Automatic updating method and device for rail transit vehicle-mounted safety platform and medium

Abstract

The invention relates to an automatic updating method and device for a rail transit vehicle-mounted safety platform and a medium, and the method is realized based on a host machine for storing a file to be updated and a vehicle-mounted safety platform board card needing to be updated. The method comprises an automatic updating processing process of a host machine and an automatic updating processing process of a board card management controller BMC on each board card of the vehicle-mounted safety platform. Compared with the prior art, the method has the advantages that the updating operation is convenient, the configuration is flexible, the updating process is controllable, and the error probability possibly introduced by manual operation is reduced.

Description

Technical Field

[0001] The present invention relates to a rail transit signal system, and in particular to an automatic update method, device and medium for an on-vehicle safety platform of rail transit. Background Art

[0002] In a rail transit vehicle operation control system, an Automatic Train Protection (ATP) system and an Automatic Train Operation (ATO) system both run on an on-vehicle safety platform. These systems are often composed of numerous boards with different functions, and the number of boards is very large. In the past, when upgrading the version or updating configuration data of the on-vehicle safety platform, it was generally necessary to manually perform item-by-item burning and updating operations, and the steps were rather cumbersome. In an actual operating system, the number of vehicles is often very large. There may be dozens or hundreds of trains on a line. If all are updated item-by-item manually, the labor and time costs for updating and upgrading will be relatively high, and the steps are numerous.

[0003] The following problems generally exist in the existing update of the rail transit on-vehicle safety platform:

[0004] 1) The update steps are cumbersome: In an actual operating system, the number of vehicles is often very large. There may be dozens or hundreds of trains on a line. If all are updated item-by-item manually, the labor and time costs for updating and upgrading will be relatively high, the steps are numerous, and there is also a possibility of introducing errors during the burning process due to manual operation.

[0005] 2) When an on-vehicle device only has a device bus and no functions such as FTP and TFTP, the download and update process lacks a certain degree of controllability. If the receiving and processing speed of the board does not match that of the host computer, it is easy to have a situation where the receiving buffer is full and subsequent data cannot be received, resulting in an update failure.

[0006] Therefore, how to simplify the burning steps, reduce the time cost, labor cost and maintenance difficulty of system maintenance, and improve the controllability of the burning and updating process, and reduce the probability of introducing errors caused by manual operation is a technical problem to be solved. Summary of the Invention

[0007] The purpose of the present invention is to overcome the above-mentioned defects existing in the prior art and provide an automatic update method, device and medium for a rail transit on-vehicle safety platform with convenient update operation, controllable update process, and reduced probability of errors introduced by human operation.

[0008] The purpose of the present invention can be achieved by the following technical solutions:

[0009] According to the first aspect of the present invention, an automatic update method for an on-vehicle safety platform of rail transit is provided. This method is implemented based on a host computer storing files to be updated and a board of the on-vehicle safety platform that needs to be updated. The method includes the automatic update processing process of the host computer and the automatic update processing process of the board management controller (BMC) on each board of the on-vehicle safety platform.

[0010] As a preferred technical solution, each message between the host computer and the board BMC includes an SFID field and a data part with a maximum of N bytes. The SFID field is used to distinguish message types.

[0011] As a preferred technical solution, the automatic update processing process of the host computer specifically includes the following steps:

[0012] Step S101, the host computer sends a board scan message MSG_Scan to the BMCs of each board of the on-vehicle safety platform;

[0013] Step S102, after the host computer receives the scan reply message MSG_Scan_ACK from the board BMC, it sends a download request message MSG_Download_Req to the board BMC;

[0014] Step S103, after the host computer receives the download start message MSG_Download_SOF from a certain board BMC, it starts to send download data messages MSG_Download_Data to the board BMC;

[0015] Step S104, if the host computer receives a download pause message MSG_Download_IOF from a certain board BMC, it pauses sending the download data message MSG_Download_Data to the board BMC;

[0016] Step S105, if the host computer receives a download resume message MSG_Download_COF from a certain board BMC while pausing to send data to the board BMC, it starts to send the download data message MSG_Download_Data to the board BMC from the file offset position pointed to in the resume message;

[0017] Step S106, after the host computer finishes sending the download data message MSG_Download_Data, it sends a download end message MSG_Download_EOF to the corresponding board BMC once;

[0018] Step S107, when receiving the download complete message MSG_Download_Comp from a certain board BMC, it means that a download update operation is completed.

