Patent Application
20230173168
The present invention mainly relates to the field of medical instruments, in particular to a bilaterally driven closed-loop artificial pancreas.
The pancreas in a normal person can automatically monitor the amount of glucose in the blood and automatically secrete the required dosage of insulin/glucagon. However, for diabetic patients, the function of the pancreas is abnormal, and the pancreas cannot normally secrete required dosage of insulin. Therefore, diabetes is a metabolic disease caused by abnormal pancreatic function and also a lifelong disease. At present, medical technology cannot cure diabetes, but can only control the onset and development of diabetes and its complications by stabilizing blood glucose.
Patients with diabetes need to check their blood glucose before injecting insulin into the body. At present, most of the detection methods can continuously detect blood glucose, and send the blood glucose data to the remote device in real time for the user to view. This detection method is called Continuous Glucose Monitoring (CGM), which requires the detection device to be attached to the surface of the patients' skin, and the sensor carried by the device is inserted into the subcutaneous tissue fluid for testing. According to the blood glucose (BG) level, the infusion device, as a closed-loop or semi-closed-loop artificial pancreas, injects the currently required insulin dose.
At present, the detection device and the infusion device are connected to each other to form a closed-loop artificial pancreas with the processing of the program module. While the program module is calculating the insulin infusion dose, total daily dose (TDD) is an important parameter with many determinants, such as physical conditions, physiological conditions, etc.
However, the closed-loop artificial pancreas in prior art needs to be manually input the physical conditions instead of automatically detecting, and the TDD value cannot be accurately obtained, resulting in inaccurate current insulin infusion dose and worsening user experience. And also, the infusion efficiency is lower.
Therefore, in the prior art, there is an urgent need for a closed-loop artificial pancreas that can accurately calculate the current infusion dose with higher infusion efficiency.
Embodiments of the present invention disclose a bilaterally driven closed-loop artificial pancreas, in which the infusion efficiency is higher, and it can accurately calculate the TDD value and the current insulin infusion dose, enhancing user experience.
The invention discloses a bilaterally driven closed-loop artificial pancreas, comprising: a detection module configured to detect blood glucose; an infusion module, including: a drug storage unit; a screw connected to a piston and a driving wheel provided with wheel teeth, respectively, the driving wheel drives the screw to move by rotation, pushing the piston, provided in the drug storage unit, forward; a driving unit cooperating with the driving wheel, the driving unit includes at least two driving portions, the driving unit pivots around a pivot shaft, driving different driving portions in different directions, thus pushing the wheel teeth located on different driving wheel respectively, and rotating the driving wheel; a power unit connected to the driving unit, the power unit outputs two forces in two directions on the driving unit, making the driving unit pivot in two directions around the pivot shaft; and a program module, which is connected to the detention module and the infusion module respectively, is imported the total daily dose algorithm and the current insulin infusion algorithm, and the force output of the power unit is controlled by the program module according to the calculation result of the current insulin infusion algorithm, thereby controlling the infusion module to infuse insulin required.
According to one aspect of this invention, the driving wheel includes at least two sub-wheels.
According to one aspect of this invention, the driving wheel includes two sub-wheels, and the pivot shaft is disposed between the two sub-wheels, one or more of the driving portions are provided on both sides of the driving unit, and each sub-wheel is cooperated with each driving portion.
According to one aspect of this invention, two driving portions are respectively provided on both sides of the driving unit, and the two driving portions on one side of the driving unit are disposed up and down or left and right.
According to one aspect of the present invention, the program module includes a manual input interface or an automatic detection sub-module, and the method for the program module to obtain the insulin dose infused per day by users includes: the insulin dose infused per day by users is manually input into the program module through the manual input interface; or the insulin dose infused per day by users is automatically detected, stored and calculated by the automatic detection sub-module.
According to one aspect of the present invention, the insulin dose infused per day by users includes the total amount of daily infusion dose data, or the bolus and basal data infused in different time periods, or the temporary basal data and the correction bolus data, or the infusion data after different events.
According to one aspect of the present invention, the total daily dose is obtained by calculating the total amount of daily infusion dose data in the previous two or more days according to the total daily dose algorithm, and the total daily dose is the average or median of the insulin dose infused per day by users, and the total daily dose is one variable factor of the current insulin infusion algorithm.
