River runoff remote sensing measurement method and device, storage medium and electronic equipment

Abstract

The invention belongs to the technical field of hydrodynamic models, and provides a river runoff remote sensing measurement method and device, a storage medium and electronic equipment, and the method comprises the steps: constructing a river terrain; constructing a hydrodynamic model based on the river topography, performing simulation optimization on the hydrodynamic model based on historical data until the hydrodynamic model is stable, and determining an optimal parameter combination; matching at least one key parameter for determining the flow at the curve based on the current river channel form; and according to the at least one key parameter and the hydrodynamic model, determining the flow at the curve in the current river channel form. According to the river runoff remote sensing measurement method provided by the embodiment of the invention, the flow at the curve in the current river form can be accurately determined.

Description

Technical Field

[0001] The present invention belongs to the technical field of hydrodynamic models, and in particular relates to a method, device, storage medium and electronic equipment for remote sensing measurement of river runoff. Background Art

[0002] In traditional runoff measurement, most of them rely on the water level and flow relationship curve of the hydrological station. This traditional flow measurement method has significant limitations. On the one hand, the current hydrological station network density is relatively low, and the station construction requirements are stringent. It is usually necessary to build it in a straight river section, which limits its monitoring ability of complex river systems. On the other hand, the traditional hydrological station construction investment is large, and a lot of manpower, material resources and financial resources are required in the process of station construction and maintenance. In addition, the flow measurement work is not only complicated and cumbersome, but also requires continuous investment from professionals, which further increases the measurement cost.

[0003] Traditional flow measurement methods are difficult to implement for complex rivers and mountainous rivers in areas with insufficient data. Especially in mountainous rivers, the length of the bend section is longer than the straight section, and it is difficult to find measurement points that meet the requirements, so traditional flow measurement methods cannot be used directly. In the bend flow, due to the action of centrifugal force, a lateral gradient will be generated, that is, there is a height difference between the water surface inside and outside the bend. This phenomenon causes the water flow structure in the bend area to become complicated, such as velocity distribution and vortex formation, which makes the limitations of traditional hydrological stations in runoff measurement particularly prominent. However, the bend circulation principle provides a theoretical basis for solving this problem.

[0004] The difficulty in measuring flow at river bends needs to be solved urgently. Summary of the invention

[0005] Based on this, it is necessary to provide a river runoff remote sensing measurement method, device, storage medium and electronic equipment to address the defect that the existing technology cannot accurately measure the flow at the river bend.

[0006] In a first aspect, an embodiment of the present invention provides a method for remote sensing measurement of river runoff, the method comprising:

[0007] Construct river terrain;

[0008] Constructing a hydrodynamic model based on the river topography, and simulating and optimizing the hydrodynamic model based on historical data until the hydrodynamic model reaches a stable state and determines an optimal parameter combination;

[0009] matching at least one key parameter for determining flow at a bend based on current channel morphology;

[0010] The flow rate at the bend under the current river channel morphology is determined based on at least one key parameter and the hydrodynamic model.

[0011] Optionally, at least one key parameter includes: water surface width and lateral gradient.

[0012] Optionally, the at least one key parameter used to determine the flow rate at the bend based on the current river channel morphology matching includes:

[0013] When the current channel morphology is a vertical channel morphology on both sides, at least one key parameter of matching is the first lateral gradient.

[0014] Optionally, determining the flow rate at the bend under the current river channel morphology according to at least one key parameter and the hydrodynamic model includes:

[0015] When the current river channel morphology is a vertical river channel morphology on both sides, a plurality of first lateral gradients at the bends at different water levels obtained by the altimetry satellite are sequentially obtained;

[0016] Obtain each first simulation point;

[0017] Based on the first simulation points, a relationship curve between the first lateral gradient and the flow rate at the bend is plotted through the hydrodynamic model to obtain a corresponding relationship curve, which is recorded as a first relationship curve;

[0018] Acquire a plurality of first lateral gradients at the bend under different water levels obtained based on the first altimetry satellite;

[0019] Based on a plurality of first lateral gradients and the first relationship curve, a first flow rate at a bend under a current river channel morphology is determined.

[0020] Optionally, the at least one key parameter used to determine the flow rate at the bend based on the current river channel morphology matching includes:

[0021] When the current channel morphology is: a channel morphology with one side upright and the other side open, at least one key parameter to be matched includes the first water surface width and the second lateral gradient.

[0022] Optionally, determining the flow rate at the bend under the current river channel morphology according to at least one key parameter and the hydrodynamic model includes:

[0023] Obtain each second simulation point;

[0024] Based on the second simulation points, a relationship curve between the first water surface width, the second lateral gradient and the flow rate at the bend is plotted through the hydrodynamic model to obtain a corresponding relationship curve, which is recorded as a second relationship curve;

[0025] Acquire a plurality of first water surface widths at different water levels obtained based on remote sensing images; and acquire a plurality of second lateral gradients at the bend at different water levels obtained based on a second altimetry satellite;

[0026] Based on multiple first water surface widths, multiple second lateral gradients and the second relationship curve, a second flow rate at the bend under the current river channel morphology is determined.

[0027] Optionally, constructing river terrain includes:

[0028] Constructing the river terrain based on a first low-resolution digital elevation model that has been published; or,

[0029] The river terrain is constructed based on a second digital elevation model with a preset high resolution generated based on the Gaofen 7 image.

[0030] Optionally, constructing river terrain further includes:

[0031] The river terrain is constructed based on the water surface line.

[0032] Optionally, constructing the river topography based on the water surface line includes:

[0033] For a target river channel, obtaining an elevation value at a water edge line of a river channel section, wherein the target river channel includes a straight river channel and a curved river channel;

[0034] Taking the outer envelope as the maximum interpolation range, interpolating the elevation values ​​at each waterside line of the river section to generate corresponding elevation data, wherein the outer envelope is generated based on the fusion processing of the extracted n waterside lines;

[0035] The elevation data is processed by creating a grid from contour lines to generate a corresponding digital grid model;

[0036] The river terrain is constructed based on the digital grid model.

[0037] Optionally, the hydrodynamic model is constructed by performing the following operations:

[0038] Constructing a hydrodynamic model based on the river topography; dividing the hydrodynamic model calculation grid based on the river topography to obtain corresponding calculation grids; and determining the number of grids through a near-wall processing method;

[0039] The large eddy simulation method is used to perform numerical simulation processing on the model, and the model is constructed to obtain the hydrodynamic model.