[0019] As a preferred technical solution, the download request message MSG_Download_Req in step S102 includes the following content:

[0020] 1) The length of the file to be downloaded; 2) The type of flash to which the downloaded file is to be downloaded; 3) The type of the board to be updated; 4) The offset address to be written to the flash.

[0021] As a preferred technical solution, the download data message MSG_Download_Data in step S103 includes:

[0022] Data transmission is split and transmitted according to large packets and small packets. One small packet is one message. M bits in the SFID are used to represent the small packet sequence number. One large packet consists of 2^M small packets;

[0023] The header of the first small packet in each large packet is the large packet sequence number and the check code of the large packet. Except for this header, all other data in the large packet is the content of the file to be updated.

[0024] As a preferred technical solution, the automatic update processing procedure of the board management controller BMC on each board of the vehicle-mounted safety platform specifically includes the following steps:

[0025] Step S201, after the board BMC receives the board scan information MSG_Scan from the host computer, it sends a scan reply message MSG_Scan_ACK to the host computer;

[0026] Step S202, after the board BMC receives the download request message MSG_Download_Req from the host computer, it sends a download start message MSG_Download_SOF to the host computer;

[0027] Step S203, after the board BMC receives the download data message MSG_Download_Data from the host computer, it temporarily stores the received data in the data buffer, and performs verification and flash writing operations after receiving a complete large packet;

[0028] Step S204, if the message queue for the board BMC to receive the download data message MSG_Download_Data is full, it sends a download pause message MSG_Download_IOF to the host computer to interrupt the download transmission;

[0029] Step S205, if the board BMC finishes processing the messages in the message queue after sending the download pause message MSG_Download_IOF, it sends a download resume message MSG_Download_COF to the host computer to continue the download transmission;

[0030] Step S206: After the board card BMC receives the download end message MSG_Download_EOF from the host computer, it sends a download completion message MSG_Download_Comp to the host computer to complete a download and update operation.

[0031] As a preferred technical solution, the scan reply message MSG_Scan_ACK in the step S201 includes the following contents:

[0032] 1) The type of this board card; 2) The slot number of this board card in the chassis.

[0033] As a preferred technical solution, the download start message MSG_Download_SOF in the step S202 includes the following contents:

[0034] 1) The type of this board card; 2) The flash type to be updated on this board card.

[0035] As a preferred technical solution, the specific operation of performing verification and writing to the flash after receiving a large packet in the step S203 is as follows:

[0036] Calculate the verification code for the large packet data in the data buffer. If the calculated verification code is the same as the verification code carried by the first small packet in the large packet, the large packet passes the verification, and the large packet data is written to the corresponding position of the flash of the board card;

[0037] If the calculated verification code is different from the verification code carried by the first small packet in the large packet, the large packet fails the verification. The board card BMC first sends a download pause message MSG_Download_IOF to the host computer, and then sends a download resume message MSG_Download_COF, where the serial number of the large packet to be resumed is the serial number of the large packet that fails the current verification, and waits for the host computer to resend the large packet data.

[0038] As a preferred technical solution, the download resume message MSG_Download_COF in the step S205 includes the following contents:

[0039] 1) The type of this board card; 2) The flash type to be updated on this board card; 3) The serial number of the large packet to be resumed currently.

[0040] 11. According to the automatic update method for a rail transit vehicle-mounted safety platform described in claim 6, it is characterized in that the download completion message MSG_Download_Comp in the step S206 includes the following contents:

[0041] 1) The type of this board card; 2) The type of flash updated for this board card this time; 3) The check code calculated after the update of this board card is completed this time; 4) The file check flag.

