A control method and system for achieving optimal slitting of a steel coil

Abstract

The application discloses a control method and system for realizing optimal slitting of a steel coil, the method is only for a production line with slitting capability, and the method comprises the following steps: determining an actual weight of raw material used for manufacturing a large coil; configuring a standard material yield according to historical data; calculating a single-coil weight range of small coils at an outlet of the production line based on unit capacity of different types of production lines; calculating an optimal slitting number range F according to a formula; wherein, roundup() is a rounding-up function, A is the actual weight of the raw material, C is the standard material yield, [G min , G max ] is the single-coil weight range, G min is a minimum value of the single-coil weight at the outlet of the production line, G max is a maximum value of the single-coil weight at the outlet of the production line, and 0 represents no decimal point; and the large coil is controlled to be divided into a plurality of small coils based on the optimal slitting number range in the production line with the slitting capability.

Description

Technical Field

[0001] This application relates to steel coil cutting, and more particularly to a control method and system for achieving optimal steel coil cutting. Background Technology

[0002] In the steel industry, a production model of organizing production in large coils and delivering in small coils is generally adopted.

[0003] Due to constraints imposed by transportation conditions and customer restrictions on further processing, orders for some steel products, especially cold-rolled products, generally require delivery in smaller coils. For example, a large domestic steel mill delivers its cold-rolled galvanized products in coil form, with a unit weight requirement of 5-8 tons. Statistics show that the proportion of small-coil deliveries can reach as high as 80%. Furthermore, due to limitations in the casting cycles and production capacity of steel mill furnaces, steel mills cannot produce small slabs, or producing small slabs would significantly impact production rhythm or yield, resulting in substantial cost losses for the steel mill. Therefore, currently, production is generally organized according to a model of producing large slabs and then cutting them into smaller coils in subsequent processes to meet both order weight requirements and steel mill cost control.

[0004] It is evident that, under the dual requirements of meeting customers' demands for small-coil heavy delivery and steel mills' own cost control, how to achieve optimal steel coil slitting has become an urgent problem to be solved.

[0005] Currently, most steel mills rely on manual estimation based on experience. Operators typically estimate the value of raw materials and order requirements using an enumeration method. This results in inaccurate estimations of the optimal slitting of steel coils, failing to meet both the customer's requirement for small, heavy coil delivery and the steel mill's own cost control requirements. Summary of the Invention

[0006] This invention provides a control method and system for achieving optimal steel coil slitting, in order to solve or partially solve the technical problem that existing technologies cannot meet both the customer's requirement for small coil weight delivery and the steel mill's own cost control requirements.

[0007] To address the aforementioned technical problems, a first aspect of the present invention discloses a control method for achieving optimal steel coil slitting, characterized in that the method is only applicable to production lines with slitting capabilities, and the method includes:

[0008] Determine the actual weight of the raw materials used to make the large roll;

[0009] Standard yield rate is configured based on historical data;

[0010] Based on the unit capacity of different types of production lines, calculate the range of single roll weights at the production line exit.

[0011] According to the formula Calculate the optimal range of cutting numbers F; where roundup() is the round-up function, A is the actual weight of the raw material, C is the standard yield, [G min G max [G] represents the weight range per roll. min G represents the minimum weight of a single roll exported from the production line. max This represents the maximum weight of a single roll exported from the production line; 0 indicates that no decimal places are retained.

[0012] Based on the optimal slitting range, the large roll is controlled to be slit into several smaller rolls on a production line with slitting capabilities.

[0013] Preferably, the calculation of the single-roll weight range of small rolls at the production line exit based on the unit capacity of different types of production lines specifically includes:

[0014] If the production line is a finished product production line, then use formula G. max =G 订单max G min =G 订单min The single-roll weight range G is calculated; where G 订单max G is the maximum value required for the order. 订单min This is the minimum value required for the order.

[0015] If the production line is not a finished product production line, then use formula G. max =G 订单max ×C' and G min =G 订单min The weight range G of a single roll is calculated by ×C'; where C' is the yield rate of each process downstream of the production line.