[0040] Optionally, the simulating and optimizing the hydrodynamic model based on historical data until the hydrodynamic model reaches a stable state and determines an optimal parameter combination includes:

[0041] Comparing the current data with the historical data to obtain a comparison result, wherein the current data and the historical data are both data for the same river section;

[0042] The parameters of the hydrodynamic model are calibrated based on the comparison results, and the root mean square error is used as the objective function. Minimizing the difference between the simulation results and the historical data is used as the goal of simulating and optimizing the hydrodynamic model until the hydrodynamic model reaches a stable state and determines the optimal parameter combination. The calculation formula of the root mean square error is as follows:

[0043]

[0044] Among them, RMSE is the root mean square error, is the analog value, is the observed value, and n is the data point.

[0045] Optionally, after simulating and optimizing the hydrodynamic model based on historical data until the hydrodynamic model is stable and a preferred parameter combination is determined, the method further includes:

[0046] Obtaining the preferred parameter combination;

[0047] The preferred parameter combination is input into the hydrodynamic model for simulation processing, and the simulation result is output and obtained.

[0048] Optionally, before simulating and optimizing the hydrodynamic model based on historical data, the method further includes:

[0049] Upstream boundary conditions are set by historical flow data, and downstream boundary conditions are set by water levels.

[0050] In a second aspect, an embodiment of the present invention provides a river runoff remote sensing measurement device, the device comprising:

[0051] River terrain construction module, used to construct river terrain;

[0052] A model building and optimization module, used to build a hydrodynamic model based on the river topography, and simulate and optimize the hydrodynamic model based on historical data until the hydrodynamic model is stable and an optimal parameter combination is determined;

[0053] A matching module, for matching at least one key parameter for determining flow at a bend based on the current river channel morphology;

[0054] The determination module is used to determine the flow at the bend under the current river channel morphology according to at least one key parameter and the hydrodynamic model.

[0055] According to a third aspect, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed in a computer, the computer is caused to execute the method of the first aspect.

[0056] According to a fourth aspect, an electronic device is provided, comprising a memory and a processor, wherein the memory stores executable code, and when the processor executes the executable code, the method according to the first aspect is implemented.

[0057] In an embodiment of the present invention, a river topography is constructed; a hydrodynamic model is constructed based on the river topography, and the hydrodynamic model is simulated and optimized based on historical data until the hydrodynamic model is stable and an optimal parameter combination is determined; at least one key parameter for determining the flow at the bend is matched based on the current river morphology; and the flow at the bend under the current river morphology is determined based on at least one key parameter and the hydrodynamic model. The river runoff remote sensing measurement method provided by the embodiment of the present invention can accurately determine the flow at the bend under the current river morphology. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] By referring to the following drawings, a more complete understanding of the exemplary embodiments of the present invention can be obtained. The drawings are used to provide a further understanding of the embodiments of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the drawings, the same reference numerals generally represent the same components or steps.

[0059] Figure 1 A flow chart of a river runoff remote sensing measurement method according to an exemplary embodiment of the present invention;

[0060] Figure 2 This is a schematic diagram of the multi-beam geometry of the ICESat-2 satellite;

[0061] Figure 3 It is a schematic structural diagram of a river runoff remote sensing measurement device 300 provided according to an exemplary embodiment of the present invention. DETAILED DESCRIPTION

[0062] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0063] It should be noted that, unless otherwise specified, the technical terms or scientific terms used in the present invention should have the common meanings understood by those skilled in the art to which the present invention belongs.

[0064] In addition, the terms "first" and "second" etc. are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, device, product or equipment that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units that are not listed, or may optionally include other steps or units that are inherent to these processes, methods, products or equipment.

[0065] The embodiments of the present invention provide a river runoff remote sensing measurement method and device, a computer-readable medium, and an electronic device, which are described below with reference to the accompanying drawings.

[0066] The river runoff remote sensing measurement method provided in the embodiment of the present invention, by means of the advantages of satellite remote sensing such as wide spatial coverage, high temporal resolution, non-contact measurement and no restrictions on geographical conditions, constructs river topography and combines the bend circulation principle to build a hydrodynamic model to calculate the flow of bend rivers, thereby providing a new solution for the flow measurement of bend river systems.

[0067] The principle adopted by the river runoff remote sensing measurement method provided in the embodiment of the present invention is the bend circulation principle. The bend circulation principle is explained as follows:

[0068] The rotational movement of the water flow in the bend is projected in a ring shape on the cross section, and it is superimposed on the mainstream and moves forward in a spiral. There may be only one large circulation in the bend, or there may be several circulations of different sizes. The circulation may occupy the entire cross section of the river, or only a part of the cross section of the river.

[0069] When water flows in a curve, centrifugal force is inevitably generated. Under the action of centrifugal force, the water surface on the concave bank of the bend rises and the water surface on the convex bank drops, forming a horizontal gradient of the water surface. The magnitude of the centrifugal force is proportional to the square of the longitudinal flow velocity. The longitudinal flow velocity is unevenly distributed along the water depth. The water surface is large and the river bottom is small. Therefore, the centrifugal force is also distributed along the water depth. The lateral pressure difference caused by the horizontal gradient of the water surface remains unchanged along the water depth. After the two are combined, the force on the upper water body points to the concave bank, and the force on the lower water body points to the convex bank, so that the upper water body flows toward the concave bank and the lower water body flows toward the convex bank, forming a circulation. The flow velocity of the bend circulation is related to factors such as the longitudinal average flow velocity, the curvature radius of the river channel and the water depth.

[0070] Please refer to Figure 1 , which shows a flow chart of a river runoff remote sensing measurement method provided by some embodiments of the present invention, such as Figure 1 As shown, the river runoff remote sensing measurement method may include the following steps:

[0071] Step S101: construct river terrain.

[0072] In one example, constructing a river terrain includes the following steps:

[0073] The river terrain is constructed based on the first digital elevation model with low resolution that has been made public.

[0074] In the actual application scenario, based on the publicly available low-resolution first digital elevation model, the process of constructing the river terrain is as follows:

[0075] The first digital elevation model can provide basic terrain information, but may have certain limitations in accuracy and timeliness.

