Nuclear power plant misstep prevention interval and operational verification system and method

Abstract

This disclosure belongs to the field of nuclear power technology, specifically relating to a nuclear power plant error prevention interval and operation verification system and method. The nuclear power plant error prevention interval and operation verification system provided in this disclosure constructs a three-dimensional, intelligent error prevention system with "proactive early warning, real-time verification, and mandatory compliance" through a server, multiple sensing and positioning subsystems, multiple intelligent terminals, and a back-end monitoring center. It can achieve both spatial verification, ensuring that personnel enter and remain within authorized work areas, and object verification, ensuring that the equipment prepared for operation by personnel is completely consistent with the work order instructions. The linked verification results of spatial and object verification serve as prerequisites for the continued execution of procedural tasks, achieving mandatory process control.

Description

Technical Field

[0001] This invention belongs to the field of nuclear power technology, specifically relating to a nuclear power plant anti-misoperation bay and operation verification system and method. Background Technology

[0002] In the complex, densely packed, and highly hazardous industrial environment of nuclear power plants, "going to the wrong bay" and "operating the wrong equipment" are typical and serious human errors. Existing protective measures generally have the following deficiencies: Relying on staff self-awareness and memory: It mainly relies on staff's memory of routes, recognition of signs, and management procedures such as "three-way communication," which are prone to failure under fatigue, stress, or emergency situations.

[0003] Regulatory measures are passive and lagging: Traditional supervisory inspections or camera monitoring are post-event supervisions that cannot intervene in a timely manner when wrongdoing occurs.

[0004] The signage system may have limitations: in low light conditions, when the signs are dirty, or when the equipment looks very similar, visual identification alone is extremely risky.

[0005] Electronic processes are disconnected from the physical world: Existing electronic work package systems can inform you of the operation content, but cannot verify in the physical space whether "the person is in the correct position" and "the hands are operating the correct equipment".

[0006] Lack of technical error prevention barriers: The existing system lacks an automated, mandatory technical error prevention barrier to completely shield human error before it occurs.

[0007] While single positioning or identification technologies are relatively mature, existing solutions have failed to deeply integrate them with core business processes. The core problem this invention aims to solve is: how to creatively bind and verify spatial location information and device identity information in real time at the business execution level, constructing a proactive security protection system that links "digital and physical" spaces, thereby achieving an intrinsic security improvement from "human-based" to "technology-based" security. Summary of the Invention

[0008] To overcome the problems existing in related technologies, a nuclear power plant anti-misguided bay and operation verification system and method are provided.

[0009] According to one aspect of the present disclosure, a nuclear power plant anti-misguided interval and operation verification system is provided, the system comprising: a server, multiple sensing and positioning subsystems, multiple smart terminals and a background monitoring center; The server constructs a 3D digital map based on the factory's map or model; for the received maintenance work order or operation task, it delineates a corresponding dynamic electronic fence on the digital map, which corresponds to the physical space range of the equipment associated with the maintenance work order or operation task; the server also sends the received maintenance work order or operation task to the associated smart terminal. Multiple sensing and positioning subsystems are deployed in the operation and maintenance area of ​​a nuclear power plant. Each sensing and positioning subsystem is used to locate smart terminals that appear within a preset range and send the location data of the smart terminal to the smart terminal and the server. The smart terminal has built-in positioning tags, cameras, and communication modules that can communicate with various sensing and positioning subsystems; the smart terminal can obtain device information by scanning the tags on the device through the camera; Based on the maintenance work order or operation task corresponding to each smart terminal, as well as the current location data and the scanned device information, the server determines whether the maintenance personnel holding the smart terminal have gone to the wrong place or made a mistake. When it is determined that the maintenance personnel holding the smart terminal have gone to the wrong place or made a mistake, the server controls the smart terminal and the back-end monitoring center to execute the corresponding prompts.

[0010] In one possible implementation, the server records the entire process of the operation and maintenance personnel holding the smart terminal, including their movement trajectory, verification time, device code, and operation results, forming a security audit log.

[0011] In one possible implementation, each smart terminal's interactive interface can intuitively display the electronic fence, the smart terminal's real-time location, the device scanning interface, verification results, and alarm information.

[0012] In one possible implementation, the display screen in the back-end monitoring center can provide a global view of the nuclear power plant's operation and maintenance area, displaying the location, working status, electronic fence distribution, and alarm information of all smart terminals in real time.

[0013] In one possible implementation, the sensing and positioning subsystem includes a UWB positioning system and a 5G indoor positioning system, with the UWB positioning system and the 5G indoor positioning system being deployed in a mixed manner in the nuclear power plant operation and maintenance area.

