JP7077782B2 - Yard management equipment, yard management methods, and programs - Google Patents

Description

The present invention relates to a yard management device, a yard management method, and a program, and in a metal manufacturing process, a pile of metal materials is sorted in a yard provided for smoothly supplying metal materials such as slabs and coils to the next process. It is suitable to be used for this purpose.

In the iron-making process, which is an example of the metal manufacturing process, when the steel material, which is an example of the metal material, is transported from the steel-making process to the rolling process of the next process, the steel material is once placed in a temporary storage place called a yard and then placed in a temporary storage place. It is carried out from the yard according to the processing time of the rolling process, which is the next process. An example of the layout of the yard is shown in FIG. As shown in FIG. 8, the yard is a storage space 801 to 804 partitioned vertically and horizontally as a buffer area for supplying a steel material such as a slab discharged from the upstream process to the downstream process. The vertical divisions are often referred to as "buildings" and the horizontal divisions are often referred to as "columns". That is, the cranes (1A, 1B, 2A, 2B) can move in the building and transfer steel materials between different rows in the same building. In addition, steel materials will be transferred between buildings using a transfer table. When creating a transport command, the "building" and "row" are specified to indicate where to transport the steel material (numbers (11) in parentheses in the storage areas 801 to 804 in FIG. 8). (12), (21), (22)).

Next, the basic work flow in the yard is shown by taking FIG. 8 as an example. First, the steel material carried out from the continuous casting machine 810 in the steelmaking process, which is the previous process, is carried to the yard by the receiving table X via the piler 811 and is partitioned by the cranes 1A, 1B, 2A and 2B. It is transported to any of ~ 804 and piled up. Then, it is placed on the payout table Z again by the cranes 1A, 1B, 2A, and 2B according to the manufacturing schedule of the rolling process, which is a subsequent process, and is conveyed to the rolling process. Generally, steel materials are placed in a pile as described above in a yard. This is to make effective use of the limited yard area.
In the present specification, claims, and drawings, "already arrived mountain", "virtual mountain", "initial mountain", "final mountain", and "temporary mountain" are used with the following meanings.
Already arrived mountain: A mountain that has already been formed in the yard at this time.
Virtual mountain: A mountain (not a mountain that actually exists) assuming that metal materials that have not arrived at the yard at this time are piled up in the order of arrival at the yard.
Early mountain: A general term for existing mountains and virtual mountains.
Final mountain: The final mountain (also called the payout mountain) that is piled up to be paid out for the post-process.
Temporary mountain: A mountain that is unavoidably temporarily placed when transferring from the initial mountain to the final mountain after the present time.

In the yard, in order to reduce the fuel intensity of the heating furnace in the hot rolling process, which is the next process, it is required that the steel material be charged into the heating furnace while maintaining the temperature as high as possible. For this reason, heat insulation equipment may be installed in the yard these days, and steel materials may be stored in piles. In order to effectively utilize the limited heat insulation equipment, it is necessary to stack steel materials as high as possible. On the other hand, when stacking steel materials, the steel materials are stacked from the top in the processing order in the next process in the final pile so that they can be easily supplied to the next process, and the stacking shape of the final pile is not an unstable inverted pyramid shape. There are restrictions such as things (this is called "stacking constraint"). Furthermore, the workload when setting up a mountain (creating the final mountain) is also an element that cannot be overlooked. Therefore, in yard control, it is desirable to formulate a work plan for raising the final mountain as high as possible with as little workload as possible under the above-mentioned stacking restrictions.

In addition, when performing mountain sorting (dividing steel materials into multiple piles) to smoothly pay out the steel materials required for the post-process in the yard, the steel materials scheduled to arrive will be demoted (steel materials are built in). Due to quality problems that occur at the time, the grade is lowered from the originally planned use and transferred to another use), or the steel material to be arrived requires unplanned scouring, or the size changes. By doing so, it can often happen that the steel material does not arrive as originally planned. In addition, it can hardly be expected that the state of the yard will change as originally planned, and it is a daily occurrence that unplanned steel materials have to be placed in unplanned yard.

Furthermore, the rolling order of the steel materials piled up in the pile in the order of delivery from the yard to the hot rolling process, which is the post-process, in the hot rolling process, which is the post-process, will be changed after the steel materials arrive at the yard. As a result, the piles are no longer stacked in the payout order, and it is often the case that the steel materials are forced to be reloaded according to the changed rolling order. Here, the fact that steel materials are piled up in a pile in the order of discharge means that one or a plurality of steel materials that are relatively above and simultaneously transported are below the steel material at any stacking position of the pile. It means that it is paid out to the post-process earlier than a certain steel material.

However, the transshipment work required here must be performed in parallel with the work of receiving the steel material into the yard and the work of discharging the steel material from the yard. Storage space is limited. Therefore, it is required to efficiently and space-saving transshipment work of steel materials.
Therefore, due to various circumstances before and after arriving at the yard, the work of transshipping the piles that are no longer in the payout order at the time of arrival at the yard can be efficiently (that is, with as few transports as possible) and as few finals as possible. There is an extremely high need to keep the number of mountains and to keep them in as few temporary storage areas as possible.

There are inventions described in Patent Documents 1 to 3 as a conventional technique for transshipping a steel material from an initial pile to a final pile as described above.
First, in Patent Document 1, when transshipping the steel materials of the already arrived mountain already in the yard in the order of payout, the optimum mountain shape of the final mountain is combined and optimized in consideration of the necessary transfer load and stacking shape restrictions. A method of formulating as a combinatorial problem and calculating using a tabu search method is disclosed. However, in the invention described in Patent Document 1, although the method of obtaining the mountain shape of the final mountain is shown, the point of how to obtain the transportation order from the initial mountain to the final mountain is clearly shown. Not.

Next, in Patent Document 2, in the situation where steel materials that have arrived at the yard and materials that have not arrived are mixed, the initial mountain state and the final mountain state at that time are given. For the problem of transshipment and transfer of steel materials from the state of It has been disclosed.
Finally, Patent Document 3 discloses a method of simultaneously optimizing the mountain sorting and the transport order by reducing the result to a mathematical planning problem that satisfies the constraint conditions relating to the pile standing and the transport.

Japanese Patent No. 4935032 Japanese Patent No. 5365759 Japanese Patent No. 5434267 Japanese Unexamined Patent Publication No. 2016-81186 Japanese Unexamined Patent Publication No. 2007-84201

However, in the techniques described in Patent Documents 1 to 3, when transshipment of a mountain, a problem is set on the premise that all the steel materials are moved or the steel materials that do not move (fix) are given in advance.

When transshipping mountains that are already piled up in the yard, in actual operation, unless there is a request to change the mountain yard itself, you can do it instead of transshipping the mountains by moving them together for each mountain. In order to reduce the number of transshipments, a method of avoiding unnecessary movement of steel materials is adopted. That is, in the case of such transshipment, it is required to transship the steel material that does not need to be moved in the initial pile with the minimum number of transports as it is. To achieve this, it is not always the best way to prevent all steel materials that can be non-moving (fixed) from moving. This is because there may be a case where the number of final peaks increases because the steel material that can be non-moving (fixed) is not moved. Therefore, if the pros and cons of moving the steel material for minimizing the number of peaks of the final peak are not taken into consideration as in the techniques described in Patent Documents 1 to 3, the number of peaks of the final peak may increase.

The present invention has been made in view of the above problems, and when creating a transfer plan for metal materials for transshipping metal materials from the initial mountain to the final mountain, the total number of final mountains is the minimum. It is an object of the present invention to be able to distinguish between a metal material that should be moved and a metal material that should not be moved so that the number of metal materials that move is minimized.