According to one aspect of the present invention, the variable factors of the total daily dose algorithm include one or more of the user's physical activity status, physiological status, psychological status, and meal status.
According to one aspect of the present invention, the physical activity status includes general body stretching, exercise, or sleep.
According to one aspect of the present invention, it further comprises a motion sensor, which is provided in the detection module, the program module or the infusion module, is used to automatically sense the user's physical activity status which can be sent to the program module and is one of the variable factors of the total daily dose algorithm or the current insulin infusion algorithm.
According to one aspect of the present invention, the motion sensor includes a three-axis acceleration sensor or a gyroscope.
According to one aspect of the present invention, any two of the detection module, the program module and the infusion module are connected to each other configured to form a single structure whose attached position on the shin is different from the third module.
According to one aspect of the present invention, the detection module, the program module and the infusion module are connected together configured to form a single structure which is attached on only one position on the skin.
Compared with the prior arts, the technical solution of the present invention has the following advantages:
In the bilaterally driven closed-loop artificial pancreas disclosed herein, a program module, which is connected to the detention module and the infusion module respectively, is imported the total daily dose algorithm and the current insulin infusion algorithm, and the force output of the power unit is controlled by the program module according to the calculation result of the current insulin infusion algorithm, thereby controlling the infusion module to infuse insulin required. The program module is imported into the total daily dose algorithm and the current insulin infusion algorithm. Using the detection data, the insulin dose infused per day by users and the total daily dose alone or in combination makes the current insulin infusion dose more accurate. Secondly, a power unit connected to the driving unit, the power unit outputs two forces in two directions on the driving unit, making the driving unit pivot in two directions around the pivot shaft. The driving unit can drive the driving wheel in two directions for infusion insulin, improving the infusion efficiency.
Furthermore, the program module includes a manual input interface or an automatic detection sub-module, and the method for the program module to obtain the insulin dose infused per day by users includes: the insulin dose infused per day by users is manually input into the program module through the manual input interface; or the insulin dose infused per day by users is automatically detected, stored and calculated by the automatic detection sub-module. The manual input interface or the automatic detection sub-module can be used alone or a combined, which enhances the flexibility using the device. Secondly, with the manual input interface and the automatic detection sub-module used in combination, the data automatically detected and manually input can be combined and compared to make the program module adjust the algorithm in real time, helping to make the calculation result more accurate.
Furthermore, the physical activity status includes general body stretching, exercise or sleep. The artificial pancreas can distinguish normal activities, exercise and sleep, making the artificial pancreas more refined to control blood glucose level.
Furthermore, the motion sensor is provided in the detection module, the program module or the infusion module. The motion sensor provided in the artificial pancreas, not disposed in other structure, can improve the integration of the artificial pancreas as much as possible, reduce the size of the device, and enhance the user experience.
Furthermore, the motion sensor includes a three-axis acceleration sensor or a gyroscope. The three-axis acceleration sensor or gyroscope can sense the body's activity intensity, activity mode or body posture accurately, ultimately improving the accuracy of the calculation result of the infusion dose.
Furthermore, the detection module, the program module and the infusion module are connected together configured to form a single structure which is attached on only one position on the skin. If the three modules are connected as a whole and attached in the only one position, the number of the device on the user skin will be reduced, thereby reducing the interference of more attached devices on user activities. At the same time, it also effectively solves the problem of the poor wireless communication between separating devices, further enhancing the user experience.
As described above, in the prior art device, the TDD value cannot be accurately obtained, resulting in inaccurate current insulin infusion dose and worsening user experience. And also, the infusion efficiency is lower.
The study found that the cause of the above problems is that the driving unit can only drive the driving wheel in one rotation direction, and total daily dose algorithm is not perfect.
In order to solve this problem, the present invention provides a bilaterally driven closed-loop artificial pancreas, in which the driving unit can drive the driving wheel in two directions for infusion insulin, making the infusion efficiency much higher, and it can accurately calculate the TDD value and the current insulin infusion dose, enhancing user experience.
Various exemplary embodiments of the present invention will now be described in detail with reference to the drawings. The relative arrangement of the components and the steps, numerical expressions and numerical values set forth in the embodiments are not to be construed as limiting the scope of the invention.
In addition, it should be understood that, for ease of description, the dimensions of the various components shown in the figures are not necessarily drawn in the actual scale relationship, for example, the thickness, width, length or distance of certain units may be exaggerated relative to other structures.
