A method for planning ship steel plate outbound operations in cutting operations

Abstract

The present invention provides a method for planning ship steel plate outbound operations for cutting operations, comprising: utilizing a cutting task plan and a yard management system to obtain cutting, yard, and driving operation parameters, and determine the number of blocking plates in a stacking position; employing a rule-based heuristic algorithm to generate an initial outbound sequence for the cut steel plates; employing a variable neighborhood search algorithm to update and search the outbound sequence for the cut steel plates; constructing a mixed integer programming model based on the given outbound sequence for the cut steel plates to determine a plate turnover plan and total operation time; determining whether a method stop condition has been met, and outputting the outbound operation plan for the steel plates determined by the method. The method of the present invention can plan outbound operation plans based on different cutting task requirements, providing the cutting line with cut steel plates in a timely and efficient manner, and reducing cutting waiting time.

Description

Technical Field

[0001] The present invention relates to the technical field of steel plate outbound delivery, and in particular to a method for planning outbound delivery operations of ship steel plates oriented to cutting operations. Background Art

[0002] Steel plates are the raw material used in the production of ship sections. Shipyards hold a large quantity of steel plates, making their extraction and transportation a significant constraint on shipbuilding capacity. Shipyards process large quantities of steel plates daily, making it difficult to predict when these plates will enter and exit the warehouse. Cutting is the first step in shipbuilding, and cutting efficiency directly impacts subsequent ship production and, in turn, the entire shipbuilding cycle. The steel plate removal process for cutting operations requires the yard to remove steel plates according to the cutting task requirements to feed multiple cutting lines.

[0003] In the early days of the shipbuilding industry, the loading and unloading process at the steel plate yard relied on manual labor and simple rules, without a systematic and rational plan. This led to insufficient loading time and waiting times for cutting machines. As competition intensified and shipyards demanded greater capacity and efficiency, the inefficiency of time wasted in the steel plate yard became a major factor hindering shipyard capacity expansion. Therefore, to overcome the high costs, low efficiency, and poor results of the existing manual steel plate yard system in shipyards, a new method for planning steel plate yard loading for cutting operations was needed. Summary of the Invention

[0004] In response to the defects in the existing technology, the purpose of the present invention is to provide a ship steel plate yard outbound operation planning method for cutting operations. The present invention can plan the outbound operation plan according to different cutting operation task requirements, provide cutting steel plates to the cutting line in a timely and efficient manner, and reduce the cutting waiting time.

[0005] In order to solve the above problems, the technical solution of the present invention is:

[0006] A method for planning ship steel plate outbound operations for cutting operations includes the following steps:

[0007] Using the cutting task plan and yard management system, obtain the cutting, yard and driving operation parameters and determine the number of baffles at the stacking location;

[0008] A rule-based heuristic algorithm is used to generate the initial order of cutting steel plates out of the warehouse;

[0009] The variable neighborhood search algorithm is used to update the outbound sequence of cut steel plates;

[0010] Based on the given cut steel plate outbound order, a mixed integer programming model is constructed to determine the plate turning plan and the total operation time;

[0011] Determine whether the method's stop condition has been reached, and output the yard steel plate outbound operation plan determined by the method.

[0012] Preferably, the step of utilizing the cutting task plan and the yard management system to obtain the operating parameters of cutting, yard and crane, and determining the number of baffles at the stacking position specifically includes: from the cutting task plan, it is necessary to determine the list of cutting steel plates, the cutting line where each steel plate is located, and the cutting hours for each steel plate; from the yard management system, it is necessary to determine the number of stacking positions, the capacity of each stacking position, and the position of the steel plate at the stacking position; the crane operating parameters need to clarify the time for the crane to grab and put down the steel plate, the time for the crane to move between different stacking positions, and the time for the steel plate to move from the yard to the cutting line; the number of baffles at the stacking position is defined as the number of non-cutting steel plates above the cutting steel plate.

[0013] Preferably, in the step of using the cutting task plan and yard management system to obtain the operating parameters of cutting, yard and driving, and determining the number of blocking plates in the stack, a breadth-first search algorithm is used to search each stack to determine the stack information and storage location of the steel plates required to be shipped out on the current date; and the breadth-first search algorithm is used to determine the moving time of the driving between different stacks.

