportation plan.

[0035] Also, in the present embodiment, in addition to at least one of the procurement plan 510 and the transportation plan 610 and the usage plan 520, the target inventory transition calculation unit 310 further uses a reception estimate that includes information capable of specifying the expected arrival time of the object on the customer side to calculate the target inventory transition for each of a plurality of customers. FIG. 7 is a diagram showing an example of the reception estimate 710.

[0036] In FIG. 7, an example is illustrated where the reception estimate 710 includes the identification information of the transportation means, the identification information of the destination, the expected arrival date, and the name of the object. The inventors have found that if the supplier can supply the objects of each name to all customers according to the ratio of the usage quantity required by each customer, each customer can stably maintain the inventory quantity of each name. Based on this idea, in the reception estimate, a destination may be set for all customers who use an object of a certain name supplied from the supplier. In this case, it is normal to have a plurality of destinations for unloading the objects of the same name. At this time, if the transportation means has stopped at another destination first, the expected arrival date at the subsequent destination will take an extra number of days corresponding to the number of days of that stop. Therefore, the expected arrival date obtained by adding the number of days of that stop to the number of days when directly arriving at the subsequent destination may be set as the expected arrival date at the subsequent destination. For example, in FIG. 7, the transportation means C1 transporting the object of name N1 first unloads the object of name N1 supplied from the supplier at U1 and then at U2, each at t 31 、t 32It is shown that it is scheduled to arrive. For example, when one means of transportation can arrive at a maximum of two arrival locations, it is possible that one means of transportation C1 arrives at a plurality of arrival locations in this way. For example, after first arriving at U1, it may then arrive at U2. Also, after first arriving at U2, it may then arrive at U1. Since it has stopped at other arrival locations first, the extra number of days from the first scheduled arrival date to the subsequent arrival locations can be calculated using, for example, at the relevant arrival location, the actual value of the number of days taken from the first arrival location when the relevant arrival location was the second arrival location. In this case, it may be the average of the actual values for each first arrival location, or the average value of the actual values without distinguishing the first arrival location.

[0037] Also, in order to simplify the explanation in this embodiment, it is assumed that there is a one-to-one correspondence between the arrival location (port of unloading) and the customer (steel mill), and it is assumed that an object (raw material) is not transported from one arrival location (port of unloading) to a plurality of customers (steel mills). Therefore, in FIGS. 5(b) and 7, without distinguishing between the customer (steel mill) and the arrival location (port of unloading), this identification information is denoted as U1. However, it is not necessarily necessary to do so in this way, and the estimated receipt forecast with the customer (steel mill) as the arrival location may be used. In this case, the scheduled arrival date is determined in consideration of the transportation time of the object (raw material) from the arrival location (port of unloading) to the customer (steel mill).

[0038] Also, in FIG. 7, an example is given in which the information indicating the scheduled arrival time of the object (scheduled arrival date) is included in the estimated receipt forecast 710. However, the information capable of specifying the scheduled arrival time of the object is not limited to such information. For example, the transportation time of each object may be included in the estimated receipt forecast as information capable of specifying the scheduled arrival time of the object. In this case, the target inventory transition calculation unit 310 may calculate, for example, the year and month corresponding to the time when the transportation time has elapsed from the scheduled departure date calculated as described above (refer to the scheduled departure date of the transportation plan 610 in FIG. 6A) as the scheduled arrival date.

[0039] In addition, FIG. 7 illustrates the case where the unit at the scheduled arrival time is one day. However, the unit at the scheduled arrival time is not limited to one day, and may be, for example, one month and one hour. Also, there may be a day when the means of transportation does not arrive at a certain destination. Further, in FIG. 7, the case where objects are classified by name and the estimated reception 710 indicates the scheduled arrival time by object name is illustrated. However, the method of classifying objects is not limited to such a method. For example, objects may be classified by type. Also, such classification by category of objects may not be performed. The acquisition form of the estimated reception 710 may be the same as, for example, the acquisition plan 510 and the usage plan 520, and thus the detailed description thereof is omitted here.

[0040] As described above, in FIG. 6A, the means of transportation C1 is shown to be scheduled to depart from the departure place P1 at time t 11 and transport 200,000 tons of the object of name N1. In FIG. 4, “N1: 200,000 tons”, “Loading Port: P1”, “Departure Time: t 11 ” shown below the transport ship C1 represents this. Also, in FIG. 4, “Loading Port: P2”, “Departure Time: t 12 ”, “Loading Port: Pn”, “Departure Time: t 1n ” shown below the transport ships C2, Cn indicate that the transport ships C2,..., Cn are scheduled to depart from the departure places (loading ports) P2,..., Pn at time t 12 ,..., t 1n and perform transportation. In FIG. 4, for the convenience of explanation and notation, the notation of other information about the transport ships C2, Cn is omitted.

[0041] Also, as described above, in FIG. 7, the means of transportation C1 that transports the object of name N1 is shown to be scheduled to arrive at the arrival places U1, U2 at times t 31 and t 32 respectively. In FIG. 4, “Unloading Port: U1”, “Arrival Time: t 31 ”, “Unloading Port: U2”, “Arrival Time: t 32」indicates this. Incidentally, as will be described later, the carrier ship C1 is scheduled to unload the raw material of brand N1 at the port of arrival U1, then depart from the port of arrival U1 towards the port of arrival U2, and unload the raw material of brand N1 at the port of arrival U2. To illustrate this, the carrier ship C1 will call at U1 and then call at U2 (t 31 <t 32 ).

[0042] As described above, it is preferable to use the estimated incoming quantity 710 for reception because, for example, the transportation time by the transportation means can be considered. However, it is not always necessary to use the estimated incoming quantity 710 for reception. For example, in a steelworks equipped with multiple factories, when the upper-process factory is the supplier and the lower-process factory is the customer, and the scheduled departure date and the scheduled arrival date are the same day, it is not necessary to use the estimated incoming quantity 710 for reception.