The yard management device of the present invention transports the metal material of the initial pile made of metal material piled up in the yard, which is a storage place between processes, by a transport device, and stacks the metal material according to the delivery order to the subsequent process of the yard. When creating a final pile made of metal materials that are piled up in order, a moving metal material that is a metal material transported from the initial pile to the final pile at the yard and the final pile in the same place as the initial pile. A yard management device for determining a non-moving metal material to be fixed at the location of the initial mountain in order to create the initial mountain, and the metal material constituting the initial mountain is the non-moving metal material in the initial mountain. A determination variable is a non-moving uppermost metal material discriminating variable indicating whether or not the metal material is the uppermost metal material, and a moving presence / absence discriminating variable indicating whether or not the metal material is a moving metal material. The final integer value is equal to or greater than the value obtained by dividing the total number of the metal materials constituting the initial mountain by the height upper limit value which is the upper limit of the number of the metal materials constituting the final mountain. Metallic material information acquisition means for acquiring metal material information including the identification information of the initial mountain, the identification information of the metal material at each stacking position of the initial mountain, and the payout order of the metal material as the total number of mountains. And, when all the payout orders are set, the number of the moving metal materials that is the payout order before the payout order that the payout order is arbitrarily set is the payout order before the payout order that the payout order is arbitrarily set. In a constraint equation using the determination variable, it is necessary to have more than the number of moving metal materials that can be stacked on the non-moving metal material at the uppermost stage among the non-moving metal materials. A constraint expression setting means for setting a constraint expression including a certain transshipment constraint expression based on the metal material information, an objective function for the purpose of minimizing the total number of the moving metal materials, or the non-moving metal material. When the value of the objective function becomes the minimum or the maximum within the range satisfying the constraint expression and the objective function setting means for setting the objective function for the purpose of maximizing the total number of It is characterized by having an optimization calculation means for deriving the value of the determination variable of the above as an optimum solution by performing an optimization calculation by a mathematical programming method.

In the yard management method of the present invention, the metal material of the initial pile made of metal material piled up in the yard, which is a storage place between processes, is conveyed by a transport device, and the yard is stacked according to the order of delivery to the subsequent process. When creating a final pile made of metal materials that are piled up in order, a moving metal material that is a metal material transported from the initial pile to the final pile at the yard and the final pile in the same place as the initial pile. It is a yard management method for determining a non-moving metal material fixed to the place of the initial mountain in order to create the initial mountain, and the metal material constituting the initial mountain is the non-moving metal material in the initial mountain. A determination variable is a non-moving uppermost metal material discriminating variable indicating whether or not the metal material is the uppermost metal material, and a moving presence / absence discriminating variable indicating whether or not the metal material is a moving metal material. The final integer value is equal to or greater than the value obtained by dividing the total number of the metal materials constituting the initial mountain by the height upper limit value which is the upper limit of the number of the metal materials constituting the final mountain. The metal material information acquisition step of acquiring the metal material information including the identification information of the initial mountain, the identification information of the metal material at each stacking position of the initial mountain, and the payout order of the metal material as the total number of mountains. And, when all the payout orders are set, the number of the moving metal materials that is the payout order before the payout order that the payout order is arbitrarily set is the payout order before the payout order that the payout order is arbitrarily set. In a constraint equation using the determination variable, it is necessary to have more than the number of moving metal materials that can be stacked on the non-moving metal material at the uppermost stage among the non-moving metal materials. A constraint expression setting step for setting a constraint expression including a transshipment constraint expression based on the metal material information, an objective function for the purpose of minimizing the total number of the moving metal materials, or the non-moving metal material. When the objective function setting step for setting the objective function for the purpose of maximizing the total number of the metal materials and the value of the objective function becomes the minimum or the maximum within the range satisfying the constraint equation. It is characterized by having an optimization calculation step of deriving the value of the determination variable of the above as an optimum solution by performing an optimization calculation by a mathematical programming method.

The program of the present invention is characterized in that a computer functions as each means of the yard management device.

According to the present invention, when creating a transport plan for metal materials for transshipping metal materials from the initial mountain to the final mountain, the number of metal materials to be moved is the minimum within the range where the number of mountains in the final mountain is the minimum. Therefore, it is possible to distinguish between a metal material that should be moved and a metal material that should not be moved.

FIG. 1 is a diagram showing an example of a functional configuration of a yard management device. FIG. 2 is a flowchart illustrating an example of a yard management method. FIG. 3 is a diagram showing an example of a list of steel materials to be transshipped. FIG. 4 is a diagram showing an example of a calculation result by the method of the present embodiment. FIG. 5 is a diagram showing a first example of a calculation result when the total number of final peaks is allowed to be larger than the number obtained by the method of the present embodiment. FIG. 6 is a diagram showing a first example of a calculation result when the total number of final peaks is allowed to be larger than the number obtained by the method of the present embodiment. FIG. 7 is a diagram showing an example of calculation results by the method of the present embodiment when various data in actual operation are used. FIG. 8 is a diagram showing an example of a yard layout.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the present embodiment, in the steel manufacturing process, given the mountain shape of the initial mountain, it should be moved (transported) from the steel material constituting the initial mountain under the premise that the number of the final mountain is minimized. Determine the steel material and the steel material that should not be moved (transported). Then, assuming that only the steel material to be moved is moved, the mountain shape of the final mountain and the transport order of each steel material when transporting from the initial mountain to the final mountain are derived by a known method. It is assumed that the steel materials (slabs) manufactured in the steelmaking process are not stacked in the order of transportation to the rolling process in at least a part of the initial pile. Further, in the following description, the order of transporting each steel material to the rolling process is referred to as the payout order as necessary. Further, the steel material determined to be moving according to the present invention is referred to as a moving steel material as necessary, and the steel material determined not to be moved is referred to as a non-moving steel material as necessary. Further, in the following description, "moving steel material" and "non-moving steel material" may be referred to as "moving steel material" and "non-moving steel material", respectively.

First, the points to be focused on when realizing the present embodiment will be described.
Consider the problem of maximizing the total number of non-moving steel materials on the premise that the total number of final peaks will be minimized. Here, all steel materials can be identified as either mobile steel materials or non-moving steel materials.
Further, the steel material that can be a non-moving steel material can be determined from the mountain shape of the initial mountain. The steel material that can be a non-moving steel material is the part where the stacking order from the bottom of the initial pile is the payout order (the payout order is descending from the bottom to the top). In addition, if a certain steel material is a non-moving steel material in each initial mountain, the steel material group under it must also be a non-moving steel material. This is because in order to move the group of steel materials below the non-moving steel material, the non-moving steel material must be moved. Therefore, among the non-moving steel materials in each initial pile, all the steel materials above the non-moving steel material at the uppermost stage are mobile steel materials.

(Assumption of problem)
In the present embodiment, the mountain shape of the initial mountain and the payout order (rolling order) of each steel material are given.
Here, the set of steel material groups is expressed as N = {1, 2, ..., _ng }. The steel material group refers to a group of one or more steel materials that are not divided (the minimum unit) when transported by a transport device (mainly a crane). Therefore, in the present embodiment, the case where the movement (transportation) of the steel material is performed in the unit of the steel material group will be described as a basis. Therefore, the steel group determined to be moving according to the present invention is referred to as a moving steel group as necessary, and the steel group determined not to be moved is referred to as a non-moving steel group as necessary. However, for the sake of brevity, the "moving steel material group" and "non-moving steel material group" may be simply referred to as "moving steel material" and "non-moving steel material", respectively. Further, when the movement (transportation) of the steel material is performed in units of one steel material, the "steel material group" may be read as "steel material" in the following description.

As mentioned above, the initial mountains include existing mountains and virtual mountains. The existing mountain is a mountain that is piled up in the yard at the time when the steel material information is created (that is, when the final mountain is created) among the steel materials to be created as the final mountain. In the virtual mountain, among the steel materials for which the final mountain is to be created, the steel materials that have not yet been piled up in the yard at the time when the steel material information is created (that is, when the final mountain is created) are scheduled to arrive at the yard in the order of arrival. It is a mountain when it is assumed that the earlier ones are piled up. In the present embodiment, among the steel materials for which the final pile is to be created, all the steel materials that have not arrived at the yard and have not yet been piled up are piled up in one virtual pile. As described above, in the present embodiment, it is assumed that the steel materials that have not arrived at the yard and have not been piled up are also piled up as virtual piles (that is, all the steel materials for which the final pile is to be created are piled up in the yard. ), Given that stack. As for the steel materials (non-arrival materials) that make up the virtual pile, it is assumed that there are no non-moving steel materials, and all of them are mobile steel materials. Therefore, the steel material constituting the virtual crest is treated as a moving steel material when determining either the moving steel material or the non-moving steel material.

The shape of the initial mountain is known, but the shape of the final mountain is unknown. The final mountain shall be the mountain piled up in the order of payout from the top. In addition, if there is a steel material that can be piled up in the final pile, the steel material shall be piled up to the limit of the height limit. Therefore, assuming that the upper limit of the height of the final mountain is h, the total number z of the final mountain is expressed by the following equation (1). Here, n represents the total number of steel materials. In this way, the total number z of the final mountains is the minimum number determined by the height limit.

