Express stack determination method and device, electronic equipment and storage medium

Abstract

The invention discloses an express stack determination method and device, electronic equipment and a storage medium. The method comprises the following steps: determining a first image, wherein the first image is an image obtained by shooting an express parcel from the upper part of the express parcel; the first image at least comprises one express; if the height difference exists between the first express and the first surface, it is determined that an express stack exists; the first express is the uppermost express in the first image, and the first surface is the surface bearing the lowermost express in the expresses in the first image. According to the technical scheme, the first image is determined, if the height difference exists between the first express item and the first surface, it is determined that the express item stack exists, whether the express item stack exists or not can be judged quickly and accurately, and therefore original manual checking is converted into automatic determination, the judgment efficiency is improved, and the cost is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of express sorting technology, and in particular to an express stacking piece determination method and device, an electronic device, and a storage medium. BACKGROUND

[0002] With the continuous increase in the transaction volume of e-commerce platforms, the express transportation volume also increases, and the workload of express sorting gradually increases.

[0003] In the express sorting process, it is easy to have multiple express on the same trolley, but due to the overlap between express and express, errors occur in express sorting. The current small piece cross belt uses a gray scale instrument to determine whether there are two or more packages in a single trolley of the small piece cross belt, but the gray scale instrument can only collect black and white package pictures, and the main function is to determine the position of the package in the trolley, and it is not accurate to determine multiple pieces in a trolley. SUMMARY

[0004] The present application provides an express stacking piece determination method and device, an electronic device, and a storage medium to solve the problem of difficulty in determining whether the express is stacked in the express sorting process.

[0005] According to one aspect of the present application, the method comprises:

[0006] determining a first image, the first image being an image taken from above the express; and the first image including at least one express;

[0007] if there is a height difference between the first express and the first surface, it is determined that there is express stacking; the first express is the uppermost express in the first image, and the first surface is the surface on which the lowermost express in the first image is carried.

[0008] According to another aspect of the present application, an express stacking piece determination device is provided, which comprises:

[0009] a first image determination module for determining a first image, the first image being an image taken from above the express; and the first image including at least one express;

[0010] an express stacking piece determination module for determining that there is express stacking if there is a height difference between the first express and the first surface; the first express is the uppermost express in the first image, and the first surface is the surface on which the lowermost express in the first image is carried.

[0011] According to another aspect of the present application, an electronic device is provided, which comprises:

[0012] at least one processor; and

[0013] a memory communicatively connected to the at least one processor; wherein

[0014] The memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor to enable the at least one processor to perform the parcel stack determination method of any of the embodiments of the present application.

[0015] According to another aspect of the present application, a computer readable storage medium is provided, which stores computer instructions for enabling a processor to implement the parcel stack determination method of any of the embodiments of the present application when executed by the processor.

[0016] The technical solution of the embodiments of the present application can determine the first image, and if there is a height difference between the first parcel and the first surface, it is determined that there is a parcel stack, which can quickly and accurately determine whether there is a parcel stack, thereby converting the original manual checking into automatic determination, improving the determination efficiency and reducing the cost.

[0017] It should be understood that the content described in this part is not intended to identify the key or important features of the embodiments of the present application, nor to limit the scope of the present application. Other features of the present application will become apparent from the following description. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed in the embodiment description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0019] Figure 1 is a flow chart of a parcel stack determination method according to the first embodiment of the present application;

[0020] Figure 2 is a flow chart of another parcel stack determination method according to the second embodiment of the present application;

[0021] Figure 3 is a structural schematic diagram of a parcel stack determination device according to the third embodiment of the present application;

[0022] Figure 4 is a structural schematic diagram of an electronic device for implementing the parcel stack determination method of the embodiments of the present application. DETAILED DESCRIPTION

[0023] In the following, the technical solutions in the embodiments of the present application will be described clearly and completely in conjunction with the drawings in the embodiments of the present application, so that those skilled in the art can better understand the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work should fall within the scope of the present application.

[0024] It should be noted that the terms "first", "second" and the like in the description and claims of the present application and the above drawings are used to distinguish similar objects, and do not necessarily indicate a specific order or sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units does not necessarily have to include only those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0025] Embodiment one

[0026] Figure 1 A flowchart of a method for determining express stacking is provided for the first embodiment of the present application. The present embodiment can be applied to determine whether there is express stacking in the express sorting process. The method can be executed by an express stacking determination device, which can be realized in the form of hardware and / or software, and can be configured in an electronic device with data processing capability. As shown in the figure, the method comprises: Figure 1

[0027] S110, determine a first image, the first image being an image taken from above the express; the first image comprising at least one express.