[0043] An example of the processing of the target inventory transition calculation unit 310 when calculating the target inventory transition using the transportation plan 610, the usage plan 520, and the estimated incoming quantity 710 for reception will be described below with reference to the flowcharts of FIGS. 4 and 8. In the following description, as needed, the transportation means, the departure location, the arrival location, departure, arrival, customer, object, and name of the object will be described using specific examples of a carrier ship, a loading port, a port of arrival, departure from the port, arrival at the port, a steelworks, a raw material, and the brand of the raw material, respectively. Also, in the following description, to simplify the explanation, it is assumed that the day when the object (raw material) arrives at the arrival location (port of arrival) is the same as the day when the object (raw material) arrives at the customer (steelworks), and the arrival location (port of arrival) and the customer (steelworks) are not distinguished. Also, it is assumed that the day when the object (raw material) is supplied (shipped) from the supplier (shipper) is the same as the day when the transportation means (ship) departs from the departure location (loading port), and the supplier (shipper) and the departure location (loading port) are not distinguished.

[0044] First, in step S801, the target inventory transition calculation unit 310 obtains the initial values S 01 , S 02 of the target inventory levels at each port of arrival (= steelworks) U1, U2. In FIG. 4, the calculation target period of the target inventory transition 410 is from t s to t eIllustrate the case where it is the period up to (Note that at the time of step S801, the target inventory transition 410 is not calculated). The initial value S of the target inventory quantity 01 , S 02 is the target inventory quantity at the first date t s of the calculation target period of the target inventory transition 410. In the following description, the calculation target period of the target inventory transition is referred to as the planning period as needed. As the target inventory transitions 410a and 410b at each unloading port (= steelworks) U1 and U2, illustrate the case where the target inventory transitions 410a and 410b are calculated for each raw material brand N1 and N2. In the following description, the raw material brand is abbreviated as brand as needed. In the present embodiment, the target inventory transition calculation unit 310 illustrates the case where the initial values S 01 , S 02 obtain the initial values for each of the brands N1 and N2 as the initial values of the target inventory quantity at each unloading port (= steelworks) U1 and U2.

[0045] In the following description, the unloading ports (= steelworks) U1 and U2, the loading ports P1 and P2, the unloading ports U1 and U2, the transport ships C1, C2, ···, Cn, the brands N1 and N2, as needed, are represented as the unloading port (= steelworks) U, the loading port P, the unloading port U, the transport ship C, and the brand N, respectively. Also, the target inventory transitions 410a and 410b are collectively referred to as the target inventory transition 410 as needed. Also, the initial values S 01 , S 02 of the target inventory quantity are collectively referred to as the initial value S0 of the target inventory quantity as needed.

[0046] The initial value S0 of the target inventory quantity of each brand N at each unloading port (= steelworks) U may be calculated using, for example, the actual value of the inventory quantity of the brand N at the unloading port (= steelworks) U. For example, the initial value S0 of the target inventory quantity of each brand N at each unloading port (= steelworks) U may be the average value of the inventory quantity of the brand N at the unloading port (= steelworks) U in the past month, or may be the current inventory quantity of the brand N at the unloading port (= steelworks) U. In this case, the target inventory transition calculation unit 310 acquires the actual value of the inventory quantity of the raw material of each brand N at each unloading port (= steelworks) U. The acquisition form of the actual value may be the same as that of the acquisition plan 510 and the usage plan 520, for example, so the detailed description thereof is omitted here.

[0047] Next, in step S802, the target inventory trend calculation unit 310 acquires and sets the unit time ΔT1 of the target inventory trend 410 (note that the target inventory trend 410 is not calculated even at the time of step S802). The acquisition form of the unit time ΔT1 of the target inventory trend 410 may be the same as the acquisition forms of the procurement plan 510, the usage plan 520, and the estimated receipt expectation 710, for example, so the detailed description thereof is omitted here.

[0048] The unit time ΔT1 of the target inventory trend 410 is, for example, 10 days. In the present embodiment, a case where the unit time ΔT1 of the target inventory trend 410 is longer than the unit times (1 day in FIG. 5(b)) of the usage plans 520a and 520b is exemplified. In FIG. 4, the target inventory trend calculation unit 310 determines the year, month, and day t s corresponding to the time when an integer multiple of the unit time ΔT1 is added to the first day of the planning period. 21 ~t 27 is calculated.

[0049] Next, in step S803, the target inventory trend calculation unit 310 calculates the planned unloading quantity of the raw materials for each means of transportation (transport ship C), for each category of raw materials (brand N), for each customer (Yanggang (= steelworks) U), and for each scheduled arrival time (scheduled arrival date at the port) (note that the target inventory trend 410 is not calculated even at the time of step S803). In the present embodiment, a case where the target inventory trend calculation unit 310 calculates the unloading quantity using the distribution ratio of the planned transportation quantity of each object (brand) transported by each means of transportation (transport ship C) to each customer (Yanggang (= steelworks) U) is exemplified.

[0050] As such a distribution ratio, in the present embodiment, a case where a first distribution ratio based on the planned usage quantity of the object (brand) in each of a plurality of customers (Yanggang (= steelworks) U) and a second distribution ratio based on the transportation order of the object when one means of transportation (transport ship C) transports the object (material) to a plurality of customers (Yanggang (= steelworks) U) are used is exemplified.

[0051] First, a specific example of the first distribution ratio will be described. In the present embodiment, a case where the first distribution ratio is a ratio based on the usage planned amounts of each of a plurality of consumers (Yanggang (= steelworks) U) included in the usage plan 520 on the same usage planned date will be exemplified. By doing so, for example, it is possible to maintain the balance of the inventory amounts of a certain type of object for a plurality of consumers who plan to use the object in the same period at that time.