The following description of the exemplary embodiments is merely illustrative, and is not intended to be in any way limiting the invention and its application or use. The techniques, methods and devices that are known to those of ordinary skill in the art may not be discussed in detail, but such techniques, methods and devices should be considered as part of the specification.
It should be noted that similar reference numerals and letters indicate similar items in the following figures. Therefore, once an item is defined or illustrated in a drawing, it will not be discussed further in the following description of the drawings.
The closed-loop artificial pancreas disclosed in the embodiment of the present invention mainly includes a detection module 100, a program module 101, and an infusion module 102.
The detection module 100 is used to continuously detect the user's real-time blood glucose (BG) level. Generally, the detection module 100 is a Continuous Glucose Monitoring (CGM) for detecting real-time BG, monitoring BG changes, and also sending them to the program module 101.
The program module 101 is used to control the detection module 100 and the infusion module 102. Therefore, the program module 101 is connected to the detection module 100 and the infusion module 102, respectively. Here, the connection refers to a conventional electrical connection or a wireless connection.
The infusion module 102 includes the essential mechanical structures used to infuse insulin and controlled by the program module 101, which will be described in detail below. According to the current insulin infusion dose calculated by the program module 101, the infusion module 102 injects the currently insulin dose required into the user's body. At the same time, the real-time infusion status of the infusion module 102 can also be fed back to the program module 101.
The embodiment of the present invention does not limit the specific positions and connection relationships of the detection module 100, the program module 101 and the infusion module 102, as long as the aforementioned functional conditions can be satisfied.
As in an embodiment of the present invention, the three are electrically connected to form a single structure. Therefore, the three modules can be attached together on only one position of the user's skin. If the three modules are connected as a whole and attached in the only one position, the number of the device on the user skin will be reduced, thereby reducing the interference of more attached devices on user activities. At the same time, it also effectively solves the problem of the poor wireless communication between separating devices, further enhancing the user experience.
As in another embodiment of the present invention, the program module 101 and the infusion module 102 are electrically connected to each other to form a single structure while the detection module 100 is separately provided in another structure. At this time, the detection module 100 and the program module 101 transmit wireless signals to each other to realize mutual connection. Therefore, the program module 101 and the infusion module 102 can be attached on the same position of the user's skin while the detection module 100 is attached on the other position.
As in another embodiment of the present invention, the program module 101 and the detection module 100 are electrically connected to each other forming a single structure while the infusion module 102 is separately provided in another structure. The infusion module 102 and the program module 101 transmit wireless signals to each other to realize mutual connection. Therefore, the program module 101 and the detection module 100 can be attached on the same position of the user's skin while the infusion module 102 is attached on the other position.
As in another embodiment of the present invention, the three are respectively provided in different structures, thus being attached on different position. At this time, the program module 101, the detection module 100 and the infusion module 102 respectively transmit wireless signals to each other to realize mutual connection.
It should be noted that the program module 101 of the embodiment of the present invention also has functions such as storage, recording, and access to the database, thus, the program module 101 can be reused. In this way, not only can the user's physical condition data be stored, but also the production cost and the user's consumption cost can be saved. As described above, when the service life of the detection module 100 or the infusion module 102 expires, the program module 101 can be separated from the detection module 100, the infusion module 102, or both the detection module 100 and the infusion module 102.
Generally, the service lives of the detection module 100, the program module 101 and the infusion module 102 are different. Therefore, when the three are electrically connected to each other to form a single device, the three can also be separated from each other in pairs. For example, if one module expires firstly, the user can only replace this module and keep the other two modules continuous using.
Here, it should be noted that the program module 101 of the embodiment of the present invention may also include multiple sub-modules. According to the functions of the sub-modules, different sub-modules can be respectively assembled in different structure, which is not specific limitation herein, as long as the control conditions of the program module 101 can be satisfied.
In the embodiment of the present invention, the program module 101 is also used to obtain data including the insulin dose infused per day by users. Generally, for artificial pancreas, the current insulin dose required is closely related to the insulin dose infused per day by users in history. Preferably, in the embodiment of the present invention, the insulin dose infused per day by users includes the total amount of daily infusion dose data (d), or the bolus and basal data infused in different time periods, or the temporary basal data and the correction bolus data, or the infusion data after different events.