[0042] According to a second aspect of the present invention, there is provided an electronic device, including a memory and a processor. A computer program is stored on the memory, and when the processor executes the program, the method described above is implemented.

[0043] According to a third aspect of the present invention, there is provided a computer-readable storage medium, on which a computer program is stored, and when the program is executed by a processor, the method described above is implemented.

[0044] Compared with the prior art, the present invention has the following advantages:

[0045] 1) The present invention only requires a single host computer to be connected to the chassis of the vehicle-mounted safety platform. By differentiating the board card type and slot information of each board card through the messages between the host computer and the board card BMC, all the board cards in the chassis can be updated, avoiding the large number of cumbersome operations caused by different types of board cards during the previous manual item-by-item update. The update operation is convenient, reducing the time cost and labor cost.

[0046] 2) The present invention is updated through the board card BMC. Therefore, as long as the board cards to be updated in the configuration are inserted into the chassis, it is not required that board cards such as the MPU logic board card must be in the system, having a certain degree of flexibility in the update configuration.

[0047] 3) During the update process of the present invention, the board card BMC controls the progress of the download update according to the correctness of the received download data packet and the message queue status, avoiding the problem of update failure caused by the mismatch between the performance of the board card BMC and the host computer, making the download update process controllable.

[0048] 4) The update and burning operation of the present invention is completed by the cooperation of the host computer and the board card BMC, minimizing the degree of manual operation participation and reducing the error probability that may be caused by manual burning. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 It is a schematic diagram of the communication between the host computer and the board card BMC of the vehicle-mounted safety platform in the present invention;

[0050] Figure 2 It is a schematic diagram of the process of automatic update message interaction in the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0051] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0052] The prior art has the following problems: The in-vehicle safety platform has complex functions and a large number of board types and quantities. If updated item by item manually, the operation is complex and cumbersome, with high time and labor costs, and there is also a certain possibility of errors during manual update. The present invention aims to provide a method to solve the above problems, realizing a unified update processing method through BMC on various board devices, simplifying the operation of burning and updating; controlling the transmission speed of the host computer through download pause messages and download resume messages to improve the controllability of the download update process and the success rate of the update.

[0053] This embodiment relates to an automatic update method for an in-vehicle safety platform. This method is implemented based on the rail transit in-vehicle safety platform. Since the in-vehicle safety platform has complex functions, there are a large number of board types and quantities in the platform. Through the communication between the host computer and the board BMC, the files to be updated can be sent to the board BMC to be updated according to the number and type of boards in the in-vehicle safety platform, and the board BMC writes the data into the corresponding flash, realizing the automatic update of the files in the board, reducing the complexity of the operation and the error probability during the update.

[0054] Figure 1 It is a schematic diagram of the communication between the host computer and the board BMC of the in-vehicle safety platform in the present invention. As Figure 1 shown,

[0055] (1) The host computer stores the files to be updated and the configuration files related to the automatic update. The configuration files contain the number of boards to be updated, board types, slot information, names, sizes, flash types, and offset address information of the files to be updated.

[0056] (2) The host computer is connected to the chassis of the in-vehicle safety platform through a network. After the network message reaches the chassis, it is converted into a bus message and broadcast among the boards in the chassis. The board BMC performs corresponding update processing operations according to the received messages.

[0057] As Figure 2 shown, the automatic update operation of the rail transit in-vehicle safety platform consists of message interactions between the host computer and the board BMC. The specific process is as follows:

[0058] Scanning stage:

[0059] Step S0101: The host loads the configuration file and obtains information such as the number of boards to be updated this time, board types, slot information, flash types, number of files, offset addresses of each file, etc.

[0060] Step S0102: The host sends the board scan information MSG_Scan to the board BMC and waits to receive the scan reply message MSG_Scan_ACK from each board BMC.

[0061] Step S0103: After receiving the board scan information MSG_Scan sent by the host, each board BMC sends the scan reply message MSG_Scan_ACK to the host.

[0062] Step S0104: After the host receives the scan reply message MSG_Scan_ACK sent by each board BMC, it can confirm the number, types, and slot information of the boards in the current chassis.