[0052] For example, in FIG. 4, it is specified from the transportation plan 610 that the transport ship C1 is planned to transport 200,000 tons of the raw material of brand N1. Also, it is specified from the reception estimate forecast 710 that the transport ship C1 is scheduled to call at the first Yanggang (= steelworks) U1 and then the subsequent Yanggang U2 on the scheduled arrival dates t 31 , t 32 respectively. Also, it is specified from the reception estimate forecast 710 that at the first Yanggang (= steelworks) U1, 800 tons of the raw material of brand N1 is planned to be used on the usage planned date t 31 , and at the subsequent Yanggang (= steelworks) U2, 900 tons of the raw material of brand N1 is planned to be used on the usage planned date t 32 . The target inventory transition calculation unit 310 performs such specification for each Yanggang (= steelworks) U, for each usage planned date, and for each brand N.

[0053] Then, the target inventory transition calculation unit 310 can calculate the total amount of the usage planned amounts of the raw materials at all Yanggang (= steelworks) U for each usage planned date and for each brand N. For example, the target inventory transition calculation unit 310 can calculate the total amount of the usage planned amounts of the raw material of brand N1 at all Yanggang (= steelworks) U on the usage planned date t 31 . Similarly, the target inventory transition calculation unit 310 can calculate the total amount of the usage planned amounts of the raw material of brand N1 at all Yanggang (= steelworks) U on the usage planned date t 32 .

[0054] The target inventory transition calculation unit 310 is at the Yanggang (= steelworks) U1 where the transport ship C1 calls at the scheduled arrival date t 31 on that date t 31The planned usage amount for use at t (= 800 tons) is divided by the total amount of the planned usage amount of the raw material of brand N1 at all ports of call U (= steelworks) at the date t 31 to calculate the value obtained by dividing it by the total amount at all ports of call U (= steelworks), and this value is used as the first allocation ratio to the port of call U1 of the transport ship C1 carrying brand N1 that is scheduled to call at the port of call U1 at the scheduled arrival date t 31 at the port of call U1.

[0055] In FIG. 4, the "800 / (800 + 700 + ···) × 3 / 10" shown on the dashed line attached above t 31 represents the first allocation ratio. Note that the "800" in "800 / (800 + 700 + ···)" is the planned usage amount at the planned usage date t 31 in the usage plan 520a shown in FIG. 4, and the "700" is the planned usage amount at the planned usage date t 31 in the usage plan 520b shown in FIG. 4. Note that the "+ ···" in "(800 + 700 + ···)" indicates adding the planned usage amounts at the planned arrival dates t 31 at ports of call U other than the ports of call U1 and U2.

[0056] Similarly, the target inventory trend calculation unit 310 divides the planned usage amount for use at the date t (= 900 tons) at the port of call U2 where the transport ship C1 is scheduled to call at the scheduled arrival date t 32 by the total amount of the planned usage amount of the raw material of brand N1 at all ports of call U (= steelworks) at the date t 32 to calculate the value obtained by dividing it by the total amount at all ports of call U (= steelworks), and this value is used as the first allocation ratio to the port of call U2 of the transport ship C1 carrying brand N1 that is scheduled to call at the port of call U2 at the scheduled arrival date t 32 at the port of call U2. 32 In FIG. 4, for the target inventory trend 410b at the date t

[0057] 32 ​Of the “200,000 × 900 / (500 + 900 + ···) × 7 / 10” shown above the dashed line attached to it, “900 / (500 + 900 + ···)” represents the first distribution ratio. Note that “900” in “900 / (500 + 900 + ···)” is the planned usage quantity at the planned usage date t 32 in the usage plan 520b shown in FIG. 4, and “500” is the planned usage quantity at the planned usage date t 32 in the usage plan 520a shown in FIG. 4. Note that “+···” in “(500 + 900 + ···)” indicates that the planned usage quantities at the planned arrival dates t 32 at the ports of call U other than the ports of call U1 and U2 ( = steelworks) are added.

[0058] The target inventory trend calculation unit 310 calculates the first distribution ratio as described above, for example, for each carrier ship C, for each brand N, for each port of call U ( = steelworks), and for each planned arrival date. Note that the first distribution ratio is not limited to the ratio based on the planned usage quantities at the same planned usage date of each customer (port of call U ( = steelworks)) included in the usage plan 520. For example, a ratio based on the planned usage quantities within a predetermined period (e.g., three days) centered around the planned usage date of each customer (port of call U ( = steelworks)) included in the usage plan 520 may be used as the first distribution ratio. Also, a ratio of the planned usage quantity at the planned usage date of the customer (port of call U ( = steelworks)) for which the target inventory trend 410 is calculated to a preset reference quantity may be used as the first distribution ratio.

[0059] Next, specific examples of the second distribution ratio will be described. In the present embodiment, an example is given in which the second distribution ratio uses a ratio based on the arrival order of the transportation means to the customers when one transportation means (transport ship C1) transports an object (brand N) to a plurality of customers (loading ports (= steelworks)) U. In this way, it is possible to adjust the target inventory transition in a plurality of customers (loading ports (= steelworks)) U that receive the supply of the object (brand N) from one transportation means (transport ship C1). For example, based on the first distribution ratio, by increasing the distribution of the object (brand N) to the customer (loading port (= steelworks)) U with the earlier arrival order, it is possible to suppress a decrease in the distribution of the object (brand N) to the customer (loading port (= steelworks)) U with the later arrival order. Conversely, based on the first distribution ratio, by decreasing the distribution of the object (brand N) to the customer (loading port (= steelworks)) U with the earlier arrival order, it is possible to suppress an excessive distribution of the object (brand N) to the customer (loading port (= steelworks)) U with the later arrival order. The second distribution ratio may be determined based on past performance, for example. The past performance may be, for example, the transportation performance of the object (brand N), and may be determined based on the actual performance values of the unloading quantity of the object for the customers who arrived first to nth (n is an integer of 2 or more). Here, for simplicity of explanation, an example is given in which one transportation means (transport ship C1) transports an object (brand N) to a maximum of two customers (loading ports (= steelworks)) U.