The program module 101 includes a manual input interface (not shown) or an automatic detection sub-module (not shown). By using the manual input interface or the automatic detection sub-module alone, or using the two combination, the program module 101 can obtain the user's physical condition data. This alone or combination using of these two modules enhances the flexibility in using the device.
For example, in an embodiment of the present invention, with the manual input interface, users can manually input the insulin dose infused per day by users into the program module 101 according to the clinical guidance. In another embodiment of the present invention, the program module 101 has already stored and recorded the user's previous insulin infusion data. With the automatic detection sub-module, the program module 101 can automatically obtain and calculate the insulin dose infused per day by users. Preferably, in the embodiment of the present invention, the user uses the manual input interface in combination with the automatic detection sub-module. At this time, the data automatically detected and the manually input can be combined and compared, making the program module 101 adjust the algorithm in real time for obtaining more accurate calculation outcome.
In other embodiments of the present invention, through the manual input interface, users can also input other information, such as meal information, exercise information, sleep information, and physical condition information into the program module 101, which is not specifically limited herein.
Generally, the purpose of using an artificial pancreas is to stabilize the BG level, that is, an appropriate dose of insulin needs to be infused into the user's body. However, the current insulin infusion dose is closely related to the total daily dose (TDD) which is an important factor influencing the current insulin infusion dose. Therefore, the program module 101 is imported into the total daily dose algorithm and the current insulin infusion algorithm, which are used to calculate the TDD and the current insulin infusion dose, respectively.
The current insulin infusion algorithm is used to calculate the current insulin infusion dose required. In the embodiment of the present invention, there are also many factors affecting the current insulin infusion dose, such as physical activity status, TDD, etc. Preferably, in the embodiment of the present invention, the TDD is one of the variable factors. Therefore, the more accurate the TDD or the more accurate the artificial pancreas sensing the user's activity status, the more accurate the current insulin infusion dose will be. And TDD can be obtained from calculating the aforementioned insulin dose infused per day by users according to the total daily dose algorithm. At the same time, the program module 101 can alone or in combination uses the detection data, the insulin dose infused per day by users and TDD data to calculate the current insulin infusion dose.
There are many factors that affect TDD, and some of them are related to the user's physical condition. Therefore, in the embodiment of the present invention, the variable factors of the total daily dose algorithm include one or more of the user's physical activity status, physiological status, psychological status, and meal status.
Here, the physiological status of the user includes one or more factors of weight, gender, age, disease condition, and menstrual period.
The user's psychological status includes emotional conditions such as anger, fear, depression, hyperactivity, and excitement.
The user's physical activity status includes general body stretching, exercise, or sleep. The artificial pancreas can distinguish normal activities, exercise and sleep, making the artificial pancreas more refined to control BG levels.
As mentioned above, TDD is obtained by the program module 101 by calculating the total amount of daily infusion dose data (d) in the previous two days or more according to the total daily dose algorithm. Preferably, in the embodiment of the present invention, TDD is obtained by the program module 101 by calculating the total amount of daily infusion dose data (d) in the previous seven days. Preferably, TDD is the average value of the total amount of daily infusion dose data (d).
In an embodiment of the present invention, if d7, d6, . . . , d2, d1 respectively represent the total amount of daily infusion dose data in the previous seventh day, the previous sixth day, . . . , the day before yesterday, and yesterday, then:
TDD=(d7+d6+ . . . +d2+d1)/7
that is, TDD is the arithmetic average of the total amount of daily infusion dose data (d).
If the time is much closer to the today, the total amount of daily infusion dose data (d) is much closer to the actual TDD. Therefore, in another embodiment of the present invention, different dn has different weights γn, such as the corresponding weights γ7, γ6, . . . , γ2, γ1, then:
TDD=γ
7
d
7+γ6d6+ . . . +γ2d2
that is, TDD is the weighted average of the total amount of insulin infused per day (a).
It should be noted that the embodiment of the present invention does not limit the statistical method of dn. In yet another embodiment of the present invention, the TDD value can be determined by the median of the total amount of daily infusion dose data (d) in the previous seven days. In another embodiment of the present invention, the maximum value and minimum value of dn may be eliminated firstly, and then the averaging process is performed. Another embodiment of the present invention introduces variance or standard deviation method with discarding points with larger errors firstly and then performing averaging processing. In other embodiments of the present invention, a method of combining weighted average with a sliding data frame may also be used to make the calculation result of TDD more accurate.
