Blood glucose monitoring method, device, continuous glucose monitoring apparatus, and storage medium

Abstract

The present disclosure relates to a blood glucose monitoring method, device, continuous blood glucose monitoring apparatus and storage medium, the apparatus comprising: a control unit, a constant current source circuit, a switching switch, an AFE unit, an electrochemical sensor, a sampling resistor, wherein the electrochemical sensor comprises a draw electrode, a first end of the constant current source circuit is connected with the control unit, a second end of the constant current source circuit is connected with a first end of the switching switch, a second end of the switching switch is connected with a first end of the sampling resistor, a second end of the sampling resistor is connected with the control unit, a third end of the switching switch is connected with the draw electrode, a fourth end of the switching switch is connected with the control unit, a first end of the AFE unit is connected with the control unit, a second end of the AFE unit is connected with the electrochemical sensor, and the second end of the sampling resistor is also connected with the electrochemical sensor.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to blood glucose monitoring technology, and more particularly, to a blood glucose monitoring method and device, a continuous blood glucose monitoring apparatus, and a storage medium. BACKGROUND

[0002] A continuous blood glucose monitoring (CGM) apparatus is a key technology for indirectly reflecting blood glucose level by detecting glucose concentration in tissue fluid. The working principle of the CGM apparatus is as follows: glucose in extracted tissue fluid undergoes electrochemical reaction under the action of an active enzyme of a sensor, and generates a weak reaction current (usually in the order of nano-ampere to micro-ampere) that is proportional to the glucose concentration. The reaction current flows through a sampling resistor, and the voltage across the sampling resistor is collected to calculate the reaction current value, and finally the blood glucose concentration is converted.

[0003] A significant defect exists in the prior art: the calculation accuracy of blood glucose concentration directly depends on the absolute accuracy of the sampling resistor. Generally, in order to ensure the calculation accuracy of blood glucose concentration, a low-temperature-drift high-precision sampling resistor with an accuracy of ±0.1% or even higher must be selected, which significantly increases the hardware cost of the system. Even if such a high-cost resistor is used, the resistance value of the resistor will still drift slightly under the influence of temperature change, long-term aging, and the like, thereby introducing measurement errors that are difficult to compensate for, and ultimately affecting the accuracy and reliability of blood glucose detection. SUMMARY

[0004] An object of the present application is to provide a new technical solution for a continuous blood glucose monitoring apparatus.

[0005] According to a first aspect of the present application, a continuous blood glucose monitoring apparatus is provided, comprising: a control unit, a constant current source circuit, a switching switch, an AFE unit, an electrochemical sensor, and a sampling resistor, wherein the electrochemical sensor comprises an extraction electrode,

[0006] The first end of the constant current source circuit is connected to the control unit, the second end of the constant current source circuit is connected to the first end of the switching switch, the second end of the switching switch is connected to the first end of the sampling resistor, the second end of the sampling resistor is connected to the control unit, the third end of the switching switch is connected to the extraction electrode, and the fourth end of the switching switch is connected to the control unit.

[0007] The first end of the AFE unit is connected to the control unit, the second end of the AFE unit is connected to the electrochemical sensor, and the second end of the sampling resistor is also connected to the electrochemical sensor.

[0008] Optionally, the switching switch comprises a first channel and a second channel, wherein,

[0009] The constant current source circuit is connected with the sampling resistor through the first channel, and the constant current source circuit is connected with the extraction electrode through the second channel.

[0010] Optionally, a control switch is arranged between the control unit and the constant current source circuit.

[0011] According to a second aspect of the present application, a blood glucose monitoring method is provided, which is applied to the continuous blood glucose monitoring device according to any one of the first aspect, and the method comprises:

[0012] controlling the constant current source circuit to output a first current, so that the first current flows through the sampling resistor, and obtaining a voltage across the sampling resistor, denoted as a first voltage;

[0013] controlling the constant current source circuit to provide a loading voltage for the extraction electrode, so that the extraction electrode extracts the user's tissue fluid based on the loading voltage;

[0014] in the case that the user's tissue fluid enters the electrochemical sensor, so that the electrochemical sensor generates a second current through an electrochemical reaction, and the second current flows through the sampling resistor, obtaining a voltage across the sampling resistor, denoted as a second voltage;

[0015] determining the second current according to the first voltage, the first current and the second voltage;

[0016] determining a blood glucose concentration value of the corresponding user according to the second current.

