Industrial internet data integration processing method and system

Abstract

The application relates to the technical field of data transmission, in particular to an industrial internet data integration processing method and system, which comprises the following steps: acquiring data required to be transmitted by each link node of the industrial internet in real time; presetting a time window, combining transmission conditions in the link, calculating a comprehensive influence index and a joint priority index of the bandwidth of each link node through a delay effect possibly caused by congestion, and using a resource allocation algorithm to allocate bandwidth according to the joint priority indexes of all the link nodes, and allocating bandwidth to each kind of data flow in the link node, and performing integrated processing on the transmitted industrial internet data. The application aims to improve stability and real-time performance in the data transmission process, so as to ensure the reliability and accuracy of subsequent integration.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of data transmission, in particular to an industrial internet data integration processing method and system. BACKGROUND

[0002] Due to the demand for the accelerated evolution of global manufacturing industry towards intelligence and networking, traditional industrial systems cannot meet the requirements due to the problems of data island and protocol heterogeneity, and industrial internet data integration can further build a unified data resource pool by integrating multi-source heterogeneous data, which can realize the optimization and maintenance of the whole process, and is gradually becoming the core driving force of the current manufacturing digital transformation. In the operation of industrial internet data integration, there are many data with high real-time requirements, and it is extremely important to ensure the stability and real-time performance of data transmission. The data volume of different nodes in the industrial chain is usually fluctuant, such as the surge of order demand due to special circumstances during factory processing, the surge of supply chain monitoring data, and the relatively flat real-time supply chain data volume under normal order volume. Therefore, reasonable bandwidth allocation for different data nodes in industrial internet data transmission is a key prerequisite for subsequent data integration.

[0003] In the data transmission process of industrial internet data integration, when allocating bandwidth for different real-time data transmission nodes, when the data volume of a certain data transmission node increases dramatically due to special circumstances (such as when the order volume increases, the equipment runs faster to meet the surge demand, and the sensor data reporting frequency increases), it may cause congestion in the data transmission channel. Traditional dynamic bandwidth allocation algorithms (such as static polling or fixed allocation) are difficult to respond in time and allocate appropriate bandwidth when the real-time data volume changes, which may cause high-frequency transmission failure and retransmission during data transmission, resulting in transmission delay or loss of real-time data and affecting the subsequent integration accuracy. SUMMARY

[0004] In view of the above, it is necessary to provide an industrial internet data integration processing method and system to solve the above problems.

[0005] The first aspect of the present application provides an industrial internet data integration processing method, which comprises:

[0006] extracting various transmission data of each link node in the industrial internet;

[0007] a preset time window, analyze the degree of influence of the bandwidth of each time window before the target time window, determine the bandwidth influence probability weight of each time window before the target time window, analyze the abnormal phenomenon of data transmission of each link node in each time window before the target time window, and combine the number of data retransmission to determine the comprehensive influence index of each link node in each time window before the target time window;

[0008] analyze the transmission abnormality of each link node in each time window before the target time window, combine the comprehensive influence index and the bandwidth influence probability weight to determine the joint priority index of each link node in the target time window, and divide the bandwidth allocation proportion of the link node; obtain the joint priority index of each transmission data of each link node after division, and combine the priority marked by each transmission data to allocate bandwidth for each transmission data;

[0009] The integrated processing is performed on the industrial internet data after transmission.

[0010] The bandwidth influence probability weight of each time window before the target time window is determined, and the bandwidth influence probability weight of each time window before the target time window is determined.

[0011] The continuous preset number of time windows before the target time window are numbered;

[0012] The negative correlation mapping result of the ratio of the number of each time window before the target time window to the preset number is taken as the bandwidth influence probability weight of each time window before the target time window.

[0013] The comprehensive influence index of each link node in each time window before the target time window is determined, and the comprehensive influence index of each link node in each time window before the target time window is determined.

[0014] The transmission data is transmitted in the form of data packets; based on the number of data packets that fail to transmit after the first retransmission in each time window before the target time window of each link node, the single retry invalidity coefficient is determined.

[0015] The negative correlation mapping of the retransmission number of each transmission failure data packet is taken as the index of the single retry invalidity, and the cumulative sum of the normalized values of the index results of all transmission failure data packets is taken as the comprehensive influence index of each link node in each time window before the target time window.