[0076] The maximum accuracy of existing publicly available DEM (Digital Elevation Model) data is usually 12.5 meters. Although this type of DEM data can provide a wide range of terrain information, its accuracy may not be sufficient to meet high-precision requirements in specific application scenarios, especially for areas with complex terrain such as rivers. This is mainly reflected in: on the one hand, in rivers and their surrounding areas, due to the influence of human activities such as vegetation cover, buildings, bridges, etc., there may be a lot of clutter in the DEM data. These clutters will cause the elevation information of the DEM data in the river channel to be distorted, which will in turn affect the subsequent construction of the hydrodynamic model and flow measurement. On the other hand, a resolution of 12.5 meters may be acceptable for large plain rivers, but for mountain rivers or curved rivers, especially at bends, this accuracy is often not enough to accurately describe the terrain characteristics.

[0077] In addition, the existing DEM data is updated infrequently. When using historical DEM data for modern analysis, the data may no longer be applicable due to surface changes (such as river diversion, land development, etc.), thus affecting the accuracy of the analysis results.

[0078] In another example, building a river terrain includes the following steps:

[0079] The river terrain is constructed based on the second digital elevation model with a preset high resolution generated based on the Gaofen 7 image.

[0080] In the actual application scenario, the process of constructing the river terrain is as follows:

[0081] Step a1: The preprocessing process of GF-7 L1A data includes: orthorectification and image fusion;

[0082] Step a2: Extract DSM (Digital Surface Model) and point cloud data based on SuperView-1 stereo image pair data:

[0083] Regional adjustment: The stereo image pair data is combined with the DEM for regional adjustment to determine the minimum overlap between the two images. When the overlap between two images is less than this value, they will be ignored. The valid range is 0-100, and the default value is 55.

[0084] Matching error value: The smaller the matching error value, the more reliable it is and the less false matches are. The larger the matching error value, the more likely it is to capture details, but it will cause excessive false matches. The default value is usually 15.

[0085] Quality Threshold: Valid range 0-100, default value is 60. Each pixel will be checked for quality, mainly based on the similarity of the matching window image. Quality checking helps to improve the accuracy of pixels located at the edge of the feature.

[0086] Quality check: Setting this value to 0 will result in estimating the height of all matching pixels and generating a large point cloud (LAS) data, which may contain a lot of redundant and erroneous point cloud data. Increasing this threshold will generate fewer matching points (and smaller LAS files), but the point cloud quality is better. The default value of 60 is a reliable and reasonable threshold that can generate high-quality point cloud data. Setting a higher value will result in sparse point cloud density and possible data gaps. Finally, output point cloud data and DSM data: Finally, output point cloud data and DSM data.

[0087] In yet another example, constructing the river terrain further includes the following steps:

[0088] Construct river terrain based on water surface lines.

[0089] In one example, constructing a river terrain based on a water surface line includes the following steps:

[0090] For the target river channel, the elevation value at the water edge of the river channel section is obtained. The target river channel includes a straight river channel and a curved river channel.

[0091] Taking the outer envelope as the maximum interpolation range, the elevation value at each water edge line of the river section is interpolated to generate corresponding elevation data. The outer envelope is generated based on the fusion processing of the extracted n water edges.

[0092] The elevation data is processed by creating a grid from contour lines to generate a corresponding digital grid model;

[0093] Construct river topography based on digital grid model.

[0094] In actual application scenarios, the process of constructing terrain based on water surface lines is as follows:

[0095] High-resolution remote sensing images are used to extract the water edge under different water levels, and the water body index method and other technologies are used to extract the water surface vector of the entire river channel. The center line of the river channel is determined in the geographic information system tool, and a vertical line is generated along the center line. It is superimposed with the water surface vector to obtain the water surface width of the flow section.

[0096] In order to improve the accuracy of terrain construction, the following Figure 2 The ICESat-2 satellite data shown was used to assist in the measurement. The ICESat-2 observatory is equipped with a light counting lidar (ATLAS instrument) as well as GPS, star cameras and ground processing systems, which precisely determine the geodetic longitude, latitude and elevation of the reflection point by measuring the time it takes for a laser pulse to be emitted from ATLAS to reflect from the surface and back to the satellite. The ATLAS laser produces three pairs of left / right light spots on the surface, each pair of which depicts a ground track about 14 meters wide, forming six ground tracks that cover a cross-track distance of about 3 kilometers.

[0097] In these tracks, the left and right light spots in each pair are about 90 meters apart in the cross-track direction and about 2.5 kilometers apart in the along-track direction. High-level ICESat-2 data products (such as ATL03 and above) are organized according to ground track numbers and paired according to left and right light spots, such as ground tracks 1L and 1R, 2L and 2R, 3L and 3R. Through this precise measurement, ICESat-2 can provide high-precision data support for the waterside elevation measurement of river sections, especially in complex bends. These data greatly improve the accuracy and reliability of terrain construction based on water surface lines.

[0098] In one example, a digital raster model is generated by performing the following steps:

[0099] Step b1: Determine the elevation value of the waterside line along the straight river section.

[0100] For straight river sections, if the point measured by the altimeter satellite coincides with the river section, take the elevation value at the intersection of the altimeter satellite point and the waterside line.

[0101] If there is an angle between the altimeter satellite and the flow section, select the elevation value at the intersection of the altimeter satellite point and the flow section. The elevation point at the intersection represents the elevation point on the flow section. Directly assign the elevation value at the intersection to the point on the corresponding water edge of the corresponding flow section, thereby obtaining the elevation values ​​on both sides of the section.

[0102] Step b2: Determine the elevation value of the waterside line of the curved river section.

[0103] At the bend, the existence of centrifugal force will cause a lateral gradient, so the elevation values ​​on the section are different. It is necessary to perform linear fitting based on the existing points and use the fitting relationship to determine the elevation value at the waterside line corresponding to the river section.

[0104] Step b3: interpolation of elevation points.

[0105] Extract n waterside lines, merge them, and generate an outer envelope line. The outer envelope line represents the waterside line with the highest water level. Take the outer envelope line as the maximum interpolation range, interpolate the elevation value on each waterside line, and generate complete elevation data.

[0106] Step b4: Generate digital grid model.