Here, it should be noted that the sliding data frame refers to select the data, like from previous five consecutive days, as a data frame for statistics. And according to the passage of time, the data frame as a whole moves backward for several days, but still keeps including data of another previous five consecutive days. For the specific statistical method of the data in the sliding data frame, please refer to the foresaid, which will not be repeated herein.
As mentioned above, both TDD and the current insulin infusion dose are affected by physical activities. Therefore, the closed-loop artificial pancreas also includes a motion sensor (not shown) which is used to sense the user's physical activity. And the program module 101 can receive physical activity status information. The motion sensor can automatically and accurately sense the physical activity status of the user which will be sent to the program module 101, making the calculation result of the TDD or the current insulin infusion dose much more accurate, and enhancing the user experience. At the same time, providing the motion sensor in the module of the artificial pancreas can improve the integration of the artificial pancreas as much as possible, reduce the device size, and enhance the user experience.
The motion sensor is provided in the detection module 100, the program module 101 or the infusion module 102. Preferably, in the embodiment of the present invention, the motion sensor is provided in the program module 101.
It should be noted that the embodiment of the present invention does not limit the number of motion sensors and the installation positions of these multiple motion sensors, as long as the conditions for the motion sensor to sense the user's activity status can be satisfied.
The motion sensor includes a three-axis acceleration sensor or a gyroscope. The three-axis acceleration sensor or gyroscope can more accurately sense the body's activity intensity, activity mode or body posture, which ultimately makes the calculation result of the infusion more accurate. Preferably, in the embodiment of the present invention, the motion sensor is the combination of a three-axis acceleration sensor and a gyroscope.
The screw 1170 is connected to the piston 1160 and the driving wheel 1130, respectively. In the embodiment of the present invention, the driving wheel 1130 is movably mounted on the device base (not shown), and the driving wheel 1130 moves the driving screw 1170 through rotation to advance the piston 1160 disposed in the drug storage unit 1150 to move forward for the purpose of injecting insulin.
The driving unit 1100 is used to drive the driving wheel 1130 to rotate. The driving unit 1100 is movably connected to the device base through the pivot shaft 1120. The power unit 1180 is used to apply a force to the driving unit 1100 leading the driving unit 1100 to pivot. In the embodiment of the present invention, the power unit 1180 is fixedly connected at the top position 1140 of the driving unit 1100, thereby dividing the power unit 1180 into two left and right portions, such as the A′ direction portion and the B′ direction portion in
Specifically, in the embodiment of the present invention, the power unit 1180 is made of shape memory alloy. The A′ direction portion and the B′ direction portion of the shape memory alloy are alternately powered on and off, and a leading force is applied to the driving unit 1100 by a change in the length of the power unit 1180 thereof. The power unit 1180 may be composed of one piece of shape memory alloy, or may be composed of left and right segments (such as the A′ direction segment and the B′ direction segment) of shape memory alloy, and is not specifically limited herein, as long as the force can be applied to lead the driving unit 1100 to pivot.
Here, it should be noted that the power unit 1180 includes, but is not limited to, a shape memory alloy. In other embodiments of the present invention, the power unit 1180 may also be other structures, and the location where the power unit 1180 applies force to the driving unit 1100 is also not limited to the top position 1140, as long as the action of applying a force to the driving unit 1100 can be satisfied to cause the driving unit 1100 to alternately pivot left and right.
As shown in
In the embodiment of the present invention, a plurality of driving portions 1110 are installed on each side of the driving unit 1100. Therefore, a plurality of sub-wheels are also installed on both sides of the driving unit 1100 to cooperate with the driving portions 1110. Specifically, in the embodiment of the present invention, the driving unit 1100 includes four driving portions 1110, which are 1110a, 1110b, 1110c, and 1110d, respectively. 1110a, 1110b are installed on one side of the driving unit 1100, while 1110c, 1110d are installed on the other side of the driving unit 1100. The driving wheel 1130 includes two sub-wheels, one of which cooperates with 1110a, 1110b and the other of which cooperates with 1110c, 1110d.
In the embodiment of the present invention, the two driving portions 1110 on one side of the driving unit 1100 are installed up and down. Here, the up and down settings refer to the up and down positional relationship representations shown in
It should be noted that, in other embodiments of the present invention, these four driving portions may be disposed by other means, such as the two driving portions on one side of the driving unit are disposed left and right, as long as the arms are able to drive the driving wheel to rotate, and is not specifically limited herein.
