Flood flow early warning method, controller, storage medium and program product

Abstract

The invention discloses a flood flow early warning method, a controller, a storage medium and a program product, and relates to the field of hydrological monitoring and disaster early warning. By adopting the technical scheme, after an emergency flow meter emits a first frequency modulation continuous wave to the water surface at the current position, the controller receives a first signal reflected by the water surface and analyzes the spectrum characteristic of the first signal; therefore, the stratified flow phenomenon of the water body is effectively identified. After the emergency flow velocity meter emits a second frequency modulation continuous wave to the water surface at the current position, the controller receives a second signal reflected by the water surface, determines the surface flow velocity and the subsurface flow velocity through the first signal, the second signal and a preset flow velocity calculation formula, and calculates the comprehensive flow velocity by combining the water flow layering coefficient; and finally, flow calculation is performed according to the section coefficient and the actually measured water level. According to the multi-level flow velocity measurement and analysis method, the accuracy of flood flow calculation is remarkably improved, when the instantaneous flow exceeds the preset flow threshold value, early warning is given out in time, and important support is provided for flood prevention and flood fighting.

Description

Technical Field

[0001] This application relates to the field of hydrological monitoring and disaster warning, and particularly to a flood flow warning method, a controller, a storage medium, and a program product. Background Art

[0002] With the intensification of global climate change and the frequent occurrence of extreme weather events, flood disasters have shown new characteristics of strong suddenness and fast evolution speed. Accurately predicting the occurrence of floods is of great significance for flood control and fighting, water conservancy project scheduling, and urban flood control and disaster reduction. Therefore, establishing an accurate and reliable flood prediction system has become a key research topic in the current hydrological field.

[0003] Currently, the commonly used flood prediction methods mainly involve setting up hydrological monitoring stations upstream of the river, regularly collecting water level data and rainfall data, analyzing and processing them, and then combining meteorological forecast information to predict the flood situation in the future for a period of time.

[0004] However, due to the limited distribution of hydrological monitoring stations, it is difficult to cover all areas that may be affected by floods, especially in some remote or inaccessible areas, resulting in often less than ideal prediction accuracy for floods. Summary of the Invention

[0005] This application provides a flood flow warning method, a controller, a storage medium, and a program product for improving the accuracy of flood warning.

[0006] In a first aspect, this application provides a flood flow warning method applied to a controller. The method includes: controlling an emergency current meter to emit a first frequency-modulated continuous wave towards the water surface at the current position and receiving a first signal reflected by the water surface; when a double-peak feature appears in the spectral characteristics of the first signal, controlling the emergency current meter to emit a second frequency-modulated continuous wave towards the water surface at the current position and receiving a second signal reflected by the water surface. The double-peak feature is used to characterize the phenomenon of stratified flow of the water body, and the frequency interval between the second frequency-modulated continuous wave and the first frequency-modulated continuous wave is greater than a preset frequency threshold; determining the surface velocity and the subsurface velocity according to the first signal, the second signal, and a preset velocity calculation formula; calculating a flow stratification coefficient based on the surface velocity and the subsurface velocity to determine the comprehensive velocity; extracting from a preset cross-section coefficient database the cross-section coefficient that best matches the flow state characteristics corresponding to the flow stratification coefficient; substituting the comprehensive velocity, the cross-section coefficient, and the measured water level collected by the emergency current meter into a preset flow calculation formula to obtain the instantaneous flow of the target cross-section; and issuing a warning when the instantaneous flow is greater than a preset flow threshold.

[0007] By adopting the above technical solution, after the emergency current meter emits the first frequency-modulated continuous wave towards the water surface at the current position, the controller receives the first signal reflected by the water surface and analyzes the spectral characteristics of the first signal, thereby effectively identifying the layered flow phenomenon of the water body. After the emergency current meter emits the second frequency-modulated continuous wave towards the water surface at the current position, the controller receives the second signal reflected by the water surface, and determines the surface flow velocity and the subsurface flow velocity through the first signal, the second signal and the preset flow velocity calculation formula, then calculates the comprehensive flow velocity in combination with the water flow stratification coefficient, and finally performs the flow rate calculation in cooperation with the cross-section coefficient and the measured water level. This multi-level flow velocity measurement and analysis method significantly improves the accuracy of flood flow rate calculation, issues a warning in a timely manner when the instantaneous flow rate exceeds the preset flow rate threshold, and provides important support for flood control and flood fighting.