[0016] Preferably, the step of controlling the cutting of the large roll into several smaller rolls in a production line with cutting capabilities based on the optimal cutting number range specifically includes:

[0017] Determine the optimal segmentation number f from the range F of optimal segmentation numbers; where f ∈ F, F = [F min F max ], F min To minimize the optimal number of segments, F max The maximum value of the optimal number of segments;

[0018] Using formula Calculate the optimal weight G of a single roll of small rolls 最佳 ;

[0019] Based on the optimal weight of a single roll (G) 最佳 The control divides the large roll into several smaller rolls.

[0020] Preferably, determining the optimal segmentation number f from the optimal segmentation number range F specifically includes:

[0021] The minimum value within the range F of optimal slicing numbers is determined as the optimal slicing number f, where f = F. min .

[0022] A second aspect of the present invention discloses a control system for achieving optimal slitting of steel coils, the system being applicable only to production lines with slitting capabilities, the system comprising:

[0023] The first determining unit is used to determine the actual weight of the raw materials used to make the large roll;

[0024] Configuration unit, used to configure standard yield based on historical data;

[0025] The first calculation unit is used to calculate the range of single roll weights at the production line exit based on the unit capacity of different types of production lines.

[0026] The second calculation unit is used to calculate according to the formula. Calculate the optimal range of cutting numbers F; where roundup() is the round-up function, A is the actual weight of the raw material, C is the standard yield, [G min G max [G] represents the weight range per roll. min G represents the minimum weight of a single roll exported from the production line. max This represents the maximum weight of a single roll exported from the production line; 0 indicates that no decimal places are retained.

[0027] A control unit is used to control the cutting of the large roll into several smaller rolls in a production line with cutting capabilities based on the optimal cutting number range.

[0028] Preferably, the first computing unit is specifically used for:

[0029] If the production line is a finished product production line, then according to formula G max =G 订单max G min =G 订单min The single-roll weight range G is calculated; where G 订单max G is the maximum value required for the order. 订单min This is the minimum value required for the order.

[0030] If the production line is not a finished product production line, then use formula G. max =G 订单max ×C' and G min =G 订单min The weight range G of a single roll is calculated by ×C'; where C' is the yield rate of each process downstream of the production line.

[0031] Preferably, the control unit specifically includes:

[0032] The second determining unit is used to determine the optimal segmentation number f from the optimal segmentation number range F; where f ∈ F, F = [F min F max ], F min To minimize the optimal number of segments, F max The maximum value of the optimal number of segments;

[0033] The third calculation unit is used to utilize formulas Calculate the optimal weight G of a single roll of small rolls 最佳 ;

[0034] The control subunit is used to determine the optimal weight G of a single roll. 最佳 The control divides the large roll into several smaller rolls.

[0035] Preferably, the determining unit is specifically used to determine the minimum value in the optimal segmentation number range F as the optimal segmentation number f, where f = F. min .

[0036] A third aspect of the present invention discloses a computer-readable storage medium having a computer program stored thereon that, when executed by a processor, implements the steps of the above-described method.

[0037] A fourth aspect of the present invention discloses a computer device including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the steps of the above-described method.

[0038] Through one or more technical solutions of the present invention, the present invention has the following beneficial effects or advantages:

[0039] This invention discloses a control method and system for achieving optimal steel coil slitting. Based on the unit's capacity and the production line's exit weight requirements, and using objective data such as the actual weight of raw materials, standard yield, and the single coil weight range at the production line exit, the optimal slitting number range is calculated to control the coil slitting. This avoids losses caused by manual enumeration estimation and ensures that cost and output indicators are controlled during the production process while meeting order requirements, achieving the goal of optimal slitting number and maximum efficiency.

[0040] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and in order to make the above and other objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described below. Attached Figure Description

[0041] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings.