[0028] The generation of the first image can be real-time shooting or obtaining from a pre-taken image gallery. The first image can be taken from directly above the express or from an oblique angle. The at least one express in the first image means that when the express is taken, there can be only one express, in which case the first image taken only contains one express, but in the actual shooting process, all the expresses should be taken as much as possible.

[0029] S120, if there is a height difference between the first express and the first surface, it is determined that there is express stacking; the first express being the uppermost express in the first image, and the first surface being the surface bearing the lowermost express among the expresses in the first image. ​

[0030] The height difference can be a height difference between the first express delivery and the first surface. The first express delivery can be an express delivery with the highest height from the first surface among the express deliveries.

[0031] Based on the first image, the height difference between the first express delivery and the first surface is determined. If the height difference is zero, it is determined that the first express delivery is adjacent to the first surface, and it is determined that there is no other express delivery under the first express delivery, and it is determined that there is no express delivery stack.

[0032] If the height difference is not zero, it is determined that there is a gap between the first express delivery and the first surface, and it is determined that there is another express delivery between the first express delivery and the first surface, and it is determined that there is an express delivery stack.

[0033] By determining the first image, if there is a height difference between the first express delivery and the first surface, it is determined that there is an express delivery stack, which can quickly and accurately determine whether there is an express delivery stack, thereby changing the original manual check to automatic determination, improving the determination efficiency and reducing the cost.

[0034] In an optional solution, the height difference between the first express delivery and the first surface is determined, comprising:

[0035] Based on the pre-trained depth recognition model, the first image is recognized to determine the height difference between the first express delivery and the first surface.

[0036] The depth recognition model is a model for determining the height difference between an article and a plane. The depth recognition model can be various existing models, which are not limited in the present application.

[0037] Based on the pre-trained depth recognition model, the first image is analyzed to determine the height difference between the first express delivery and the first surface.

[0038] By using the depth recognition model, the height difference between the first express delivery and the first surface is determined by recognizing the first image, which can quickly determine the height difference, thereby providing a basis for subsequent express delivery sorting during the sorting of the first express delivery.

[0039] In an optional solution, the training process of the depth recognition model comprises:

[0040] The express delivery stack sample image is determined, and the express delivery stack sample image includes at least a first type of sample image, a second type of sample image and a third type of sample image; the first type of sample image is a sample image in which multiple express deliveries are overlapped; the second type of sample image is a sample image in which multiple express deliveries are partially overlapped; and the third type of sample image is a sample image in which multiple express deliveries are completely overlapped.

[0041] The depth recognition model is trained based on the express stacking sample image.

[0042] To ensure the accurate recognition of the depth recognition model on the height difference in the first image, the application constructs samples for different situations of express stacking, and respectively trains the depth recognition model based on the samples in different situations, thereby improving the recognition accuracy and efficiency of the depth recognition model.

[0043] Since the purpose of judging express stacking in the express industry is mainly express sorting, to avoid the allocation of express with occlusion to the wrong area due to express overlapping. Therefore, there are multiple express but no overlapping, this kind of situation can be regarded as express stacking in the express sorting process. In addition, it also includes the phenomenon of partial overlapping between multiple express and complete overlapping between multiple express.

[0044] For different situations, express stacking sample images including first, second and third sample images are constructed, and the depth recognition model is trained based on the express stacking sample images, to ensure that the depth recognition model can accurately recognize the three situations.

[0045] In the actual working process of the depth recognition model, if multiple express can be directly determined, the identification of the height difference can be abandoned, thereby reducing the consumption of computing resources of the depth recognition model and improving the judgment efficiency of the depth recognition model.

[0046] Taking unmanned vehicle express transportation as a sorting scene as an example, after the unmanned vehicle receives the goods and moves to the storage cabinet, the unmanned vehicle will place the stored express in the storage cabinet to realize express sorting. However, when the unmanned vehicle places the express, the situation of express stacking may occur, at this time the unmanned vehicle may place multiple express in the same storage cabinet at the same time, thereby causing express storage error, and even loss problem.

[0047] Accordingly, when the unmanned vehicle places the express, the express can be photographed to obtain a first image, and the height difference between the uppermost express and the surface of the storage cabinet is analyzed according to the first image. When there is a height difference, it can be determined that there are other express under the first express.

