Method, device and program for simulating turbidity of hill-plain polder area composite drainage basin

Abstract

The invention relates to a method, equipment and a program for simulating turbidity of a hill-plain polder area composite watershed. The method comprises the following steps: establishing a linear relation model by taking ISS concentration, algae concentration and other OSS concentration as independent variables and turbidity as a dependent variable; the method comprises the following steps: simulating land surface circulation of an upstream hilly area by using an SWAT model, simulating land surface circulation of a downstream polder area by using a PHPS model, respectively outputting land surface produced water and produced suspended solids of the upstream hilly area and the downstream polder area to an MIKE11 model, and simulating river network convergence of water and suspended solids by using a water power module and a convection diffusion module of the MIKE11 model. Obtaining the spatial and temporal distribution of the suspended matter concentration in the watershed water body, disassembling the simulated suspended matter concentration, substituting the disassembled suspended matter concentration into the linear relation model, and dynamically inverting the spatial and temporal change process of the watershed turbidity. According to the method, a model tool can be provided for refined simulation and prediction of the river turbidity and the suspended solids of the composite drainage basin, and a scientific basis is provided for targeted drainage basin water environment depth improvement and land utilization optimization.

Description

Technical Field

[0001] The invention belongs to the technical field of non-point source pollution load simulation, and in particular relates to a turbidity simulation method, equipment and program for a hill-plain embankment composite watershed. Background Art

[0002] Turbidity is an important indicator for assessing water quality. It reflects the concentration of suspended matter (TSS) in water, such as sediments, organic matter and inorganic matter. Turbidity has a significant impact on the vertical distribution and productivity of phytoplankton, aquatic animals and plants by affecting the light intensity in the water, thereby affecting the quality of the aquatic ecosystem. The hill-plain composite basin has the dual interference of complex natural conditions and strong artificial control. Most of these basins face the problems of turbid water and serious soil erosion. Turbidity monitoring and the formulation of reasonable turbidity control plans can solve the relevant problems.

[0003] Traditional turbidity monitoring methods rely on on-site point data collection, but due to the number of monitoring points and sampling frequency, it is difficult to fully reflect the spatiotemporal changes in water turbidity. Satellite remote sensing monitoring has a wide coverage and low cost, but its spectral inversion model is easily limited by monitoring frequency and weather factors. Turbidity simulation based on the hydrological and hydrodynamic processes of the basin can not only analyze the turbidity and suspended matter change process under the changing environment from a mechanism perspective, improve the spatiotemporal resolution of turbidity inversion, but also transform the water turbidity process into the terrestrial suspended matter process, providing technical support for identifying the key pollution source areas and hot spots of turbidity. However, existing hydrological models are mostly used to simulate hydrological processes in mountainous areas, often ignoring the complex hydrological conditions of the downstream plain embankment area and the impact of strong human activities on river suspended matter and turbidity changes. At present, there is still a lack of turbidity simulation and prediction methods for hill-plain embankment complex basins. How to quantitatively analyze the spatiotemporal change trend of suspended matter in the water body of the complex basin and propose reasonable turbidity control targets has become an urgent requirement for carrying out integrated water and land basin turbidity control work under the background of the "River Chief System". Summary of the invention

[0004] The first purpose of the present invention is to provide a turbidity simulation method for a hilly-plain embankment complex watershed. Relying on hydrological models of hilly areas and plain embankments, river hydrodynamic models, GIS spatial analysis and other technologies, the suspended matter-turbidity relationship is analyzed, and a comprehensive hydrological-hydrodynamic-turbidity model framework for a complex watershed is constructed. The spatiotemporal variation process of suspended matter and turbidity in the watershed is dynamically inverted, providing key technical support for turbidity control in complex watersheds.

[0005] To achieve the above object, the present invention adopts the following technical solution:

[0006] A turbidity simulation method for a hill-plain composite watershed, comprising:

[0007] With the concentration of inorganic suspended solids (ISS), algae, and organic suspended particles (OSS) other than algae as independent variables and turbidity as dependent variable, a linear relationship model was established, and the model parameters were calibrated using measured data.