[0014] Preferably, the step of using a rule-based heuristic algorithm to generate the initial outbound order of the cut steel plates specifically includes: first finding a stack with the least number of blocking plates, and adding the cut steel plates above it to the outbound sequence from top to bottom; then, determining the stack closest to the previous outbound stack, and adding all the outbound steel plates on it to the outbound sequence from top to bottom, and repeating this process until all the cut steel plates are added to the outbound sequence.

[0015] Preferably, in the step of using a rule-based heuristic algorithm to generate the initial order of outbound delivery of the cut steel plates, the stack position is used as the basic unit for determining the initial order of outbound delivery of the cut steel plates, and the steel plates in the same stack position are delivered from top to bottom in sequence; if in a certain selection, there are more than two stack positions with the same distance, the stack position with the least number of blocking plates is selected first.

[0016] Preferably, in the step of using a variable neighborhood search algorithm to update and search the outbound sequence of the cut steel plates, the method for updating the outbound sequence of the cut steel plates includes two updating methods. The first method for updating the outbound sequence of the cut steel plates is: removing the steel plates in a random part of the sequence, and inserting them back into the sequence in a random manner; the second method for updating the outbound sequence of the cut steel plates is: removing the steel plates in a certain segment of the sequence, and inserting them back into the original segment of the sequence in a random manner.

[0017] Preferably, in the step of constructing a mixed integer programming model based on the given cutting steel plate outbound sequence to determine the plate turning plan and the total operation time, if the expected operation time of the updated outbound sequence is better than the original outbound sequence, the original outbound sequence is discarded, the updated outbound sequence is retained, and the second method for updating the outbound sequence of the cutting steel plate is used to update the sequence; otherwise, the updated outbound sequence is discarded, the original outbound sequence is retained, and the first method for updating the outbound sequence of the cutting steel plate is used to update the sequence.

[0018] Preferably, in the step of determining whether the stopping condition of the method is reached and outputting the yard steel plate outbound operation plan determined by the method, the stopping condition is a fixed running time or the number of iterations.

[0019] Preferably, in the step of judging whether the stopping condition of the method is reached and outputting the yard steel plate outbound operation plan determined by the method, when the method reaches the stopping condition, the determined steel plate outbound sequence and barrier plate flipping sequence are expressed in a standardized semantic model as system output.

[0020] Compared to existing technologies, this invention addresses the time-consuming, labor-intensive, and ineffective manual process of shipyard steel plate destocking. It proposes a computer-based automated, intelligent analysis method and a corresponding management system that fully meets the practical needs of scheduling destocking operations for mixed, large-scale steel plate destocking. Regarding steel plate destocking operations, the method of this invention can plan destocking operations based on different cutting task requirements, providing the cutting line with cut steel plates in a timely and efficient manner, reducing waiting time for cutting. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Other features, objects and advantages of the present invention will become more apparent upon reading the detailed description of non-limiting embodiments with reference to the following drawings:

[0022] Figure 1 This is a flowchart of a method for planning ship steel plate delivery operations for cutting operations according to the present invention;

[0023] Figure 2 A flowchart of the rule-based method for generating the initial outbound order of cut steel plates;

[0024] Figure 3 This is a schematic diagram of the first method for updating the order of cutting steel plates out of the warehouse;

[0025] Figure 4 This is a schematic diagram of the second method for updating the order of cutting steel plates out of the warehouse. DETAILED DESCRIPTION

[0026] The present invention will be described in detail below with reference to specific embodiments. The following examples will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those skilled in the art, several changes and improvements can be made without departing from the scope of the present invention. These all fall within the scope of protection of the present invention.