[0060] For example, in FIG. 4, it can be specified from the estimated reception 710 that after the transport ship C1 unloads the raw material of the brand N1 at the loading port U1, it will leave the loading port U1 and head for the loading port U2 and unload the raw material of the brand N1 at the loading port U2. The target inventory transition calculation unit 310 performs such specification for each loading port (= steelworks) U and each brand N.

[0061] Then, at each loading port (= steelworks) U, it is specified whether the transport ship C that calls at the loading port (= steelworks) U calls at a plurality (here, two) of loading ports (= steelworks) U, and the arrival order at the loading port (= steelworks) U when the transport ship C that calls at the loading port (= steelworks) U calls at a plurality (here, two) of loading ports (= steelworks) U.

[0062] The target inventory trend calculation unit 310 selects a second distribution ratio that is determined in advance according to the order of arrival at the port. The second distribution ratio may be a smaller value as the order of arrival at the port is earlier, or a smaller value as the order of arrival at the port is later, or the values for some orders of arrival at the port may be the same. Also, the second distribution ratio may be determined, for example, for each category of raw materials (brand N), for each means of transportation (transport ship C), or may be determined without depending on these. For example, from past performance at the destination, when the destination is the first destination, the unloading ratio at the destination for the total transported amount of the name of the object (= the amount of the object of the name unloaded from the means of transportation at the destination ÷ the total transported amount of the object of the name in the means of transportation) and when the destination is the second destination, the unloading ratio at the destination for the total transported amount of the name of the object are aggregated and calculated. When the second distribution ratio is determined in advance as described above, the target inventory trend calculation unit 310 acquires the second distribution ratio in advance. The acquisition form of the second distribution ratio may be the same as, for example, the acquisition plan 510 and the usage plan 520, so the detailed description thereof is omitted here.

[0063] For example, when the order of arrival at the port of the transport ship C transporting the raw material of brand N1 is 1 and the second distribution ratio is 30% (3 / 10), and when the order of arrival at the port is 2 and the second distribution ratio is 70% (7 / 10), at the ports of unloading U1 and U2, the raw material of brand N1 is unloaded at a ratio of 3:7. In FIG. 4, the "3 / 10" in "200,000 × 800 / (800 + 700 + ···) × 3 / 10" shown on the broken line attached above t 31 represents the second distribution ratio. Also, the "7 / 10" in "200,000 × 900 / (500 + 900 + ···) × 7 / 10" shown on the broken line attached to the date t 32 of the target inventory trend 410b represents the second distribution ratio.

[0064] On the other hand, when the transport ship C arriving at the port of unloading (= steelworks) U arrives only at the port of unloading (= steelworks) U (that is, when the number of arrivals at the port is 1), the target inventory trend calculation unit 310 sets 1 as the second distribution ratio to the port of unloading (= steelworks) U.

[0065] For example, the target inventory trend calculation unit 310 calculates the second allocation ratio as described above for each carrier ship C, each brand N, and each unloading port (= steelworks) U. Note that the second allocation ratio is not limited to the ratio based on the arrival order of the transport means to the customers when one transport means (carrier ship C1) transports an object (brand N) to a plurality of customers (unloading ports (= steelworks)) U. Any ratio based on the transport order of the object when one transport means (carrier ship C1) transports an object (brand N) to a plurality of customers (unloading ports (= steelworks)) U is acceptable. For example, a value independent of the arrival order may be used as the second allocation ratio. For example, when a certain transport means (carrier ship C1) supplies (unloads) objects (raw materials) of the same category (brand) to Q customers (unloading ports (= steelworks)) U, the second allocation ratio to all customers (unloading ports (= steelworks)) U may be set to 1 / Q.

[0066] After calculating the first allocation ratio and the second allocation ratio as described above, when the carrier ship C is scheduled to unload the raw material of brand N at the unloading port U on the scheduled arrival date, the target inventory trend calculation unit 310 calculates, as the estimated unloading quantity, the product of the estimated transport quantity of the raw material of brand N on the carrier ship C and the first allocation ratio corresponding to the carrier ship C, the brand N, the unloading port U, and the scheduled arrival date, and the second allocation ratio corresponding to the carrier ship C, the brand N, and the unloading port U.

[0067] The target inventory trend calculation unit 310 calculates the estimated unloading quantity as described above for each carrier ship C, each brand N, each unloading port (= steelworks) U, and each scheduled arrival date. Then, the target inventory trend calculation unit 310 aggregates the estimated unloading quantities with the same brand N, unloading port (= steelworks) U, and scheduled arrival date to calculate the estimated unloading quantity for each brand N, each unloading port (= steelworks) U, and each scheduled arrival date. For example, if the number of carrier ships C arriving at one unloading port (= steelworks) U per day is 1, in FIG. 4, on the scheduled arrival date t 31 it is planned to unload "200,000×800 / (800 + 700 + ···)×3 / 10" tons of the raw material of brand N1 at the unloading port U1, and on the scheduled arrival date t 32It is shown that the raw material of brand N1 is scheduled to be unloaded at Pier U2 (= steelworks) U2 in an amount of "200,000 × 900 / (500 + 900 + ···) × 7 / 10" tons. In the present embodiment, as described above, as an example of the supply planned quantity of an object for each category, each customer, and each scheduled arrival time, the unloading planned quantity for each brand N, each Pier U (= steelworks), and each scheduled arrival date can be obtained. In the following description, the supply planned quantity of an object for each category, each customer, and each scheduled arrival time is referred to as the scheduled arrival time unit unloading planned quantity as needed, and the unloading planned quantity for each brand N, each Pier U (= steelworks), and each scheduled arrival date is referred to as the arrival time unit unloading planned quantity as needed.