[0008] The SWAT model was used to simulate the land surface circulation in the upstream hilly area, and the PHPS model was used to simulate the land surface circulation in the downstream polder area, and the land surface water and suspended solids production in the upstream hilly area and the downstream polder area were output respectively; based on the land surface water and suspended solids production output by the SWAT model and the PHPS model, the hydrodynamic module and convection-diffusion module of the MIKE11 model were used to simulate the river network confluence of water and suspended solids, and the spatiotemporal distribution of suspended solids concentration in the watershed water body was obtained;

[0009] The ratios of inorganic suspended matter ISS concentration, algae concentration, and organic suspended particulate matter OSS concentration other than algae in the measured suspended matter components in the river channel of the basin are obtained, the suspended matter concentration simulated by the MIKE11 model is decomposed according to the ratios of the components, and the linear relationship model of the calibrated model parameters is used to obtain the spatiotemporal distribution of water turbidity.

[0010] As a preferred implementation, the SWAT model divides the basin into multiple sub-basins through the river network system for simulation, and the PHPS model divides each polder area into a separate sub-basin for simulation;

[0011] The land surface water and suspended solids produced by the SWAT model and the PHPS model are used as the input boundary conditions of the water volume and suspended solids of the MIKE11 river grid in the form of point sources at the outlet of the sub-basin, and the MIKE11 model is used to simulate the river network confluence of water and suspended solids.

[0012] As a preferred implementation, the method also includes, using the PHPS model to simulate the water consumption and time of irrigation in the polder area, obtaining the irrigation water volume, and adding the calculated result of the irrigation water volume as a loss item to the boundary file of the MIKE11 model.

[0013] As a preferred embodiment, the method further includes, considering the interaction between the groundwater in the polder area and the river outside the polder, adding a groundwater exchange coupling module inside and outside the polder in the coupling calculation of the SWAT model and the MIKE11 model, and its control equation is:

[0014]

[0015] In the formula, is the exchange amount of the two waters; m is the permeability coefficient of the soil in the polder area and the bottom mud of the river outside the polder; is the water level of the river outside the dike, which is obtained by simulating the river water level using the MIKE11 model; is the groundwater level in the polder area, obtained by PHPS model simulation;

[0016] The two water exchange amounts are used as input items or output items of the water balance control equation of the SWAT model and the MIKE11 model.

[0017] As a preferred implementation, the method further includes obtaining an increase in the suspended matter load in the river caused by river navigation, and adding an equal amount of suspended matter load as a boundary condition to the MIKE11 model.

[0018] Furthermore, the method for obtaining the increase in the suspended matter load in the river caused by river navigation is as follows:

[0019] Based on the monitoring data of daily river ship volume and suspended solids concentration, a fitting relationship curve between the two is obtained, and the increased suspended solids concentration of each ship is estimated based on the slope of the curve;

[0020] Combined with the daily river vessel volume data, the concentration of suspended solids in the river channel increased by daily shipping was calculated;

[0021] The increase in suspended matter load in the river caused by shipping was estimated based on the increased suspended matter concentration and runoff caused by daily shipping.

[0022] As a preferred embodiment, the proportion of suspended matter components measured in the river is the proportion of seasonal average suspended matter components. The proportion of seasonal average suspended matter components refers to the average proportion of suspended matter components in each season calculated based on the concentration values ​​of each component of suspended matter measured in the river under long-term monitoring. Accordingly, when the linear model is used for suspended matter calculation, the suspended matter concentration output by the coupling model is decomposed into simulated values ​​according to the proportion corresponding to the season, and substituted into the linear model to obtain the corresponding turbidity.

[0023] The present invention has the following beneficial effects:

[0024] (1) The SWAT-PHPS-MIKE11 (suspended matter-turbidity relationship model) coupling model constructed by the present invention and the method fully considers the different natural hydrological and artificial control conditions in hilly areas and plain areas, and can provide a model tool for the refined simulation and prediction of turbidity and suspended matter in complex river basins, and provide a scientific basis for the targeted deep improvement of the water environment in the basin and the optimization of land use.

[0025] (2) The suspended matter-turbidity relationship model of the present invention quantifies the contribution of each component of suspended matter to turbidity, and considers the impact of algae in water pollution. The organic suspended particles are decomposed into algae and other organic components as two independent variables for the construction of the suspended matter-turbidity relationship model.

[0026] (3) The present invention considers that the plain polder area is mainly composed of rice fields, and water exchange between the polder area and the river outside the polder area must occur frequently to meet the requirements of rice growth irrigation and flood control and drainage in the polder area. Therefore, the PHPS model of the plain polder area is a two-way coupling model with MIKE11, and a new water module / boundary condition is introduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a flow chart of the method of the present invention.