The upper limit h of the height of the final mountain shall be represented by the number of steel materials that can be loaded as the final mountain. Further, in the equation (1), ceil (n / h) represents a ceiling function (minimum integer value of n / h or more).
When maximizing the total number of non-moving steel materials, the non-moving steel materials may become trivial without the assumption of Eq. (1). However, by making the assumption of Eq. (1), even in the steel group where the stacking order from the bottom of the initial pile is the payout order (the payout order is descending from the bottom to the top), the final pile. In some cases, it becomes a moving steel material in order to increase the height of the material.

In addition, the maximum number of transports from the initial mountain (initial storage area) to the final mountain (final storage area) is 2 for any steel group. That is, the steel material group transported twice will be temporarily placed, but the steel material group transported to the temporary mountain (temporary storage site) shall be transported to the final mountain (final storage site) at the next transportation. It shall not be transported between different temporary mountains (temporary storage areas).
In addition, the place where the initial mountain with the non-moving steel material is located becomes the place where the final mountain containing the non-moving steel material is placed. The final pile composed only of the moving steel material will be placed in a different storage place from the initial pile containing the moving steel material unless all of the moving steel material is temporarily placed. On the other hand, even if the final pile is composed only of the moving steel material, if a part of the moving steel material is temporarily placed and is transported again to the initial pile where the temporarily placed moving steel material was, the final pile is , It will be placed in the same place as the initial mountain place of the moving steel material.

Further, in the present embodiment, the following width constraint, length constraint, and height constraint are used as stacking constraints.
Width constraint If the maximum width of a steel group is narrower than the minimum width of a steel group located below the steel group, then the steel group is placed above the steel group located below it. Can be placed unconditionally. When the maximum width of a certain steel group is wider than the minimum width of the steel group located below the certain steel group, the difference between the two widths is a reference value determined by work constraints (for example, 200 [mm]). ), The certain steel group can be placed on the steel group located below the steel group, but cannot be placed beyond the steel group.

That is, the width constraint is satisfied when the maximum width of a certain steel group is narrower than the minimum width of the steel group located below the certain steel group, and when the maximum width of the certain steel group is the said. This is a case where the width is wider than the minimum width of the steel material group located below the steel material group and the difference between the widths is less than the reference value (for example, 200 [mm]).

-Length constraint If the maximum length of a steel group is shorter than the minimum length of a steel group located below the steel group, the steel group is placed above the steel group located below the steel group. Can be placed unconditionally. When the maximum length of a certain steel group is longer than the minimum length of the steel group located below the certain steel group, the difference in length between the two is a reference value determined by work constraints (for example, 2000 [mm]). ]) If it is less than, the certain steel group can be placed on the steel group located below, but if it exceeds it, it cannot be placed.

That is, the length constraint is satisfied when the maximum length of a certain steel material group is shorter than the minimum length of the steel material group located below the certain steel material group, and when the maximum length of the certain steel material group is the said. This is a case where the length is longer than the minimum length of the steel material group located below a certain steel material group, and the difference in length between the two is less than the reference value (for example, 2000 [mm]).

-Height constraint The number of steel materials that can be piled up as one final pile must be less than or equal to the upper limit of the height of the final pile h. The upper limit h of the height of the final mountain is, for example, 10.

(Coefficient of determination)
<Coefficient of determination used when determining non-moving steel and moving steel>
In the present embodiment, the non-moving uppermost stage steel material discriminating variable x _i and the moving presence / absence discriminating variable y _i are set as determining variables for any steel material group i. The non-moving uppermost steel material discriminating variable x _i is defined as the following equation (2), and the moving presence / absence discrimination variable y _i is defined as the following equation (3).

The non-moving top-stage steel material discriminant variable x _i is 1 when the steel material group i constituting a certain initial mountain is the non-moving steel material group at the top of the non-moving steel material group, and 0 (otherwise). It is a 0-1 variable that becomes zero). As described above, if there is no non-moving steel material group in the initial pile, the non-moving uppermost steel material discriminating variable x _i for all the steel material groups i constituting the initial pile becomes 0 (zero). On the other hand, if there is one or more non-moving steel material groups in the initial pile, only the non-moving uppermost stage steel material discriminating variable x _i with respect to the non-moving steel material group i at the uppermost stage of the non-moving steel material group becomes 1. In this case, the non-moving uppermost steel material discriminating variable x _i with respect to the other steel material groups i constituting the initial pile becomes 0 (zero) (even if the steel material group i is the non-moving steel material group). That is, for one initial pile, the maximum number of steel material groups in which the non-moving uppermost steel material discriminant variable x _i is 1.
The movement presence / absence discriminant variable y _i is a 0-1 variable that becomes 1 when the steel material group i is a moving steel material group and 0 (zero) when the steel material group i is not.

<Determining variables used to determine the order of transportation and the shape of the final mountain>
In the present embodiment, after the non-moving steel group and the moving steel group are determined, only the moving steel group is moved (transported), and the transport order and final of each steel group i when transshipping from the initial pile to the final pile. Determine the mountain appearance of the mountain. A method for determining the transport order of each steel group i and the shape of the final mountain when transshipping from the initial mountain to the final mountain can be realized by a known technique. In this embodiment, a case where the method described in Patent Document 3 is used will be described as an example. In Patent Document 3, the mountain sorting / transporting order variable x [i] [m] [s], the temporary placement determination variable y [p] [s ₁ ] [s ₂ ], and the optimum mountain existence determination variable δ [m]. Is the determinant. Since the details of these decision variables are described in Patent Document 3, the detailed description thereof will be omitted here, and only the outline will be described.

The mountain sorting / transport order variable x [i] [m] [s] is 1 when the steel group i is transported to the final pile m (m: final pile ID) in the transport order s, and 0 (otherwise). It is a 0-1 variable that becomes zero). The temporary placement determination variable y [p] [s ₁ ] [s ₂ ] is used when the pair p of the steel material groups stacked vertically adjacent to each other in the initial pile is transported in the order of transport order s ₁ and s ₂ . It is a 0-1 variable that becomes 0 (zero) if it is not 1. The optimum mountain existence determination variable δ [m] is a 0-1 variable that becomes 1 when the final mountain m exists and 0 (zero) when the final mountain m does not exist.

(Functional configuration of yard management device 100)
FIG. 1 is a diagram showing an example of a functional configuration of the yard management device 100. The hardware of the yard management device 100 is realized by using, for example, a CPU, a ROM, a RAM, an HDD, an information processing device having various interfaces, or dedicated hardware. FIG. 2 is a flowchart illustrating an example of a yard management method executed by the yard management device 100.
[Steel Material Information Acquisition Unit 101, Steel Material Information Acquisition Step S201]
The steel material information acquisition unit 101 acquires steel material information about the steel material to be piled up. The steel material information includes information on the steel material group, information on specifying the mountain shape of the initial mountain of each steel material group, and information on specifying the upper limit value h of the height of the final mountain.

The steel group information includes identification information, payout order, and number of steel materials for each of the steel material groups (set N = {1, 2, ..., _ng }) for which the final pile is to be created. , Maximum width, minimum width, maximum length, and minimum length information is included. The steel material group refers to a group of steel materials that are not divided (the smallest unit) when transported by a transport device (mainly a crane). Here, for the sake of simplicity, it is assumed that all the steel materials have the same thickness.
The identification information is identification information (steel material group ID) that uniquely identifies each steel material group.
The payout order is the payout order (transportation order to the rolling process) of each steel material group. In this embodiment, since the identification information is in the payout order, the payout order does not have to be included in the steel material group information.

The number of steel materials ( _wi : N → Z +) is the number of steel materials constituting each steel material group. The number w _i of the steel materials included in one steel material group is, for example, 1 or more and 6 or less (∀i ∈ N, 1 ≦ w _i ≦ 6). As described above, the steel material group may include not only a plurality of steel materials but also only one steel material.
The maximum width and the minimum width are the maximum width and the minimum width of the steel materials constituting each steel material group, respectively.
The maximum length and the minimum length are the maximum length and the minimum length of the steel materials constituting each steel material group, respectively. Further, the total number of steel materials n shall be represented by the following equation (4).

The information for identifying the mountain shape of the initial mountain includes an initial mountain ID which is identification information uniquely identifying the initial mountain, and a steel material group ID located in each stack of the initial mountain identified by the initial mountain ID. ..
The upper limit h of the height of the final pile is the upper limit of the number of steel materials that can be piled up as one final pile.