[0042] In the attached diagram:

[0043] Figure 1 A flowchart illustrating a control method for achieving optimal steel coil slitting according to an embodiment of the present invention is shown;

[0044] Figure 2 A schematic diagram of a control system for achieving optimal slitting of steel coils according to an embodiment of the present invention is shown. Detailed Implementation

[0045] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this invention will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0046] To address or partially address the technical problem that existing technologies cannot meet both customers' requirements for small-coil delivery and steel mills' own cost control needs, this invention discloses a control method and system for achieving optimal steel coil slitting. Based on the unit's capacity and the production line's exit weight requirements, a self-developed formula uses objective data such as the actual weight of raw materials, standard yield rate, and the single-coil weight range at the production line exit to calculate the optimal slitting number range to control coil slitting. This avoids losses caused by manual enumeration estimation and ensures that, while meeting order requirements, cost and output indicators are controlled during the production process, achieving the goal of optimal slitting number and maximum efficiency.

[0047] For ease of explanation and interpretation of the present invention, please refer to the following embodiments. Figure 1 A flowchart of a control method for achieving optimal steel coil slitting is disclosed. It is worth noting that the method in this embodiment is only applicable to production lines with slitting capabilities, i.e., production lines equipped with flying shears. A flying shear, also known as a shearing machine that performs transverse shearing of rolled materials, is a processing device capable of quickly cutting iron plates, steel pipes, paper rolls, etc. The method in this embodiment is applied to a control system for achieving optimal steel coil slitting, and this control system is capable of automatic flying shear slitting. The method in this embodiment includes the following steps:

[0048] Step 101: Determine the actual weight of the raw materials used to make the large roll.

[0049] In this embodiment, raw materials are prepared before manufacturing the steel coil, so the actual weight of the raw materials can be calculated. The control system in this embodiment can obtain the actual weight of the raw materials based on manual input or by calling from other systems. In this embodiment, the large coil is the steel coil before it is slitting.

[0050] Step 102: Configure the standard yield rate based on historical data.

[0051] In this embodiment, the standard yield rate can be calculated by the control system or manually based on historical data such as production line, grade, and specification group.

[0052] Step 103: Based on the unit capacity of different types of production lines, calculate the single roll weight range of small rolls at the production line exit.

[0053] In this embodiment, the unit capabilities of different types of production lines vary, and the single-roll weight range of the small-roll production line output also differs. Specifically, if the production line is a finished product production line, the maximum output weight equals the maximum order requirement, and the minimum output weight equals the minimum order requirement. Therefore, using formula G... max =G 订单max G min =G 订单min The single-roll weight range G is calculated; where G 订单max G is the maximum value required for the order. 订单min This is the minimum value required for the order.

[0054] If the production line is not a finished product production line, then each downstream process also has a yield rate. Therefore, formula G is used. max =G 订单max ×C' and G min =G 订单min The weight range G of a single roll is calculated by ×C'; where C' is the yield rate of each process downstream of the production line.

[0055] Step 104: Calculate the optimal range of number of segments according to the formula.

[0056] The formula in this embodiment is: F represents the optimal range of cutting numbers, roundup() is the round-up function, A is the actual weight of the raw material, C is the standard yield, [G min G max [G] represents the weight range per roll. min G represents the minimum weight of a single roll exported from the production line. max This represents the maximum weight of a single roll exported from the production line; 0 indicates that no decimal places are retained.

[0057] Specifically, through A×C and G minThe maximum number of slices is calculated from the ratio; then, the maximum number of slices is rounded up to obtain the optimal maximum number of slices, F. max For example, when the maximum value of the slicing number is the decimal 3.4, the result is rounded up to 4. Similarly, using A×C and G... max The minimum number of cuts is calculated from the ratio; then, the minimum number of cuts is rounded up to obtain the optimal minimum number of cuts, F. min For example, when the minimum value of the segment is 0.5, the result is rounded up to 1. Using F... min and F max Construct the optimal range of the number of segments, F.

[0058] Step 105: Based on the optimal slitting range, control the cutting of the large roll into several smaller rolls in a production line with slitting capability.