[0008] Combined with some embodiments of the first aspect, in some embodiments, before the step of controlling the emergency current meter to emit the second frequency-modulated continuous wave towards the water surface at the current position and receiving the second signal reflected by the water surface when the spectral characteristics of the first signal present a double-peak characteristic, the method further includes: performing a frequency-domain transformation on the first signal to obtain first spectral data; extracting peak points in the first spectral data whose amplitudes are greater than a preset amplitude threshold; if it is detected that there are two peak points, calculating the frequency difference and amplitude ratio between the two peak points; when the frequency difference is greater than a preset frequency difference threshold and the amplitude ratio is within a preset ratio range, calculating the wave trough depth coefficient between the two peak points; and judging whether the spectral characteristics of the first signal present a double-peak characteristic according to the wave trough depth coefficient.

[0009] By adopting the above technical solution, based on the multi-dimensional spectral characteristic analysis method, the controller can accurately identify the layered flow phenomenon of the water body, effectively avoid misjudgment, lay a reliable foundation for subsequent layered flow velocity measurement, and significantly improve the reliability of water flow characteristic identification.

[0010] Combined with some embodiments of the first aspect, in some embodiments, determining the surface flow velocity and the subsurface flow velocity according to the first signal, the second signal and the preset flow velocity calculation formula specifically includes: respectively extracting the surface reflection peak frequency and the subsurface reflection peak frequency according to the spectral characteristics of the first signal and the spectral characteristics of the second signal; substituting the surface reflection peak frequency and the transmission frequency of the first frequency-modulated continuous wave into the preset flow velocity calculation formula to obtain the surface flow velocity; substituting the subsurface reflection peak frequency and the transmission frequency of the second frequency-modulated continuous wave into the preset flow velocity calculation formula to obtain the subsurface flow velocity; the preset flow velocity calculation formula is: ; where V represents the flow velocity, f represents the reflection peak frequency, ft represents the transmission frequency, c represents the propagation speed of electromagnetic waves in the medium, and θ represents the angle between the frequency-modulated continuous wave and the flow rate.

[0011] By adopting the above technical solution, the controller analyzes the spectral characteristics of the first signal and the second signal respectively, extracts the surface reflection peak frequency and the subsurface reflection peak frequency, and then combines the transmission frequencies corresponding to the first frequency-modulated continuous wave and the second frequency-modulated continuous wave. Based on the Doppler effect principle, a complete preset flow velocity calculation formula is established. This preset flow velocity calculation formula takes into account key factors such as the propagation speed of electromagnetic waves in the medium and the incident angle, making the flow velocity calculation more accurate. This layered flow velocity measurement method can not only accurately obtain the flow velocity information of different water layers, but also ensure the consistency and comparability of the results through a unified preset flow velocity calculation formula, providing reliable data support for the subsequent determination of the comprehensive flow velocity.

[0012] Combined with some embodiments of the first aspect, in some embodiments, based on the surface flow velocity and the subsurface flow velocity, the water flow stratification coefficient is calculated, specifically including: extracting the first energy value of the surface reflection peak in the first signal spectrum and the second energy value of the subsurface reflection peak in the second signal spectrum; dividing the first energy value by the sum of the first energy value and the second energy value to obtain the surface energy proportion; when the surface energy proportion is greater than the preset first energy threshold, setting the water flow stratification coefficient to 1; when the surface energy proportion is less than the preset second energy threshold, setting the water flow stratification coefficient to 0; when the surface energy proportion is between the first energy threshold and the second energy threshold, setting the water flow stratification coefficient equal to the surface energy proportion.

[0013] By adopting the above technical solution, first, the controller extracts the first energy value of the surface reflection peak in the first signal spectrum and the second energy value of the subsurface reflection peak in the second signal spectrum, and calculates the surface energy proportion, which can accurately reflect the flow states of each layer of the water body. Then, the controller determines the water flow stratification coefficient in the form of a piecewise function, that is, taking 1 when the surface energy proportion exceeds the preset first energy threshold, taking 0 when it is less than the preset second energy threshold, and taking the actual proportion value when it is between the two. This processing method not only retains the continuous change characteristics but also avoids the interference of extreme cases. Finally, the controller converts the complex water flow stratification phenomenon into a quantitative water flow stratification coefficient, providing a reliable basis for the subsequent comprehensive calculation of the flow velocity and significantly improving the accuracy of the flow rate calculation.