[0016] The single retry invalidity coefficient is specifically: the number of data packets that fail to transmit after the first retransmission in each time window before the target time window of each link node accounts for the number of transmission failure data packets.

[0017] The joint priority index of each link node in the target time window is determined, and specifically is:

[0018] The number of data packets with abnormal transmission in each time window before the target time window is analyzed to determine a link congestion rate of each link node;

[0019] Based on the link congestion rate and the comprehensive influence index, a transmission influence index is determined.

[0020] The bandwidth influence probability weight value ratio of each time window before the target time window of each link node is calculated as a weight of the transmission influence index, and a communication demand index of each link node in the target time window is obtained by weighted summation.

[0021] The numerical ratio of the communication demand index of each link node in the target time window is taken as the joint priority index of each link node in the target time window.

[0022] The link congestion rate is specifically the ratio of the number of data packets with transmission failure or transmission timeout in all transmitted data packets in each time window before the target time window of each link node.

[0023] The transmission influence index is specifically the product of the link congestion rate and the comprehensive influence index.

[0024] The specific process of the bandwidth allocation ratio division of the link node is:

[0025] The joint priority index is taken as the weight of each link node, the total transmission bandwidth is combined, and a resource allocation algorithm is used for bandwidth allocation to obtain the allocated bandwidth of each link node.

[0026] The specific process of the bandwidth allocation of each type of transmission data is:

[0027] The joint demand index of each type of data is multiplied by the corresponding priority to obtain the weight of each type of transmission data, the allocated bandwidth of each link node is combined, and a resource allocation algorithm is used to obtain the allocated bandwidth of each type of transmission data in each link node.

[0028] In a second aspect, the embodiments of the present application also provide an industrial internet data integration processing system, which includes a memory, a processor, and a computer program stored in the memory and running on the processor, and the processor implements the steps of the method described in any one of the above aspects when executing the computer program.

[0029] The beneficial effects of the above scheme are: in the industrial internet data integration processing operation process, when the data is transmitted to the central data platform through each link node, the rationality of the bandwidth allocation has a greater influence on the timeliness and stability of the data transmission of each link node, and then affects the subsequent integration processing. Therefore, the rationality of the bandwidth allocation based on data transmission is analyzed. Since in special cases, the amount of data that each link node needs to transmit may increase dramatically, resulting in different bandwidth requirements for different link nodes at different times. Considering that data congestion may occur when the amount of data increases, resulting in link data transmission congestion and failed retransmission, the number of data transmission failures and the frequency of failed data retransmission in each link node at different times are obtained. The present application considers that frequent retransmission caused by data congestion will have a prolonged impact on time, and the previous time window is weighted. In combination with the data transmission proportion of each link node in each time window and the high-frequency retransmission situation, the joint demand index of different link nodes in the target time window is constructed and used as the weight of each link node. The weighted maximum minimum fairness algorithm is used for bandwidth allocation. The rational bandwidth allocation of the link node is performed in time when a special situation occurs, improving the stability and real-time performance of data transmission and further ensuring the stability and accuracy of subsequent integration. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 A step flowchart of an industrial internet data integration processing method provided by an embodiment of the present application is shown in the figure.

[0031] Figure 2 An acquisition schematic diagram of a joint priority index provided by an embodiment of the present application is shown in the figure. DETAILED DESCRIPTION

[0032] In the description of the embodiments of the present application, the words "exemplary", "or", "for example" are used to mean as an example, illustration, or description. Any embodiment or design scheme described as "exemplary" or "for example" in the embodiments of the present application should not be interpreted as more preferred or more advantageous than other embodiments or design schemes. Rather, the use of "exemplary", "or", "for example" is intended to present the relevant concept in a specific manner.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as understood by those skilled in the art to which the present application belongs. The terms used in the specification of the present application are only for the purpose of describing the specific embodiments and are not intended to limit the present application.

[0034] It should be noted that the terms "first", "second" in the present application and the drawings are used to distinguish similar objects, and are not used to describe a specific order or sequence. The method disclosed in the embodiments of the present application or the method shown in the flowchart includes one or more steps for implementing the method, and the execution order of the steps can be interchanged with each other without departing from the scope of the present application, and some steps can also be deleted.