[0107] The interpolated elevation data is used in the geographic information system tool using the "create raster from contour lines" method to generate a digital raster model of the river terrain, which is a digital elevation model.

[0108] In one example, before constructing the river topography, the river runoff remote sensing measurement method provided by the embodiment of the present invention may further include the following steps:

[0109] Determine the river channel state.

[0110] In one example, the river channel plane state is determined by the following steps, as described below:

[0111] Extract the water surface vector of the curved river section and determine the centerline of the river channel;

[0112] Use the tool to create a vertical line to generate a vertical line along the center line;

[0113] Superimpose the vertical line and the water surface vector to obtain the water surface width of the flow section;

[0114] Get the centerline of the river;

[0115] Selecting multiple sampling points at preset intervals on the centerline of the river channel, and calculating the local curvature radius for the multiple sampling points;

[0116] The plane state of the river channel is determined based on the water surface width and local curvature radius of the flow section.

[0117] In one example, the process of determining and obtaining the river channel plane state is specifically described as follows:

[0118] With the help of common remote sensing image processing tools, the remote sensing image radiation calibration and atmospheric correction are carried out, the water surface vector of the curved river section is extracted using the water body index method and other techniques, and the centerline of the river channel is determined using the geographic information system tool.

[0119] Use the "Create Vertical Line" tool to generate a vertical line along the center line, and superimpose it with the water surface vector to calculate the water surface width of the flow section.

[0120] Select sampling points on the center line at appropriate intervals and calculate the local curvature radius using the three-point method. (The curve radius is also called the curve curvature radius, which is the line segment connecting the center of the curve and any point on the curve).

[0121] In one example, before constructing the river topography, the river runoff remote sensing measurement method provided by the embodiment of the present invention may further include the following steps:

[0122] Collect a variety of data, including: multiple satellite data sources, global digital elevation models, multiple altimetry satellite data and multiple measured data from hydrological stations.

[0123] In one example, the data collection process is as follows:

[0124] Step c1: Collect high-resolution optical remote sensing images of the study area, covering a variety of satellite data sources, including but not limited to Landsat series, Sentinel series, Keyhole series, and Gaofen series satellite remote sensing images.

[0125] Step c2: Collect publicly available global digital elevation model data.

[0126] Step c3: Collect the Jason series of altimetry satellites, Icesat_2 altimetry satellites, and T / P altimetry satellites.

[0127] Step c4: Collect measured data from hydrological stations: daily water level data, daily flow data, and measured large-section data.

[0128] Step S102: construct a hydrodynamic model based on the river topography, and simulate and optimize the hydrodynamic model based on historical data until the hydrodynamic model reaches a stable state and determines an optimal parameter combination.

[0129] In one example, a hydrodynamic model is constructed by performing the following operations:

[0130] Constructing a hydrodynamic model based on river topography Based on the river topography, the hydrodynamic model calculation grid is divided to obtain the corresponding calculation grid; and the number of grids is determined by the near-wall processing method;

[0131] The large eddy simulation method is used to perform numerical simulation on the model and construct the model to obtain the hydrodynamic model.

[0132] In actual application scenarios, the process of constructing a hydrodynamic model based on river terrain is as follows:

[0133] Step d1: Division of hydrodynamic model calculation grid.

[0134] The river terrain obtained by the above reconstruction is used to divide the hydrodynamic model calculation grid. Since the wall is affected by viscosity, the wall is encrypted and a structured grid is used, in which the radial boundaries are encrypted. Due to the complex structure of the bend water flow, the bend section grid is encrypted to obtain the calculation grid. A near-wall treatment method similar to the turbulent viscosity model is used to ensure that the near-wall scale y + <5, and then determine the number of grids. The large eddy simulation method is used to numerically simulate the bend and further analyze the hydraulic characteristics of the bend water flow. Combined with the gravity similarity criterion (Froude number similarity) based on gravity, that is, the Froude number Fr that characterizes the ratio of the original model inertial force to gravity;

[0135] Fr=ν / (gl) 0.5 ;

[0136] Where Fr is the Froude number, an important dimensionless number used to describe the ratio of inertial force to gravity in fluid flow.

[0137] ν is the flow velocity, in m / s; g is the acceleration due to gravity, in m / s 2 , l is the characteristic water depth, unit is m.

[0138] Step d2: Construction of the hydrodynamic model.

[0139] Large eddy simulation (LES) decomposes variables into subgrid quantities and resolvable scale quantities through filtering operations. Compared with the time average in Reynolds time average, filtering in large eddy simulation is similar to spatial averaging. Convolution operation is used to implement filtering operation. After filtering the instantaneous variable f, we can get

[0140]

[0141] In the formula, Filtered variable. This symbol indicates a variable that has been filtered. In large eddy simulations (LES), this usually represents the velocity field or other physical quantity after it has been spatially filtered. The purpose of filtering is to separate larger scale eddy structures and ignore small scale turbulence effects.

[0142] f(y) is the original variable. In the integral symbol, f(y) represents the physical quantity at the y position, such as velocity field, pressure field, etc. This physical quantity is the original value without filtering. Through filtering, the small-scale components in the original variable are suppressed and the large-scale components are retained.

[0143] Represents a filter function, a kernel function used to perform convolution operations in space, and is a tool used in large eddy simulation to decompose variables (such as velocity fields) into large and small scales. Commonly used filter functions include box filtering, Gaussian filtering, and spectral truncation filtering.

[0144] x, y are Cartesian coordinates used to represent spatial positions. x, y in the convolution operation refer to the relationship between different variables at different spatial points, and convolution is used to achieve the spatial averaging effect.

[0145] Δ is the filtering scale, which determines which vortices are resolved and which are filtered out during the simulation. A smaller Δ indicates a finer resolution scale.

[0146] Assuming that the filtering process and the derivative process can be exchanged, the Navier-Stokes equation is filtered to obtain the following equation:

[0147]

[0148]

[0149] make And said is the sub-grid force, it can be written as

[0150]

[0151] in,

[0152] x i ,x j (i,j=1,2,3) are Cartesian coordinates; is the velocity component after filtering, i,j=1,2,3 represent the velocity components in the x,y,z directions respectively. In large eddy simulation (LES), filtering is used to extract the large-scale part of eddy motion and ignore the smaller-scale disturbances.