[0048] Taking a pipeline sorting scene as an example, one express trolley represents one conveying unit in the conveying belt, and each conveying unit should only be responsible for conveying one express. At this time, if multiple express are contained in the express trolley, it is easy to sort multiple express into the same sorting area, thereby causing express distribution error, and even loss.

[0049] At this time, the package can be photographed during the delivery process of the delivery vehicle to obtain the first image. Based on the first image, the height difference between the top package and the surface of the delivery vehicle can be analyzed. If there is a height difference, it can be determined that there are other packages below the first package.

[0050] By adopting the technical solution of this application, if there is a height difference between the first express delivery and the first surface, it is determined that there are stacked express delivery packages by determining the first image. This enables a quick and accurate judgment on whether there are stacked express delivery packages, thereby transforming the original manual inspection into automatic determination, improving judgment efficiency and reducing costs.

[0051] Example 2

[0052] Figure 2 This invention provides a flowchart of another method for determining stacked express parcels. This embodiment further optimizes the process of determining the first image in the aforementioned embodiments, based on the above embodiments. This embodiment can be combined with various optional solutions in one or more of the above embodiments. Figure 2 As shown, the method for determining stacked express parcels in this embodiment may include the following steps:

[0053] S210, using a depth-of-field camera, captures images of the express delivery unit to obtain the first image.

[0054] The depth-of-field camera is installed between the scanning camera and the grayscale meter in the small cross-belt loop.

[0055] A depth camera is an imaging device that can directly acquire three-dimensional spatial position information of objects in a scene. A small parcel cross-belt loop is an automated sorting system designed for small parcels in the logistics sorting field. A parcel transport unit can be the smallest unit for transporting parcels during the parcel sorting process. It can be a small cart, an unmanned vehicle, etc.

[0056] To avoid excessive costs due to large-scale modifications to the small cross-belt loops during practical use, a depth-of-field camera can be mounted between the scanning camera and the grayscale meter within the small cross-belt loops. Besides this position, other flexible adjustments can be made according to actual circumstances, and this application does not impose any restrictions on this.

[0057] S220. Determine whether there is any partial overlap between the various express packages in the first image.

[0058] S230. If it exists, then it is determined that there are stacked express packages, but the height difference between the first express package and the first surface is not determined.

[0059] To reduce the computational burden on the depth recognition model, the first image can be analyzed first to determine whether there is overlap in the first image. If it is directly determined that there is partial overlap, then the height difference between the first express and the first surface does not need to be determined.

[0060] Optionally, the first image can be analyzed to determine the number of express packages in the first image. If the number of express packages is greater than two, the height difference between the first express package and the first surface does not need to be determined.

[0061] S240. If there is a height difference between the first express delivery and the first surface, it is determined that there are stacked express delivery packages; the first express delivery is the express delivery at the top of all express delivery packages in the first image, and the first surface is the surface in the first image that carries the express delivery package at the bottom.

[0062] The technical solution of this application uses a depth-sensing camera to capture images of the express delivery unit to obtain a first image; it determines whether there is partial overlap between the express packages in the first image; if so, it determines that there are stacked express packages, without determining the height difference between the first express package and the first surface. Thus, through simple image recognition, it can be directly determined whether the first image contains multiple express packages, and if multiple express packages are contained, the height difference between the first express package and the first surface is not determined, thereby reducing the computational pressure on the depth recognition model.

[0063] Example 3

[0064] Figure 3 This invention provides a structural block diagram of a package stacking determination device, applicable to situations where packages are stacked during package sorting. This package stacking determination device can be implemented in hardware and / or software and can be configured in an electronic device with data processing capabilities. Figure 3 As shown, the express parcel stacking determination device of this embodiment may include: a first image determination module 310 and an express parcel stacking judgment module 320. Wherein:

[0065] The first image determination module 310 is used to determine a first image, which is an image of the express delivery taken from above; the first image includes at least one express delivery.

[0066] The express delivery stacking judgment module 320 is used to determine that there are stacked express delivery packages if there is a height difference between the first express delivery package and the first surface; the first express delivery package is the express delivery package at the top of all express delivery packages in the first image, and the first surface is the surface in the first image that carries the express delivery package at the bottom.

[0067] Based on the above embodiments, optionally, the express delivery stacking judgment module includes:

[0068] Based on a pre-trained deep recognition model, the first image is identified to determine the height difference between the first express delivery and the first surface.