[0035] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs.

[0036] The specific scheme of the industrial internet data integration processing method and system provided by the present application will be specifically described below in combination with the drawings.

[0037] Please refer to Figure 1 , which shows the step flowchart of an industrial internet data integration processing method provided by an embodiment of the present application, and the method includes the following steps:

[0038] The first step is to extract various transmission data of each link node in the industrial internet.

[0039] When the industrial internet data integration processing operation is performed, it is considered that the data sources of the industrial internet platform are extensive and diverse, covering multiple dimensions such as device layer, production layer, enterprise layer, supply chain layer and external ecology. Therefore, data needs to be acquired from different link nodes through Internet of Things, industrial protocol, API interface, log file and other means and transmitted to the central data platform. The data to be acquired includes but is not limited to: real-time sensor data of temperature, current and device status code of the device and production link node through the sensor; order data, production scheduling data and material demand data acquired by the order and plan layer link node in real time; inventory data and logistics data acquired by the supply chain and logistics link node in real time; quality inspection data acquired by the quality and inspection link node.

[0040] After obtaining the data of each link, the data of each link needs to be preprocessed by the edge device first. The obtained data is time calibrated using the Network Time Protocol (NTP) to avoid data mismatch in subsequent integrated processing. The data obtained by using the sensor is input into the Z-score standardization, and the abnormal values in the output data are detected. In other embodiments, the quartile range method or DBSCAN abnormal value detection method can also be used for abnormal value detection. The obtained abnormal values are deleted, and then the sensor data after abnormal value processing is input into the linear interpolation. The interpolation result of the deleted and missing data position is calculated to interpolate the missing values. In other embodiments, the filling method or time series interpolation can also be used for missing value interpolation processing. All data is standardized using the lightweight protocol MQTT, and the data to be transmitted is packaged into a data packet for transmission to reduce the transmission pressure.

[0041] The second step is to preset a time window, analyze the bandwidth influence degree of the target time window by the previous time window, determine the bandwidth influence probability weight of each time window before the target time window, analyze the abnormal phenomenon of data transmission of each link node in each time window before the target time window, and determine the comprehensive influence index of each link node in each time window before the target time window combined with the number of data retransmission.

[0042] In the industrial internet data integration operation, the required integrated data is mainly obtained from different link nodes. Data problems are prone to occur in the process of data collection, transmission and integration. In the case of data acquisition and transmission, the transmission of different link nodes is different, and some special situations may occur, which may cause the data amount obtained by some link nodes to fluctuate greatly. In the multi-link data transmission, the data of the corresponding link may fail to be obtained due to the data congestion of a certain link node, so it is necessary to update the bandwidth allocation of different link nodes in real time to avoid the data transmission failure caused by the insufficient bandwidth allocation of a single link.

[0043] In view of the fact that when data is obtained through a multi-link node and transmitted to a central data platform, the data obtained by the multi-link data source may be congested due to the lack of timely bandwidth allocation when the data volume increases due to external reasons, such as a surge in order volume during an activity time, which causes the data volume of the supply chain node to surge. Data congestion often leads to transmission failures and frequent retransmissions. According to the continuity of congestion, when congestion occurs at the current time and causes a large amount of data retransmission, even if bandwidth allocation is performed at the current time, data transmission will still be affected by the retransmission data, and part of the bandwidth will be occupied, thereby causing the congestion in the previous period to continue to the current time, affecting the transmission efficiency at the current time. Based on this, a time window is first set, starting from 0 o'clock each day, and every N minutes is set as a time window. The application does not make special restrictions on this. To avoid the impact of a long update interval on the congestion situation, the specific value is set according to the specific needs of the implementer. In this embodiment, the value of N is 6.

[0044] Based on this, when analyzing the influence of the previous time on the bandwidth allocation at the current time, a sliding region selection is performed on the obtained time window, and any time window is taken as a target time window. The application sets that a preset number of time windows before the target time window have an influence on the bandwidth allocation of the target time window. To ensure that time windows that are too far apart in the previous period do not affect the bandwidth allocation of the target time window, the specific value is set according to the specific needs of the implementer. In this embodiment, the value of the preset number is 5. An influence time window weight is constructed to represent the bandwidth influence probability weight of the time windows of the previous period with different time intervals on the target time window. First, the consecutive time windows before the target time window are numbered by taking an integer between 1 and 5 according to the time interval from the target time window to the farthest time window. When there are less than 5 time windows, the mean value is used to fill in the missing values.