[0068] Next, in step S804, the target inventory transition calculation unit 310 calculates the target inventory transitions 410a and 410b for each category (brand N) and each customer (Pier U (= steelworks) U) based on the scheduled arrival time unit unloading planned quantity (arrival time unit unloading planned quantity).

[0069] When the unit of the scheduled arrival time (scheduled arrival date) is the same as the unit time ΔT1 of the target inventory transition 410, the target inventory transition 410 may be calculated by adding the scheduled arrival time unit unloading planned quantity (arrival time unit unloading planned quantity) calculated in step S803 and subtracting the usage planned quantity at the scheduled arrival time from the target inventory quantity one unit time ΔT1 before the scheduled arrival time. That is, the value of the target inventory transition 410 for each unit time ΔT1 = the target inventory quantity one unit time ΔT1 before the scheduled arrival time + the scheduled arrival time unit unloading planned quantity (arrival time unit unloading planned quantity) - the usage planned quantity at the scheduled arrival time may also be used.

[0070] However, in the present embodiment, a case where the unit time ΔT1 of the target inventory transition 410 (for example, 10 days) is longer than the unit (1 day) of the scheduled arrival time (scheduled arrival date) is illustrated. Therefore, a case where the target inventory transition calculation unit 310 calculates the target inventory transition 410 as follows is illustrated.

[0071] First, the target inventory trend calculation unit 310 determines which time range of the target inventory trend 410 (e.g., the time range from t 21 to t 22 (=t 21 + 10 days) in FIG. 4) the scheduled arrival date indicated by the unloading quantity per unit at arrival belongs to, where the target inventory trend 410 is divided by a unit time ΔT1. The target inventory trend calculation unit 310 performs such determination for all unloading quantities per unit at arrival for each brand N and each unloading port (= steelworks) U.

[0072] Then, the target inventory trend calculation unit 310 adds up the unloading quantities per unit at arrival included in the same time range for each brand N and each unloading port (= steelworks) U. In this embodiment, an example is given where the added value thus obtained is used as the target inventory quantity in the corresponding time range. For example, in FIG. 4, the unloading quantity per unit at arrival of "200,000 × 800 / (800 + 700 + ···) × 3 / 10" tons is the unloading quantity per unit at arrival at the scheduled arrival date t 31 . Therefore, the unloading quantity per unit at arrival of "200,000 × 800 / (800 + 700 + ···) × 3 / 10" tons is used for calculating the target inventory quantity in the time range from t 21 to t 22 of the target inventory trend 410a of brand N1 at unloading port (= steelworks) U1. In this case, the target inventory quantity in the time range from t 21 to t 22 of the target inventory trend 410a is calculated by adding the added value of the unloading quantities per unit at arrival included in the time range from t 21 to t 21 to the target inventory quantity at one unit time ΔT1 before the scheduled arrival time (the target inventory quantity at t 22 ) and subtracting the used quantity in the time range from t 21 to t 22 . In FIG. 4, an example is given where the target inventory quantity at t 21 is the initial value S 01 of the target inventory quantity.

[0073] The target inventory trend calculation unit 310 can calculate the target inventory trends 410a and 410b for each brand N and each transfer port (= steelworks) U by calculating the target inventory quantity as described above for all time ranges of all the target inventory trends 410.

[0074] Here, at least one of the upper limit value and the lower limit value may be set for each of the target inventory trends 410a and 410b for each brand N and each transfer port (= steelworks) U. In this case, for example, if the added value in a certain time range of a certain target inventory trend 410 exceeds the upper limit value of the target inventory trend 410, the target inventory quantity in this time range may be set as the upper limit value, or may be set as a value smaller than the upper limit value (for example, r1 × upper limit value (where 0 < r1 < 1)). Also, for example, if the added value in a certain time range of a certain target inventory trend 410 is less than the lower limit value of the target inventory trend 410, the target inventory quantity in this time range may be set as the lower limit value, or may be set as a value larger than the lower limit value (for example, r × lower limit value (where r > 1)).

[0075] <Planning unit 320> Based on the calculation result of the evaluation index that evaluates the difference between the time trend of the inventory quantity of the object at the customer and the target inventory trend, the planning unit 320 creates an inventory plan that shows the time trend of the planned value of the inventory quantity of the object at the customer. The inventory plan may be any plan that shows the time trend of the planned value of the inventory quantity of the object at the customer. For example, in a certain period, it may show the planned value of the inventory quantity per day, and in another period, it may show the planned value of the inventory quantity per week. In this embodiment, an example is given where the inventory plan shows the planned value of the inventory quantity of the object at the customer per unit time, and the unit time is constant.

[0076] In this embodiment, in step S805 of FIG. 8, an example is given where the planning unit 320 solves the planned values of the inventory quantities for each of the ports U (= steelworks), brands N, and dates using known methods such as mathematical programming methods, rule-based methods, and metaheuristics. In this case, for example, an evaluation index is used that indicates that the closer the planned value of the inventory quantity for each of the ports U (= steelworks), brands N, and dates is to the target inventory quantity on that date in the target inventory trend 410 for the relevant port U and the relevant brand N (i.e., the smaller the absolute value of their difference), the higher the evaluation. Also, at that time, at least one of the upper limit value and the lower limit value for the inventory quantity may be set. In this case, the planning unit 320 calculates the planned value of the inventory quantity so as to satisfy a constraint condition (constraint equation) indicating that the planned value of the inventory quantity does not exceed the upper limit value. Also, the planning unit 320 calculates the planned value of the inventory quantity so as to satisfy a constraint condition (constraint equation) indicating that the planned value of the inventory quantity does not fall below the lower limit value.