When transporting all the steel materials for which the final pile is to be created one by one, the identification information (steel material ID), payout order, width, and length information for each steel material is used instead of the steel material group information. To be acquired. In addition, as information for identifying the mountain shape of the initial mountain, identification information of the initial mountain (initial mountain ID) is acquired, and each product of the initial mountain is used instead of the steel group ID located in each stack of the initial mountain. The steel material ID located in the step is acquired.
Examples of the form of acquiring steel material information include an input operation of the user interface of the yard management device 100, transmission from an external device, and reading from a portable storage medium.

[Constraint expression / objective function setting unit 102, constraint expression setting step S202, objective function setting step S203]
The constraint expression / objective function setting unit 102 sets a constraint expression in which the above-mentioned constraint is expressed by a mathematical formula and an objective function in which the above-mentioned purpose is expressed by a mathematical expression.
<< Constraint expression >>
First, the constraint expression will be described.
There is a steel material group i in which the non-moving top-stage steel material discrimination variable x _i and the movable / non-movable / non-movable variable y _i defined by the equations (2) and (3) can be determined in advance by the mountain shape of a given initial mountain. .. Further, the non-movable uppermost steel material discriminant variable x _i and the moveable / non-movable discriminant variable y _i are dependent on each other. From the above, in the present embodiment, the constraint equations (Equations (7) to (11)) that define each of the non-movable uppermost stage steel material discriminant variable x _i and the movable top stage discriminant variable y _i , and the non-movable uppermost stage. The constraint equations (Equations (12) to (15)) that define the relationship between the steel material discriminant variable x _i and the moveability discriminant variable y _i are used.

(A) Restrictions on moving steel materials Here, the set of the subset Sk ( _⊂N ) of the steel material group obtained by dividing the set N of the steel material group is set to S = {S ₁ , S ₂ , ..., S _r }. write. Each of the subsets _Sk of this steel group is the initial peak. Further, it is assumed that the variable i for identifying the steel material group is numbered in the payout order of the steel material group (the value of the variable i is smaller as the payout order is earlier). Therefore, the following equations (5) and (6) are established.

In each initial mountain _Sk , the partial mountain obtained by extracting the part of all the steel material groups whose product order is the payout order from the bottom (the payout order is descending from the bottom to the top) from the initial mountain _Sk . Let be max (S _k ). A partial mountain here is a mountain composed of a certain steel group of a given mountain and all the steel groups below it, stacked in the same order as the given mountain. At this time, the steel material group that is not in max (S _k ) is always a mobile steel material group. This is expressed by the following equations (7) and (8).

Equation (7) indicates that the steel material group i in the portion _{where max (S k )} is excluded from the initial mountain Sk is moved (becomes a moving steel material group). In equation (8), the steel material group i in the portion _{where max (S k )} is removed from the initial mountain Sk is not the steel group at the top of the non-moving steel group in the initial mountain _Sk . Represents that. According to the equations (7) and (8), the steel group _i whose product order is not in the payout order (the payout order is descending from the bottom to the top) from the bottom in each initial mountain Sk is to move. Is represented.

(B) Restrictions on the non-moving top-stage steel material discrimination variable x _i In each initial mountain Sk, the maximum value of the number of steel material groups _i in which the non-moving top-stage steel material discrimination variable x _i is 1 (x _i = 1) is 1. Is. Therefore, the following equation (9) holds.

Further, the number of initial peaks having the non-moving steel group i cannot exceed the total number z of the final peaks. Therefore, the following equation (10) holds.

(C) Constraints on the variable y _i for determining whether or not to move In each initial mountain Sk, all steel groups above the moving steel group _i move. Therefore, if the payout order (= i (identification number of the steel material group)) when viewed from the bottom to the top of each initial mountain Sk is _{k 1} , k ₂ , ..., The following (11) ) Formula holds.

(D) Constraints that define the relationship between the non-moving top-stage steel material discrimination variable x _i and the movement presence / absence discrimination variable y _i All steel material groups i are uniquely identified as either a moving steel material group or a non-moving steel material group. .. In the initial mountain Sk, if the number of stacked stages (including the steel material and the number of steel materials below it ₎ when counting from the bottom of the steel material at the top of the steel material group _i is bi, the non-moving steel material The total number of groups can be expressed as Σ i _{∈ N} b _i · x _i using the non-moving top steel discriminant variable x _i . Further, the total number of moving steel materials can be expressed as Σ i _{∈ N} y _i · w _i by using the moving presence / absence discriminant variable y _i . Therefore, the following equation (12) is established, which indicates that the sum of the total number of non-moving steel materials and the total number of moving steel materials is the total number of steel materials constituting the initial peaks (already landed peaks and virtual peaks).

If the variable y _i for determining whether or not to move with respect to the steel material group i is 1 (y _i = 1), the non-moving uppermost steel material is discriminated for all of the steel material group i and the steel material group _i above it in the initial mountain Sk. The variable x _i becomes 0 (zero, x _i = 0). On the contrary, if the movement presence / absence discriminant variable y _i with respect to the steel material group i is 0 (zero, y _i = 1), one of the steel material group i and the steel material group _i above it in the initial mountain Sk. Only the non-moving uppermost steel material discriminant variable x _i for one steel material group i becomes 1 (x _i = 1). Therefore, for the steel material group i ∈ S _k , the set of the steel material group i and the steel material group i above it in the initial mountain Sk is _defined as Sk ^↑ (i) ₍ (14) below). (Refer to the equation), the following equation (13) holds.

In the equation (13), for any steel group _i of the initial mountain Sk, if the steel group i is a moving steel group, there is no non-moving steel group above it, and the steel group i is a moving steel group. If not, the steel group i or one of the steel groups above the steel group i becomes the non-moving steel group located at the top of the non-moving steel groups (that is, x _i = 1). There is only one steel group).

(E) Restrictions on transshipment For any payout order (steel material group) i, the non-moving uppermost steel material discriminant variable x _j is 1 (x _j =) in the steel material group j (≦ i) which is the payout order before i. If there is a steel material group j (non-moving steel material group) that becomes 1), in order to achieve the minimum total number z of the final peaks, (h-b _j ) x _j sheets are placed on the steel material group j. It is necessary to load steel materials. That is, in the initial mountain Sk, the total number of steel materials to be filled in the empty space to be filled by the moving steel material on the non-moving steel material _i at the uppermost stage among the non-moving steel materials is Σ _{j: i} ≧ _j (hb). _j ) ・ x _j There will be. The steel material that can be loaded in this empty space must be a mobile steel material whose payout order is q (≦ i). The total number of moving steel materials is Σ _{q: i} ≧ _q y _q · w _q . Therefore, this constraint can be described by the following equation (15).

The left side of Eq. (15) is in the non-moving steel material group when there is a non-moving steel material group in the initial mountain _{Sk (when the non-moving top-stage steel material discriminant variable x j is 1 (x j = 1} )). Indicates the empty space (number of steel materials) created above the non-moving steel material group j at the top. This empty space should be filled with mobile steel. The necessary condition for moving the moving steel material to this empty space is that the moving steel material group (y _q = 1) has a transport order q of i or less. Since the right-hand side of equation (15) represents the total number of mobile steel materials included in the mobile steel material group, the constraint of equation (15) is imposed.

Each equation with i fixed in equation (15) is a necessary condition, but by imposing the constraint of equation (15) on any payout order i (∈ N), it moves to the above-mentioned empty space. Sufficiency can be met to ensure the number of moving steels needed to make it. And since the right side (greater than) of the inequality sign in equation (15) is the amount to be minimized (the number of moving steel materials), it will not increase more than necessary. It can be seen as a constraint that matches the number. Further, in equation (15), the lower limit of the moving presence / absence discriminant variable y _q that reflects the number of moving steel materials to be minimized is expressed by the non-moving uppermost steel material discriminating variable x _j that reflects the number of non-moving steel materials to be maximized. On the other hand, the upper limit of the non-moving top-stage steel material discrimination variable x _j , which reflects the number of non-moving steel materials, is regulated by the moving presence / absence discrimination variable y _q , which reflects the number of moving steel materials to be minimized. Can be described. Therefore, Eq. (15) becomes a very strong constraint, and it can be expected that the optimum solution can be easily obtained.