[0153] μ represents the dynamic viscosity coefficient, which refers to the internal friction of the fluid.

[0154] is the fluid pressure after filtering by the filter function;

[0155] τ i j is called the subgrid scale stress tensor, which represents the contribution of small-scale turbulence to fluid momentum due to the averaging of eddy scales. In large eddy simulation, since only larger eddies can be analyzed, the influence of small scales is reflected by this stress tensor, which is a non-closed term and is processed by modeling. It is the component of the filtered strain rate tensor The relationship is:

[0156]

[0157]

[0158]

[0159]

[0160] In the formula, δ ij is the Kronecker delta symbol, used to keep the elements on the diagonal consistent; is the trace term, which represents the mean of the tensor.

[0161] ν T is the subgrid eddy viscosity coefficient, which simulates the viscosity effect in turbulence and is used to describe the momentum diffusion at the subgrid scale. This is part of the Smagorinsky model commonly used in large eddy simulations.

[0162] is the norm of the strain rate tensor and is used to measure the local fluid shear strength.

[0163] S ij The strain rate tensor, which represents the velocity gradient in the fluid, is used to describe the shear and vortex structure of turbulent flow.

[0164] L s The grid size, or filter width, is used to distinguish between large-scale turbulence that can be resolved and small-scale turbulence that needs to be compensated by the model.

[0165] κ is the Karman coefficient; d is the distance between the grid and the nearest wall; V is the grid unit volume;

[0166] c s is the Smagorinsky coefficient, which is an empirical coefficient used to define the turbulence model and is usually taken as about 0.1.

[0167] In one example, the hydrodynamic model is simulated and optimized based on historical data until the hydrodynamic model reaches a stable state and a preferred parameter combination is determined, including the following steps:

[0168] Compare the current data with the historical data to obtain the comparison result. Both the current data and the historical data are for the same river section.

[0169] Based on the comparison results, the parameters of the hydrodynamic model are calibrated, and the root mean square error is used as the objective function. The goal of simulating and optimizing the hydrodynamic model is to minimize the difference between the simulation results and the historical data until the hydrodynamic model reaches a stable state and the optimal parameter combination is determined. The calculation formula of the root mean square error is as follows:

[0170]

[0171] Among them, RMSE is the root mean square error, is the analog value, is the observed value, and n is the data point.

[0172] In one example, after simulating and optimizing the hydrodynamic model based on historical data until the hydrodynamic model is stable and the optimal parameter combination is determined, the river runoff remote sensing measurement method provided by the embodiment of the present invention further includes the following steps:

[0173] Obtaining an optimal parameter combination;

[0174] The optimal parameter combination is input into the hydrodynamic model for simulation processing, and the simulation results are output and obtained.

[0175] In actual application scenarios, when the preferred parameter combination is the optimal parameter combination, the optimal parameter combination can be input into the hydrodynamic model for simulation processing, and the simulation results can be output and obtained. The simulation results are compared with the actual measured results, and the accuracy of the hydrodynamic model simulation results is verified based on the comparison results of the two.

[0176] In addition, a preset proportion of historical data can be randomly selected as verification data, and the corresponding verification data set can be constructed through the verification data.

[0177] In one example, before simulating and optimizing the hydrodynamic model based on historical data, the river runoff remote sensing measurement method provided by the embodiment of the present invention further includes the following steps:

[0178] Upstream boundary conditions are set by historical flow data, and downstream boundary conditions are set by water levels.

[0179] In actual application scenarios, the numerical algorithm and boundary conditions are explained as follows:

[0180] The control equations are discretized by the finite volume method. The convection terms in each control equation adopt the first-order upwind format. The discretized equations are solved by line-by-line scanning iteration using TDMA (Thomas Decomposition Method for Algebraic Systems). The momentum equation and the continuity equation are solved by SIMPLE algorithm to obtain each variable. The flow inlet is given upstream and the water level outlet is given downstream. The VOF method is used to capture the free surface on the upper surface. All solid wall boundaries are considered to be non-slip and are processed by the standard wall function method.

[0181] It should be noted that the above TDMA is an algorithm for solving linear equations, especially for solving tridiagonal matrix equations. In practical application scenarios, TDMA is used to iteratively solve the discretized equations row by row, and this method can be used to efficiently solve the linear equations generated in the fluid dynamics model, thereby effectively reducing computing time and resource consumption.

[0182] The SIMPLE algorithm is a numerical method for calculating flows of any flow rate, and the VOF method is used to deal with two-phase flow problems. This method is based on the fluid volume function C and tracks the phase interface by keeping the interface sharp.

[0183] Step S103: Matching at least one key parameter for determining the flow rate at the bend based on the current river channel morphology.

[0184] In one example, at least one key parameter includes: water surface width, lateral gradient.

[0185] It should be noted that the water surface width is: the water edge line and the river center line are obtained based on remote sensing images, a perpendicular line is drawn to the river center line, and the length of the perpendicular line within the water edge line is used as the water surface width of the flow section, and the perpendicular line is the flow section.

[0186] In actual application scenarios, when at least one key parameter is the water surface width, the river runoff remote sensing measurement method provided by the embodiment of the present invention may further include the following steps:

[0187] The water edge is extracted based on remote sensing images, and the water surface width of the flow section is determined.

[0188] In one example, extracting the water edge based on remote sensing images and determining the water surface width of the flow section include the following steps:

[0189] Through remote sensing images with preset resolution, the water edge lines at different water levels are extracted and processed;

[0190] The water body index method is used to extract the water surface vector of the entire river;

[0191] Determine the centerline of the river channel and generate a vertical line along the centerline of the river channel;

[0192] The vertical line and the water surface vector are superimposed to obtain the water surface width of the flow section.

[0193] Lateral gradient: Based on the water surface elevation obtained by the altimetry satellite, the elevation value is assigned to the water edge line where the flow section is located, and the ratio of the elevation difference between the left and right banks to the water surface width is taken as the lateral gradient.

[0194] In one example, matching at least one key parameter for determining flow at a bend based on the current river channel morphology includes the following steps:

[0195] When the current channel morphology is a vertical channel morphology on both sides, at least one key parameter of matching is the first lateral gradient.