[0077] Note that the upper limit value and the lower limit value may be the same as or different from the upper limit value and the lower limit value described above that the target inventory trend calculation unit 310 uses when calculating the target inventory trend 410. Also, evaluation indicators other than the evaluation indicator for evaluating the difference from the target inventory trend, such as an evaluation indicator for evaluating the transportation cost, may be included.

[0078] Also, the formulation for creating the inventory plan (for example, the formulation of the evaluation function and constraint conditions (constraint equations) using the evaluation indicators described above) and the algorithm of the solution method (for example, algorithms such as mathematical programming methods, rule-based methods, and metaheuristics) can be realized by those skilled in the art using known techniques, so detailed description thereof is omitted here.

[0079] Also, it is preferable to create an inventory plan as in this embodiment. However, it is not necessarily required to do so. For example, the target inventory trend 410 may be treated as the inventory plan. In this case, the processing device 300 may not include the planning unit 320.

[0080] <Output unit 330> The output unit 330 outputs information indicating the inventory plan. In this embodiment, in step S806 of FIG. 8, the case where the output unit 330 outputs the information indicating the inventory plan created in step S805 to the output device 302 is exemplified. The output device 302 may include a computer display. In this case, the output unit 330 causes, for example, the information indicating the inventory plan to be displayed on the computer display. Further, the output device 302 may include an information processing device. In this case, the output unit 330 may transmit, for example, the information indicating the inventory plan to the information processing device. Further, the output device 302 may include a storage medium. In this case, the output unit 330 may store, for example, the information indicating the inventory plan in the storage medium.

[0081] <Calculation example> FIG. 9 is a diagram showing an example of the calculation result of the inventory plan. In FIG. 9, inventory plans 901 to 905 and 911 to 915 of raw materials of the same brand in each of a plurality of steelworks, and inventory plans 906 and 916 of raw materials of the said brand in all of the plurality of steelworks are shown. In FIGS. 9(a) and 9(b), the inventory amount is represented as the number of days of inventory, and the number of days of inventory is a dimensionless quantity.

[0082] FIG. 9(a) shows an example of an inventory plan created by calculating the inventory amount on each day so as to fall within the range of the upper and lower limit values (that is, to satisfy the above-described constraint conditions) without using the target inventory transition 410. On the other hand, FIG. 9(b) shows an example of an inventory plan created by calculating the inventory amount on each day so that, in addition to the inventory amount on each day falling within the range of the upper and lower limit values, the difference from the target inventory transition 410 becomes small using the above-described evaluation index. The same ones were used as the acquisition plan 510, the usage plan 520, the transportation plan 610, and the estimated receipt 710 to create each inventory plan.

[0083] The inventory plans 901 and 911 are inventory plans for the same steelworks. Similarly, the inventory plans 902 and 912, the inventory plans 903 and 913, the inventory plans 904 and 914, the inventory plans 905 and 915 are inventory plans for the same steelworks respectively. Also, the inventory plans 906 and 916 are inventory plans for all five steelworks.

[0084] As shown in Fig. 9(a), if the target inventory transition 410 described in this embodiment is not used, for example, as shown in the inventory plan 903, the inventory level may become extremely high compared to other steelworks. On the other hand, as shown in Fig. 9(b), by approaching the inventory level to the target inventory transition 410 described in this embodiment, the balance of the inventory levels at each steelworks can be achieved.

[0085] <Summary> As described above, in this embodiment, the processing device 300 calculates the target inventory transition 410 for each of a plurality of customers (Yangang (= steelworks) U) using the acquisition plan 510 and the usage plan 520. In this way, it is possible to calculate the target inventory transition 410 assuming both supply fluctuations and demand fluctuations from the acquisition plan 510 and the usage plan 520. Therefore, it is possible to create an inventory plan with a sufficient margin from the upper and lower limit values, and to calculate the target inventory transition 410 that matches both supply fluctuations and demand fluctuations. Thus, even when there are supply fluctuations in the supply of objects to the customers and demand fluctuations in the demand for objects by the customers, it is possible to calculate the target inventory level that suppresses the excess or deficiency of the inventory level at the customers. As a result, for example, it is possible to create an inventory plan that is robust to supply fluctuations and demand fluctuations.

[0086] Also, in this embodiment, the processing device 300 further calculates the target inventory transition 410 using the distribution ratio of the amount of the object transported by the transportation means (transport ship C) to a plurality of customers (Yangang (= steelworks) U). Therefore, it is possible to quantitatively calculate the supply amount to each customer (Yangang (= steelworks) U).

[0087] In addition, in the present embodiment, the processing device 300 uses, as the allocation ratio, a first allocation ratio based on the planned usage amount of an object (raw material) at each of a plurality of customers (Yangang (= steelworks) U). Therefore, it is possible to calculate the target inventory transition 410 in consideration of the demand prediction of each customer (Yangang (= steelworks) U).

[0088] In addition, in the present embodiment, the processing device 300 uses, as the first allocation ratio, a ratio based on the contemporaneous planned usage amount of an object (raw material) at each of a plurality of customers (Yangang (= steelworks) U). Therefore, for a customer with a large planned usage amount (demand) in each period, the target inventory amount of the customer in that period can be increased, while for a customer with a small planned usage amount (demand), the target inventory amount of the customer in that period can be decreased. Thus, it is possible to reduce the risk that the inventory amount of each customer deviates from the upper and lower limit values while preventing the situation where relatively more objects are allocated to a customer with relatively less demand and relatively fewer objects are allocated to a customer with relatively more demand.

[0089] In addition, in the present embodiment, the processing device 300 uses, as the allocation ratio, a second allocation ratio based on the conveyance order of an object (raw material) when one conveyance means (conveyance ship C) conveys the object to a plurality of customers (Yangang (= steelworks) U). Therefore, it is possible to adjust the target inventory amounts at a plurality of customers (Yangang (= steelworks)) U that receive the supply of an object (raw material) from one conveyance means (conveyance ship C).