However, if the formula (15) remains, the number of moving steel materials is requested too much. This is because there is no need for moving steel material for (z · hn). For example, if the total number z of the final ridges is 3, the upper limit h of the height of the final ridges is 10, and the number of steel materials is 28, then two (= 3 × 10-28) moving steel materials are used. , The total number of final mountains can be minimized (3 in this example) without moving to an empty space. Therefore, in order to correct this point, if nd = (z · h− _n ) (≧ 0), the following equation (15') may be used.

(F) Width / length constraint In this embodiment, when determining the moving steel group and the non-moving steel group, the mountain shape of the final mountain is not specified, so the stacking constraint (width constraint and length constraint) is completely satisfied. It is difficult to consider. However, stacking constraints (width constraints and length constraints) between the non-moving steel group and the moving steel group can be dealt with. Therefore, in the present embodiment, a stacking constraint (width constraint and length constraint) is imposed between the non-moving steel material group and the moving steel material group.

Specifically, in the initial mountain _Sk , the steel group that can be moved onto the non-moving steel group j (steel group j where x _j = 1) at the top of the non-moving steel groups is in the order of transportation. Is a steel material group of i (≦ j), and must satisfy the stacking constraint (width constraint and length constraint) with the steel material group j. Let I _j be a set of steel group i that satisfies this condition. Then, if the number of elements | I _j | of the set is less than the empty space (= h-b _j ), the steel material group j cannot be the uppermost non-moving steel material group among the non-moving steel material groups (. The non-moving uppermost steel material discriminant variable x _j with respect to the steel material group j can be regarded as 1 (x _j = 1)). This constraint can be described as the following equations (16) and (17).

It can be said that the constraint equation of the equation (16) is too strong in that the margin (= _nd ) considered in the equation (15') is not taken into consideration. On the other hand, for different steel material groups j, a set of steel material groups I whose transport order is i (≦ j) and which satisfies the stacking shape constraint (width constraint and length constraint) with the steel material group j. Since _j is considered to be duplicated, Eq. (16) is not a sufficient condition but a necessary condition. Further, in the equation (16), the stacking constraint (width constraint and length constraint) between the mobile steel material groups is not taken into consideration. However, this point will be taken into consideration in the post-processing described later.

The constraint expression / objective function setting unit 102 is, for example, S, _Sk , N, h, z, bi, _w with respect to the equations (7) to (13), (15'), and (16). By setting _i , _nd , and I _j , the constraint equations of equations (7) to (13), (15'), and (16) are set.

<< Objective function >>
Next, the objective function will be described.
As described above, in the present embodiment, since it is an object to minimize the total number of moving steel material groups or maximize the total number of non-moving steel material groups, the objective function shown in the following equation (18) or (19) is shown. Use J.

For example, when the constraint expression / objective function setting unit 102 uses the equation (18) as the objective function J, i is set for the equation (18), and the equation (19) is used as the objective function J. Sets the objective function of Eq. (18) or Eq. (19) by setting _i and bi for Eq. (19).

[Optimization calculation unit 103, optimization calculation step S204]
The optimization calculation unit 103 of the objective function J of the equation (18) or the equation (19) within the range satisfying the constraint equations of the equations (9) to (13), (15'), and (16). The non-moving uppermost steel material discriminating variable x _j and the moving presence / absence discriminating variable y _i when the values are minimized are calculated as the optimum solution. Further, the calculation of the optimum solution can be realized by using a known algorithm (including the use of a solver or the like) for solving the optimization problem by a mathematical programming method such as a mixed integer programming method.

[Post-processing unit 104, post-processing step S205]
When the optimum solution of the non-moving uppermost steel material discriminant variable x _j and the moving presence / absence discriminating variable y _i is derived as described above, whether or not to move each steel material group included in the set N of the steel material groups (that is,). , Whether it is a mobile steel group or a non-moving steel group) can be determined. Furthermore, for non-moving steel groups, it is assumed that only the moving steel group is moved (transported) without moving (transporting). The mountain shape of the mountain may be determined as post-processing. Hereinafter, the details of the processing when the post-processing unit 104 determines the transport order of each steel material group when transshipping the steel material group from the initial mountain to the final mountain and the mountain shape of the final mountain will be described. As described above, in the present embodiment, the method described in Patent Document 3 is used to determine the transport order of the steel material group when transshipping the steel material group from the initial mountain to the final mountain, and the mountain shape of the final mountain. Further, in the present embodiment, which steel group is determined to be temporarily placed when determining the transport order of the steel group when transshipping the steel group from the initial mountain to the final mountain and the mountain shape of the final mountain. It is also decided whether to pile up on such a temporary mountain. Such determination of the shape of the temporary mountain can also be realized by a known technique. In this embodiment, a case where the method described in Patent Document 4 is used will be described as an example.

First, the outline of the optimization calculation described in Patent Document 3 will be described. Since the details of the optimization calculation are described in Patent Document 3, the detailed description thereof will be omitted here.
As described above, in Patent Document 3, the mountain sorting / transporting order variable x [i] [m] [s], the temporary placement determination variable y [p] [s ₁ ] [s ₂ ], and the optimum mountain existence determination variable Let δ [m] be the determinant. As constraint equations, one steel material group i is not assigned to a plurality of transport orders and a plurality of final piles (unique constraint of a transport lot), and a plurality of steel material groups i in one transport order s. Alternatively, a constraint that the final mountain m is not assigned (unique constraint in the transport order) and a stacking constraint (length constraint, width constraint, height constraint) are used. As the objective function J', as shown in the following equation (20), a weighted linear sum of the objective function J ₁ for evaluating the total number of final peaks and the objective function J ₂ for evaluating the total number of transports is used. ..

In addition, in the equation (20), the weighting coefficients Weight1 and Weight2 are set in advance depending on how much each evaluation item is emphasized, and are between each evaluation item (the number of mountains of the final mountain, the total number of times of transportation). Represents the balance of evaluation. For example, when the number of final peaks is an important evaluation item rather than the total number of transports of the steel material group, the size of the weighting coefficient Weight1 is made larger than the size of the weighting coefficient Weight2.

In Patent Document 3, the determination variable (mountain sorting / transport order variable x [i] [m] [s], temporary placement determination variable y [, which minimizes the value of the objective function J'within the range satisfying the above-mentioned constraint equation. Find p] [s ₁ ] [s ₂ ] and the optimum mountain existence determination variable δ [m]). From these decision variables, the transport order of each steel material group i and the mountain shape of the final mountain can be obtained. Here, among the variables in which the optimum solution y _opt [p] [s ₁ ] [s ₂ ] of the temporary placement determination variable is 1, if there is a variable in which s ₁ > s ₂ , the pair p of the steel material group Of these, the steel group above is subject to temporary placement. In this way, the steel material group i to be temporarily placed can be obtained.

Patent Document 3 is premised on moving all steel material groups. Therefore, when the method described in Patent Document 3 is applied assuming that the non-moving steel group is not moved (transported) but is moved (transported) only for the moving steel group as in the present embodiment, it is as follows. There is a need to.
First, the mountain sorting / transport order variable x [i] [m] [s] for the final mountain m of the steel material group i, which cannot be the same final mountain as the non-moving steel material group, is fixed to 0 (zero). As described above, the mountain sorting / transport order variable x [i] [m] [s] is 1 when the steel group i is transported to the final pile m in the transport order s, and 0 (zero) otherwise. It is a 0-1 variable.

For example, assuming that the initial mountain including the two steel groups i ₁ and i ₂ as the non-moving steel group is allocated to the final mountain m ₁ , the mountain shape constraint for the final mountain m ₁ is as follows (21). You need to add a constraint. Note that F (i ₁ ) represents a set of steel material groups that cannot be the same final pile as the steel material group i ₁ .

Further, the mountain height constraint of (Equation 4-1) and (Equation 4-2) of Patent Document 3 is rewritten as the following equations (22) and (23) in consideration of the non-moving steel material group.

Here, H _f is the sum of the thicknesses of the steel materials belonging to all the non-moving steel material groups. P _f is the total number of steel materials belonging to all non-moving steel material groups. H and P represent the upper limit of the height of the final mountain described by the thickness and the number of sheets, respectively. The thickness [i] is the sum of the thicknesses of the steel materials belonging to the steel material group i.

Then, by applying the method described in Patent Document 4 to the steel material groups determined to be temporarily placed as described above, it is possible to determine what kind of temporary pile the steel material groups should be combined into.
Here, the outline of the optimization calculation described in Patent Document 4 will be described. Since the details of the optimization calculation are described in Patent Document 4, the detailed description thereof will be omitted here.