[0063] Connection establishment phase:

[0064] Step S0201: The host sends the download request message MSG_Download_Req to a specified board BMC and waits for the board BMC to reply with the download start message MSG_Download_SOF. The download request message contains information such as the target board type, flash type, and offset address to be updated.

[0065] Step S0202: After receiving the download request message MSG_Download_Req from the host, the board BMC sends the download start message MSG_Download_SOF to the host.

[0066] Step S0203: The host receives the download start message MSG_Download_SOF replied by the board BMC and prepares to enter the data transfer phase.

[0067] Data transfer phase:

[0068] Step S0301: The host sends the download data message MSG_Download_Data to the above board BMC. The data transfer is split and transmitted according to the large packet - small packet hierarchy. One small packet is a message, and M bits in the SFID are used to represent the small packet sequence number. One large packet consists of 2^M small packets. The header of the first small packet in each large packet is the large packet sequence number and the checksum of the large packet. Except for this header, the other data parts in the large packet are all the content of the file to be updated.

[0069] Step S0302: After the board card BMC receives the download data message MSG_Download_Data, it temporarily stores the received data in the buffer, and after a large packet is received in the buffer, the following verification is performed: Calculate the verification code according to the content of the large packet data. If it is consistent with the verification code sent by the host, the large packet passes the verification, and the large packet data is written to the corresponding address in the corresponding flash type of the board card; if it is inconsistent with the verification code sent by the host, the large packet fails the verification. The board card BMC first sends a download pause message MSG_Download_IOF to the host, and then sends a download resume message MSG_Download_COF to notify the host to retransmit the large packet.

[0070] Step S0303: In the data transmission stage, if the processing capabilities of the board card BMC and the host cannot match, the transmission steps are controlled in the following way:

[0071] If the message queue for the board card BMC to receive the download data message MSG_Download_Data is full, the board card BMC sends a download pause message MSG_Download_IOF to the host to notify the host to pause sending.

[0072] If the board card BMC finishes processing the messages in the message queue after sending the download pause message MSG_Download_IOF, it sends a download resume message MSG_Download_COF to the host to continue the download transmission.

[0073] If the host receives the download pause message MSG_Download_IOF sent by the board card BMC, it pauses sending the download data message MSG_Download_Data and waits to continue sending from the large packet sequence number in the resume message after receiving the download resume message MSG_Download_COF sent by the board card BMC.

[0074] Transmission end stage:

[0075] Step S0401: After the host finishes sending the download data message MSG_Download_Data of the current file, it sends a download end message MSG_Download_EOF to the board card BMC.

[0076] Step S0402: After the board card BMC receives the download end message MSG_Download_EOF sent by the host, it sends a download complete message MSG_Download_Comp to the host, and this update ends.

[0077] The connection establishment phase, data transmission phase, and transmission end phase constitute the update process of a file in a board. For the files to be updated on each board in the chassis, the update process is sequentially executed according to the order of the configuration files in the host computer, and the automatic update operation of all the boards to be updated in the chassis can be completed.

[0078] In summary, in this embodiment on the rail transit vehicle-mounted safety platform, through the communication between the board BMC and the host computer, the host computer obtains the information of all the boards in the current chassis during the scanning phase. Then, for the boards that need to be updated, each board and each image are updated one by one according to the connection establishment - data transmission - transmission end, and the file update of all the boards to be updated in the chassis is completed. Through the unified flash update operation, the problems that the burning methods of different types of files such as CPU software images, FPGA logic images, and configuration data files are different in the past are avoided, the manual operations during the update are reduced, the labor cost and time cost of the update are reduced, and it is more convenient and fast. It can be freely configured according to the boards that need to be updated, and has a certain degree of flexibility. By the board BMC sending the download pause message (MSG_Download_IOF) and download resume message (MSG_Download_COF) to the host computer, the update download progress can be controlled according to the actual situation during the update, and the transmission is more controllable. By setting the information of the boards to be updated through the configuration file on the host computer, the error probability that may be introduced by the previous manual item-by-item burning update is further reduced.