[0090] In addition, in the present embodiment, the processing device 300 further uses the estimated incoming amount 710 to calculate the target inventory transition 410. The estimated incoming amount 710 includes information that enables identification of the scheduled arrival time of an object on the customer (Yangang (= steelworks) U) side. Therefore, it is possible to calculate the target inventory transition 410 in consideration of the conveyance time.

[0091] In addition, in the present embodiment, the processing device 300 calculates the target inventory quantity at the time corresponding to the scheduled arrival time of the object specified from the received estimated expectation 710 for each customer (Yanggang (= steelworks) U) based on the planned usage quantity of the object at the time corresponding to the scheduled arrival time. Therefore, the target inventory transition 410 corresponding to the demand at the scheduled arrival time of the object can be calculated.

[0092] In addition, in the present embodiment, the processing device 300 uses a time longer than the unit time of the usage plan 520 as the unit time of the target inventory transition 410. Therefore, it is possible to suppress the calculation of the target inventory transition 410 in which the time transition of the target inventory quantity fluctuates greatly.

[0093] In addition, in the present embodiment, the processing device 300 calculates the target inventory transition 410 using the transportation plan 610 instead of the acquisition plan 510. Therefore, the target inventory transition 410 corresponding to the transportation mode can be calculated, for example, when there are a plurality of transportation means (transport ship C).

[0094] In addition, in the present embodiment, the processing device 300 uses the transportation plan 610 calculated based on the acquisition plan 510. Therefore, it is possible to use the transportation plan 610 corresponding to the acquisition quantity. Thereby, for example, it is possible to suppress the transportation quantity of the transportation plan 610 from becoming excessive or insufficient with respect to the acquisition quantity.

[0095] In addition, in the present embodiment, the processing device 300 uses a plan that can specify the acquisition quantity for each category of the object as the acquisition plan 510. Also, the processing device 300 uses a plan that can specify the usage quantity for each category of the object as the usage plan 520. Then, the processing device calculates the target inventory transition 410 for each of the plurality of customers (Yanggang (= steelworks) U) for each category of the object. Therefore, the target inventory transition 410 can be calculated for each category (for example, type) of the object.

[0096] (Other embodiments) Note that the embodiments of the present invention described above can be realized by a computer executing a program. Also, a computer-readable recording medium recording the program and a computer program product such as the program can also be applied as embodiments of the present invention. As the recording medium, for example, a flexible disk, a hard disk, an optical disk, a magneto-optical disk, a CD-ROM, a magnetic tape, a non-volatile memory card, a ROM, etc. can be used. Further, the embodiments of the present invention may be realized by a PLC (Programmable Logic Controller) or may be realized by dedicated hardware such as an ASIC (Application Specific Integrated Circuit). Also, the embodiments of the present invention described above are merely examples of specific implementations in carrying out the present invention, and the technical scope of the present invention should not be construed in a limited manner by these. That is, the present invention can be implemented in various forms without departing from its technical idea or its main features.

[0097] Note that the disclosure of the above embodiments is as follows, for example. [Disclosure 1] A processing device that performs a process of calculating a target inventory trend indicating the time change of the target inventory quantity of an object at a customer, comprising a target inventory trend calculation unit that calculates the target inventory trend for each of the plurality of customers using an acquisition plan indicating the time change of the estimated quantity of the object to be obtained at the supplier of the object and a usage plan indicating the time change of the estimated quantity of use of the object at each of the plurality of customers. [Disclosure 2] The processing device according to Disclosure 1, wherein the target inventory trend calculation unit calculates the target inventory trend using, in addition, a distribution ratio of the quantity of the object transported by the transport means to the plurality of customers. [Disclosure 3] The processing device according to Disclosure 2, wherein the distribution ratio includes a first distribution ratio based on the estimated quantity of use of each of the plurality of customers. [Disclosure 4] The processing apparatus according to Disclosure 3, wherein the first allocation ratio includes a ratio based on the usage prediction amounts at the same time in each of the plurality of customers. [Disclosure 5] The processing apparatus according to any one of Disclosures 2 to 4, wherein the allocation ratio includes a second allocation ratio based on the order of transporting the object when one transport means transports the object to the plurality of customers. [Disclosure 6] The processing apparatus according to any one of Disclosures 1 to 5, wherein the target inventory trend calculation unit calculates the target inventory trend by further using a reception estimate including information capable of specifying the scheduled arrival time of the object on the customer side. [Disclosure 7] The processing apparatus according to Disclosure 6, wherein the target inventory trend calculation unit calculates the target inventory amount at the time corresponding to the scheduled arrival time of the object based on the usage prediction amount at the time corresponding to the scheduled arrival time of the object. [Disclosure 8] The target inventory trend indicates the target inventory amount of the object per unit time at the customer, The acquisition plan indicates the estimated acquisition amount per unit time of the object at the supplier of the object, The usage plan indicates the usage prediction amount of the object in each of the plurality of customers. The unit time of the target inventory trend is longer than the unit time of the usage plan. The processing apparatus according to Disclosure 7. [Disclosure 9] The processing apparatus according to any one of Disclosures 1 to 8, wherein the target inventory trend calculation unit calculates the target inventory trend by using the transportation plan of the object by the transport means in addition to or instead of the acquisition plan. [Disclosure 10] The processing apparatus according to Disclosure 9, wherein the transportation plan is calculated based on the acquisition plan. [Disclosure 11] The processing apparatus according to any one of Disclosures 1 to 10, wherein the acquisition plan is an acquisition plan for each of the plurality of suppliers. [Disclosure 12] The acquisition plan is a plan capable of specifying the estimated acquisition amount for each category of the object, The usage plan is a plan capable of specifying the planned usage quantity for each category of the object. The target inventory trend calculation unit is a processing device according to any one of Disclosures 1 to 11, which calculates the target inventory trend for each of a plurality of customers for each category of the object. [Disclosure 13] The processing device according to any one of Disclosures 1 to 12, further comprising a plan creation unit that creates an inventory plan showing the time transition of the planned value of the inventory quantity of the object for the customer based on the target inventory trend. [Disclosure 14] The target inventory trend indicates the target inventory quantity of the object for each unit time at the customer. The acquisition plan indicates the planned acquisition quantity per unit time of the object at the supplier of the object. The usage plan indicates the planned usage quantity of the object for each of a plurality of customers, and is a processing device according to any one of Disclosures 1 to 13. [Disclosure 15] A processing method for performing a process of calculating a target inventory trend indicating the target inventory quantity of an object at a customer, comprising: a target inventory trend calculation step of calculating the target inventory trend for each of a plurality of customers using an acquisition plan showing the time transition of the planned acquisition quantity of the object at the supplier of the object and a usage plan showing the time transition of the planned usage quantity of the object for each of a plurality of customers. [Disclosure 16] A program for causing a computer to function as the function of the target inventory trend calculation unit of the processing device according to any one of Disclosures 1 to 14.