[0028] Figure 2 This is the simulation result of suspended matter in the Xitiaoxi River Basin in a certain embodiment.

[0029] Figure 3 It is the simulation result of river turbidity in the Xitiaoxi River Basin in a certain embodiment. DETAILED DESCRIPTION

[0030] In order to make the technical solution more clearly understood by those skilled in the art, the method of the present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0031] Example 1

[0032] This embodiment specifically describes the process of the method of the present invention. Figure 1 As shown, including:

[0033] Construction of S100 composite watershed geospatial dataset

[0034] The data required for the model's numerical simulation mainly come from field surveys and monitoring and existing basic geographic data obtained from various databases or field surveys.

[0035] S110 Field Survey Monitoring

[0036] Field survey and monitoring mainly include three aspects: periodic hydrology, water quality, soil and vegetation data. The method of obtaining hydrology and water quality data is: by setting up points on the main river and important tributaries, and selecting the pump-front ponds in typical embankment areas to set up water sample collection points and water level monitoring points, including turbidity, suspended matter content, suspended inorganic matter and suspended organic matter content, chlorophyll a, suspended matter particle size distribution, total dissolved solids, flow rate, water depth, etc. The method of obtaining soil and vegetation data is: setting up soil samples and vegetation points in the basin, and collecting data including soil bulk density, particle size distribution, moisture content, vegetation type, coverage, density, etc. In addition, automatic monitoring data of ship traffic in key waterway sections such as locks are also collected.

[0037] S120 Basic Geographic Data Collection

[0038] The basic geographic data collected in this step include continuous meteorological, hydrological, topographic, water quality, fertilizer application, planting system, population and livestock and poultry breeding data. In this embodiment, the meteorological data comes from the National Meteorological Science Data Center and the Hydrological Yearbook. The topographic data comes from the Geospatial Data Cloud. The land use type data comes from GlobeLand30. Water quality data is obtained from the National Water Quality Automatic Comprehensive Supervision Platform. The fertilizer application data, planting system, and livestock and poultry breeding data come from field surveys, existing papers or statistical yearbooks and other materials. The population data comes from the global 100-meter population distribution data.

[0039] Analysis of factors affecting S200 turbidity and construction of suspended solids-turbidity relationship model

[0040] Turbidity is closely related to suspended solids, and the relationship between the two is affected not only by mass concentration but also by suspended solids components. Previous studies have only focused on the relationship between turbidity and suspended solids concentration, lacking the quantification of the effects of each component on turbidity. Suspended solids (TSS) include organic suspended particles (OSS) and inorganic suspended solids (ISS). OSS affects turbidity differently from ISS, and the two have different optical properties. In addition, algae is also an important influencing factor in water pollution control, so the present invention subdivides OSS into algae and other organic components as two independent variables.

[0041] In order to quantify the contribution of each component of suspended matter to turbidity, the present invention selects the concentration of inorganic suspended matter (ISS), algae, and other organic suspended particulate matter (OSS) as independent variables and turbidity as the dependent variable to establish a multivariate linear equation.

[0042] Turbidity = a1·C ISS +a2·C Algae +a3·C OSS-Algae +b

[0043] Among them, a1, a2, a3 are the coefficients of the respective variables, which are calibrated using the measured data; b is the intercept, which represents the degree to which turbidity is affected by other factors, which is calibrated using the measured data; C ISS , C Algae , C OSS-Algae They represent ISS concentration, algae concentration, and OSS concentration other than algae, respectively.

[0044] The framework of S300 composite watershed hydrology-hydrodynamics-turbidity integrated model was established

[0045] S310 Construction of suspended matter model in hilly area

[0046] The SWAT model divides the basin into multiple sub-basins through the river network, and then further subdivides them into smaller hydrological response units (HRUs). It simulates the land surface cycle based on the water balance equation and soil loss equation, calculates the suspended matter concentration output by rainfall and surface runoff, and evaluates the changes in water resources and water quality in the basin.

[0047] The SUFI2 algorithm in SWAT-CUP was used to optimize and verify the model parameters, and the runoff and sediment parameters suitable for the specific conditions of the current basin were selected. The accuracy of the model results can be evaluated using the correlation coefficient (R²), Nash coefficient (NS) and percentage bias (PBIAS).