[0014] In one possible implementation, the smart terminal includes explosion-proof mobile phones, PDAs, and smart safety helmets.

[0015] In one possible implementation, the smart terminal also integrates an OCR engine. When the label is blurry or damaged, making it impossible for the smart terminal to recognize the label, the smart terminal can call the OCR engine to directly recognize the device code and name on the nameplate.

[0016] According to one aspect of the present disclosure, a method for preventing runaway operations and verifying operations in a nuclear power plant is provided. The method is implemented based on the system of any one of claims 1 to 7, and includes: Step 100, Task Binding and Fence Delineation: The server creates an electronic fence based on the received maintenance work order or operation task, and binds the device code associated with the maintenance work order or operation task within the electronic fence. Step 101, First verification: The server receives location data from smart terminals of various sensing and positioning subsystems in real time and determines whether the location data of each smart terminal is within the associated electronic fence range. If the location data of a smart terminal is within the associated electronic fence range, an instruction is sent to the smart terminal to execute a first prompt, indicating that the person holding the smart terminal has entered the work area. If the location data of a smart terminal exceeds the associated electronic fence range, an instruction is sent to the smart terminal and the back-end monitoring center to execute a second prompt, indicating that the person holding the smart terminal has deviated from or mistakenly entered an unauthorized area. Step 102, Second Verification: When a repair work order or operation task is triggered on the smart terminal, the smart terminal temporarily locks the execution flow of the repair work order or operation task and performs a device identification scan. After identifying the device information, the smart terminal determines whether the device information corresponding to the currently executed repair work order or operation task is consistent with the identified device information. If the device information corresponding to the currently executed repair work order or operation task is consistent with the identified device information, a third prompt is executed to indicate that the device verification is correct and the repair work order or operation task is unlocked, allowing the repair work order or operation task to continue execution. If the device information corresponding to the currently executed repair work order or operation task is inconsistent with the identified device information, a fourth prompt is executed to indicate that the device verification is incorrect and the repair work order or operation task remains locked.

[0017] In one possible implementation, the method further includes: step 103, generating audit logs, whereby the server records personnel trajectories, verification times, device codes, and operation results throughout the process, forming a security audit log.

[0018] According to another aspect of the present disclosure, a non-volatile computer-readable storage medium is provided, on which computer program instructions are stored, which, when executed by a processor, implement the above-described method.

[0019] The beneficial effects of this disclosure are as follows: The nuclear power plant anti-misoperation bay and operation verification system provided by this disclosure constructs a three-dimensional, intelligent anti-human error system through a server, multiple sensing and positioning subsystems, multiple intelligent terminals, and a back-end monitoring center, featuring "proactive early warning, real-time verification, and mandatory compliance." It can achieve both spatial verification, ensuring that personnel enter and remain within authorized work areas, and object verification, ensuring that the equipment prepared for operation by personnel is completely consistent with the work order instructions. The linked verification results of spatial and object verification serve as a prerequisite for the continued execution of procedural tasks, achieving mandatory process control. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of a nuclear power plant anti-misguided interval and operation verification system shown in an embodiment of this disclosure.

[0021] Figure 2 This is a flowchart illustrating a method for preventing misoperation and verifying operation in a nuclear power plant, as shown in an embodiment of this disclosure. Detailed Implementation

[0022] The present disclosure will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0023] Unless otherwise defined, the technical and scientific terms used in this disclosure have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains; the terminology used in this disclosure is for the purpose of describing particular embodiments only and is not intended to be limiting of this disclosure; the term "comprising" and any variations thereof in this disclosure are intended to cover non-exclusive inclusion. Clearly, the embodiments described in this disclosure are only a part of the embodiments of this disclosure, and not all of them. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of this disclosure without inventive effort are within the scope of protection of this disclosure.

[0024] In this disclosure, the reference to "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this disclosure. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0025] Figure 1 This is a schematic diagram of a nuclear power plant anti-misguided bay and operation verification system according to an embodiment of this disclosure, as shown below. Figure 1 As shown, the system includes: server 1, multiple sensing and positioning subsystems 2, multiple smart terminals 3, and a background monitoring center 4.

[0026] Server 1 constructs a 3D digital map based on the factory's BIM model or 2D map. For received maintenance work orders or operation tasks, it delineates corresponding dynamic electronic fences on the digital map. These electronic fences precisely correspond to the physical space of the equipment associated with the maintenance work order or operation task. Server 1 also sends the received maintenance work orders or operation tasks to the associated smart terminal 3.