[0196] In actual application scenarios, the process of determining whether the current river channel morphology is a vertical river channel morphology on both sides is described as follows:

[0197] The river bank is relatively fixed, and the width of the water surface does not change much at different water levels. The waterside lines in the dry season and flood season almost completely overlap, and the cross-sectional morphology of the river channel is relatively stable. The waterside lines extracted from remote sensing images show that the positions of the waterside lines in the dry season and flood season are almost the same, which reflects the upright characteristics of the two sides of the river channel, making the water surface width remain relatively constant at different water levels. This river channel morphology is considered to be an upright river channel on both sides.

[0198] In one example, matching at least one key parameter for determining flow at a bend based on the current river channel morphology includes the following steps:

[0199] When the current channel morphology is: a channel morphology with one side upright and the other side open, at least one key parameter to be matched includes the first water surface width and the second lateral gradient.

[0200] In actual application scenarios, the process of determining whether the current river channel morphology is a river channel morphology with one side upright and one side open is as follows:

[0201] The water edge on one side remains unchanged, while the water edge on the other side gradually expands outward as the water level rises. This change causes the width of the water surface to vary at different water levels. The water edge extracted from remote sensing images shows that the water edge on one side basically coincides with the flood season, while the water edge on the other side significantly expands outward during the flood season. This expansion reflects the dynamic changes in the cross-sectional morphology of the river channel. This river channel morphology is considered to be a river channel with one side upright and the other side open.

[0202] It should be noted that in actual application scenarios, the current river channel morphology can be determined based on the water edge and the water surface width of the flow section. For details, please refer to the description of the same or similar parts mentioned above, which will not be repeated here.

[0203] Step S104: Determine the flow rate at the bend under the current river channel morphology according to at least one key parameter and the hydrodynamic model.

[0204] The first case: the current channel shape is determined to be an application scenario where the two sides of the vertical channel shape. In this application scenario, the process of determining the flow at the bend under the current channel shape is as follows:

[0205] In one example, determining the flow at a bend under the current river channel morphology according to at least one key parameter and a hydrodynamic model includes the following steps:

[0206] When the current river channel morphology is a vertical river channel morphology on both sides, a plurality of first lateral gradients at the bends at different water levels obtained by the altimetry satellite are sequentially obtained;

[0207] Obtain each first simulation point;

[0208] Based on each first simulation point, a relationship curve between the first lateral gradient and the flow rate at the bend is plotted through a hydrodynamic model to obtain a corresponding relationship curve, which is recorded as a first relationship curve;

[0209] Acquire a plurality of first lateral gradients at the bend under different water levels obtained based on the first altimetry satellite;

[0210] Based on the multiple first lateral gradients and the first relationship curves, a first flow rate at the bend under the current river channel morphology is determined.

[0211] The second case: the current channel shape is determined to be an application scenario where one side of the channel is upright and the other side is open. In this application scenario, the process of determining the flow at the bend under the current channel shape is as follows:

[0212] In one example, determining the flow at a bend under the current river channel morphology according to at least one key parameter and a hydrodynamic model includes the following steps:

[0213] Obtain each second simulation point;

[0214] Based on each second simulation point, a relationship curve between the first water surface width, the second lateral gradient and the flow rate at the bend is plotted through a hydrodynamic model to obtain a corresponding relationship curve, which is recorded as a second relationship curve;

[0215] Acquire a plurality of first water surface widths at different water levels obtained based on remote sensing images; and acquire a plurality of second lateral gradients at the bend at different water levels obtained based on a second altimetry satellite;

[0216] Based on multiple first water surface widths, multiple second lateral gradients and second relationship curves, a second flow rate at the bend under the current river channel morphology is determined.

[0217] In actual application scenarios, multi-scenario simulations are used to obtain flow values ​​under different river section morphology, water surface width and lateral gradient conditions, and a relationship model between water surface width, lateral gradient and flow is established.

[0218] The first case: for vertical river channels on both sides:

[0219] If the water surface width changes stably, the n waterside lines obtained from the remote sensing image almost overlap, and it is considered to be a vertical river section on both sides. In this scenario, it is determined that the first lateral gradient has a greater impact on the change of the flow at the bend. The relationship curve between the first lateral gradient drawn by each first simulation point of the hydrodynamic model and the flow at the bend (referred to as the first relationship curve) is used. Based on the altimetry satellite, each first lateral gradient at the bend under different water levels and the first relationship curve are obtained to determine the first flow at the bend.

[0220] The second case: For a river channel with one side upright and the other side open:

[0221] If one side of the n waterside lines obtained from the remote sensing image is almost overlapped, and the waterside line on the other side expands outward from the dry season to the flood season, in this scenario, it is determined that the first water surface width and the second lateral gradient have an impact on the flow at the bend. The relationship curve between the first water surface width, the second lateral gradient and the flow at the bend drawn by each second simulation point of the hydrodynamic model (recorded as the second relationship curve). The second flow at the bend is determined based on each first water surface width at different water levels obtained from the remote sensing image and each second lateral gradient at the bend at different water levels obtained by the altimetry satellite, as well as the second relationship curve.

[0222] The river runoff remote sensing measurement method provided by the embodiment of the present invention can accurately determine the flow at the bend under the current river shape.

[0223] In the above-mentioned embodiment, a river runoff remote sensing measurement method is provided, and correspondingly, the present invention also provides a river runoff remote sensing measurement device. The river runoff remote sensing measurement device provided in the embodiment of the present invention can implement the above-mentioned river runoff remote sensing measurement method, and the river runoff remote sensing measurement device can be implemented by software, hardware, or a combination of software and hardware. For example, the river runoff remote sensing measurement device can include integrated or separate functional modules or units to perform the corresponding steps in the above-mentioned methods.

[0224] Please refer to Figure 3 , which shows a schematic diagram of a river runoff remote sensing measurement device provided by some embodiments of the present invention. Since the device embodiment is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment. The device embodiment described below is only illustrative.

[0225] like Figure 3 As shown, the river runoff remote sensing measurement device 300 may include:

[0226] A river terrain construction module 301 is used to construct a river terrain;

[0227] The model building and optimization module 302 is used to build a hydrodynamic model based on the river topography, and simulate and optimize the hydrodynamic model based on historical data until the hydrodynamic model is stable and the optimal parameter combination is determined;

[0228] A matching module 303, for matching at least one key parameter for determining flow at a bend based on the current river channel morphology;

[0229] The determination module 304 is used to determine the flow at the bend under the current river channel morphology according to at least one key parameter and the hydrodynamic model.