[0069] Based on the above embodiments, optionally, the training process of the deep recognition model includes:

[0070] The sample images of stacked express parcels are determined. The sample images of stacked express parcels include at least a first type of sample image, a second type of sample image, and a third type of sample image. The first type of sample image is a sample image in which there are multiple express parcels but the express parcels do not overlap. The second type of sample image is a sample image in which there are multiple express parcels and the express parcels partially overlap. The third type of sample image is a sample image in which there are multiple express parcels and the express parcels completely overlap.

[0071] A deep recognition model is trained based on sample images of stacked express parcels.

[0072] Based on the above embodiments, optionally, before the express delivery stacking judgment module 320, the following further includes:

[0073] Determine whether there is any partial overlap between the various express delivery packages in the first image;

[0074] If it exists, then it is determined that there are stacked express packages, but the height difference between the first express package and the first surface is not determined.

[0075] Optionally, based on the above embodiments, after the express delivery stacking judgment module 320, the following further includes:

[0076] The unique code of the express delivery unit corresponding to the first image is determined. The express delivery unit is used to transport and sort express packages. The first surface is the surface that comes into contact with the express package when the express delivery unit transports the express package.

[0077] Based on the unique code, the express delivery unit is moved to the express sorting anomaly area.

[0078] Based on the above embodiments, optionally, the first image determination module 310 includes:

[0079] The first image is obtained by taking a picture of the express delivery unit using a depth-of-field camera.

[0080] The depth-of-field camera is installed between the scanning camera and the grayscale meter in the small cross-belt loop.

[0081] The express delivery stacking determination device provided in the embodiments of the present invention can execute the express delivery stacking determination method provided in any embodiment of the present invention, and has the corresponding functional modules and beneficial effects of the method execution.

[0082] Example 4

[0083] Figure 4A schematic diagram of an electronic device 10, which can be used to implement embodiments of the present invention, is shown. The electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device can also represent various forms of mobile devices, such as personal digital processors, cellular phones, smartphones, wearable devices (e.g., helmets, glasses, watches, etc.), and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely illustrative and are not intended to limit the implementation of the invention described and / or claimed herein.

[0084] like Figure 4 As shown, the electronic device 10 includes at least one processor 11 and a memory, such as a read-only memory (ROM) 12 or a random access memory (RAM) 13, communicatively connected to the at least one processor 11. The memory stores computer programs executable by the at least one processor. The processor 11 can perform various appropriate actions and processes based on the computer program stored in the ROM 12 or loaded into the RAM 13 from storage unit 18. The RAM 13 can also store various programs and data required for the operation of the electronic device 10. The processor 11, ROM 12, and RAM 13 are interconnected via a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0085] Multiple components in electronic device 10 are connected to I / O interface 15, including: input unit 16, such as keyboard, mouse, etc.; output unit 17, such as various types of displays, speakers, etc.; storage unit 18, such as disk, optical disk, etc.; and communication unit 19, such as network card, modem, wireless transceiver, etc. Communication unit 19 allows electronic device 10 to exchange information / data with other devices through computer networks such as the Internet and / or various telecommunications networks.

[0086] Processor 11 can be a variety of general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special-purpose artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any suitable processor, controller, microcontroller, etc. Processor 11 performs the various methods and processes described above, such as the express delivery stacking determination method.

[0087] In some embodiments, the express parcel stacking determination method may be implemented as a computer program tangibly contained in a computer-readable storage medium, such as storage unit 18. In some embodiments, part or all of the computer program may be loaded and / or installed on electronic device 10 via ROM 12 and / or communication unit 19. When the computer program is loaded into RAM 13 and executed by processor 11, one or more steps of the express parcel stacking determination method described above may be performed. Alternatively, in other embodiments, processor 11 may be configured to perform the express parcel stacking determination method by any other suitable means (e.g., by means of firmware).

[0088] Various embodiments of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), systems-on-a-chip (SoCs), payload-programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments may include implementations in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which may be a dedicated or general-purpose programmable processor, capable of receiving data and instructions from a storage system, at least one input device, and at least one output device, and transmitting data and instructions to the storage system, the at least one input device, and the at least one output device.

[0089] Computer programs used to implement the methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when executed by the processor, the computer programs cause the functions / operations specified in the flowcharts and / or block diagrams to be performed. The computer programs may be executed entirely on a machine, partially on a machine, or as a standalone software package, partially on a machine and partially on a remote machine, or entirely on a remote machine or server.

