Automatic control method and system for a cooking appliance

Abstract

The application provides an automatic control method and system of a cooking device, comprising: when a cooking program is started, obtaining an actual viscosity of food according to a change of current, and executing a first cooking curve of a current stage; judging whether the actual viscosity is less than a standard viscosity; if not, the cooking is ended; if yes, judging whether the actual viscosity is within a first target viscosity threshold range in the case that the first cooking curve is ended; if yes, running a second cooking curve of a next stage; if not, adjusting a cooking temperature of the second cooking curve of the next stage according to the actual viscosity and the first target viscosity threshold range, and running the second cooking curve of the next stage after adjustment; the cooking device can accurately control time and temperature of a cooking utensil in a food cooking process, thereby improving user experience.

Description

Technical Field

[0001] This invention relates to the field of intelligent kitchen appliance control technology, and in particular to automatic control methods and systems for cooking equipment. Background Technology

[0002] When cooking porridge, due to the airtight nature of the cooking equipment and the difficulty in accurately controlling the rice-to-water ratio, the porridge often becomes too thick, too thin, or sticks to the bottom. Because the cooking equipment cannot precisely control the time and temperature during cooking, the results are often unsatisfactory, requiring manual opening of the lid for observation and stirring, leading to a poor user experience. Summary of the Invention

[0003] In view of this, the purpose of the present invention is to provide an automatic control method and system for cooking equipment, which enables the cooking equipment to accurately control the time and temperature of the cooking utensils during the food cooking process, thereby improving the user experience.

[0004] In a first aspect, embodiments of the present invention provide an automatic control method for a cooking device, the method comprising:

[0005] When the cooking program is started, the actual viscosity of the food is obtained based on the change in current, and the first cooking curve of the current stage is executed;

[0006] Determine whether the actual viscosity is less than the standard viscosity;

[0007] If not, then cooking is complete;

[0008] If so, then at the end of the first cooking curve, determine whether the actual viscosity is within the range of the first target viscosity threshold.

[0009] If so, run the second cooking curve for the next stage;

[0010] If not, then based on the actual viscosity and the first target viscosity threshold range, the cooking temperature of the second cooking curve in the next stage is adjusted, and the adjusted second cooking curve in the next stage is run.

[0011] Furthermore, the first cooking curve includes a first cooking time, a first cooking temperature, and a first target viscosity threshold, and the second cooking curve includes a second cooking time, a second cooking temperature, and a second target viscosity threshold. The first cooking curve and the second cooking curve are pre-stored in a standard library of cooking curves.

[0012] Furthermore, if not, the cooking temperature of the second cooking curve in the next stage is adjusted according to the actual viscosity and the range between the first target viscosity threshold, including:

[0013] When the actual viscosity is less than the minimum value of the first target viscosity threshold range, the second cooking temperature of the second cooking curve in the next stage is increased;

[0014] When the actual viscosity is greater than the maximum value of the first target viscosity threshold range, the second cooking temperature of the second cooking curve in the next stage is reduced.

[0015] Furthermore, the cooking temperature in the cooking curve corresponding to each stage is adjusted using the following formula:

[0016] ΔT=γK|λ n -δ n |

[0017] Where ΔT is the adjusted cooking temperature, γ is the ingredient adjustment coefficient, K is the viscosity adjustment coefficient, and λ n δ represents the actual viscosity corresponding to each stage. n The target viscosity threshold corresponding to each stage.

[0018] Furthermore, before obtaining the actual viscosity of the food based on changes in current, the method further includes:

[0019] When the stirring motor drives the stirring device to start working, the current sensor detects the change in current.

[0020] Secondly, embodiments of the present invention provide an automatic control system for a cooking device, the system comprising:

[0021] The acquisition module is used to obtain the actual viscosity of the food based on the change in current when the cooking program is started, and to execute the first cooking curve of the current stage.

[0022] The first judgment module is used to determine whether the actual viscosity is less than the standard viscosity;

[0023] The end module is used to end cooking when the actual viscosity is greater than or equal to the standard viscosity.

[0024] The second judgment module is used to determine whether the actual viscosity is within the first target viscosity threshold range when the first cooking curve ends, provided that the actual viscosity is less than the standard viscosity.

[0025] The operation module is used to run the second cooking curve for the next stage when the actual viscosity is within the range of the first target viscosity threshold.

[0026] The adjustment module is used to adjust the cooking temperature of the second cooking curve in the next stage according to the actual viscosity and the first target viscosity threshold range when the actual viscosity is not within the first target viscosity threshold range, and to run the adjusted second cooking curve in the next stage.