[0059] In this embodiment, since the flying shear is controlled by the control system of this embodiment, in order to more accurately control the splitting and improve the rationality of the splitting, this embodiment determines the optimal splitting number f from the optimal splitting number range F; where f∈F, F=[F min F max Specifically, since a smaller number of cuts results in less impact on the production line, this embodiment determines the minimum value within the optimal cut number range F as the optimal cut number f, where f = F. min Furthermore, using the formula Calculate the optimal weight G of a single roll of small rolls 最佳 And according to the optimal weight G of a single roll of small rolls 最佳 The control divides the large roll into several smaller rolls.

[0060] By controlling the number of slits calculated using this solution, we can increase production, improve the yield rate, and reduce the occurrence of spot transactions, thereby meeting both the customer's requirement for small-coil heavy delivery and the steel mill's own cost control requirements.

[0061] To verify the rationality of this solution, the results after the solution was actually put into production line were compared one by one with the results of manually enumerating the number of segments.

[0062] In terms of social benefits, manual enumeration of order weights has a low hit rate and makes order fulfillment difficult. After some slabs are produced into steel coils, improper coiling results in some unfinished coils not meeting order requirements, necessitating rework and impacting order fulfillment. This solution, however, calculates the optimal slitting range based on objective data such as the actual weight of raw materials, standard yield, and the single-coil weight range at the production line exit. This controls coiling, ensuring that unfinished coils meet order requirements in the same way as other small coils, eliminating the need for rework and improving order fulfillment, thus increasing customer satisfaction.

[0063] In terms of output, manual enumeration significantly impacts the production rhythm of steel coils, leading to increased costs. Specifically, on production lines requiring offline or slow-speed coiling, manual enumeration results in unreasonable coil quantities, reducing production efficiency. Taking offline coiling at a domestic steel mill as an example, each additional coil takes approximately 8 minutes to separate, impacting output by about 15 tons based on timed production. However, by adopting this solution to control coiling, the stability of the production line is significantly improved, ultimately increasing the average speed of the production line by 3%, thus enhancing the efficiency of coiling output.

[0064] In terms of economic benefits, manual enumeration easily results in the separation of coils that do not meet the order weight requirements. These coils can only be downgraded or sold as spot goods, with prices approximately 100 yuan / ton lower than those for typical futures orders, thus reducing profits. However, by using this method to control coil separation, no coils that do not meet the requirements will be separated, saving 2-3 yuan / ton in costs. Based on an annual production of 10 million tons, this translates to an annual increase in profits of 20-30 million yuan.

[0065] Based on the same inventive concept, the following embodiments disclose a control system for achieving optimal slitting of steel coils. It is worth noting that the system in this embodiment is only for production lines with slitting capabilities. See [link / reference]. Figure 2 The system includes:

[0066] The first determining unit 201 is used to determine the actual weight of the raw materials used to make the large roll;

[0067] Configuration unit 202 is used to configure the standard yield rate based on historical data;

[0068] The first calculation unit 203 is used to calculate the single roll weight range of small rolls at the production line exit based on the unit capacity of different types of production lines.

[0069] The second calculation unit 204 is used to calculate according to the formula Calculate the optimal range of cutting numbers F; where roundup() is the round-up function, A is the actual weight of the raw material, C is the standard yield, [G min G max [G] represents the weight range per roll. min G represents the minimum weight of a single roll exported from the production line. max This represents the maximum weight of a single roll exported from the production line; 0 indicates that no decimal places are retained.

[0070] Control unit 205 is used to control the cutting of the large roll into several smaller rolls in a production line with cutting capability based on the optimal cutting number range.

[0071] In an optional embodiment, the first computing unit 203 is specifically used for:

[0072] If the production line is a finished product production line, then according to formula G max =G 订单max G min =G 订单min The single-roll weight range G is calculated; where G 订单max G is the maximum value required for the order. 订单min This is the minimum value required for the order.

[0073] If the production line is not a finished product production line, then use formula G. max =G 订单max ×C' and G min =G 订单min The weight range G of a single roll is calculated by ×C'; where C' is the yield rate of each process downstream of the production line.