[0017] Optionally, a switching switch is arranged between the constant current source circuit and the sampling resistor, and before the control of the constant current source circuit to output the first current so that the first current flows through the sampling resistor, the method further comprises:

[0018] controlling the switching switch to be connected with the first channel, so that the constant current source circuit is connected with the sampling resistor;

[0019] The control of the constant current source circuit to provide a loading voltage for the extraction electrode, so that the extraction electrode extracts the user's tissue fluid based on the loading voltage, comprises:

[0020] controlling the switching switch to be connected with the second channel, so that the constant current source circuit is connected with the extraction electrode.

[0021] Optionally, an IO1 pin of the control unit of the continuous blood glucose monitoring device is connected with the constant current source circuit, and the control of the constant current source circuit to output the first current comprises:

[0022] controlling the IO1 pin to output a high level, so that the constant current source circuit outputs the first current.

[0023] Optionally, an IO2 pin of the control unit of the continuous blood glucose monitoring device is connected with a CTRL pin of the switch, wherein the control switch is connected with the first channel, and the control switch is connected with the second channel, comprising:

[0024] controlling the CTRL pin to output a high level to make the switch connected with the first channel, and controlling the CTRL pin to output a low level to make the switch connected with the second channel.

[0025] Optionally, the blood glucose concentration value of the corresponding user is determined according to the second current, comprising:

[0026] obtaining a corresponding relationship between the current and the blood glucose concentration value;

[0027] determining the blood glucose concentration value of the corresponding user according to the second current and the corresponding relationship between the current and the blood glucose concentration value.

[0028] According to a third aspect of the present application, a blood glucose monitoring device is provided, comprising a memory and a processor, the memory stores a computer program, the computer program is used to control the processor to operate to execute the method according to any one of the second aspect.

[0029] According to a fourth aspect of the present application, a computer readable storage medium is provided, which stores computer program instructions, the computer program instructions are executed by a processor to realize the method according to any one of the second aspect.

[0030] The continuous blood glucose monitoring device provided by the present disclosure comprises a control unit, a constant current source circuit, a switch, an AFE unit, an electrochemical sensor and a sampling resistor. The electrochemical sensor comprises an extraction electrode. The first end of the constant current source circuit is connected with the control unit. The second end of the constant current source circuit is connected with the first end of the switch. The second end of the switch is connected with the first end of the sampling resistor. The second end of the sampling resistor is connected with the control unit. The third end of the switch is connected with the extraction electrode. The fourth end of the switch is connected with the control unit. The first end of the AFE unit is connected with the control unit. The second end of the AFE unit is connected with the electrochemical sensor. The second end of the sampling resistor is also connected with the electrochemical sensor. The influence of the absolute accuracy and the drift of the sampling resistor on the accuracy of the non-invasive CGM blood glucose detection is fundamentally eliminated, so that high-precision and high-stability blood glucose measurement is realized without using high-cost and high-precision sampling resistors.

[0031] The features and advantages of embodiments of the present application will become apparent from the following detailed description of exemplary embodiments thereof, taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0032] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the present specification and, together with the description, serve to explain the principles of embodiments of the present specification.

[0033] Figure 1 is a schematic diagram of a continuous glucose monitoring device according to one embodiment of the present application.

[0034] Figure 2 is a schematic diagram of a continuous glucose monitoring device according to another embodiment of the present application.

[0035] Figure 3 is a schematic diagram of a continuous glucose monitoring method according to one embodiment of the present application.

[0036] Figure 4 is a schematic diagram of a continuous glucose monitoring method according to another embodiment of the present application.

[0037] Figure 5 is a schematic diagram of a continuous glucose monitoring device according to one embodiment of the present application. DETAILED DESCRIPTION

[0038] Various exemplary embodiments of the present specification will now be described in detail with reference to the accompanying drawings. If it is considered that specific detailed description of known functions or configurations makes the

[0039] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way limiting to the scope of the embodiments of the present specification and their applications or uses.