[0027] Furthermore, the first cooking curve includes a first cooking time, a first cooking temperature, and a first target viscosity threshold, and the second cooking curve includes a second cooking time, a second cooking temperature, and a second target viscosity threshold. The first cooking curve and the second cooking curve are pre-stored in a standard library of cooking curves.

[0028] Furthermore, the adjustment module is specifically used for:

[0029] When the actual viscosity is less than the minimum value of the first target viscosity threshold range, the second cooking temperature of the second cooking curve in the next stage is increased;

[0030] When the actual viscosity is greater than the maximum value of the first target viscosity threshold range, the second cooking temperature of the second cooking curve in the next stage is reduced.

[0031] Thirdly, embodiments of the present invention provide an electronic device, including a memory and a processor, wherein the memory stores a computer program that can run on the processor, and the processor executes the computer program to implement the method described above.

[0032] Fourthly, embodiments of the present invention provide a computer-readable medium having processor-executable non-volatile program code that causes the processor to perform the method described above.

[0033] This invention provides an automatic control method and system for a cooking device, comprising: when a cooking program is started, obtaining the actual viscosity of the food based on changes in current, and executing a first cooking curve for the current stage; determining whether the actual viscosity is less than a standard viscosity; if not, ending the cooking process; if yes, determining whether the actual viscosity is within a first target viscosity threshold range after the first cooking curve has ended; if yes, running a second cooking curve for the next stage; if not, adjusting the cooking temperature of the second cooking curve for the next stage based on the actual viscosity and the first target viscosity threshold range, and running the adjusted second cooking curve for the next stage; thereby enabling the cooking device to precisely control the time and temperature of the cooking utensils during food cooking, thereby improving the user experience.

[0034] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention are realized and obtained in accordance with the structures particularly pointed out in the description, claims and drawings.

[0035] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0036] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0037] Figure 1 This is a flowchart of the automatic control method for a cooking device provided in Embodiment 1 of the present invention;

[0038] Figure 2 This is a schematic diagram of the curves relating cooking time, cooking temperature, and viscosity provided in Embodiment 1 of the present invention;

[0039] Figure 3 This is a schematic diagram of the automatic control system of the cooking equipment provided in Embodiment 1 of the present invention.

[0040] icon:

[0041] 1-Acquisition module; 2-First judgment module; 3-End module; 4-Second judgment module; 5-Run module; 6-Adjustment module. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0043] To facilitate understanding of this embodiment, the embodiments of the present invention will be described in detail below.

[0044] Example 1:

[0045] Figure 1 This is a flowchart of an automatic control method for a cooking device provided in Embodiment 1 of the present invention.

[0046] Reference Figure 1 The method includes the following steps:

[0047] Step S101: When the cooking program is started, the actual viscosity of the food is obtained based on the change in current, and the first cooking curve of the current stage is executed.

[0048] Specifically, during the cooking process of porridge, soup, or sauce, the viscosity of the porridge changes in real time. When the standard viscosity is reached, this is the optimal state at the end of cooking, i.e., cooking is complete. When cooking begins, the first cooking curve for the current stage is initiated. The first cooking curve includes a first cooking temperature T1, a first cooking time t1, and a first target viscosity threshold δ1.

[0049] During the cooking process, the stirring device maintains uniform stirring. As the heating time increases, the viscosity of the porridge increases. At this time, the resistance encountered by the stirring device during stirring increases. In order to drive the stirring device to stir evenly, the power of the stirring motor will increase and the current will increase.

[0050] When the porridge-cooking program begins, the stirring motor of the cooking appliance drives the stirring device. At this time, a current sensor detects the generated current and adjusts the current of the stirring device according to the change in porridge viscosity. This change is captured by the current sensor, which also measures the real-time viscosity to obtain the real-time state of the food. Furthermore, the real-time state of the food can be used to adjust the time and temperature of the default cooking curve, thereby generating an adjusted second cooking curve. This second cooking curve is then used to control the second cooking temperature T2, the second cooking time t2, and the second target viscosity threshold δ2 of the cooking appliance to cook the target food.

[0051] Step S102: Determine whether the actual viscosity is less than the standard viscosity; if not, proceed to step S103; if yes, proceed to step S104.

[0052] Step S103, cooking is complete;

[0053] Step S104: If the first cooking curve ends, determine whether the actual viscosity is within the first target viscosity threshold range; if yes, proceed to step S105; if no, proceed to step S106.