In Patent Document 4, for each steel material group to be divided into piles, a set of steel material groups satisfying the pile-up constraint when stacking on the same pile as the steel material group is extracted, and the steel material satisfying the pile-up constraint is obtained by the branching method. Extract the feasible mountains that are a set of groups. As the constraint formula, a constraint formula is used indicating that no steel group must be used in duplicate in a plurality of feasible ridges and must be used in any one feasible ridge. Further, as the evaluation function, each feasible is the product of the decision variable, which is a 0-1 variable indicating whether or not the feasible mountain is adopted as the optimum solution, and the evaluation value when the feasible mountain is selected. Use the sum for the mountains. Find the decision variable (set of feasible mountains) that minimizes the value of the objective function within the range that satisfies the constraint expression.

Patent Document 4 shows a method for dividing undelivered materials into piles. Therefore, in order to apply the method described in Patent Document 4 to the steel material group determined to be temporarily placed, the undelivered material in Patent Document 4 is determined to be temporarily placed by the method described in Patent Document 3 described above. If the order of arrival at the yard in Patent Document 4 is regarded as the order of transportation to the temporary storage place of the steel material group determined to be temporary storage obtained by the method described in Patent Document 3 described above. good.

As described above, the post-processing unit 104 derives the transport order of the mobile steel material group, the mountain shape of the final mountain, and the mountain shape of the temporary mountain.

[Output unit 105, output step S206]
The output unit 105 outputs information derived from the post-processing unit 104, indicating the transport order from the initial pile to the final pile of each steel material group included in the steel material assembly N. The form of the output includes at least one of display on a computer display, storage in an internal or external storage medium of the yard management device 100, and transmission to an external device. Examples of the external device include a crane or a control device for controlling the operation of the crane.

(summary)
As described above, in the present embodiment, when the yard management device 100 constitutes the minimum number of final ridges determined by the upper limit of the height of the final ridges, the yard management device 100 is stacked on the non-moving steel material at the uppermost stage. It is determined that the number of moving _steel materials that can be made and the number of moving steel materials that need to be _stacked on the non-moving steel material match. Set the constraint expression to be expressed using. Then, in the yard management device 100, the value of the objective function J for the purpose of maximizing the total number of non-moving steel material groups (or minimizing the total number of moving steel material groups) so as to satisfy the set constraint equation is set. The non-moving top-stage steel material discriminating variable x _i and the moving presence / absence discriminating variable y _i at the maximum (or minimum) are derived, and the non-moving steel material group and the moving steel material group are determined. Therefore, when creating a steel transport plan for transshipping steel from the initial crest to the final crest, determine which steels need to be moved and which ones do not need to be moved so that the total number of final crests is minimized. Can be done.

<Calculation example>
Next, a calculation example will be described. In this calculation example, the non-moving steel material and the moving steel material are determined by the method of the present embodiment so as to maximize the total number of non-moving steel materials (or minimize the total number of moving steel materials), and the non-moving steel materials are not moved. On the premise that the moving steel material is moved to, the post-treatment based on Patent Documents 3 and 4 described in the present embodiment is performed to determine the transport order of each steel material and the shape of the final mountain. In this calculation example, the steel materials are not grouped into the steel material group, but the steel materials are transported one by one.

(Method of verification)
In this calculation example, assuming that the non-moving steel material determined by the method described in the present embodiment is correct, the post-treatment based on Patent Document 3 described in the present embodiment is executed, and the number of final peaks and the transport order of the steel material are executed. And ask. Originally, in the algorithm described in Patent Document 3, appropriate weight coefficients Weight1 and Weight2 are set for the total number of mountains and the total number of times of transportation of the final mountain, and the sum of the weights multiplied by them is minimized. However, in order to verify the algorithm for minimizing the total number of moving steel materials (maximizing the total number of non-moving steel materials) described in the present embodiment (referred to as "this algorithm" in the following description), the total number of final peaks is z. Is less than or equal to the number specified by Eq. (1). That is, according to the premise of this algorithm, if the transshipment of steel materials is performed based on the non-moving steel materials determined by this algorithm, the total number of final peaks should be the minimum number (= z) determined by the peak height limit. .. Therefore, in order to verify this point, this restriction (restriction that the total number of final peaks is z or less) is imposed on the post-processing based on Patent Document 3 described in the present embodiment. Then, the treatment based on Patent Document 4 described in the present embodiment is executed on the steel material determined to be temporarily placed by such a method, and the mountain shape of the temporary mountain is obtained.

Since this algorithm maximizes the total number of non-moving steel materials (minimizes the total number of moving steel materials) on the premise that the total number of final peaks is the minimum, the following verification is performed.
If the non-moving steel material obtained by this algorithm matches the partial peak max (S _k ), it can be regarded as the optimum solution. The partial peak max (S _k ) is described in the section of "(a) Restrictions on moving steel materials" (in the following explanation, this partial peak max (S _k ) is maximized as necessary. Partial peak max (S _k )).

On the other hand, if the non-moving steel material obtained by this algorithm does not match the maximum partial peak max (S _k ), the non-moving steel material (moving steel material) determined by this algorithm and the maximum partial peak max (S _k ) are used. ), And one of the steel materials determined to be a moving steel material while being included in the maximum partial peak max (S _k ) is changed to a non-moving steel material (the total number of non-moving steel materials is calculated from the optimum solution by this algorithm. (Add one), perform post-processing based on Patent Documents 3 and 4 described in this embodiment, and obtain the total number of final mountains and the like.

As a result of this post-processing, it is confirmed whether or not the total number of final peaks increases from the number (= z) defined by Eq. (1). If this algorithm is correct, the total number of final peaks should be larger than the number (= z) defined by Eq. (1) when more non-moving steel materials are specified than the optimum solution by this algorithm.

(Calculation condition)
The initial mountain shape is given based on the operation data, and the non-moving steel material and the moving steel material are distinguished by this algorithm. Then, on the premise of this, the post-processing based on Patent Documents 3 and 4 described in the present embodiment is executed to obtain the total number of final mountains and the like. For the non-moving steel material obtained by this algorithm, the number of non-moving steel materials is increased by one, post-treatment based on Patent Documents 3 and 4 described in the present embodiment is executed, and the total number of final peaks is obtained. From the total number of final peaks obtained, it is investigated whether the number of non-moving steel materials obtained by this algorithm is really the maximum number (optimum value).

Here, the upper limit value h of the height of the final mountain is set to 10 steps (h = 10). Further, the weighting coefficients Weight1 and Weight2 in the equation (20) were set to 10 and 1 (Weight1 = 10, Weight2 = 1), respectively. However, when a constraint is applied to Patent Documents 3 and 4 described in the present embodiment that the total number of final peaks is not less than or equal to the number (= z) defined by Eq. (1), the weighting coefficient Weight 1 of Eq. (20) is set. It is set to 0 (zero, (Weight1 = 0)).

The calculation environment is as follows.
Processor: Intel (registered trademark) Xeon (registered trademark) CPU E5-2687W @ 3.1GHz (2 processors)
Mounted memory (RAM): 128GB
OS: Windows (registered trademark) 7 Professional 64-bit operating system Optimal calculation software: ILOG CPLEX (registered trademark) Cplex11.0 Concert25

FIG. 3 shows an example of a list of steel materials to be transshipped.
In FIG. 3, SL ID is an identification number of a steel material. The payout order is the order of transportation from the last pile to the next process. The width is the width of the steel material, and the length is the length of the steel material. The yard is the identification number of the yard of the initial mountain, and the stack is the number of stacks from the bottom of the initial mountain. For example, a steel material having an SL ID of 229 has a payout order of 120, a width of 1365 [mm], a length of 9700 [mm], and indicates that the steel material has an identification number of 1 at the bottom of the initial mountain. Further, in FIG. 3, the steel material shown in gray indicates that the steel material is contained in the maximum partial peak max ( _Sk ).

First, the result of executing the method described in this embodiment (this algorithm and post-processing based on Patent Documents 3 and 4) will be described. FIG. 4 shows an example of the result.
In FIG. 4, the final mountain ID is the identification number of the final mountain, and the stack (next to the final mountain ID) is the number of stacks from the bottom of the final mountain. SL ID is an identification number of a steel material. The payout order is the order of transportation from the last pile to the next process. The width is the width of the steel material, and the length is the length of the steel material. Temporary placement indicates the presence or absence of temporary placement, and 0 (zero) indicates that there is no temporary placement. The order of initial delivery is the order of transportation from the initial mountain. The final delivery order is the delivery order from the temporary mountain. The temporary mountain ID is an identification number of the temporary mountain. The stack (next to the temporary mountain ID) is the number of stacks from the bottom of the temporary mountain. The initial mountain ID is an identification number of the initial mountain. The stack (next to the initial mountain ID) is the number of stacks from the bottom of the initial mountain.