[0040] It should be noted that like numbers and letters refer to like items throughout the drawings, and once an item is defined in one drawing, it is not necessary to discuss it further in subsequent drawings.

[0041] To solve the above technical problems, the present disclosure provides a continuous glucose monitoring device, comprising a control unit, a constant current source circuit, a switching switch, an AFE unit, an electrochemical sensor, a sampling resistor, the electrochemical sensor comprising a draw electrode, a first end of the constant current source circuit being connected with the control unit, a second end of the constant current source circuit being connected with a first end of the switching switch, a second end of the switching switch being connected with a first end of the sampling resistor, a second end of the sampling resistor being connected with the control unit, a third end of the switching switch being connected with the draw electrode, a fourth end of the switching switch being connected with the control unit, a first end of the AFE unit being connected with the control unit, a second end of the AFE unit being connected with the electrochemical sensor, and the second end of the sampling resistor also being connected with the electrochemical sensor, which fundamentally eliminates the influence of the absolute accuracy and drift of the sampling resistor on the accuracy of the non-invasive CGM glucose detection, thereby realizing high-precision and high-stability glucose measurement without using high-cost and high-precision sampling resistors.

[0042] An embodiment of the present application provides a continuous blood glucose monitoring device. According to Figure 1 As shown in the figure, the continuous blood glucose monitoring device comprises a control unit, a constant current source circuit, a switching switch, an AFE (Active Front End) unit, an electrochemical sensor and a sampling resistor, wherein the electrochemical sensor comprises an extraction electrode.

[0043] The control unit can be a microprocessor (MCU), which is an operation control unit of the continuous blood glucose monitoring device.

[0044] The constant current source circuit is used to generate a fixed current value, which can act on the skin of a user to generate an electric field for extracting tissue fluid. In addition, the fixed current generated by the constant current source circuit passes through the sampling resistor, and the voltage across the sampling resistor is collected to take the voltage and the fixed current value as related parameters for determining the current value generated by the electrochemical sensor due to an electrochemical reaction.

[0045] The AFE unit is used to provide a voltage for normal operation of the electrochemical sensor.

[0046] The AFE unit and the electrochemical sensor both have a three-electrode structure, namely a working electrode, a reference electrode and an auxiliary electrode. The AFE unit and the electrochemical sensor are connected through the three-electrode structure.

[0047] The glucose in the tissue fluid extracted by the extraction electrode can have an electrochemical reaction with the reaction enzyme in the electrochemical sensor. The current generated by the electrochemical reaction of the electrochemical sensor flows through the sampling resistor.

[0048] As shown in the figure, Figure 1 The first end of the constant current source circuit is connected with the control unit, that is, the IO1 pin of the control unit is connected with the VDD pin of the constant current source circuit. The second end of the constant current source circuit is connected with the first end of the switching switch, that is, the constant current source circuit is also connected with the COM pin of the switching switch. The second end of the switching switch is connected with the first end of the sampling resistor, that is, the A pin of the switching switch is connected with the sampling resistor. The second end of the sampling resistor is connected with the control unit. The third end of the switching switch is connected with the extraction electrode, that is, the B pin of the switching switch is connected with the extraction electrode. The fourth end of the switching switch is connected with the control unit, that is, the IO2 pin of the control unit is connected with the CTRL pin of the switching switch.

[0049] As shown in the figure, Figure 1 The first end of the AFE unit is connected with the control unit, the second end of the AFE unit is connected with the electrochemical sensor, and the second end of the sampling resistor is also connected with the electrochemical sensor.

[0050] The switching switch comprises a first channel and a second channel. As shown in the figure, Figure 1As shown, the first channel corresponds to the COM-A conduction, and the second channel corresponds to the COM-B conduction. The constant current source circuit is connected to the sampling resistor through the first channel, and the constant current source circuit is connected to the extraction electrode through the second channel.

[0051] In some embodiments, according to Figure 2 As shown, a control switch is provided between the control unit and the constant current source circuit.

[0052] When the constant current source circuit needs to output its first current, the control switch is closed; when the constant current source circuit does not need to output its first current, the control switch is opened. This achieves safe and precise power management of the constant current source circuit, saving unnecessary energy consumption.