[0027] Specifically, the present invention provides a method for planning ship steel plate outbound operations for cutting operations, such as Figure 1 As shown, the method includes the following steps:

[0028] S1: Using the cutting task plan and yard management system, obtain the cutting, yard and driving operation parameters and determine the number of baffles at the stacking location;

[0029] Specifically, the cutting task plan requires a list of plates to be cut, the cutting line for each plate, and the cutting time required for each plate. The yard management system requires the number of stacks, the capacity of each stack, and the location of the plates within each stack. The crane operating parameters must specify the time it takes to pick up and lower plates, the time it takes to move between stacks, and the time it takes to move plates from the stack to the cutting line. The number of blocking plates in a stack is defined as the number of non-cut plates above the cut plates.

[0030] Furthermore, in step S1, a breadth-first search algorithm is used to search each stack to determine the stack information and storage location of the steel plates required to be shipped out on the current date. The breadth-first search algorithm is also used to determine the travel time between different stacks.

[0031] S2: Generate the initial order of cutting steel plates out of the warehouse using a rule-based heuristic algorithm;

[0032] Specifically, if Figure 2 As shown, first find the stack with the least number of blocking plates and add the cut steel plates above it to the outbound queue from top to bottom. Then, find the stack closest to the previous outbound stack and add all the outbound steel plates above it to the outbound queue from top to bottom. Repeat this process until all cut steel plates are added to the outbound queue.

[0033] The stacking position is used as the basic unit to determine the order of the initial cut steel plates to be discharged. The steel plates in the same stacking position are discharged from the top to the bottom. Furthermore, if there are two or more stacking positions with the same distance in a certain selection, the stacking position with the least number of blocking plates will be selected first.

[0034] S3: Use variable neighborhood search algorithm to update the outbound sequence of cut steel plates;

[0035] Specifically, a variable neighborhood search algorithm is used to update the outbound sequence of cut steel plates. The outbound sequence of cut steel plates is updated according to the following rules:

[0036] Figure 3 This is the first method of updating the order of cutting steel plates out of the warehouse, such as Figure 3 As shown, a random portion of the steel plates in the sequence are removed and inserted back into the sequence in a random manner.

[0037] Figure 4 This is the second method for updating the order of cutting steel plates out of the warehouse, such as Figure 4 As shown, the steel plate of a certain segment in the sequence is removed and inserted back into the original segment of the sequence in a random manner.

[0038] S4: Based on the given cut steel plate outbound order, a mixed integer programming model is constructed to determine the plate turning plan and the total operation time;

[0039] Specifically, based on the given outbound sequence of cut steel plates, the stacking parameters related to the outbound sequence are determined, and the mixed integer programming model aims to minimize the total time of steel plate outbound and cutting operations.

[0040] After obtaining the steel plate delivery sequence and before constructing the mixed integer programming model, determine the intermediate parameters shown in Table 1 below:

[0041]

[0042]

[0043] Table 1 After this, the mixed integer programming model variables are determined as shown in Table 2 below:

[0044] variable type meaning <![CDATA[y sn ]]> Integer variables The number of blocks removed from location s at stage n <![CDATA[z sn ]]> Integer variables The number of blocks moved into position s at stage n <![CDATA[ot i ]]> Continuous variables Steel plate i's delivery time <![CDATA[ct i ]]> Continuous variables Cutting completion time of steel plate i <![CDATA[c max ]]> Continuous variables Makespan of the entire operation process

[0045] Table 2

[0046] Finally, a commercial or open source solver is used to solve the following mixed integer programming model:

[0047] min c max

[0048]

[0049] The result obtained in step S4 is the expected operation time under the outbound sequence. If the expected operation time of the outbound sequence updated in step S3 is better than the original outbound sequence, the original outbound sequence is discarded and the updated outbound sequence is retained. Otherwise, the updated outbound sequence is discarded and the original outbound sequence is retained.

[0050] Furthermore, if the original sequence is retained, step S3 will adopt Figure 3If the original sequence is discarded, the update method shown in step S3 will be used to update the sequence. Figure 4 The update method shown performs sequential updates.

[0051] S5: Determine whether the stop condition of the method is reached, and output the yard steel plate outbound operation plan determined by the method.

[0052] Specifically, the stopping condition may be a fixed running time or number of iterations. When the method reaches the stopping condition, the method outputs the yard steel plate outbound operation plan determined by the method according to specific rules; otherwise, the method returns to step S3.