[0027] Multiple sensing and positioning subsystems 2 are deployed in the nuclear power plant's operation and maintenance area (which may include, for example, the nuclear island area, conventional island area, and auxiliary facility area). Each sensing and positioning subsystem 2 corresponds to a detection area and is used to locate smart terminals 3 appearing within the corresponding detection area, and then send the location data of the smart terminal 3 to server 1. The sensing and positioning subsystems 2 can be, for example, UWB (Ultra-Wideband) positioning systems and / or 5G indoor positioning systems. The UWB positioning system provides ultra-high precision real-time positioning of 10-30 cm for communicating smart terminals 3 by deploying multiple UWB positioning base stations within a preset area. The UWB positioning system is applied to critical equipment areas with high precision requirements. The 5G indoor positioning system utilizes the high bandwidth and low latency characteristics of the 5G network, combined with algorithms such as TDOA and AOA, to achieve sub-meter (1-3 meter) positioning. It is suitable for large-area coverage and cost-sensitive areas. UWB positioning systems and 5G indoor positioning systems can be deployed in combination in the nuclear power plant's operation and maintenance area as needed.

[0028] The smart terminal 3 can be, for example, an explosion-proof mobile phone, a PDA, a smart safety helmet, or other terminals that are easy for workers to wear or hold. The smart terminal 3 has built-in positioning tags (such as UWB / 5G positioning tags), cameras, and Wi-Fi / 5G communication modules that can communicate with each sensing and positioning subsystem 2.

[0029] The smart terminal 3 can obtain device information by scanning the identification on the device using a camera. The device information includes the device code and name. The identification can be, for example, a QR code or a digital label. Furthermore, the smart terminal 3 also integrates an OCR (Optical Character Recognition) engine. If the identification is blurry or damaged, making it impossible for the smart terminal 3 to recognize the identification, the smart terminal 3 can call the OCR engine to directly recognize the device code and name on the label.

[0030] Server 1 performs dual verification on each smart terminal 3. The first verification is an anti-misdirection interval verification. Server 1 receives location data of smart terminals 3 from each sensing and positioning subsystem 2 in real time and determines whether the location data of each smart terminal 3 is within the associated electronic fence range. If the location data of smart terminal 3 is within the associated electronic fence range, a command is sent to smart terminal 3 to execute a first prompt, indicating that the person holding smart terminal 3 has entered the work area. If the location data of smart terminal 3 exceeds the associated electronic fence range, a command is sent to smart terminal 3 and the back-end monitoring center 4 to execute a second prompt, indicating that the person holding smart terminal 3 has deviated from or mistakenly entered an unauthorized area. The first and second prompts can be any one or more of text, voice, sound and light, and vibration.

[0031] The second layer of verification is to prevent accidental operation. When a maintenance work order or operation task on the smart terminal 3 is triggered (e.g., the maintenance work order or operation task entry on the smart terminal 3's interface is clicked "Start Execution"), the smart terminal 3 temporarily locks the execution flow of the maintenance work order or operation task (e.g., the relevant execution button is in an untriggerable state) and performs a device identification scan. After identifying the device information, the smart terminal 3 determines whether the device information corresponding to the currently executed maintenance work order or operation task is consistent with the identified device information. If the device information corresponding to the currently executed maintenance work order or operation task is consistent with the identified device information, a third prompt is executed to indicate that the device verification is correct, and the maintenance work order or operation task is unlocked, allowing the maintenance work order or operation task to continue execution. If the device information corresponding to the currently executed maintenance work order or operation task is inconsistent with the identified device information, a fourth prompt is executed to indicate that the device verification is incorrect, and the maintenance work order or operation task remains locked.

[0032] This disclosure establishes dual verification as a necessary prerequisite for executing critical steps in the procedural tasks. This effectively ensures the accuracy of the location and maintenance objects identified by maintenance personnel and provides timely reminders to them.

[0033] In one possible implementation, the server records the entire process of the operations and maintenance personnel holding the smart terminal, including their movement trajectory, verification time, device code, and operation results, forming a security audit log. By fully recording all verification operations, an unalterable security audit trail is created, ensuring full traceability of operations and maintenance activities.

[0034] Each smart terminal's interactive interface can intuitively display the electronic fence, the smart terminal's real-time location, the device scanning interface, verification results, and alarm information.

[0035] The display screen in the back-end monitoring center can provide safety management personnel with a global view of the nuclear power plant's operation and maintenance area, displaying the location, working status, electronic fence distribution, and alarm information of all smart terminals in real time, thus achieving transparent supervision.

[0036] Figure 2 This is a flowchart illustrating a nuclear power plant error prevention bay and operation verification method according to an embodiment of this disclosure. The method is implemented based on the aforementioned system, such as... Figure 2 As shown, the method includes: Step 100, Task Binding and Fence Delineation: The server creates an electronic fence based on the received maintenance work order or operation task, and binds the device code associated with the maintenance work order or operation task within the electronic fence.