[0054] Step S105: Run the second cooking curve for the next stage;

[0055] Step S106: Adjust the cooking temperature of the second cooking curve for the next stage according to the actual viscosity and the first target viscosity threshold range, and run the adjusted second cooking curve for the next stage.

[0056] Specifically, when the first cooking curve ends and the actual viscosity is outside the first target viscosity threshold range, the cooking temperature of the second cooking curve in the next stage is adjusted based on the actual viscosity and the range between the actual viscosity and the first target viscosity threshold. By adjusting the food's cooking curve through real-time viscosity monitoring, this solves the problem of inaccurate control of cooking time and temperature, which leads to unsatisfactory cooking results. Cooking ends when the actual viscosity reaches the standard viscosity δ. The cooking time can be reduced or extended based on the standard viscosity. When the actual viscosity is less than the standard viscosity, the cooking temperature is adjusted first; when the actual viscosity equals the standard viscosity, cooking ends prematurely.

[0057] Furthermore, the first cooking curve includes a first cooking time, a first cooking temperature, and a first target viscosity threshold, and the second cooking curve includes a second cooking time, a second cooking temperature, and a second target viscosity threshold. The first cooking curve and the second cooking curve are pre-stored in a standard library of cooking curves.

[0058] Furthermore, step S106 includes the following steps:

[0059] Step S201: When the actual viscosity is less than the minimum value of the first target viscosity threshold range, increase the second cooking temperature of the second cooking curve in the next stage.

[0060] Step S202: When the actual viscosity is greater than the maximum value of the first target viscosity threshold range, the second cooking temperature of the second cooking curve in the next stage is reduced.

[0061] Specifically, each standard cooking curve is set with a standard viscosity δ, and each cooking stage corresponds to a target viscosity threshold δ1, δ2, ..., δn. When the actual viscosity reaches the standard viscosity δ during the cooking process, the cooking is immediately stopped.

[0062] If the standard viscosity δ is not reached, at the end of each cooking stage, it is determined whether the target viscosity threshold for that stage has been reached. If the actual viscosity is less than the minimum value of the first target viscosity threshold range, the second cooking temperature of the second cooking curve for the next stage is increased; if the actual viscosity is greater than the maximum value of the first target viscosity threshold range, the second cooking temperature of the second cooking curve for the next stage is decreased. Where δ1, δ2, ..., δn are all less than δ.

[0063] Reference Figure 2When the first cooking curve is adjusted to the second cooking curve, and the cooking time reaches the cooking time of the first cooking curve, it is determined whether the actual viscosity of the first cooking curve is within the first target viscosity threshold range. If so, the second cooking curve is started. When the second cooking curve finishes running, it is determined whether the actual viscosity of the second cooking curve has reached the second target viscosity threshold. If it has not reached the minimum target viscosity threshold, the cooking temperature of the third cooking curve needs to be adjusted to reach the standard viscosity of the food and complete the cooking process. The relationship between viscosity threshold and cooking temperature adjustment is shown in Table 1.

[0064] Table 1

[0065]

[0066] As shown in Table 1, the cooking temperature is adjusted according to the magnitude of the deviation between the target viscosity threshold range and the actual viscosity; the larger the deviation, the more the cooking temperature is adjusted. When λ is less than the minimum value of the target viscosity threshold range, the deviation is compared with the minimum value of the target viscosity threshold range; when λ is greater than the maximum value of the target viscosity threshold range, the deviation is compared with the maximum value of the target viscosity threshold range.

[0067] Furthermore, the cooking temperature in the cooking curve corresponding to each stage is adjusted using formula (1):

[0068] ΔT=γK|λ n -δ n | (1)

[0069] Where ΔT is the adjusted cooking temperature, K is the viscosity adjustment coefficient, and λ n The actual viscosity corresponding to each stage, δ n The target viscosity threshold corresponds to each stage. K is positively correlated with the target viscosity threshold; the larger the target viscosity threshold, the larger the value of K. γ is the ingredient adjustment coefficient, which varies for different ingredients.

[0070] After each cooking cycle, the corresponding cooking data is recorded in the database and stored for future reference. Users can select their desired viscosity level the next time they use the cooking curve program. Alternatively, this application can also directly determine the viscosity using a viscosity sensor.

[0071] Furthermore, prior to step S101, the method further includes the following steps:

[0072] Step S301: When the stirring motor drives the stirring device to start working, the current sensor detects the change in current.

[0073] Specifically, the stirring motor of the cooking appliance drives the stirring device when the porridge cooking program starts. At this time, the current sensor detects the change in current and obtains the actual viscosity of the food based on the change in current. According to the viscosity-current correspondence database, different viscosity grades have corresponding current ranges.