[0014] Combined with some embodiments of the first aspect, in some embodiments, the water flow stratification coefficient is calculated to determine the comprehensive flow velocity, specifically including: if the water flow stratification coefficient is greater than the preset first threshold, taking the surface flow velocity as the comprehensive flow velocity; if the water flow stratification coefficient is less than the preset second threshold, taking the subsurface flow velocity as the comprehensive flow velocity; if the water flow stratification coefficient is between the preset first threshold and the preset second threshold, performing a weighted sum of the surface flow velocity and the subsurface flow velocity to obtain the comprehensive flow velocity.

[0015] By adopting the above technical solution, the controller sets a preset first threshold and a preset second threshold, divides the water flow stratification coefficient into three intervals, and adopts different flow velocity calculation strategies respectively: when the water flow stratification coefficient is large, the surface flow velocity is directly adopted; when it is small, the subsurface flow velocity is adopted; and when it is between the preset first threshold and the preset second threshold, weighted calculation is carried out. This segmented processing method not only takes into account the complexity of water flow stratification but also avoids the errors that may be brought by simple averaging, making the calculation of the comprehensive flow velocity more in line with the actual hydrological characteristics, thereby improving the reliability of flow warning.

[0016] Combined with some embodiments of the first aspect, in some embodiments, the preset flow calculation formula is: Q = K × VC × A × (1 + α × H / Href); where Q represents the instantaneous flow of the target cross-section, K represents the cross-section coefficient, VC represents the comprehensive flow velocity, A represents the cross-sectional area of the water passage, α represents the water level correction coefficient, H represents the measured water level, and Href represents the reference water level.

[0017] By adopting the above technical solution, the preset flow calculation formula not only retains the advantages of the traditional flow calculation method but also adds the influencing factor of water level change, making the calculation result more accurate. Especially in the case of drastic water level changes during floods, the preset flow calculation formula can better reflect the actual changes in flood flow, providing a reliable basis for timely warning.

[0018] Combined with some embodiments of the first aspect, in some embodiments, after the step of issuing a warning when the instantaneous flow is greater than the preset flow threshold, the method further includes: obtaining the historical water level data of the target cross-section; extracting water level change characteristic parameters based on the historical water level data, and the water level change characteristic parameters include the water level rising rate, the water level duration, and the maximum water level value; extracting flow change characteristic parameters based on the instantaneous flow, and the flow change characteristic parameters include the flow peak value, the flow rising rate, and the flood peak duration; performing flood characteristic analysis on the water level change characteristic parameters and the flow change characteristic parameters to determine the flood type of the target cross-section.

[0019] By adopting the above technical solution, the controller analyzes the water level change characteristic parameters and the flow change characteristic parameters, and can comprehensively master the flood evolution trend. This multi-dimensional characteristic analysis method can not only timely detect the flood threat but also judge the flood type, providing a more targeted basis for flood control decision-making. At the same time, by analyzing historical data to establish a reference benchmark, the accuracy of flood type judgment is improved, making the flood warning more accurate.

[0020] Second aspect, embodiments of the present application provide a controller, which includes: one or more processors and a memory; the memory is coupled to the one or more processors, and the memory is used to store computer program code, the computer program code includes computer instructions, and the one or more processors call the computer instructions to cause the controller to execute the method described in the first aspect and any possible implementation manner in the first aspect.

[0021] Third aspect, embodiments of the present application provide a computer program product containing instructions. When the computer program product runs on a controller, it causes the controller to execute the method described in the first aspect and any possible implementation manner in the first aspect.

[0022] Fourth aspect, embodiments of the present application provide a computer-readable storage medium, including instructions. When the instructions run on a controller, it causes the controller to execute the method described in the first aspect and any possible implementation manner in the first aspect.

[0023] It can be understood that the controller provided in the second aspect above, the computer program product provided in the third aspect, and the computer storage medium provided in the fourth aspect are all used to execute the method provided in the embodiments of the present application. Therefore, the beneficial effects that can be achieved can refer to the beneficial effects in the corresponding method, which will not be elaborated here.