[0045] The negative correlation mapping result of the ratio of the number of each time window before the target time window to the preset number is taken as the bandwidth influence probability weight of each time window before the target window. In this embodiment, the negative correlation mapping of the variable is obtained by taking the inverse of the variable as the exponent of the exponential function with the natural constant as the base, and taking the result of the exponential function as the negative correlation mapping result of the variable.

[0046] It should be understood that the influence degree of the bandwidth allocation of the adjacent time windows is weighted by the exponential function. The closer the previous time window is to the target time window, the greater the bandwidth influence probability weight, and the greater the influence of the time window on the bandwidth allocation of the target time window. Conversely, the farther the time window is from the target time window, the smaller the influence.

[0047] Further, each link node is analyzed, considering that when the link node is congested due to special circumstances, a part of the data will appear transmission failure and retransmission, and when these data are retransmitted, the bandwidth will be occupied again, and the more the number of failures (i.e. the more the number of attempts to retransmit), the greater the demand for bandwidth.

[0048] Based on this, taking each link node as an example, a comprehensive influence index is constructed to represent the influence of the data failure retransmission frequency of the corresponding link node on the bandwidth in the target time window: for each link node, the proportion of the number of data packets that fail for the first time after transmission failure in the number of transmission failure data packets in each time window before the target time window is obtained, to obtain the single retry invalidity coefficient of each link node in each time window before the target time window; the negative correlation mapping of the retransmission number of each transmission failure data packet is taken as the index of the single retry invalidity, and the cumulative sum of the normalized values of the index results obtained by all transmission failure data packets is taken as the comprehensive influence index of each link node in each time window before the target time window.

[0049] In this embodiment, the normalization method adopts sigmoid function for normalization, and the comprehensive influence index of the i-th link node in the k-th time window before the target time window is denoted as , and the formula form is: ; in the formula, , wherein W represents the total number of transmission failure data packets of the i-th link node in the k-th time window before the target time window; , wherein the normalization function is selected as Sigmoid function in this embodiment; is the single retry invalidity coefficient of the i-th link node in the k-th time window before the target time window; , wherein n represents the number of retransmission of each transmission failure data packet.

[0050] It should be understood that the more the number of retransmission of the failed transmission data packet, the greater the bandwidth burden caused, and the greater the value of obtained by calculation, and vice versa, the fewer the number of retransmission, the smaller the relative bandwidth burden caused, and the smaller the value of obtained by calculation.

[0051] The third step is to analyze the transmission anomalies of each link node in each time window before the target time window, and combine the comprehensive impact index and bandwidth impact probability weight to determine the joint priority index of each link node in the target time window, and divide the bandwidth allocation ratio of the link nodes; obtain the joint priority index of each type of transmission data on each link node after division, and combine the priority of each type of transmission data to allocate bandwidth for each type of transmission data.

[0052] Considering the high frequency of transmission channel congestion and transmission timeouts / failures caused by large data volumes during data transmission at link nodes, more bandwidth needs to be allocated. Therefore, taking the target time window of each link node as an example, a communication demand index is constructed to characterize the probability weight of the bandwidth demand for communication transmission of the corresponding link node within the target time window: The percentage of data packets experiencing transmission failures or timeouts in each time window before the target time window for each link node is obtained and recorded as the link congestion rate. The positive fusion result of the link congestion rate and the comprehensive impact index is used as the transmission impact index for each link node in each time window before the target time window. In this embodiment, the positive fusion of multiple variables is performed using a multiplication calculation method.

[0053] The bandwidth impact probability weight percentage of each link node in each time window before the target time window is calculated and used as the weight of the transmission impact index. The weighted sum is then used to obtain the communication demand index of each link node in the target time window.