[0053] One embodiment of the present invention provides a blood glucose monitoring method. This method is applied to a continuous glucose monitoring device.

[0054] according to Figure 3 As shown, the blood glucose monitoring method in this embodiment includes the following steps S310 to S350.

[0055] Step S310: Control the constant current source circuit to output a first current so that the first current flows through the sampling resistor and obtain the voltage across the sampling resistor, which is recorded as the first voltage.

[0056] A switching switch is provided between the constant current source circuit and the sampling resistor. Before step S310, the method further includes: controlling the switching switch to connect the first channel so that the constant current source circuit is connected to the sampling resistor.

[0057] like Figure 1 As shown, the IO2 pin of the control unit is connected to the CTRL pin of the toggle switch. Controlling the toggle switch to connect to the first channel specifically involves controlling the CTRL pin to output a high level, thereby connecting the toggle switch to the first channel. That is, enabling the channel between COM and A.

[0058] After the first channel is turned on, the constant current source circuit is controlled to output the first current so that the first current flows through the sampling resistor.

[0059] like Figure 1 As shown, the IO1 pin of the control unit is connected to the constant current source circuit. Controlling the constant current source circuit to output the first current specifically includes controlling the IO1 pin to output a high level, so that the constant current source circuit outputs the first current.

[0060] The first current Iref is a fixed current value and is a known quantity.

[0061] When the first current Iref flows through the sampling resistor, the voltage across the sampling resistor obtained by the control unit is the first voltage, denoted as Vref. According to Ohm's law, Vref = Iref × R, where R is the resistance of the sampling resistor.

[0062] Step S320: Control the constant current source circuit to provide a loading voltage to the extraction electrode so that the extraction electrode can extract the user's tissue fluid based on the loading voltage.

[0063] Specifically, the control switch connects to the second channel so that the constant current source circuit is connected to the extraction electrode.

[0064] like Figure 1 As shown, the IO2 pin of the control unit is connected to the CTRL pin of the toggle switch. Controlling the toggle switch to connect to the second channel specifically involves controlling the CTRL pin to output a low level, thereby connecting the toggle switch to the second channel. That is, enabling the channel between COM and B.

[0065] In some embodiments, the CTRL pin is controlled to output a low level to connect the toggle switch to the first channel, and the CTRL pin is controlled to output a high level to connect the toggle switch to the second channel. This is determined by the toggle switch itself.

[0066] In step S330, when the user's tissue fluid enters the electrochemical sensor, causing the electrochemical sensor to undergo an electrochemical reaction and generate a second current, and the second current flows through the sampling resistor, the voltage across the sampling resistor is obtained and recorded as the second voltage.

[0067] When the second current I flows through the sampling resistor, the voltage across the sampling resistor obtained by the control unit is the second voltage, denoted as V. According to Ohm's law, V = I×R, where R is the resistance of the sampling resistor.

[0068] Step S340: Determine the second current based on the first voltage, the first current, and the second voltage.

[0069] The second current is calculated using the following formula.

[0070]

[0071] The derivation of this formula is as follows: From Vref = Iref×R, we can calculate R = Vref / Iref. Substituting R into V = I×R, we get V = I×(Vref / Iref), thus deriving I = (V / Vref) ×Iref. The key to this formula is that the resistance value R of the sampling resistor is completely eliminated during the calculation process.

[0072] Step S350: Determine the blood glucose concentration value of the corresponding user based on the second current.

[0073] In some embodiments, the step S350 specifically comprises: obtaining a correspondence between the current and the blood glucose concentration value; and determining the blood glucose concentration value of the corresponding user according to the second current, the correspondence between the current and the blood glucose concentration value.

[0074] The correspondence between the current and the blood glucose concentration value is pre-stored information and can be directly obtained. The correspondence between the current and the blood glucose concentration value can be a mapping table, or a calculation formula of the current and the blood glucose concentration value.

[0075] In combination with Figure 2 , the blood glucose monitoring method provided by the present application is described below with a specific embodiment.

[0076] According to Figure 4 , the blood glucose monitoring method comprises steps S401-S409.

[0077] In step S401, the CTRL pin is controlled to output a high level, so as to make the switching switch connect the first channel.

[0078] In step S402, the IO1 pin is controlled to output a high level, so as to make the constant current source circuit output a first current.