When transshipping the initial crests shown in FIG. 3 to the minimum number (= z) of the final crests, the total number of moving steel materials was minimized by this algorithm, and as a result, the SL ID was 221 (initial crest ID = 2), 222. Five steel materials (slabs) of (initial mountain ID = 2), 219 (initial mountain ID = 2), 236 (initial mountain ID = 4), and 228 (initial mountain ID = 5) can be fixed as non-moving steel materials. Other steel materials became mobile steel materials. As shown in FIG. 4, using this result, the post-processing based on Patent Documents 3 and 4 described in the present embodiment was executed, and the final mountain shape, the temporary mountain shape, and the transport order were obtained. The result.

In FIG. 4, the steel material shown in gray is determined to be a non-moving steel material by this algorithm. In FIG. 4, the initial peaks having initial peak IDs of 2, 4, and 5 are peaks having non-moving steel materials. In this example, there is no pile of only moving steel materials, and as a result, the total number of final piles is 3 (= ceil (29/10)), and the total number of final piles is the number (= z) determined by equation (1). Become. Further, in this example, all the moving steel materials can be directly transported from the initial pile to the final pile without one temporary placement (in FIG. 4, "/" in the columns of the final delivery order, the temporary pile ID, and the stacking stage. Indicates that there is no value (this is the same in other figures).

Next, as described above, the steel material (SL ID is 221 (initial mountain ID = 2), 222 (initial mountain ID = 2)), 219 (initial mountain ID = 2), which is a non-moving steel material by this algorithm. One more non-moving steel material than 236 (initial mountain ID = 4) and 228 (initial mountain ID = 5) five steel materials), and for post-treatment based on Patent Documents 3 and 4 described in this embodiment. On the other hand, by imposing a constraint that the total number of the final mountains is z (= 3) or less, the mountain shape of the final mountain, the mountain shape of the temporary mountain, and the order of transportation were obtained.

First, as described above, the five steel materials designated as non-moving steel materials by this algorithm are replaced with six steel materials (SL ID is 221 (initial mountain ID = 2), 222 (initial mountain ID = 2)), 219 ( A case of changing to 6 steel materials of initial mountain ID = 2), 223 (initial mountain ID = 3), 224 (initial mountain ID = 3), and 228 (initial mountain ID = 5) will be described. That is, a case where the steel material having SL ID of 236 (initial mountain ID = 4) is replaced with the steel material having SL ID of 223 (initial mountain ID = 3) and 224 (initial mountain ID = 3) will be described.

In this case, the algorithm described in Patent Document 3 cannot be solved. Therefore, the upper limit of the total number of final mountains was changed from 3 to 4. As a result, the result shown in FIG. 5 was obtained. Thus, if the total number of non-moving steel materials was increased from the result of the solution by this algorithm, it was not possible to realize the minimum total number of final peaks.

Next, as described above, the five steel materials designated as non-moving steel materials by this algorithm are different from the above-mentioned six steel materials (SL ID is 221 (initial mountain ID = 2)) and 222 (initial mountain ID). = 2), 219 (initial mountain ID = 2), 225 (initial mountain ID = 8), 215 (initial mountain ID = 8), 236 (initial mountain ID = 4), 6 steel materials) explain. That is, a case where the steel material having the SL ID of 228 (initial mountain ID = 5) is changed to the steel material having the SL ID of 225 (initial mountain ID = 8) and 215 (initial mountain ID = 8) will be described.
In the previous example, the non-moving steel material with the initial pile ID of 4 was used as the moving steel material, and the moving steel material with the initial pile ID of 3 was used as the non-moving steel material. A non-moving steel material having an initial pile ID of 8 is used as a steel material, and a non-moving steel material having an initial pile ID of 8 is used as a moving steel material.

In this case as well, the algorithm described in Patent Document 3 cannot be solved. Therefore, the upper limit of the total number of final mountains was changed from 3 to 4. As a result, the result shown in FIG. 6 was obtained. In this example as well, it was not possible to minimize the total number of final peaks by increasing the total number of non-moving steel materials above the result of the solution by this algorithm. From the results shown in FIGS. 4, 5 and 6, the maximum value of the total number of non-moving steel materials for minimizing the total number of final peaks is the total number of non-moving steel materials obtained by this algorithm. Is inferred.

Next, steel material information based on the state of the initial mountain in actual operation is given to this algorithm, mobile steel material and non-moving steel material are determined by this algorithm, and on the premise of the determination, Patent Document 3 described in the present embodiment. The post-treatment based on 4 was carried out, and the mountain shape of the final mountain, the order of transportation, and the mountain shape of the temporary mountain were obtained. It was confirmed whether the total number of final peaks obtained from the result was the number z (the number determined by Eq. (1)) assumed by this algorithm. The results are shown in FIG.

In FIG. 7, the input data shows the data given to this algorithm. The minimization of the number of movements shows the result by this algorithm. The mountain transshipment problem shows the result of post-processing based on Patent Documents 3 and 4 described in the present embodiment.
Data is an identification number of input data. The number of SLs is the total number of steel materials (slabs) that make up the initial mountain. The initial number of mountains is the total number of initial mountains. The final number of peaks is the minimum value z (the number determined by the equation (1)) of the total number of final peaks determined from the height limit. The number of movements is the total number of moving steel materials determined by this algorithm. The fixed number of ridges is the total number of initial ridges including steel materials determined to be non-moving steel materials by this algorithm. The time is the calculation time [s] of this algorithm. The final number of ridges is the total number of final ridges determined by the post-processing based on Patent Documents 3 and 4 described in the present embodiment. The temporary placement number is the total number of steel materials determined to be temporarily placed in the post-treatment based on Patent Documents 3 and 4 described in the present embodiment. The number of temporary mountains is the total number of temporary mountains determined by the post-processing based on Patent Documents 3 and 4 described in the present embodiment.

As shown in FIG. 7, it is determined by the minimum value of the total number of final peaks determined from the height limit (the value in the column of the final peaks of the input data) and the post-processing based on Patent Documents 3 and 4 described in the present embodiment. It can be seen that the total number of final mountains (value in the column of the final number of mountains in the mountain transshipment problem) matches. In addition, regardless of which input data the total number of steel materials is about 30 to 50 is given to this algorithm, moving steel materials (non-moving steel materials) can be processed at high speed (at about 0.1 [s]) within a practical time. I was able to decide. Further, an average of 21.5% (= (7.83 / 36.5) × 100) steel material could be fixed as a non-moving steel material.

When transshipping (replacement) the steel materials of the initial piles that are not in the order of payout from the top in the yard, the steel materials are moved for each pile and a new storage place. If there is a part in the bottom layer of the initial mountain where the payout order is in descending order from the bottom to the top, make the best use of it and replace only the upper part of the initial mountain. In some cases, the total number of transports may be reduced. In the present embodiment, for the latter case, a solution algorithm (this algorithm) for a problem of minimizing the total number of moving steel materials (maximizing the total number of non-moving steel materials) under the condition that the total number of final peaks is kept to the minimum number. Was built. Then, in this calculation example, a verification test based on actual data shows that if the total number of non-moving steel materials is increased more than the result of the solution by this algorithm, the total number of final peaks will increase, and the validity of this algorithm is verified. Indicated. Moreover, in this calculation example, it was shown that a high-speed solution can be obtained by this algorithm.
As described above, given the mountain shape of the initial mountain, when transshipping the steel materials of the initial mountain to the final mountain stacked in the order of payout, the total number of the final mountain is the minimum determined from the upper bound of the mountain height. It is possible to create a transshipment transport plan to maximize the total number of non-moving steel materials (minimize the total number of moving steel materials) on the premise of the number of steel materials.

(Modification example)
In this embodiment, when the objective function J of the equation (18) is used, it is a minimization problem, and when the objective function J of the equation (19) is used, it is a maximization problem. However, for example, by multiplying the right side of the equation (18) by (-1), it may be a maximization problem. Similarly, for example, by multiplying the right side of the equation (19) by (-1), it may be a minimization problem. Further, the problem of maximizing the objective function may be obtained by multiplying each term on the right side of the equation (20) by (-1).