[0054] It should be understood that by weighting the communication demand index of each link node within the target time window, the more data that fails to transmit within the time window and fails again after one retransmission, the greater the demand for subsequent bandwidth due to congestion in the link. Simultaneously, the higher the link transmission congestion rate in the preceding time window, the higher the proportion of data experiencing transmission failures, resulting in a larger overall communication demand index value and requiring more bandwidth allocation. Conversely, when the number of data that fails to transmit within the time window and fails again after one retransmission approaches zero, and the link transmission congestion rate in the preceding time window is also low, it indicates that the data transmission channel is relatively stable within the weighted time window, resulting in a smaller overall communication demand index value and requiring less bandwidth allocation. Therefore, channels with high bandwidth demands are given higher weights.

[0055] After calculating the communication demand index of each link node, the bandwidth allocation priority of each link node is calculated, and the joint demand index is constructed to predict the proportion of the bandwidth allocation demand of each link node in all link nodes in the target time window: the numerical value of the communication demand index of each link node in the target time window is calculated, and the joint priority index of each link node in the target time window is calculated. The acquisition diagram of the joint priority index is as shown in Figure 2

[0056] By calculating the joint priority index of each link node, the priority of each link node is obtained, and the bandwidth allocation proportion is divided for the link nodes with higher priority. The obtained joint priority index is used as the weight of each link node, and the total transmission bandwidth and the weight of each link node are used as the input, and the weighted maximum minimum fairness algorithm is used for bandwidth allocation, and the allocated bandwidth of each link node is output. The weighted maximum minimum fairness algorithm is a known technology, and the detailed operation process will not be described in detail. Dynamic bandwidth allocation is performed on each link node.

[0057] In each link node, the priority of data transmission is different due to the different timeliness of different data. Considering that the timeliness of industrial internet data is strong, first, the IEEE 802.1p protocol is used to mark the priority (0-7) of each data flow in the VLAN tag. The switch uses the joint demand index calculation method, based on the transmission of each data flow in each link node, to obtain the joint demand index of each data flow, and to multiply the joint demand index of each data flow by the priority of the data flow as the weight of each data flow. The weighted maximum minimum fairness algorithm is used to allocate bandwidth to each data flow in each link node for real-time transmission.

[0058] The fourth step is to integrate the transmitted industrial internet data.

[0059] ​The data of each link node is transmitted to a central data platform, the data obtained by the central data platform is integrated by using an open source ETL tool Talend, data filtering, format conversion, field mapping and exception handling are performed on the obtained data by using components such as tMap, and data quality is further ensured; data aggregation and grouping calculation (such as device mean value, alarm statistics, etc.) are realized by using tMemorizeRows, then storage is realized by using components such as tDBOutput, tHDFSOutput and tFileOutput, the processed industrial data is persisted to a target system, and accessibility and analysis availability are ensured. Finally, Talend Scheduler is used to run a Job at a timing, and the task state and log are monitored in Talend Admin Center, data is pushed to a downstream business system or a visual large screen or a mobile terminal application by using tRESTClient or an enterprise service bus, and integrated processing of industrial internet data is realized.

[0060] Based on the same inventive concept as the above method, the embodiments of the present application also provide an industrial internet data integrated processing system, comprising a memory, a processor and a computer program stored in the memory and running on the processor, and the processor implements the steps of any one of the above industrial internet data integrated processing methods when executing the computer program.

[0061] The flowcharts and block diagrams in the drawings show the possible implementation architecture, function and operation of the system, method and computer program product according to the embodiments of the present application. In this regard, each block in the flowcharts or block diagrams can represent a module, a program segment or a part of code containing one or more executable instructions for implementing a specified logic function. In some alternative implementations, the functions annotated in the blocks can also occur in an order different from that annotated in the drawings. For example, two consecutive blocks can actually be executed substantially in parallel, and sometimes they can also be executed in reverse order, depending on the functions involved. In the description corresponding to the flowcharts and block diagrams in the drawings, the operations or steps corresponding to different blocks can also occur in an order different from that disclosed in the description, and sometimes there is no specific order between different operations or steps. For example, two consecutive operations or steps can actually be executed substantially in parallel, and sometimes they can also be executed in reverse order, depending on the functions involved. Each block in the block diagram and / or flowchart, and the combination of blocks in the block diagram and / or flowchart, can be implemented by a dedicated hardware-based system performing the specified functions or actions, or can be implemented by a combination of dedicated hardware and computer instructions.