[0074] Furthermore, the relationship between viscosity and current can also be derived from formula (2):

[0075]

[0076] Where δ is the dynamic viscosity value (m·Pa·s) output by the constant speed torque sensor; v is the rotational speed, which is a constant (r·min). －1 k is the rotation constant determined by the structural dimensions of the inner and outer cylinders (in cm); Torque (current) sensitivity (g·cm·mA) of torque motor －1 I is the load current output by the torque motor (mA); I0 is the no-load current of the torque motor (mA).

[0077] This invention provides an automatic control method for a cooking device, comprising: when a cooking program is started, obtaining the actual viscosity of the food based on changes in current, and executing a first cooking curve for the current stage; determining whether the actual viscosity is less than a standard viscosity; if not, ending the cooking process; if yes, determining whether the actual viscosity is within a first target viscosity threshold range after the first cooking curve has ended; if yes, running a second cooking curve for the next stage; if not, adjusting the cooking temperature of the second cooking curve for the next stage based on the actual viscosity and the first target viscosity threshold range, and running the adjusted second cooking curve for the next stage; thereby enabling the cooking device to precisely control the time and temperature of the cooking utensils during food cooking, thereby improving the user experience.

[0078] Example 2:

[0079] Figure 3 This is a schematic diagram of the automatic control system of the cooking equipment provided in Embodiment 1 of the present invention.

[0080] Reference Figure 3 The system includes:

[0081] Module 1 is used to obtain the actual viscosity of the food based on the change in current when the cooking program is started, and to execute the first cooking curve of the current stage.

[0082] The first judgment module 2 is used to determine whether the actual viscosity is less than the standard viscosity;

[0083] End module 3 is used to end cooking when the actual viscosity is greater than or equal to the standard viscosity;

[0084] The second judgment module 4 is used to determine whether the actual viscosity is within the first target viscosity threshold range when the first cooking curve ends, in the case where the actual viscosity is less than the standard viscosity.

[0085] Module 5 is used to run the second cooking curve for the next stage when the actual viscosity is within the first target viscosity threshold range;

[0086] The adjustment module 6 is used to adjust the cooking temperature of the second cooking curve in the next stage according to the actual viscosity and the first target viscosity threshold range when the actual viscosity is not within the first target viscosity threshold range, and to run the adjusted second cooking curve in the next stage.

[0087] Furthermore, the first cooking curve includes a first cooking time, a first cooking temperature, and a first target viscosity threshold, and the second cooking curve includes a second cooking time, a second cooking temperature, and a second target viscosity threshold. The first cooking curve and the second cooking curve are pre-stored in a standard library of cooking curves.

[0088] Furthermore, adjustment module 6 is specifically used for:

[0089] When the actual viscosity is less than the minimum value of the first target viscosity threshold range, increase the second cooking temperature of the second cooking curve in the next stage;

[0090] When the actual viscosity is greater than the maximum value of the first target viscosity threshold range, the second cooking temperature of the second cooking curve in the next stage is reduced.

[0091] This invention provides an automatic control system for a cooking device, comprising: when a cooking program is started, obtaining the actual viscosity of the food based on changes in current, and executing a first cooking curve for the current stage; determining whether the actual viscosity is less than a standard viscosity; if not, ending the cooking process; if yes, determining whether the actual viscosity is within a first target viscosity threshold range after the first cooking curve has ended; if yes, running a second cooking curve for the next stage; if not, adjusting the cooking temperature of the second cooking curve for the next stage based on the actual viscosity and the first target viscosity threshold range, and running the adjusted second cooking curve for the next stage; thereby enabling the cooking device to precisely control the time and temperature of the cooking utensils during food cooking, thereby improving the user experience.

[0092] This invention also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps of the automatic control method for the cooking device provided in the above embodiments.

[0093] This invention also provides a computer-readable medium having processor-executable non-volatile program code, on which a computer program is stored, and which, when run by a processor, executes the steps of the automatic control method for the cooking apparatus described above.

[0094] The computer program product provided in the embodiments of the present invention includes a computer-readable storage medium storing program code. The instructions included in the program code can be used to execute the methods described in the preceding method embodiments. For specific implementation, please refer to the method embodiments, which will not be repeated here.

[0095] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working process of the system and apparatus described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0096] Furthermore, in the description of the embodiments of the present invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the present invention based on the specific circumstances.