[0053] The steel plate outbound operation plan determined by the specific rule output method is a system output that represents the determined steel plate outbound order and the blocking plate flipping order using a standardized semantic model. For example, a semantic model for the steel plate outbound operation plan is established using the steel plate number, stack location number, and steel plate movement method as basic semantic units. For example, the steel plate outbound statement = <steel plate number, steel plate stack location number, extract>, and the steel plate flipping statement = <steel plate number, steel plate stack location number, flip, flip plate landing number>. This constitutes a steel plate outbound operation plan that includes steel plate extraction and flipping operations.

[0054] The above describes specific embodiments of the present invention. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art may make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. The embodiments of this application and the features in the embodiments may be combined with each other in any manner unless there is a conflict.

Claims

1. A method for planning ship steel plate outbound operations for cutting operations, characterized in that: The method comprises the following steps: Utilize the cutting task plan and yard management system to obtain the operating parameters of cutting, yard and driving, and determine the number of blocking plates in the stacking position, including: from the cutting task plan, it is necessary to determine the list of cutting steel plates, the cutting line where each steel plate is located, and the cutting time of each steel plate; from the yard management system, it is necessary to determine the number of stacking positions, the capacity of each stacking position, and the position of the steel plate in the stacking position; the driving operation parameters need to clarify the time for the driving position to grab and put down the steel plate, the time for the driving position to move between different stacking positions, and the time for the steel plate to move from the yard to the cutting line; the number of blocking plates in the stacking position is defined as the number of non-cutting steel plates above the cutting steel plate; use the breadth-first search algorithm to search each stacking position to determine the stacking position information and storage location of the steel plates that need to be shipped out on the current date; use the breadth-first search algorithm to determine the moving time of the driving position between different stacking positions; A rule-based heuristic algorithm is used to generate the initial outbound order of cut steel plates. Specifically, the algorithm includes the following steps: first, find a stack with the least number of blocking plates, and add the cut steel plates above it to the outbound order from top to bottom; then, determine the stack closest to the previous outbound stack, and add all the outbound steel plates above it to the outbound order from top to bottom. This process is repeated until all cut steel plates are added to the outbound order; the stack is used as the basic unit for determining the initial outbound order of cut steel plates, and the steel plates in the same stack are outbound from top to bottom; if there are two or more stacks with the same distance in a certain selection, the stack with the least number of blocking plates is selected first. A variable neighborhood search algorithm is used to update and search the outbound sequence of cut steel plates. The method for updating the outbound sequence of cut steel plates includes two updating methods. The first updating method for the outbound sequence of cut steel plates is to remove steel plates from a random portion of the sequence and insert them back into the sequence in a random manner. The second updating method for the outbound sequence of cut steel plates is to remove steel plates from a certain segment of the sequence and insert them back into the original segment of the sequence in a random manner. Based on the given outbound order of cut steel plates, a mixed integer programming model is constructed to determine the plate turning plan and the total operation time. If the expected operation time of the updated outbound sequence is better than the original outbound sequence, the original outbound sequence is discarded, the updated outbound sequence is retained, and the second method for updating the outbound order of cut steel plates is used to update the sequence; otherwise, the updated outbound sequence is discarded, the original outbound sequence is retained, and the first method for updating the outbound order of cut steel plates is used to update the sequence; Determine whether the method's stop condition has been reached, and output the yard steel plate outbound operation plan determined by the method.

2. The method for planning ship steel plate outbound operations for cutting operations according to claim 1, characterized in that: In the step of determining whether the stopping condition of the method is reached and outputting the yard steel plate outbound operation plan determined by the method, the stopping condition is a fixed running time or the number of iterations.

3. The method for planning ship steel plate outbound operations for cutting operations according to claim 1, characterized in that: In the step of judging whether the stopping condition of the method is reached and outputting the yard steel plate outbound operation plan determined by the method, when the method reaches the stopping condition, the determined steel plate outbound sequence and blocking plate flipping sequence are expressed in a standardized semantic model as system output.

Images