[0230] In some implementations of the embodiments of the present invention, at least one key parameter includes: water surface width and lateral gradient.

[0231] In some implementations of the embodiments of the present invention, the matching module 303 is specifically used to:

[0232] When the current channel morphology is a vertical channel morphology on both sides, at least one key parameter of matching is the first lateral gradient.

[0233] In some implementations of the embodiments of the present invention, the determination module 304 is specifically used to:

[0234] When the current river channel morphology is a vertical river channel morphology on both sides, a plurality of first lateral gradients at the bends at different water levels obtained by the altimetry satellite are sequentially obtained;

[0235] Obtain each first simulation point;

[0236] Based on each first simulation point, a relationship curve between the first lateral gradient and the flow rate at the bend is plotted through a hydrodynamic model to obtain a corresponding relationship curve, which is recorded as a first relationship curve;

[0237] Acquire a plurality of first lateral gradients at the bend under different water levels obtained based on the first altimetry satellite;

[0238] Based on the multiple first lateral gradients and the first relationship curves, a first flow rate at the bend under the current river channel morphology is determined.

[0239] In some implementations of the embodiments of the present invention, the matching module 303 is specifically used to:

[0240] When the current channel morphology is: a channel morphology with one side upright and the other side open, at least one key parameter to be matched includes the first water surface width and the second lateral gradient.

[0241] In some implementations of the embodiments of the present invention, the determination module 304 is specifically used to:

[0242] Obtain each second simulation point;

[0243] Based on each second simulation point, a relationship curve between the first water surface width, the second lateral gradient and the flow rate at the bend is plotted through a hydrodynamic model to obtain a corresponding relationship curve, which is recorded as a second relationship curve;

[0244] Acquire a plurality of first water surface widths at different water levels obtained based on remote sensing images; and acquire a plurality of second lateral gradients at the bend at different water levels obtained based on a second altimetry satellite;

[0245] Based on multiple first water surface widths, multiple second lateral gradients and second relationship curves, a second flow rate at the bend under the current river channel morphology is determined.

[0246] In some implementations of the embodiments of the present invention, the river terrain construction module 301 is specifically used to:

[0247] Constructing river terrain based on a first digital elevation model with low resolution that has been made public; or,

[0248] The river terrain is constructed based on the second digital elevation model with a preset high resolution generated based on the Gaofen 7 image.

[0249] In some implementations of the embodiments of the present invention, the river terrain construction module 301 is further specifically used for:

[0250] Construct river terrain based on water surface lines.

[0251] In some implementations of the embodiments of the present invention, the river terrain construction module 301 is specifically used to:

[0252] For the target river channel, the elevation value at the water edge of the river channel section is obtained. The target river channel includes a straight river channel and a curved river channel.

[0253] Taking the outer envelope as the maximum interpolation range, the elevation value at each water edge line of the river section is interpolated to generate corresponding elevation data. The outer envelope is generated based on the fusion processing of the extracted n water edges.

[0254] The elevation data is processed by creating a grid from contour lines to generate a corresponding digital grid model;

[0255] Construct river topography based on digital grid model.

[0256] In some implementations of the embodiments of the present invention, the river runoff remote sensing measurement device 300 may further include:

[0257] Model building module (in Figure 3 ), specifically used for:

[0258] Constructing a hydrodynamic model based on river topography Based on the river topography, the hydrodynamic model calculation grid is divided to obtain the corresponding calculation grid; and the number of grids is determined by the near-wall processing method;

[0259] The large eddy simulation method is used to perform numerical simulation on the model and construct the model to obtain the hydrodynamic model.

[0260] In some implementations of the embodiments of the present invention, the model building and optimization module 302 is specifically used to:

[0261] Compare the current data with the historical data to obtain the comparison result. Both the current data and the historical data are for the same river section.

[0262] Based on the comparison results, the parameters of the hydrodynamic model are calibrated, and the root mean square error is used as the objective function. The goal of simulating and optimizing the hydrodynamic model is to minimize the difference between the simulation results and the historical data until the hydrodynamic model reaches a stable state and the optimal parameter combination is determined. The calculation formula of the root mean square error is as follows:

[0263]

[0264] Among them, RMSE is the root mean square error, is the analog value, is the observed value, and n is the data point.

[0265] In some implementations of the embodiments of the present invention, the river runoff remote sensing measurement device 300 may further include:

[0266] Analog module (in Figure 3 ), which is used to simulate and optimize the hydrodynamic model based on historical data until the hydrodynamic model is stable and the optimal parameter combination is determined, and then obtain the optimal parameter combination; and input the optimal parameter combination into the hydrodynamic model for simulation processing, and output and obtain the simulation result.

[0267] In some implementations of the embodiments of the present invention, the river runoff remote sensing measurement device 300 may further include:

[0268] Boundary condition setting module (in Figure 3 ), which is used to set the upstream boundary conditions through the historical flow data and the downstream boundary conditions through the water level before simulating and optimizing the hydrodynamic model based on the historical data.

[0269] In some embodiments of the embodiments of the present invention, in some embodiments of the embodiments of the present invention, the river runoff remote sensing measurement device 300 provided by the embodiments of the present invention is based on the same inventive concept as the river runoff remote sensing measurement device method provided by the aforementioned embodiments of the present invention and has the same beneficial effects.

[0270] According to another embodiment, there is also provided a computer-readable storage medium having a computer program stored thereon, which, when executed in a computer, causes the computer to execute a combination of Figure 1 The method described.

[0271] According to another embodiment of the present invention, there is also provided an electronic device, comprising a memory and a processor, wherein the memory stores an executable code, and when the processor executes the executable code, the Figure 1 The method described.

[0272] Those skilled in the art should be aware that in one or more of the above examples, the functions described in the present invention can be implemented by hardware, software, firmware or any combination thereof. When implemented by software, these functions can be stored in a computer-readable medium or transmitted as one or more instructions or codes on a computer-readable medium.