[0079] In step S403, the voltage across the sampling resistor is obtained when the first current Iref flows through the sampling resistor, and is recorded as a first voltage Vref.

[0080] In step S404, the CTRL pin is controlled to output a low level, so as to make the switching switch connect the second channel, and further provide a loading voltage for the extraction electrode, so as to make the extraction electrode extract the user's tissue fluid based on the loading voltage.

[0081] In step S405, the IO1 pin is controlled to output a low level, so as to make the constant current source circuit no longer output the first current.

[0082] In step S406, the AFE unit is controlled to provide a voltage, so as to make the electrochemical sensor work normally.

[0083] In step S407, the voltage across the sampling resistor is obtained when the user's tissue fluid enters the electrochemical sensor, so that the electrochemical sensor generates a second current through electrochemical reaction, and the second current flows through the sampling resistor, and is recorded as a second voltage V.

[0084] In step S408, the second current is determined according to the first voltage, the first current and the second voltage.

[0085] In step S409, the blood glucose concentration value of the corresponding user is determined according to the second current.

[0086] It should be noted that the sequence of the collection of the first voltage and the extraction of the user tissue fluid can be that the first voltage is collected first and then the user tissue fluid is extracted, or that the user tissue fluid is extracted first and then the first voltage is collected.

[0087] One embodiment of the present application provides a blood glucose monitoring device. Figure 5 As shown in the figure, the computer device includes a memory 520 and a processor 510. The memory 520 stores a computer program, and the computer program is used to control the processor 510 to perform operations to execute the blood glucose monitoring method provided by any of the above embodiments.

[0088] The processor 510 is used to execute computer instructions, which can be written in an instruction set of an architecture such as x86, Arm, RISC, MIPS, SSE, etc. The memory 520 includes, for example, a ROM (Read-Only Memory), a RAM (Random Access Memory), a non-volatile memory such as a hard disk, etc., which is not limited here.

[0089] The blood glucose monitoring device is a control unit in a continuous blood glucose monitoring device.

[0090] One embodiment of the present application provides a computer readable storage medium, which stores computer program instructions. The computer program instructions are executed by a processor to implement the blood glucose monitoring method provided by any of the above embodiments.

[0091] Each of the embodiments in the specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other. Each embodiment mainly describes the difference from other embodiments.

[0092] The above describes specific embodiments of the present application. Other embodiments are within the scope of the appended claims. In some cases, the acts or steps recited in the claims can be performed in a different order than the order in which they are recited and still achieve desirable results. In addition, the processes depicted in the figures do not necessarily require the particular order shown, or sequential order, to achieve the desired results. In certain implementations, multitasking and parallel processing can be advantageous.

[0093] The embodiments of the present application can be a system, a method, and / or a computer program product. The computer program product can include a computer readable storage medium having computer instructions loaded thereon, which are used to cause a processor to implement various aspects of the embodiments of the present application.

[0094] Computer readable storage media can be tangible storage media which can retain and store instructions for use by an instruction execution device. Computer readable storage media can be, for example, but is not limited to, an electronic storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the foregoing. More specific examples (a non-exhaustive list) of computer readable storage media include the following: 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), a static random access memory (SRAM), a portable compact disc read-only memory (CD-ROM), a digital versatile disk (DVD), a memory stick, a floppy disk, a mechanically encoded device such as punch-cards or raised structures in a groove having instructions recorded thereon, and any suitable combination of the foregoing. A computer readable storage medium, as used herein, is not to be construed as being transitory signals per se, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagating through a waveguide or other transmission media (e.g., light pulses passing through a fiber-optic cable), or electrical signals transmitted through a wire.

[0095] Computer instructions described herein can be downloaded to respective computing / processing devices from a computer readable storage medium or to an external computer or external storage device via a network, for example, the Internet, a local area network, a wide area network and / or a wireless network. The network can comprise copper transmission cables, optical transmission fibers, wireless transmission, routers, firewalls, switches, gateway computers and / or edge servers. A network adapter card or network interface in each computing / processing device receives computer instructions from the network and forwards the computer instructions for storage in a computer readable storage medium within the respective computing / processing device.