[0074] In one optional embodiment, the control unit 205 specifically includes:

[0075] The second determining unit is used to determine the optimal segmentation number f from the optimal segmentation number range F; where f ∈ F, F = [F min F max ], F min To minimize the optimal number of segments, F max The maximum value of the optimal number of segments;

[0076] The third calculation unit is used to utilize formulas Calculate the optimal weight G of a single roll of small rolls 最佳 ;

[0077] The control subunit is used to determine the optimal weight G of a single roll. 最佳 The control divides the large roll into several smaller rolls.

[0078] In an optional embodiment, the determining unit is specifically used to determine the minimum value in the optimal segmentation range F as the optimal segmentation number f, where f = F. min .

[0079] In practical applications, the control system of this solution utilizes an information system to calculate and identify the required parameters. Based on the formulas in the technical solution, it performs calculations using relevant formulas programmed into the control system, and incorporates the calculation results into the system's automatic control for automatic cutting. Alternatively, the optimal range of cutting counts and the optimal weight of each roll can be calculated manually, and the results can be displayed on the on-site operation interface or work plan provided by the control system. Operators can then manually control the cutting process according to the calculated results.

[0080] Based on the same inventive concept as in the foregoing embodiments, this embodiment of the invention also discloses a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of any of the methods described above.

[0081] Based on the same inventive concept as in the foregoing embodiments, this embodiment of the invention also discloses a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the steps of any of the methods described above.

[0082] Through one or more embodiments of the present invention, the present invention has the following beneficial effects or advantages:

[0083] This invention discloses a control method and system for achieving optimal steel coil slitting. Based on the unit's capacity and the production line's exit weight requirements, and using objective data such as the actual weight of raw materials, standard yield, and the single coil weight range at the production line exit, the optimal slitting number range is calculated to control the coil slitting. This avoids losses caused by manual enumeration estimation and ensures that cost and output indicators are controlled during the production process while meeting order requirements, achieving the goal of optimal slitting number and maximum efficiency.

[0084] The algorithms and displays provided herein are not inherently related to any particular computer, virtual system, or other device. Various general-purpose systems can also be used in conjunction with the teachings herein. The required structure for constructing such systems is apparent from the above description. Furthermore, this invention is not directed to any particular programming language. It should be understood that the contents of the invention described herein can be implemented using various programming languages, and the above description of specific languages ​​is for the purpose of disclosing the best mode of implementation of the invention.

[0085] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of the invention may be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0086] Similarly, it should be understood that, in order to simplify the invention and aid in understanding one or more of the various inventive aspects, in the above description of exemplary embodiments of the invention, various features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof. However, this disclosure should not be construed as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as reflected in the following claims, inventive aspects lie in fewer than all features of a single foregoing disclosed embodiment. Therefore, the claims following the detailed description are hereby expressly incorporated into this detailed description, wherein each claim itself is a separate embodiment of the invention.

[0087] Those skilled in the art will understand that modules in the device of the embodiments can be adaptively changed and placed in one or more devices different from that embodiment. Modules, units, or components in the embodiments can be combined into a single module, unit, or component, and further, they can be divided into multiple sub-modules, sub-units, or sub-components. Except where at least some of such features and / or processes or units are mutually exclusive, any combination can be used to combine all features disclosed in this specification (including the accompanying claims, abstract, and drawings) and all processes or units of any method or device so disclosed. Unless expressly stated otherwise, each feature disclosed in this specification (including the accompanying claims, abstract, and drawings) may be replaced by an alternative feature serving the same, equivalent, or similar purpose.

[0088] Furthermore, those skilled in the art will understand that although some embodiments herein include certain features included in other embodiments but not others, combinations of features from different embodiments are intended to be within the scope of the invention and form different embodiments. For example, in the following claims, any of the claimed embodiments can be used in any combination.

[0089] The various component embodiments of the present invention can be implemented in hardware, or as software modules running on one or more processors, or a combination thereof. Those skilled in the art will understand that microprocessors or digital signal processors (DSPs) can be used in practice to implement some or all of the functions of some or all of the components of the gateway, proxy server, or system according to embodiments of the present invention. The present invention can also be implemented as a device or apparatus program (e.g., a computer program and computer program product) for performing some or all of the methods described herein. Such programs implementing the present invention can be stored on a computer-readable medium or can be in the form of one or more signals. Such signals can be downloaded from an Internet website, provided on a carrier signal, or provided in any other form.