[0024] One or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages: 1. By adopting the above technical solution, after the emergency current meter emits a first frequency-modulated continuous wave to the water surface at the current position, the controller receives the first signal reflected by the water surface and analyzes the spectral characteristics of the first signal, so as to effectively identify the stratified flow phenomenon of the water body. After the emergency current meter emits a second frequency-modulated continuous wave to the water surface at the current position, the controller receives the second signal reflected by the water surface, and determines the surface flow velocity and the subsurface flow velocity through the first signal, the second signal and a preset flow velocity calculation formula, then calculates the comprehensive flow velocity in combination with the water flow stratification coefficient, and finally calculates the flow rate in cooperation with the cross-section coefficient and the measured water level. This multi-level flow velocity measurement and analysis method significantly improves the accuracy of flood flow rate calculation, issues an early warning in time when the instantaneous flow rate exceeds the preset flow rate threshold, and provides important support for flood control and disaster relief.

[0025] 2. By adopting the above technical solution, first, the controller obtains the first energy value of the surface reflection peak in the first signal spectrum and the second energy value of the subsurface reflection peak in the second signal spectrum, and calculates the surface energy ratio, which can accurately reflect the flow state of each layer of water body. Then, the controller determines the water flow stratification coefficient in the form of a piecewise function, that is, when the surface energy ratio exceeds the preset first energy threshold, it takes 1; when it is less than the preset second energy threshold, it takes 0; when it is between the two, it takes the actual ratio value. This processing method not only retains the continuous change characteristics but also avoids the interference of extreme situations. Finally, the controller converts the complex water flow stratification phenomenon into a quantitative water flow stratification coefficient, providing a reliable basis for the subsequent comprehensive calculation of flow velocity and significantly improving the accuracy of flow calculation.

[0026] 3. By adopting the above technical solution, the controller sets the preset first threshold and the preset second threshold, divides the water flow stratification coefficient into three intervals, and adopts different flow velocity calculation strategies respectively: when the water flow stratification coefficient is large, directly adopt the surface flow velocity; when it is small, adopt the subsurface flow velocity; when it is between the preset first threshold and the preset second threshold, perform weighted calculation. This piecewise processing method not only considers the complexity of water flow stratification but also avoids the errors that may be brought by simple averaging, making the calculation of the comprehensive flow velocity more in line with the actual hydrological characteristics, thereby improving the reliability of flood flow warning. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is a flowchart of a flood flow warning method in an embodiment of the present application; Figure 2 is another flowchart of a flood flow warning method in an embodiment of the present application; Figure 3 is a schematic structural diagram of an entity device of a controller in an embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0028] The terms used in the following embodiments of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application. As used in the specification of the present application, the singular forms "a", "an", "the above", "the", and "this" are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used in the present application refers to any or all possible combinations including one or more of the listed items.

[0029] Hereinafter, the terms "first" and "second" are only used for descriptive purposes and should not be construed as implying or suggesting relative importance or implicitly indicating the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the embodiments of the present application, unless otherwise specified, the meaning of "a plurality" is two or more.

[0030] The following describes the process of the method provided in this embodiment in combination with the above scenario. Please refer to Figure 1 , which is a schematic flowchart of a flood flow warning method in an embodiment of the present application.

[0031] S101. Control the emergency current meter to emit a first frequency-modulated continuous wave at the current position towards the water surface and receive the first signal reflected by the water surface; Wherein, the controller refers to an electronic device used to implement flood flow warning; the emergency current meter refers to a portable instrument device used to measure the water flow velocity; the current position refers to the measurement point position where the emergency current meter is located; the frequency-modulated continuous wave refers to an electromagnetic wave signal whose frequency changes continuously over time; the water surface refers to the surface of the river or water area to be measured; the first frequency-modulated continuous wave is used to represent the initial detection signal emitted by the controller controlling the emergency current meter; the first signal refers to the first frequency-modulated continuous wave signal reflected by the water surface.

[0032] When water flow velocity information needs to be obtained, the controller executes this step. Specifically, first, the controller determines the installation position of the emergency current meter so that it can be correctly aligned with the water surface. Then, the controller generates a first frequency-modulated continuous wave through the signal generator of the emergency current meter, and the frequency range and modulation parameters of the first frequency-modulated continuous wave are preset according to actual measurement requirements. The controller controls the emergency current meter to emit the first frequency-modulated continuous wave at the current position towards the water surface. When the first frequency-modulated continuous wave encounters the water surface, it is reflected, and the controller collects the first signal reflected by the water surface through the receiving module of the emergency current meter.