[0273] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made on the basis of the technical solution of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for remote sensing measurement of river runoff, characterized in that: The method comprises: Construct river terrain; Constructing a hydrodynamic model based on the river topography, and simulating and optimizing the hydrodynamic model based on historical data until the hydrodynamic model reaches a stable state and determines an optimal parameter combination; matching at least one key parameter for determining flow at a bend based on current channel morphology; The flow rate at the bend under the current river channel morphology is determined based on at least one key parameter and the hydrodynamic model.

2. The river runoff remote sensing measurement method according to claim 1, characterized in that: At least one key parameter includes: water surface width and lateral gradient.

3. The river runoff remote sensing measurement method according to claim 2, characterized in that: The at least one key parameter used to determine the flow rate at the bend based on the current river morphology matching includes: When the current channel morphology is a vertical channel morphology on both sides, at least one key parameter of matching is the first lateral gradient.

4. The river runoff remote sensing measurement method according to claim 3 is characterized in that: Determining the flow rate at the bend under the current river channel morphology according to at least one key parameter and the hydrodynamic model includes: When the current river channel morphology is a vertical river channel morphology on both sides, a plurality of first lateral gradients at the bends at different water levels obtained by the altimetry satellite are sequentially obtained; Obtain each first simulation point; Based on the first simulation points, a relationship curve between the first lateral gradient and the flow rate at the bend is plotted through the hydrodynamic model to obtain a corresponding relationship curve, which is recorded as a first relationship curve; Acquire a plurality of first lateral gradients at the bend under different water levels obtained based on the first altimetry satellite; Based on a plurality of first lateral gradients and the first relationship curve, a first flow rate at a bend under a current river channel morphology is determined.

5. The river runoff remote sensing measurement method according to claim 2, characterized in that: The at least one key parameter used to determine the flow rate at the bend based on the current river morphology matching includes: When the current channel morphology is: a channel morphology with one side upright and the other side open, at least one key parameter to be matched includes the first water surface width and the second lateral gradient.

6. The river runoff remote sensing measurement method according to claim 5, characterized in that: Determining the flow rate at the bend under the current river channel morphology according to at least one key parameter and the hydrodynamic model includes: Obtain each second simulation point; Based on the second simulation points, a relationship curve between the first water surface width, the second lateral gradient and the flow rate at the bend is plotted through the hydrodynamic model to obtain a corresponding relationship curve, which is recorded as a second relationship curve; Acquire a plurality of first water surface widths at different water levels obtained based on remote sensing images; and acquire a plurality of second lateral gradients at the bend at different water levels obtained based on a second altimetry satellite; Based on multiple first water surface widths, multiple second lateral gradients and the second relationship curve, a second flow rate at the bend under the current river channel morphology is determined.

7. The river runoff remote sensing measurement method according to claim 1, characterized in that: The construction of river terrain comprises: Constructing the river terrain based on a first low-resolution digital elevation model that has been published; or, The river terrain is constructed based on a second digital elevation model with a preset high resolution generated based on the Gaofen 7 image.

8. The river runoff remote sensing measurement method according to claim 7, characterized in that: The constructing of river terrain also includes: The river terrain is constructed based on the water surface line.

9. The river runoff remote sensing measurement method according to claim 8, characterized in that: The constructing the river terrain based on the water surface line includes: For a target river channel, obtaining an elevation value at a water edge line of a river channel section, wherein the target river channel includes a straight river channel and a curved river channel; Taking the outer envelope as the maximum interpolation range, interpolating the elevation values ​​at each waterside line of the river section to generate corresponding elevation data, wherein the outer envelope is generated based on the fusion processing of the extracted n waterside lines; The elevation data is processed by creating a grid from contour lines to generate a corresponding digital grid model; The river terrain is constructed based on the digital grid model.

10. The river runoff remote sensing measurement method according to claim 1, characterized in that: The hydrodynamic model is constructed by performing the following operations: Constructing a hydrodynamic model based on the river topography; dividing the hydrodynamic model calculation grid based on the river topography to obtain corresponding calculation grids; and determining the number of grids through a near-wall processing method; The large eddy simulation method is used to perform numerical simulation processing on the model and construct the model to obtain the hydrodynamic model.

11. The river runoff remote sensing measurement method according to claim 1, characterized in that: The simulating and optimizing the hydrodynamic model based on the historical data until the hydrodynamic model reaches a stable state and determines an optimal parameter combination includes: comparing the current data with the historical data to obtain a comparison result, wherein the current data and the historical data are both data for the same river section; The parameters of the hydrodynamic model are calibrated based on the comparison results, and the root mean square error is used as the objective function. Minimizing the difference between the simulation results and the historical data is used as the goal of simulating and optimizing the hydrodynamic model until the hydrodynamic model reaches a stable state and determines the optimal parameter combination. The calculation formula of the root mean square error is as follows: Among them, RMSE is the root mean square error, is the analog value, is the observed value, and n is the data point.

12. The river runoff remote sensing measurement method according to claim 11, characterized in that: After simulating and optimizing the hydrodynamic model based on historical data until the hydrodynamic model is stable and an optimal parameter combination is determined, the method further includes: Obtaining the preferred parameter combination; The preferred parameter combination is input into the hydrodynamic model for simulation processing, and the simulation result is output and obtained.

13. The river runoff remote sensing measurement method according to claim 1, characterized in that: Before simulating and optimizing the hydrodynamic model based on historical data, the method further includes: Upstream boundary conditions are set by historical flow data, and downstream boundary conditions are set by water levels.

14. A river runoff remote sensing measurement device, characterized in that: The device comprises: River terrain construction module, used to construct river terrain; A model building and optimization module, used to build a hydrodynamic model based on the river topography, and simulate and optimize the hydrodynamic model based on historical data until the hydrodynamic model is stable and an optimal parameter combination is determined; A matching module, for matching at least one key parameter for determining flow at a bend based on the current river channel morphology; The determination module is used to determine the flow at the bend under the current river channel morphology according to at least one key parameter and the hydrodynamic model.

15. A computer-readable storage medium, characterized in that: A computer program is stored thereon, and when the computer program is executed in a computer, the computer is caused to execute the method according to any one of claims 1 to 13.

16. An electronic device, characterized in that: The method comprises a memory and a processor, wherein the memory stores executable codes, and when the processor executes the executable codes, the method according to any one of claims 1 to 13 is implemented.

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