[0090] In the context of this invention, a computer-readable storage medium can be a tangible medium that may contain or store a computer program for use by or in conjunction with an instruction execution system, apparatus, or device. A computer-readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination thereof. Alternatively, a computer-readable storage medium may be a machine-readable signal medium. More specific examples of machine-readable storage media include electrical connections based on one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0091] To provide interaction with a user, the systems and techniques described herein can be implemented on an electronic device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and pointing device (e.g., a mouse or trackball) through which the user provides input to the electronic device. Other types of devices can also be used to provide interaction with the user; for example, feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including sound input, voice input, or tactile input).

[0092] The systems and technologies described herein can be implemented in computing systems that include backend components (e.g., as data servers), or middleware components (e.g., application servers), or frontend components (e.g., user computers with graphical user interfaces or web browsers through which users can interact with implementations of the systems and technologies described herein), or any combination of such backend, middleware, or frontend components. The components of the system can be interconnected via digital data communication of any form or medium (e.g., communication networks). Examples of communication networks include local area networks (LANs), wide area networks (WANs), blockchain networks, and the Internet.

[0093] A computing system can include clients and servers. Clients and servers are generally located far apart and typically interact through communication networks. The client-server relationship is created by computer programs running on the respective computers and having a client-server relationship with each other. The server can be a cloud server, also known as a cloud computing server or cloud host, which is a hosting product within the cloud computing service system to address the shortcomings of traditional physical hosts and VPS services, such as high management difficulty and weak business scalability.

[0094] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0095] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A method for determining stacked express parcels, characterized in that, include: The first image is determined as an image taken from above the express delivery package; The first image includes at least one express delivery; If there is a height difference between the first express package and the first surface, then it is determined that there are stacked express packages. The first package is the package at the top of all packages in the first image, and the first surface is the surface in the first image that carries the package at the bottom.

2. The method according to claim 1, characterized in that, Determining the height difference between the first express delivery and the first surface includes: Based on a pre-trained depth recognition algorithm, the first image is identified to determine the height difference between the first express delivery and the first surface.

3. The method according to claim 2, characterized in that, The training process of the deep recognition algorithm includes: The method involves determining sample images of stacked express parcels, which include at least a first type of sample image, a second type of sample image, and a third type of sample image. The first type of sample image is one where multiple parcels exist but do not overlap. The second type of sample image is one where multiple parcels exist and partially overlap. The third type of sample image is one where multiple parcels exist and completely overlap. The deep recognition algorithm is trained based on sample images of stacked express parcels.

4. The method according to claim 2, characterized in that, Before identifying the first image based on a pre-trained depth recognition algorithm and determining the height difference between the first express delivery and the first surface, the method further includes: Determine whether there is any partial overlap among the various express delivery packages in the first image; If it exists, then it is determined that there are stacked express packages, but the height difference between the first express package and the first surface is not determined.

5. The method according to claim 1, characterized in that, After confirming the existence of stacked packages, the following is also included: The unique code of the express delivery unit corresponding to the first image is determined. The express delivery unit is used to transport and sort express packages. The first surface is the surface that comes into contact with the express package when the express delivery unit transports the express package. Based on the unique code, the express delivery unit is moved to the express sorting anomaly area.

6. The method according to claim 5, characterized in that, Determine the first image, including: A first image is obtained by taking a picture of the express delivery unit using a depth-of-field camera. The depth-of-field camera is installed between the scanning camera and the grayscale meter in the small cross-belt loop.

7. A device for determining the stacking of express parcels, characterized in that, include: The first image determination module is used to determine a first image, which is an image of the express delivery taken from above. The first image includes at least one express delivery; The express delivery stacking judgment module is used to determine that there are stacked express delivery packages if there is a height difference between the first express delivery package and the first surface. The first package is the package at the top of all packages in the first image, and the first surface is the surface in the first image that carries the package at the bottom.

8. The apparatus according to claim 7, characterized in that, The express delivery stacking judgment module includes: The express delivery stacking determination module is used to identify the first image based on a pre-trained depth recognition algorithm and determine the height difference between the first express delivery and the first surface.

9. An electronic device, characterized in that, The electronic device includes: At least one processor; and A memory communicatively connected to the at least one processor; wherein, The memory stores a computer program that can be executed by the at least one processor, the computer program being executed by the at least one processor to enable the at least one processor to perform the express delivery stacking determination method according to any one of claims 1-6.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions that cause a processor to execute the express delivery stacking determination method according to any one of claims 1-6.

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