[0037] Step 101, First verification: The server receives location data from the smart terminals of each sensing and positioning subsystem in real time and determines whether the location data of each smart terminal is within the associated electronic fence range. If the location data of the smart terminal is within the associated electronic fence range, an instruction is sent to the smart terminal to execute a first prompt, indicating that the person holding the smart terminal has entered the work area. If the location data of the smart terminal exceeds the associated electronic fence range, an instruction is sent to the smart terminal and the back-end monitoring center to execute a second prompt, indicating that the person holding the smart terminal has deviated from or mistakenly entered an unauthorized area. The first and second prompts can be any one or more of text, voice, sound and light, and vibration.

[0038] Step 102, Second Verification: When a repair work order or operation task is triggered on the smart terminal, the smart terminal temporarily locks the execution flow of the repair work order or operation task and performs a device identification scan. After identifying the device information, the smart terminal determines whether the device information corresponding to the currently executed repair work order or operation task is consistent with the identified device information. If the device information is consistent, a third prompt is executed to indicate that the device verification is correct, and the repair work order or operation task is unlocked, allowing it to continue execution. If the device information is inconsistent, a fourth prompt is executed to indicate that the device verification is incorrect, and the repair work order or operation task remains locked.

[0039] Step 103: Generate audit logs. The server records personnel movements, verification times, device codes, and operation results throughout the process, forming a security audit log.

[0040] The above methods have already been explained in detail in the description of the methods above, and will not be repeated here.

[0041] This disclosure can be a system, method, and / or computer program product. A computer program product may include a computer-readable storage medium having computer-readable program instructions loaded thereon for causing a processor to implement various aspects of this disclosure.

[0042] Computer-readable storage media can be tangible devices capable of holding and storing instructions for use by an instruction execution device. Computer-readable storage media can be, for example—but not limited to—electrical storage devices, magnetic storage devices, optical storage devices, electromagnetic storage devices, semiconductor storage devices, or any suitable combination of the foregoing. More specific examples (a non-exhaustive list) of computer-readable storage media include: portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), static random access memory (SRAM), portable compact disc read-only memory (CD-ROM), digital multifunction disc (DVD), memory sticks, floppy disks, mechanical encoding devices, such as punch cards or recessed protrusions storing instructions thereon, and any suitable combination of the foregoing. The computer-readable storage media used herein are not to be construed as transient signals themselves, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagating through waveguides or other transmission media (e.g., light pulses through fiber optic cables), or electrical signals transmitted through wires.

[0043] The computer-readable program instructions described herein can be downloaded from computer-readable storage media to various computing / processing devices, or downloaded via a network, such as the Internet, local area network, wide area network, and / or wireless network, to an external computer or external storage device. The network may include copper transmission cables, fiber optic transmission, wireless transmission, routers, firewalls, switches, gateway computers, and / or edge servers. A network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards them to the computer-readable storage media in the respective computing / processing device.

[0044] Computer program instructions used to perform the operations of this disclosure may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, status setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Smalltalk, C++, etc., and conventional procedural programming languages ​​such as the "C" language or similar programming languages. The computer-readable program instructions may execute entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving a remote computer, the remote computer may be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or may be connected to an external computer (e.g., via the Internet using an Internet service provider). In some embodiments, electronic circuitry, such as programmable logic circuitry, field-programmable gate arrays (FPGAs), or programmable logic arrays (PLAs), is personalized by utilizing the status information of the computer-readable program instructions to implement various aspects of this disclosure.

[0045] Various aspects of this disclosure are described herein with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this disclosure. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer-readable program instructions.

[0046] These computer-readable program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus to produce a machine such that, when executed by the processor of the computer or other programmable data processing apparatus, they create means for implementing the functions / actions specified in one or more blocks of the flowchart and / or block diagram. These computer-readable program instructions can also be stored in a computer-readable storage medium that causes a computer, programmable data processing apparatus, and / or other device to operate in a particular manner; thus, the computer-readable medium storing the instructions comprises an article of manufacture that includes instructions for implementing aspects of the functions / actions specified in one or more blocks of the flowchart and / or block diagram.

[0047] Computer-readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other device to cause a series of operational steps to be performed on the computer, other programmable data processing apparatus, or other device to produce a computer-implemented process, thereby causing the instructions executed on the computer, other programmable data processing apparatus, or other device to perform the functions / actions specified in one or more boxes of a flowchart and / or block diagram.