[0048] Construction of suspended matter model in S320 plain polder area

[0049] The Polder Hydrology and Phosphorus Modeling System (PHPS) is a coupled model consisting of the WALRUS-paddy model (a module for simulating runoff and pond water in the polder area), the MUSLE model (a module for simulating the phosphorus cycle in the polder area), and the INCA-P model (a module for simulating the phosphorus cycle in the polder area). It can be used to simulate the water and sediment (suspended matter) production in the polder area. The runoff and sediment production modules of the PHPS model are used to simulate the land surface circulation and calculate the suspended matter concentration output by rainfall and surface runoff.

[0050] The relevant contents of the PHPS model have been disclosed in an article previously published by the inventor of the present application (cited below), and will not be repeated in the present application.

[0051] [1]Yan, R., Huang, J., Li, L., Gao*, J., 2017. Hydrology and phosphorus transport simulation in a lowland polder by a coupled modeling system. Environ. Pollut. 227, 613–625.

[0052] [2]Yan R., Gao* J., Huang, J., 2019. Modeling the hydrological processes of a Chinese lowland polder and identifying the key factors using an improved PHPS model. Journal of Hydrology, 578: 124083.

[0053] Construction of S330 river network hydrodynamics-suspended matter model

[0054] This implementation uses the hydrodynamics module (HD) in the MIKE11 model to simulate the flow and water level of the river, and on this basis, the convection diffusion module (AD) is selected to simulate the transport process of suspended matter in the water body. The construction includes the steps of river network file creation, cross-section file creation, boundary file creation, parameter file creation, simulation file setting, etc. In the AD module, it is necessary to set the suspended matter boundary conditions, diffusion coefficient, pollutant attenuation coefficient, sedimentation rate and resuspension rate. The diffusion coefficient, pollutant attenuation coefficient, sedimentation rate and resuspension rate can be determined based on the properties of the water body itself, based on existing methods, such as literature research, and based on measured data calibration.

[0055] S340 SWAT-PHPS-MIKE11-(Suspended Matter-Turbidity Relationship Model) Coupling

[0056] (1) Coupling between SWAT, PHPS and MIKE11 models

[0057] In the coupling framework, the SWAT and PHPS models simulate the rainfall runoff, soil erosion and other processes in the upstream hilly area and the downstream polder area respectively, and output the land surface water and sediment (suspended solids) production. Then, the land surface water and sediment (suspended solids) production is used as the input boundary conditions of the water volume and suspended solids volume of the MIKE11 river grid in the form of point source at the outlet of the sub-basin. MIKE11 calculates the river network confluence process of water and suspended solids through the hydrodynamic HD and convection-diffusion AD modules, and realizes the simulation of the hydrodynamic transport of materials from the river network to the outlet of the basin (see Figure 1 ).

[0058] In the past, the coupling between models was mostly a one-way input-output relationship. However, unlike the hilly area, the plain polder area is mainly composed of rice fields. The polder area and the river outside the polder area must frequently exchange water to meet the requirements of rice growth irrigation and flood control and drainage in the polder area. Therefore, the coupling between the SWAT model and MIKE11 in the hilly area in this invention is a one-way input-output relationship, while the PHPS model and MIKE11 in the plain polder area will be a two-way coupling, which is mainly reflected in the following process:

[0059] ① The input and replenishment of artificial drainage and sediment (suspended matter) in the polder area to the river outside the polder

[0060] Due to the relative isolation and particularity of the water collection units in the polder area, each polder area will be divided into separate sub-basins, which will be simulated by the PHPS model. The calculation results of the drainage and sediment (suspended matter) discharge of the polder area based on the PHPS model are used as the input upper boundary conditions for the calculation of the water volume and suspended matter concentration of the MIKE11 river channel, and added to the boundary file (.bnd11) to achieve the coupling of the MIKE11 model and the PHPS model. The confluence node is the intersection of the pump station / culvert of the polder area and the river outside the polder (i.e. the outlet of the sub-basin).

[0061] ② Extraction of water and sand (suspended matter) from the river outside the embankment through artificial irrigation in the embankment area

[0062] Due to the dense water network around the polder area, the frequent large-scale irrigation water during the rice growing season is mainly drawn from the river outside the polder, which will reduce the water volume in the river to a certain extent. Therefore, in the coupled model system, the PHPS model including the lower limit of the suitable water depth in the field (h Q,min1 ), upper limit of suitable water depth (h Q , max1 )、Flooding depth(h Q,flood1 ) The intermittent irrigation management module with three controlled water levels simulates the amount and time of irrigation in the polder area. The irrigation water calculation results will be added as a loss item to the MIKE11 model boundary file (.bnd11).