[0090] It should be noted that the above embodiments are illustrative of the invention and not restrictive, and that those skilled in the art can devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses should not be construed as limiting the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The invention can be implemented by means of hardware comprising several different elements and by means of a suitably programmed computer. In the unit claims enumerating several means, several of these means may be embodied by the same item of hardware. The use of the words first, second, and third, etc., does not indicate any order. These words can be interpreted as names.

Claims

1. A control method for achieving optimum slitting of a steel coil, characterized by, The method is only for a production line with slitting capability, and the method comprises: determining actual weight of raw materials for manufacturing large rolls; configuring a standard yield rate according to historical data; Based on the unit capacity of different types of production lines, the single roll weight range at the production line exit is calculated, specifically including: if the production line is a finished product production line, then the formula is used. , The calculated weight range of a single roll ;in, The maximum value required for the order. This is the minimum value required for the order; if the production line is not a finished product production line, then the formula is used. as well as The calculated weight range of a single roll ;in, The yield rate of each process in the downstream of the production line; According to the formula Calculate the optimal slitting number range ; wherein, is the ceiling function is the actual weight of the raw material, is the standard lumber yield, is the single roll weight range, is the minimum single roll weight at the line exit, is the maximum single roll weight at the line exit, 0 indicates that the decimal place is not retained. Based on the optimal slitting number range, the large roll is controlled to be cut into a plurality of small rolls in a slitting line with slitting capability, specifically comprising: determining an optimal slitting number from the optimal slitting number range ; wherein, , , the optimal slitting number minimum value is the optimal slitting number maximum value; the optimal single-roll weight of the small roll is calculated by a formula ; and the large roll is controlled to be cut into a plurality of small rolls according to the optimal single-roll weight of the small roll . ​​ 2. The method of claim 1, wherein, determining the optimal slitting number from the optimal slitting number range , and specifically comprises:​ determining the minimum value in the range of optimal slitting numbers as the optimal slitting number , .

3. A control system for achieving optimal slitting of a steel coil, characterized by, The system is only for a production line with slitting capability, and the system comprises: a first determining unit configured to determine actual weight of raw materials for manufacturing large rolls; a configuring unit configured to configure a standard yield rate according to historical data; The first calculation unit is configured to calculate a single roll weight range of the small roll at an outlet of a production line based on a unit capacity of the production line, in particular, if the production line is a finished product production line, the single roll weight range is calculated according to a formula , , ; wherein, is a maximum value of an order requirement, is a minimum value of the order requirement; if the production line is not a finished product production line, the single roll weight range is calculated according to a formula , , ; wherein, is a material yield of each process downstream of the production line. a second calculation unit configured to calculate the optimal slitting number range according to the formula ; wherein, is a ceiling function is the actual weight of the raw material, is the standard lumber yield, is the single roll weight range, is the minimum single roll weight at the line outlet, is the maximum single roll weight at the line outlet, and 0 indicates that no decimal places are retained.​ A control unit is configured to control cutting of the large roll into a plurality of small rolls based on the optimal cutting number range in a production line with cutting capability. The control unit specifically includes a second determination unit configured to determine an optimal cutting number from the optimal cutting number range ; wherein , , the optimal cutting number minimum value is the optimal cutting number maximum value; a third calculation unit configured to calculate a single-roll optimal weight of the small roll by using a formula ; and a control sub-unit configured to control cutting of the large roll into a plurality of small rolls according to the single-roll optimal weight of the small roll .​​ 4. The system of claim 3, wherein, The determining unit is specifically configured to determine the minimum value in the optimal slitting number range as the optimal slitting number , .​ 5. A computer-readable storage medium having stored thereon a computer program, characterized in that, The program, when executed by a processor, implements the steps of the method of any one of claims 1-2.

6. A computer device comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, The processor, when executing the program, implements the steps of the method of any one of claims 1-2.

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