Explanation of Signs

[0098] 101a~101b Inventory plan considering only upper and lower limits 102a~102c Upper limit value of inventory quantity 103a~103c Lower limit value of inventory quantity 201a~201c Inventory plan considering target inventory trend 300 Processing device 301 Input device 302 Output device 310 Target inventory trend calculation unit 320 Planning generation unit 330 Output unit 410a~410b Target inventory trend 510 Acquisition plan 520 Usage plan 610, 620 Transportation plan 710 Receiving estimate 901~906 Calculation results of inventory plan considering only upper and lower limits 911~916 Calculation results of inventory plan considering target inventory trend N1 Stock P1, P2, Pn Port of loading U1, U2 Port of unloading S 01 , S 02 Initial value of target inventory level t 11 , t 12 At departure (scheduled departure date) t 21 ~t 27 Year and month of each unit time of target inventory trend t 31 , t 32 At arrival (scheduled arrival date) t s First year and month of the calculation target period of target inventory trend t e Last year and month of the calculation target period of target inventory trend ΔT1 Unit time of target inventory trend

Claims

1. A processing device that performs a process of calculating a target inventory trend indicating the time change of the target inventory quantity of an object at a customer's home, comprising a target inventory trend calculation unit that calculates the target inventory trend for each of the plurality of customers using a procurement plan indicating the time change of the estimated quantity of the object to be obtained at the supplier of the object and a usage plan indicating the time change of the estimated quantity of use of the object at each of the plurality of customers.

2. The processing device according to claim 1, wherein the target inventory trend calculation unit calculates the target inventory trend using, in addition, a distribution ratio of the quantity of the object transported by the transportation means to the plurality of customers.

3. The processing device according to claim 2, wherein the distribution ratio includes a first distribution ratio based on the estimated quantity of use of each of the plurality of customers.

4. The processing device according to claim 3, wherein the first distribution ratio includes a ratio based on the estimated quantity of use at the same time period for each of the plurality of customers.

5. The processing device according to any one of claims 2 to 4, wherein the distribution ratio includes a second distribution ratio based on the order of transportation of the object when one transportation means transports the object to the plurality of customers.

6. The processing device according to any one of claims 1 to 4, wherein the target inventory trend calculation unit further calculates the target inventory trend using a receiving estimate including information capable of specifying the scheduled arrival time of the object on the customer side.

7. The processing device according to claim 6, wherein the target inventory trend calculation unit calculates the target inventory quantity at the time corresponding to the scheduled arrival time based on the estimated quantity of use at the time corresponding to the scheduled arrival time of the object.

8. The target inventory trend indicates the target inventory quantity of the object per unit time at the customer, the procurement plan indicates the estimated quantity of procurement per unit time of the object at the supplier of the object, the usage plan indicates the estimated quantity of use of the object at each of the plurality of customers, and the unit time of the target inventory trend is longer than the unit time of the usage plan. The processing device according to claim 7.

9. The processing device according to any one of claims 1 to 4, wherein the target inventory trend calculation unit calculates the target inventory trend using, in addition to or instead of the procurement plan, a transportation plan of the object by a transportation means.

10. The processing device according to claim 9, wherein the transportation plan is calculated based on the procurement plan.

11. The acquisition plan is an acquisition plan for each of the plurality of suppliers, the processing apparatus according to any one of claims 1 to 4.

12. The acquisition plan is a plan capable of specifying the planned acquisition quantity for each category of the object, The usage plan is a plan capable of specifying the planned usage quantity for each category of the object, The target inventory trend calculation unit calculates the target inventory trend for each of the plurality of customers for each category of the object, the processing apparatus according to any one of claims 1 to 4.

13. The processing apparatus according to any one of claims 1 to 4, further comprising a plan creation unit that creates an inventory plan indicating the time transition of the planned value of the inventory quantity of the object at the customer based on the target inventory trend.

14. The target inventory trend indicates the target inventory quantity of the object for each unit time at the customer, The acquisition plan indicates the planned acquisition quantity of the object for each unit time at the supplier of the object, The usage plan indicates the planned usage quantity of the object for each of the plurality of customers, the processing apparatus according to any one of claims 1 to 4.

15. A processing method for performing a process of calculating a target inventory trend indicating the target inventory quantity of an object at a customer, The method includes a target inventory trend calculation step of calculating the target inventory trend for each of the plurality of customers by using an acquisition plan indicating the time transition of the planned acquisition quantity of the object at the supplier of the object and a usage plan indicating the time transition of the planned usage quantity of the object for each of the plurality of customers.

16. A program for causing a computer to function as the function of the target inventory trend calculation unit of the processing apparatus according to any one of claims 1 to 4.

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