[0063] (1)

[0064] In the formula, Ir1 is the irrigation water volume, h Q1 is the actual field water depth.

[0065] In addition, along with the use of irrigation water, some river sediment will also be transferred from the river to the polder area.

[0066] ③ Coupling of interaction between groundwater in the polder area and rivers outside the polder

[0067] In the integrated framework, a coupling module for groundwater exchange inside and outside the polder based on Darcy's law is proposed:

[0068] (2)

[0069] In the formula, is the exchange rate of the two waters (mm / h); m is the permeability coefficient of the soil in the polder area and the bottom mud of the river outside the polder (mm / h); (m) is the head loss, which is the groundwater level in the polder area Water level of rivers outside the dike difference; is the seepage path length (m), i.e., the distance from the center of the polder area to the river channel; is the hydraulic gradient. At this time, the rivers outside the dike replenish the groundwater inside the dike. is positive; when When the groundwater in the dike seeps and replenishes to the river outside the dike, is negative. The river water level simulated by the MIKE11 model is given by: Provided by the simulation results of the PHPS model. The two water exchange amounts are also used as input or output items of the water balance of the two models, that is, the two water exchange amounts are added as input items (water inflow) or output items (water outflow) to the original water balance control equations of the PHPS model and the MIKE11 model.

[0070] (2) Impact of ship disturbance on suspended matter and model expression

[0071] Ship disturbance is an important factor affecting the transport of suspended matter in navigable rivers, and most previous models have ignored the role of shipping on suspended matter transport. In fact, the impact of ship disturbance on river suspended matter is very complex, involving many factors and the intersection of different disciplines. Considering the research purpose of this project, mathematical statistical methods are used to simply estimate the contribution of shipping to the river in order to better combine the existing models.

[0072] Specifically, the relationship function curve between the daily ship volume automatic monitoring data and the suspended matter concentration monitoring data of the river is fitted. The slope of the curve is used to estimate the suspended matter concentration increased by each ship, and then the daily ship volume is combined to calculate the suspended matter concentration in the river caused by daily shipping. Finally, the increase in suspended matter load in the river caused by shipping is estimated based on the suspended matter concentration and runoff increased by daily shipping, and the same amount of suspended matter load is added as a boundary condition to the MIKE11 river model.

[0073] (3) Coupling of the MIKE11 river suspended matter model and the suspended matter-turbidity relationship model

[0074] Since the suspended matter components in the statistical model have strong seasonal temporal characteristics, the suspended matter-turbidity relationship statistical model may be different in water bodies in different seasons. Therefore, the river MIKE11 suspended matter transport model and the suspended matter-turbidity relationship model will achieve differentiated loose coupling in different seasons.

[0075] Because the MIKE11 river suspended matter model can currently only accurately output the simulation results of river suspended matter content, the suspended matter content simulation values ​​​​are decomposed into inorganic suspended matter ISS concentration, algae concentration, and OSS concentration components of organic suspended particles other than algae according to the component proportions based on the suspended matter content simulation values ​​​​output by MIKE11 and the seasonal average suspended matter component ratios obtained from long-term monitoring (i.e., ISS concentration, algae concentration, and other OSS concentrations in the suspended matter concentration). Components, and then the turbidity is comprehensively calculated in combination with the suspended matter-turbidity relationship model.

[0076] S400 model parameter optimization and verification

[0077] The LH-OAT global sensitivity analysis method can be used to perform sensitivity analysis on the SWAT model and the PHPS model, and 10 runoff and suspended solids sensitivity parameters of each model can be selected as important calibration parameters. The parameters that need to be calibrated for the MIKE11 model are mainly riverbed roughness, diffusion coefficient, and attenuation coefficient. Parameter calibration is carried out in steps: in terms of type, the flow is calibrated first, then the suspended solids; in terms of space, the upstream is calibrated first, then the downstream.

[0078] Several verification points were selected in the watershed. According to the measured suspended matter concentration at the verification points, the applicability of the model was evaluated using evaluation indicators such as correlation coefficient (R²), Nash coefficient (NS) and percentage deviation (PBIAS), and finally a set of optimized parameters suitable for the study area was established.