[0079] The above is the introduction of the method embodiment. The following further illustrates the solution of the present invention through the embodiments of the electronic device and the storage medium.

[0080] The embodiment of the present invention further provides an electronic device including a central processing unit (CPU), which can execute various appropriate actions and processes according to the computer program instructions stored in the read-only memory (ROM) or the computer program instructions loaded from the storage unit to the random access memory (RAM). In the RAM, various programs and data required for device operation can also be stored. The CPU, ROM, and RAM are connected to each other through a bus. The input / output (I / O) interface is also connected to the bus.

[0081] Multiple components in the device are connected to the I / O interface, including: an input unit, such as a keyboard, a mouse, etc.; an output unit, such as various types of displays, speakers, etc.; a storage unit, such as a disk, an optical disc, etc.; and a communication unit, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit allows the device to exchange information / data with other devices through a computer network such as the Internet and / or various telecommunication networks.

[0082] The processing unit executes the various methods and processes described above, such as the method of the present invention. For example, in some embodiments, the method of the present invention may be implemented as a computer software program tangibly embodied in a machine-readable medium, such as a storage unit. In some embodiments, part or all of the computer program may be loaded and / or installed onto the device via the ROM and / or the communication unit. When the computer program is loaded into the RAM and executed by the CPU, one or more steps of the method of the present invention described above may be performed. Alternatively, in other embodiments, the CPU may be configured to execute the method of the present invention by any other suitable means (e.g., by means of firmware).

[0083] The functions described above herein may be performed at least in part by one or more hardware logic components. By way of example and not limitation, exemplary types of hardware logic components that may be used include: field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), systems on a chip (SOCs), complex programmable logic devices (CPLDs), and the like.

[0084] The program code for implementing the method of the present invention may be written in any combination of one or more programming languages. These program codes may be provided to a processor or controller of a general purpose computer, a special purpose computer, or other programmable data processing device, such that the program codes, when executed by the processor or controller, cause the functions / operations specified in the flowchart and / or block diagram to be implemented. The program code may be executed entirely on the machine, partly on the machine, as a stand-alone software package partly on the machine and partly on a remote machine, or entirely on the remote machine or server.

[0085] In the context of the present invention, a machine-readable medium may be a tangible medium that can contain or store a program for use by or in connection with an instruction execution system, apparatus, or device. A machine-readable medium may be a machine-readable signal medium or a machine-readable storage medium. A machine-readable medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination of the foregoing. More specific examples of a machine-readable storage medium would include an electrical connection based on one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0086] As described above, it is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of various equivalent modifications or substitutions, and these modifications or substitutions should all be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. An automatic update method for a rail transit vehicle safety platform, characterized in that: The method is implemented based on a host machine storing files to be updated and a vehicle safety platform board that needs to be updated. The method includes an automatic update processing process of the host machine and an automatic update processing process of a board management controller BMC on each board of the vehicle safety platform.

2. The automatic updating method for a rail transit vehicle safety platform according to claim 1, characterized in that: Each message between the host machine and the board BMC includes a SFID field and a data portion with a maximum length of N bytes. The SFID field is used to distinguish message types.

3. The automatic updating method for a rail transit vehicle safety platform according to claim 1, characterized in that: The automatic update process of the host machine specifically includes the following steps: Step S101, the host sends board scan information MSG_Scan to each board BMC of the vehicle safety platform; Step S102, after receiving the scan reply message MSG_Scan_ACK from the board BMC, the host sends a download request message MSG_Download_Req to the board BMC; Step S103, after receiving the download start message MSG_Download_SOF from a board BMC, the host starts to send a download data message MSG_Download_Data to the board BMC; Step S104, if the host machine receives a download pause message MSG_Download_IOF from a board BMC, it stops sending download data message MSG_Download_Data to the board BMC; Step S105, if the host machine receives a download resume message MSG_Download_COF from a board BMC while pausing to send data to the board BMC, it continues to send download data messages MSG_Download_Data to the board BMC starting from the file offset position pointed to in the resume message; Step S106, after the host completes sending the download data message MSG_Download_Data, it sends a download end message MSG_Download_EOF to the corresponding board BMC; Step S107, receiving a download completion message MSG_Download_Comp from a board BMC, which means that a download update operation is completed.