[0097] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention, essentially, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0098] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0099] Finally, it should be noted that the above-described embodiments are merely specific implementations of the present invention, used to illustrate the technical solutions of the present invention, and not to limit it. The scope of protection of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments within the technical scope disclosed in the present invention, or make equivalent substitutions for some of the technical features; and these modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. An automatic control method for a cooking device, characterized in that, The method includes: When the cooking program is started, the actual viscosity of the food is obtained based on the change in current, and the first cooking curve of the current stage is executed; Determine whether the actual viscosity is less than the standard viscosity; If not, then cooking is complete; If so, then at the end of the first cooking curve, determine whether the actual viscosity is within the range of the first target viscosity threshold. If so, run the second cooking curve for the next stage; If not, then based on the actual viscosity and the first target viscosity threshold range, the cooking temperature of the second cooking curve in the next stage is adjusted, and the adjusted second cooking curve in the next stage is run. The cooking temperature in the cooking curve corresponding to each stage is adjusted using the following formula: ΔT=γK|λ n -d n | Where ΔT is the adjusted cooking temperature, γ is the ingredient adjustment coefficient, K is the viscosity adjustment coefficient, and λ n δ represents the actual viscosity corresponding to each stage. n The target viscosity threshold is the value corresponding to each stage.

2. The automatic control method for cooking equipment according to claim 1, characterized in that, The first cooking curve includes a first cooking time, a first cooking temperature, and a first target viscosity threshold. The second cooking curve includes a second cooking time, a second cooking temperature, and a second target viscosity threshold. The first cooking curve and the second cooking curve are pre-stored in a standard library of cooking curves.

3. The automatic control method for cooking equipment according to claim 1, characterized in that, If not, then based on the actual viscosity and the range of the first target viscosity threshold, the cooking temperature of the second cooking curve in the next stage is adjusted, including: When the actual viscosity is less than the minimum value of the first target viscosity threshold range, the second cooking temperature of the second cooking curve in the next stage is increased; When the actual viscosity is greater than the maximum value of the first target viscosity threshold range, the second cooking temperature of the second cooking curve in the next stage is reduced.

4. The automatic control method for cooking equipment according to claim 1, characterized in that, Before obtaining the actual viscosity of the food based on changes in current, the method further includes: When the stirring motor drives the stirring device to start working, the current sensor detects the change in current.

5. An automatic control system for a cooking device, characterized in that, The system includes: The acquisition module is used to obtain the actual viscosity of the food based on the change in current when the cooking program is started, and to execute the first cooking curve of the current stage. The first judgment module is used to determine whether the actual viscosity is less than the standard viscosity; The end module is used to end cooking when the actual viscosity is greater than or equal to the standard viscosity. The second judgment module is used to determine whether the actual viscosity is within the first target viscosity threshold range when the first cooking curve ends, provided that the actual viscosity is less than the standard viscosity. The operation module is used to run the second cooking curve for the next stage when the actual viscosity is within the range of the first target viscosity threshold. An adjustment module is used to adjust the cooking temperature of the second cooking curve in the next stage according to the actual viscosity and the first target viscosity threshold range when the actual viscosity is not within the first target viscosity threshold range, and to run the adjusted second cooking curve in the next stage. The cooking temperature in the cooking curve corresponding to each stage is adjusted using the following formula: ΔT=γK|λ n -d n | Where ΔT is the adjusted cooking temperature, γ is the ingredient adjustment coefficient, K is the viscosity adjustment coefficient, and λ n δ represents the actual viscosity corresponding to each stage. n The target viscosity threshold is the value corresponding to each stage.

6. The automatic control system of the cooking equipment according to claim 5, characterized in that, The first cooking curve includes a first cooking time, a first cooking temperature, and a first target viscosity threshold. The second cooking curve includes a second cooking time, a second cooking temperature, and a second target viscosity threshold. The first cooking curve and the second cooking curve are pre-stored in a standard library of cooking curves.

7. The automatic control system of the cooking equipment according to claim 5, characterized in that, The adjustment module is specifically used for: When the actual viscosity is less than the minimum value of the first target viscosity threshold range, the second cooking temperature of the second cooking curve in the next stage is increased; When the actual viscosity is greater than the maximum value of the first target viscosity threshold range, the second cooking temperature of the second cooking curve in the next stage is reduced.

8. An electronic device comprising a memory and a processor, wherein the memory stores a computer program executable on the processor, characterized in that, When the processor executes the computer program, it implements the method described in any one of claims 1 to 4.

9. A computer-readable medium having processor-executable non-volatile program code, characterized in that, The program code causes the processor to execute the method described in any one of claims 1 to 4.

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