[0079] Based on the optimized SWAT-PHPS-MIKE11 coupling model established after verification, S500 simulates the suspended matter concentration in the basin, obtains the spatiotemporal distribution of the suspended matter concentration in the basin, and finally uses the suspended matter-turbidity relationship model to obtain the spatiotemporal distribution of turbidity.

Claims

1. A turbidity simulation method for a hilly-plain composite watershed, characterized in that: include: With the concentration of inorganic suspended solids (ISS), algae, and organic suspended particles (OSS) other than algae as independent variables and turbidity as dependent variable, a linear relationship model was established, and the model parameters were calibrated using measured data. The SWAT model was used to simulate the land surface circulation in the upstream hilly area, and the PHPS model was used to simulate the land surface circulation in the downstream polder area, and the land surface water and suspended solids production in the upstream hilly area and the downstream polder area were output respectively; Based on the output of the SWAT model and the PHPS model, the hydrodynamic module and convection-diffusion module of the MIKE11 model are used to simulate the river network confluence of water and suspended matter to obtain the spatiotemporal distribution of suspended matter concentration in the watershed water body. The ratios of inorganic suspended matter ISS concentration, algae concentration, and organic suspended particulate matter OSS concentration other than algae in the measured suspended matter components in the river channel of the basin are obtained, the suspended matter concentration simulated by the MIKE11 model is decomposed according to the ratios of the components, and the linear relationship model of the calibrated model parameters is used to obtain the spatiotemporal distribution of water turbidity.

2. The method according to claim 1, characterized in that The SWAT model divides the basin into multiple sub-basins through the river network for simulation, and the PHPS model divides each polder area into a separate sub-basin for simulation; The land surface water and suspended solids produced by the SWAT model and the PHPS model are used as the input boundary conditions of the water volume and suspended solids of the MIKE11 river grid in the form of point sources at the outlet of the sub-basin, and the MIKE11 model is used to simulate the river network confluence of water and suspended solids.

3. The method according to claim 1, characterized in that It also includes using the PHPS model to simulate the water consumption and time of irrigation in the polder area, obtaining the irrigation water volume, and adding the calculated irrigation water volume as a loss item to the boundary file of the MIKE11 model.

4. The method according to claim 1, characterized in that It also includes considering the interaction between groundwater in the polder area and rivers outside the polder, adding a groundwater exchange coupling module inside and outside the polder in the coupling calculation of the SWAT model and the MIKE11 model, and its control equation is: ； In the formula, is the exchange amount of the two waters; m is the permeability coefficient of the soil in the polder area and the bottom mud of the river outside the polder; is the water level of the river outside the dike, which is obtained by simulating the river water level using the MIKE11 model; is the groundwater level in the polder area, obtained by PHPS model simulation; The two water exchange amounts are used as input items or output items of the water balance control equation of the SWAT model and the MIKE11 model.

5. The method according to claim 1, characterized in that: It also includes obtaining the increase in suspended matter load in the river caused by river navigation and adding the same amount of suspended matter load as a boundary condition to the MIKE11 model.

6. The method according to claim 5, characterized in that The method for obtaining the increase in river suspended matter load caused by river navigation is as follows: Based on the monitoring data of daily river ship volume and suspended solids concentration, a fitting relationship curve between the two is obtained, and the increased suspended solids concentration of each ship is estimated based on the slope of the curve; Combined with the daily river vessel volume data, the concentration of suspended solids in the river channel increased by daily shipping was calculated; The increase in suspended matter load in the river caused by shipping was estimated based on the increased suspended matter concentration and runoff caused by daily shipping.

7. The method according to claim 1, characterized in that The proportion of suspended matter components actually measured in the river channel is the proportion of seasonal average suspended matter components.

8. A computer device comprising a memory, a processor and a computer program stored in the memory, characterized in that: The processor executes the computer program to implement the steps of the method according to any one of claims 1 to 7.

9. A computer-readable storage medium having a computer program / instruction stored thereon, characterized in that: When the computer program / instructions are executed by a processor, the steps of the method described in any one of claims 1 to 7 are implemented.

10. A computer program product comprising a computer program / instructions, characterized in that When the computer program / instructions are executed by a processor, the steps of the method described in any one of claims 1 to 7 are implemented.

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