[0062] It is apparent for a person skilled in the art that the present application is not limited to the details of the above-described exemplary embodiments, but can be implemented in other concrete forms without departing from the essential characteristics of the present application. Therefore, the above-described embodiments of the present application should be considered in all respects as illustrative and not restrictive; the modifications made to the technical solutions described in the above-described embodiments, or the equivalent replacements of some of the technical features, do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application.

Claims

1. A method for integrated processing of industrial internet data, characterized in that, The method includes the following steps: Extract various transmission data from each link node in the Industrial Internet; Preset a time window, analyze the degree of bandwidth impact of the target time window on the previous time windows, and determine the probability weight of bandwidth impact for each time window before the target time window; analyze the phenomenon that data transmission anomalies occur multiple times in each time window before the target time window for each link node, and combine the number of data retransmissions to determine the comprehensive impact index of each link node in each time window before the target time window. Analyze the transmission anomalies of each link node in each time window before the target time window, and combine the comprehensive impact index and bandwidth impact probability weight to determine the joint priority index of each link node in the target time window, and divide the bandwidth allocation ratio of the link nodes; obtain the joint priority index of each type of transmission data on each link node after division, and combine the priority of each type of transmission data to allocate bandwidth for each type of transmission data. Integrate and process the industrial internet data that has been transmitted; The determination of the comprehensive impact index of each link node in each time window before the target time window is specifically as follows: Data is transmitted in the form of data packets; the single retry invalidity coefficient is determined based on the number of data packets that still fail to retransmit after the first retransmission in each time window before the target time window for each link node; The negative correlation mapping of the number of retransmissions of each failed data packet is used as the index of the single retry ineffectiveness. The sum of the normalized values ​​of the index results obtained from all failed data packets is used as the comprehensive impact index of each link node in each time window before the target time window.

2. The industrial internet data integration processing method as described in claim 1, characterized in that, The bandwidth influence probability weight for each time window prior to determining the target time window is specifically as follows: Number the preset number of consecutive time windows preceding the target time window; The negative correlation mapping result of the ratio of the number of each time window before the target time window to the preset number is used as the bandwidth influence probability weight of each time window before the target window.

3. The industrial internet data integration processing method as described in claim 1, characterized in that, The single retry invalidity coefficient is specifically defined as the percentage of data packets that fail to retransmit after the first retransmission within each time window before the target time window for each link node.

4. The industrial internet data integration processing method as described in claim 1, characterized in that, The determination of the joint priority index for each link node within the target time window specifically involves: Analyze the number of abnormal data packets transmitted by each link node in each time window before the target time window to determine the link congestion rate; Based on the link congestion rate and the comprehensive impact index, the transmission impact index is determined; The bandwidth impact probability weight percentage of each link node in each time window before the target time window is calculated and used as the weight of the transmission impact index. The weighted sum is then used to obtain the communication demand index of each link node in the target time window. The percentage of each link node's communication demand metrics within the target time window is used as the joint priority metric for each link node within the target time window.

5. The industrial internet data integration processing method as described in claim 4, characterized in that, The link congestion rate is specifically defined as the percentage of data packets that experience transmission failures or timeouts within each time window prior to the target time window for each link node.

6. The industrial internet data integration processing method as described in claim 4, characterized in that, The specific transmission impact indicator is the product of the link congestion rate and the comprehensive impact indicator.

7. The industrial internet data integration processing method as described in claim 1, characterized in that, The specific process of allocating bandwidth to link nodes is as follows: The joint priority index is used as the weight of each link node. Combined with the total transmission bandwidth, a resource allocation algorithm is used to allocate bandwidth to obtain the allocated bandwidth for each link node.

8. The industrial internet data integration processing method as described in claim 1, characterized in that, The process of allocating bandwidth for each type of transmitted data is as follows: The joint demand index for each type of data is multiplied by its corresponding priority to obtain the weight of each type of transmitted data. Combined with the allocated bandwidth of each link node, a resource allocation algorithm is used to obtain the allocated bandwidth of each type of transmitted data at each link node.

9. An industrial internet data integration processing system, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the method as described in any one of claims 1-8.

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