[0048] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the present disclosure. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of an instruction containing one or more executable instructions for implementing a specified logical function. In some alternative implementations, the functions marked in the blocks may occur in a different order than those marked in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, may be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.

[0049] The various embodiments of this disclosure have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or improvement of the technology in the market, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. A nuclear power plant anti-misguided bay and operation verification system, characterized in that, The system includes: a server, multiple sensing and positioning subsystems, multiple smart terminals, and a back-end monitoring center; The server constructs a 3D digital map based on the factory's map or model; for the received maintenance work order or operation task, it delineates a corresponding dynamic electronic fence on the digital map, which corresponds to the physical space range of the equipment associated with the maintenance work order or operation task; the server also sends the received maintenance work order or operation task to the associated smart terminal. Multiple sensing and positioning subsystems are deployed in the operation and maintenance area of ​​a nuclear power plant. Each sensing and positioning subsystem is used to locate smart terminals that appear within a preset range and send the location data of the smart terminal to the smart terminal and the server. The smart terminal has built-in positioning tags, cameras, and communication modules that can communicate with various sensing and positioning subsystems; the smart terminal can obtain device information by scanning the tags on the device through the camera; Based on the maintenance work order or operation task corresponding to each smart terminal, as well as the current location data and the scanned device information, the server determines whether the maintenance personnel holding the smart terminal have gone to the wrong place or made a mistake. When it is determined that the maintenance personnel holding the smart terminal have gone to the wrong place or made a mistake, the server controls the smart terminal and the back-end monitoring center to execute the corresponding prompts.

2. The system according to claim 1, characterized in that, The server records the entire process of the operation and maintenance personnel holding the smart terminal, including their movement trajectory, verification time, device code, and operation results, forming a security audit log.

3. The system according to claim 1, characterized in that, Each smart terminal's interactive interface can intuitively display the electronic fence, the smart terminal's real-time location, the device scanning interface, verification results, and alarm information.

4. The system according to claim 1, characterized in that, The display screen in the back-end monitoring center can provide a global view of the nuclear power plant's operation and maintenance area, and display the location, working status, electronic fence distribution and alarm information of all smart terminals in real time.

5. The system according to claim 1, characterized in that, The sensing and positioning subsystem includes a UWB positioning system and a 5G indoor positioning system, which are deployed in a mixed manner in the nuclear power plant operation and maintenance area.

6. The system according to claim 1, characterized in that, Smart terminals include explosion-proof mobile phones, PDAs, and smart safety helmets.

7. The system according to claim 1, characterized in that, The smart terminal also integrates an OCR engine. When the label is blurry or damaged and the smart terminal cannot recognize it, the smart terminal can call the OCR engine to directly recognize the device code and name on the nameplate.

8. A method for verifying the anti-misoperation bay and operation of a nuclear power plant, the method being implemented based on any one of claims 1 to 7, the method comprising: Step 100, Task Binding and Fence Delineation: The server creates an electronic fence based on the received maintenance work order or operation task, and binds the device code associated with the maintenance work order or operation task within the electronic fence. Step 101, First verification: The server receives location data from smart terminals of various sensing and positioning subsystems in real time and determines whether the location data of each smart terminal is within the associated electronic fence range. If the location data of a smart terminal is within the associated electronic fence range, an instruction is sent to the smart terminal to execute a first prompt, indicating that the person holding the smart terminal has entered the work area. If the location data of a smart terminal exceeds the associated electronic fence range, an instruction is sent to the smart terminal and the back-end monitoring center to execute a second prompt, indicating that the person holding the smart terminal has deviated from or mistakenly entered an unauthorized area. Step 102, Second Verification: When a repair work order or operation task is triggered on the smart terminal, the smart terminal temporarily locks the execution flow of the repair work order or operation task and performs a device identification scan. After identifying the device information, the smart terminal determines whether the device information corresponding to the currently executed repair work order or operation task is consistent with the identified device information. If the device information corresponding to the currently executed repair work order or operation task is consistent with the identified device information, a third prompt is executed to indicate that the device verification is correct and the repair work order or operation task is unlocked, allowing the repair work order or operation task to continue execution. If the device information corresponding to the currently executed repair work order or operation task is inconsistent with the identified device information, a fourth prompt is executed to indicate that the device verification is incorrect and the repair work order or operation task remains locked.

9. The method according to claim 8, characterized in that, The method further includes: Step 103: Generate audit logs. The server records personnel movements, verification times, device codes, and operation results throughout the process, forming a security audit log.

10. A non-volatile computer-readable storage medium storing computer program instructions thereon, characterized in that, When the computer program instructions are executed by the processor, they implement the method of claim 8 or 9.

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