[0096] The computer program product of the second aspect can include a computer readable storage medium. The computer readable storage medium can include instructions. The instructions can include one or both of: instructions for causing a computer to implement a method as described above; and instructions for causing a computer to operate based on a system as described above. The computer readable storage medium can include one or more of: a magnetic disk; a magnetic disk drive; a magnetic tape; a magneto-optical drive; a solid state drive; a semiconductor drive; a flash drive; an optical drive; a holographic drive; a holographic medium; a memory stick; a floppy disk; a flexible disk; a hard disk; a hard disk drive; a holographic disk; a holographic disk drive; a RAM drive; a ROM drive; a flash drive; an optical drive; a solid state drive; a solid state drive; a DVD; a DVD drive; a DVD-ROM; a DVD-RW; a DVD+RW; a Blu-Ray disk; a Blu-Ray disk drive; a memory stick; a memory card; an electrical connection via one or more busses; an other appropriate device.

[0097] Embodiments of the present description have been described above, the description is exemplary only, and is not exhaustive or limited to the disclosed embodiments. Many modifications and variations of the described embodiments are possible in light of the above teachings. The choice of words in this document is intended to convey the best of the principles of the embodiments, practical applications, or improvements to the technology in the market, or to enable other ordinary skilled persons in the art to understand the embodiments disclosed herein.

Claims

1. A continuous glucose monitoring device, characterized by, The continuous glucose monitoring device comprises a control unit, a constant current source circuit, a switching switch, an AFE unit, an electrochemical sensor, and a sampling resistor. The electrochemical sensor comprises an extraction electrode, and the AFE unit and the electrochemical sensor both have a three-electrode structure. The AFE unit and the electrochemical sensor are connected through the three-electrode structure. The glucose in the tissue fluid extracted by the extraction electrode reacts electrochemically with the reaction enzyme in the electrochemical sensor.

2. The continuous glucose monitoring device of claim 1, wherein, The current generated by the electrochemical reaction of the electrochemical sensor flows through the sampling resistor.

3. A blood glucose monitoring method characterized by, The first end of the constant current source circuit is connected to the control unit. The second end of the constant current source circuit is connected to the first end of the switching switch. The second end of the sampling resistor is connected to the electrochemical sensor. The control unit and the constant current source circuit are connected through a control switch. The method applied to the continuous glucose monitoring device of claim 1 or 2 comprises the following steps. The switching switch is connected to the first channel to connect the constant current source circuit and the sampling resistor. The constant current source circuit outputs the first current to make the first current flow through the sampling resistor, and the voltage across the sampling resistor is recorded as the first voltage.

4. The method of claim 3, wherein, The constant current source circuit provides the loading voltage for the extraction electrode to extract the tissue fluid of the user based on the loading voltage. The electrochemical sensor generates the second current through the electrochemical reaction, and the second current flows through the sampling resistor.

5. The method of claim 3, wherein, The voltage across the sampling resistor is recorded as the second voltage. The second current is determined according to the first voltage, the first current, and the second voltage. The blood glucose concentration value of the user is determined according to the second current. The IO1 pin of the control unit of the continuous glucose monitoring device is connected to the constant current source circuit. The IO1 pin outputs the high level to make the constant current source circuit output the first current. The IO2 pin of the control unit of the continuous glucose monitoring device is connected to the CTRL pin of the switching switch. The IO2 pin is connected to the first channel of the switching switch, and the IO2 pin is connected to the second channel of the switching switch. The CTRL pin is controlled to output a high level to make the switch connect the first channel, and the CTRL pin is controlled to output a low level to make the switch connect the second channel.

6. The method of claim 3, wherein, The blood glucose concentration value of the corresponding user is determined according to the second current, and the method comprises: Obtaining a corresponding relationship between a current and a blood glucose concentration value; Determining the blood glucose concentration value of the corresponding user according to the second current and the corresponding relationship between the current and the blood glucose concentration value.

7. A blood glucose monitoring device, characterized by, The computer program is stored in the memory and used to control the processor to perform the method according to any one of claims 3 to 6.

8. A computer-readable storage medium having stored thereon computer program instructions, wherein, The computer program instructions are executed by the processor to implement the method according to any one of claims 3 to 6.

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