4. According to claim 3, the automatic update method for a rail transit vehicle safety platform is characterized in that: The download request message MSG_Download_Req in step S102 includes the following contents: 1) The length of the file to be downloaded; 2) The type of flash to which the file is to be downloaded; 3) The type of the board to be updated; 4) The offset address to be written into the flash.

5. The automatic updating method for a rail transit vehicle safety platform according to claim 3 is characterized in that: The download data message MSG_Download_Data in step S103 includes: Data transmission is split into large packets and small packets. A small packet is a message. The M bits in the SFID are used to indicate the small packet sequence number. A large packet consists of 2^M small packets. The header of the first small packet in each large packet is the large packet sequence number and the check code of the large packet. Except for the header, all other data in the large packet are the contents of the file to be updated.

6. The automatic updating method for a rail transit vehicle safety platform according to claim 1, characterized in that: The automatic update process of the board management controller BMC on each board of the vehicle safety platform specifically includes the following steps: Step S201, after receiving the board scan information MSG_Scan from the host, the board BMC sends a scan reply message MSG_Scan_ACK to the host; Step S202, after receiving the download request message MSG_Download_Req from the host machine, the board BMC sends a download start message MSG_Download_SOF to the host machine; Step S203, after receiving the download data message MSG_Download_Data from the host machine, the board BMC temporarily stores the received data in the data buffer, and performs verification and flash writing operations after receiving a large package; Step S204, if the message queue of the board BMC receiving the download data message MSG_Download_Data is full, a download pause message MSG_Download_IOF is sent to the host machine to interrupt the download transmission; Step S205, if the board BMC completes processing the messages in the message queue after sending the download pause message MSG_Download_IOF, it sends a download resume message MSG_Download_COF to the host machine to continue download transmission; Step S206, after receiving the download end message MSG_Download_EOF from the host machine, the board BMC sends a download completion message MSG_Download_Comp to the host machine, completing a download update operation.

7. The automatic updating method for a rail transit vehicle safety platform according to claim 6, characterized in that: The scan reply message MSG_Scan_ACK in step S201 includes the following contents: 1) The type of this board; 2) The slot number of this board in the cage.

8. The automatic updating method for a rail transit vehicle safety platform according to claim 6, characterized in that: The download start message MSG_Download_SOF in step S202 includes the following contents: 1) The type of this board; 2) The type of flash to be updated on this board.

9. The automatic updating method for a rail transit vehicle safety platform according to claim 6, characterized in that: In step S203, after a large packet is collected, the verification and flash writing operations are specifically as follows: Calculate the check code for the large packet data in the data buffer. If the calculated check code is consistent with the check code of the first small packet in the large packet, the large packet passes the check and the large packet data is written to the corresponding position of the corresponding flash of the board. If the calculated check code is inconsistent with the check code of the first small packet in the large packet, the large packet fails the check. The board BMC first sends a download pause message MSG_Download_IOF to the host, and then sends a download resume message MSG_Download_COF, in which the sequence number of the large packet to be resumed is the sequence number of the large packet that failed the current check, waiting for the host to resend the large packet data.

10. The automatic updating method for a rail transit vehicle safety platform according to claim 6, characterized in that: The download resume message MSG_Download_COF in step S205 includes the following contents: 1) The type of this board; 2) The type of flash to be updated on this board; 3) The sequence number of the large packet to be continued.

11. The automatic updating method for a rail transit vehicle safety platform according to claim 6, characterized in that: The download completion message MSG_Download_Comp in step S206 includes the following contents: 1) The type of this board; 2) The flash type of this board updated; 3) The checksum calculated after the board is updated; 4) The file checksum mark.

12. An electronic device comprising a memory and a processor, wherein a computer program is stored in the memory, wherein: When the processor executes the program, the method according to any one of claims 1 to 11 is implemented.

13. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the method according to any one of claims 1 to 11 is implemented.

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