Further, although the case where the technique described in Patent Document 3 is used in the post-treatment has been described as an example, if a method for determining the mountain shape of the final mountain and the transport order of steel materials is used, Patent Document 3 is not necessarily used. It is not necessary to use the technique described in. For example, the technique described in Patent Document 5 may be used. In addition, it is not always necessary to obtain the shape of the temporary mountain in the post-processing. Further, the method for obtaining the mountain shape of the temporary mountain is not limited to the technique described in Patent Document 4. For example, the feasible mountain may be extracted without using the branching method. As described above, the post-treatment can be realized by a known technique.

Further, as a storage space between processes, a storage space between two manufacturing processes may be targeted, a semi-finished product may be targeted as a metal material, and a storage space between manufacturing processes and a shipping process may be targeted as a storage space between processes. , As a metal material, the final product may be targeted. At this time, when a plurality of metal materials are housed in a container for transportation and arrangement, the container containing the metal materials may be treated as one metal material. Further, the storage space between processes is not limited to the storage space in the metal manufacturing process, and may be targeted for general distribution and transportation between processes. In the field of logistics, it can be applied not only to the contents but also to the transportation and arrangement of containers. Therefore, in the present invention, the metal material includes any one of a final product, a semi-finished product, and a container.

<Other variants>
The embodiment of the present invention described above can be realized by executing a program by a computer. Further, a computer-readable recording medium on which the program is recorded and a computer program product such as the program can also be applied as an embodiment 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, or the like can be used.
In addition, the embodiments of the present invention described above are merely examples of embodiment of the present invention, and the technical scope of the present invention should not be construed in a limited manner by these. It is a thing. That is, the present invention can be implemented in various forms without departing from the technical idea or its main features.

100: Yard management device, 101: Steel material information acquisition unit, 102: Constraint formula / objective function setting unit, 103: Optimization calculation unit, 104: Post-processing unit, 105: Output unit

Claims (11)

The metal material of the initial pile consisting of the metal material piled up in the yard, which is the storage place between processes, is transported by the transport equipment, and the metal material piled up in the stacking order according to the delivery order to the post-process of the yard. When creating the final mountain, the moving metal material, which is a metal material transported from the initial mountain to the final mountain in the storage place, and the initial mountain in order to create the final mountain in the same place as the initial mountain. It is a yard management device for determining the non-moving metal material to be fixed in the place of
The non-moving uppermost metal material discriminating variable indicating whether or not the metal material constituting the initial mountain is the metal material at the uppermost stage among the non-moving metal materials in the initial mountain, and the metal material. The determinant is a moving presence / absence discriminant variable that indicates whether or not is a moving metal material.
The minimum integer value equal to or greater than the value obtained by dividing the total number of the metal materials constituting the initial mountain by the height upper limit value which is the upper limit of the number of the metal materials constituting the final mountain is the final mountain. The total number
Metallic material information acquisition means for acquiring metal material information including the identification information of the initial mountain, the identification information of the metal material at each stacking position of the initial mountain, and the payout order of the metal material.
When all the payout orders are set, the number of the moving metal materials whose payout order is before the payout order arbitrarily set is the payout order whose payout order is before the voluntarily set payout order. Transshipment, which is a constraint equation using the coefficient of determination, indicates that the number of non-moving metal materials required is greater than the number of moving metal materials that can be stacked on the non-moving metal material at the top. A constraint expression setting means for setting a constraint expression including a constraint expression based on the metal material information, and a constraint expression setting means.
The purpose of setting the objective function for the purpose of minimizing the total number of the moving metal materials or the objective function for the purpose of maximizing the total number of the non-moving metal materials based on the metal material information. Function setting means and
Optimization executed by performing optimization calculation by a mathematical programming method to derive the value of the decision variable when the value of the objective function becomes the minimum or the maximum within the range satisfying the constraint equation as the optimum solution. Calculation means and
A yard management device characterized by having. The non-moving metal material does not move from the initial mountain, but moves the moving metal material to perform transshipment from the initial mountain to the final mountain, and the respective transport order of the metal material. The yard management device according to claim 1, further comprising a post-treatment means for determining the metal material arranged in each stage of the final mountain. The total number of metal materials that need to be stacked on the non-moving metal material at the top of the non-moving metal material is the bottom of the non-moving metal material at the top of the non-moving metal material. It is a value obtained by subtracting the surplus from the sum of the values obtained by subtracting the product stage counted from the upper limit of the height.
According to claim 1 or 2, the surplus is a value obtained by subtracting the total number of the metal materials constituting the initial mountain from the value obtained by multiplying the total number of the final mountains and the upper limit of the height. The described yard management device. In the transshipment constraint formula, when all the payout orders are set, the payout order is the sum of the number of the moving metal materials and the surplus, which is the payout order before the payout order arbitrarily set. It is necessary for the number of moving metal materials that can be stacked on the non-moving metal material at the top of the non-moving metal materials that are in the payout order before the arbitrarily determined payout order. The yard management device according to claim 3, wherein the yard management device is a constraint expression indicating. The constraint formula uses the determination variable to indicate that the sum of the total number of the moving metal materials and the total number of the non-moving metal materials is equal to the total number of the metal materials constituting the initial mountain. The yard management device according to any one of claims 1 to 4, further comprising a first variable-related regulation constraint equation. In the constraint equation, when the metal material is the moving metal material, the metal material above the metal material in the initial mountain does not become the non-moving metal material, and the metal material is the non-moving metal material. In the case of a metal material, only one of the metal material or the metal material above the metal material in the initial mountain becomes the metal material at the uppermost stage among the non-moving metal materials. The yard management device according to any one of claims 1 to 5, further comprising a second variable-related regulation constraint expression represented by using the determination variable. In the constraint formula, the moving metal material that is moved above the non-moving metal material at the top of the non-moving metal material has a payout order that is higher than the payout order of the non-moving metal material. It further includes a stacking constraint equation using the determinants to indicate that the constraints determined by the width and length of the metal material must be satisfied before and with the non-moving metal material. The yard management device according to any one of claims 1 to 6, wherein the yard management device is characterized. The movement is performed in units of metal group,
The yard according to any one of claims 1 to 7, wherein the metal material group is composed of a plurality of the metal materials that are not divided when the metal material is transported by a transport device. Management device. The yard is a storage place between the steelmaking process and the rolling process in the steelmaking process.
The yard management device according to any one of claims 1 to 8, wherein the metal material is a steel material. The metal material of the initial pile consisting of the metal material piled up in the yard, which is the storage place between processes, is transported by the transport equipment, and the metal material piled up in the stacking order according to the delivery order to the post-process of the yard. When creating the final mountain, the moving metal material, which is a metal material transported from the initial mountain to the final mountain in the storage place, and the initial mountain in order to create the final mountain in the same place as the initial mountain. It is a yard management method for determining the non-moving metal material to be fixed in the place of
The non-moving uppermost metal material discriminating variable indicating whether or not the metal material constituting the initial mountain is the metal material at the uppermost stage among the non-moving metal materials in the initial mountain, and the metal material. The determinant is a moving presence / absence discriminant variable that indicates whether or not is a moving metal material.
The minimum integer value equal to or greater than the value obtained by dividing the total number of the metal materials constituting the initial mountain by the height upper limit value which is the upper limit of the number of the metal materials constituting the final mountain is the final mountain. The total number
A metal material information acquisition step for acquiring metal material information including the identification information of the initial mountain, the identification information of the metal material at each stacking position of the initial mountain, and the payout order of the metal material.
When all the payout orders are set, the number of the moving metal materials whose payout order is before the payout order arbitrarily set is the payout order whose payout order is before the voluntarily set payout order. Transshipment, which is a constraint equation using the coefficient of determination, indicates that the number of non-moving metal materials required is greater than the number of moving metal materials that can be stacked on the non-moving metal material at the top. A constraint expression setting step for setting a constraint expression including a constraint expression based on the metal material information, and
The purpose of setting the objective function for the purpose of minimizing the total number of the moving metal materials or the objective function for the purpose of maximizing the total number of the non-moving metal materials based on the metal material information. Function setting steps and
Optimization executed by performing optimization calculation by a mathematical programming method to derive the value of the decision variable when the value of the objective function becomes the minimum or the maximum within the range satisfying the constraint equation as the optimum solution. Calculation steps and
A yard management method characterized by having. A program characterized in that a computer functions as each means of the yard management device according to any one of claims 1 to 9.

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