In a single pivot in the direction A, driving portion 1110a and/or 1110b engage the wheel teeth 1131 to rotate the driving wheel 1130, while 1110c and 1110d can slide on the wheel teeth 1131, but not exert a force for driving the driving wheel 1130 to rotate. And obviously, 1110c slides to the next adjacent driving position firstly. At this time, the driving unit 1100 stops pivoting and the driving portions 1110a and/or 1110b stop engaging the wheel teeth 1131, therefore, the driving wheel 1130 stops rotating. Thus, the driving unit 1100 completes one kind of pivot amplitude. At this time, the driving unit 1100 pivots in the A direction to reach A1 position. The next moment the driving unit 1100 continues to pivot in the A direction, 1110d will slide to the next adjacent driving position. Similarly, the driving unit 1100 completes another kind of pivot amplitude. At this time, the driving unit 1100 still pivots in the A direction to reach A2 position. And the driving unit 1100 completes the whole process of single pivot in the A direction, performing A1 and A2 two pivot amplitudes, respectively, thereby driving the driving wheel 1130 to rotate by two steps, realizing two kinds of infusion modes of the infusion module.
It should be noted that, in the above pivoting process, the driving portion 1110d may firstly slide to the next gear tooth 1131, and then 1110c slides to the next gear tooth 1131, which is not specifically limited herein. Similarly, when the driving unit 1100 pivots in the B direction, it can perform B1 and B2 two pivot amplitudes, respectively.
Obviously, in the whole process of the above-mentioned single pivot in the A direction, the driving unit 1100 undergoes an alternate action of pivot and stop, and the driving portions 1110 alternately engage and stop engaging wheel teeth 1131 to drive the driving wheel 1130 to rotate and stop rotating, realizing two-step rotation of the driving wheel, and finally achieving two infusion modes of the infusion module.
Referring to
Referring to
As with the infusion module of the embodiment of the present invention, when the infusion is started, the amount of insulin required is relatively large, and the patient or the artificial pancreas can select the large A2-B2 pivot amplitude for infusion. After a period of time, the intermediate A1-B1-B2 pivot amplitude or B1-A1-A2 pivot amplitude can be used to reduce the rate of insulin infusion. When the insulin infusion is about to be completed, the patient or the artificial pancreas can switch to the small A1-B1 pivot amplitude to further reduce the infusion rate and achieve precise control of the drug infusion. Of course, the patient or the artificial pancreas can also choose one or several of the modes for infusion, and there are no specific restrictions.
It should be noted that in another embodiment of the present invention, further more driving portions, like three, four, etc., can be disposed on one side of the driving unit. And the total number of driving portions may also be an odd number, such as three, five or more, that is, the numbers of driving portions on both sides of the driving unit are not equal. Moreover, the structural relationship between the different driving portions can be similar to that described above, and no specific restrictions are imposed herein.
As described above, when the driving unit 1200 is output a force in the A′ direction, the driving unit 1200 rotates in the A direction around the pivot shaft 1220, making the driving portion 1210a push the wheel teeth 1231a, thereby driving the driving wheel 1230a to rotate. When the driving unit 1200 is output a force in the B′ direction, the driving unit 1200 rotates in the B direction around the pivot shaft 1220, making the driving portion 1210b push the wheel teeth 1231b, thereby driving the driving wheel 1230b to rotate.
Referring to
In the embodiments of the present invention, the frequency of the force output by the power unit can be changed to further change the pivot frequency of the driving unit, so that the infusion module has a variety of different infusion rates. The user or the artificial pancreas can flexibly select the appropriate infusion rate as needed, making the infusion process flexible and controllable.
In summary, the present invention discloses a bilaterally driven closed-loop artificial pancreas, in which the infusion efficiency is higher, and it can accurately calculate the TDD value and the current insulin infusion dose, enhancing user experience.
While the invention has been described in detail with reference to the specific embodiments of the present invention, it should be understood that it will be appreciated by those skilled in the art that the above embodiments may be modified without departing from the scope and spirit of the invention. The scope of the invention is defined by the appended claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| PCT/CN2020/090152 | May 2020 | CN | international |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/CN2020/111174 | 8/26/2020 | WO |