[0033] S102. When the spectral feature of the first signal shows a double-peak feature, control the emergency current meter to emit a second frequency-modulated continuous wave at the current position towards the water surface and receive the second signal reflected by the water surface. The double-peak feature is used to characterize the phenomenon of stratified flow of the water body, and the frequency interval between the second frequency-modulated continuous wave and the first frequency-modulated continuous wave is greater than the preset frequency threshold; Wherein, the spectral feature refers to the distribution characteristic of the signal in the frequency domain; the double-peak feature refers to the appearance of two obvious peaks in the spectrum; the stratified flow phenomenon indicates the phenomenon that there are different flow velocity layers in the vertical direction of the water body; the frequency interval refers to the difference between the frequencies of two signals; the preset frequency threshold refers to the preset minimum frequency interval standard; the second frequency-modulated continuous wave is used to represent the second detection signal emitted by the controller controlling the emergency current meter; the second signal refers to the second frequency-modulated continuous wave signal reflected by the water surface.

[0034] When the spectral characteristics of the first signal exhibit a bimodal feature, the controller executes this step. Specifically, first, the controller performs spectral analysis on the first signal to obtain its spectral characteristics through methods such as Fourier transform. When it is found that there are two significant peaks in the spectral characteristics and the frequency difference and amplitude ratio between the peaks meet the preset conditions, the controller determines it as a bimodal feature, indicating that there may be stratified flow in the water body. At this time, the controller generates a new frequency-modulated continuous wave as the second frequency-modulated continuous wave, whose frequency needs to maintain a sufficient interval (greater than the preset frequency threshold) from the frequency of the first frequency-modulated continuous wave to be able to detect different water layers separately. The controller then controls the emergency current meter to transmit this second frequency-modulated continuous wave and receive the second signal reflected from the water surface.

[0035] S103. Determine the surface velocity and subsurface velocity according to the first signal, the second signal, and the preset velocity calculation formula; Among them, the preset velocity calculation formula is a mathematical expression for converting signal characteristics into water flow velocity; the surface velocity refers to the flow velocity of the water surface layer; the subsurface velocity refers to the flow velocity at a certain depth below the water surface.

[0036] After obtaining the first signal and the second signal, the controller executes this step. Specifically, first, the controller performs spectral analysis on the first signal and the second signal respectively, extracts the surface reflection peak frequency from the first signal, and extracts the subsurface reflection peak frequency from the second signal. Then, the controller according to the preset velocity calculation formula: , calculates the surface velocity and the subsurface velocity respectively. Among them, V represents the velocity, f represents the reflection peak frequency, ft represents the transmission frequency, c represents the propagation speed of electromagnetic waves in the medium, and θ represents the angle between the propagation direction of the frequency-modulated continuous wave and the water flow direction. The controller can convert the frequency difference into the actual velocity value through the preset velocity calculation formula, so as to obtain the velocity information of different layers of the water body.

[0037] Optionally, generally, determining the surface velocity and the subsurface velocity according to the first signal, the second signal, and the preset velocity calculation formula can be achieved in the following ways, which are not limited here: Extract the surface reflection peak frequency and the subsurface reflection peak frequency according to the spectral characteristics of the first signal and the spectral characteristics of the second signal respectively; Substitute the surface reflection peak frequency and the transmission frequency of the first frequency-modulated continuous wave into the preset velocity calculation formula to obtain the surface velocity; Substitute the subsurface reflection peak frequency and the transmission frequency of the second frequency-modulated continuous wave into the preset velocity calculation formula to obtain the subsurface velocity.

[0038] The following lists a specific example: The transmission frequency of the first frequency-modulated continuous wave: ft1 = 24 GHz; Surface reflection peak frequency extracted from the first signal: f1 = 24.000160 GHz; Transmission frequency of the second frequency-modulated continuous wave: ft2 = 25 GHz; Subsurface reflection peak frequency extracted from the second signal: f2 = 25.000170 GHz; Apply the preset flow velocity calculation formula: ; Assume c (propagation speed of electromagnetic waves in water) = 3×10 8 m / s, θ (angle between the propagation direction of the frequency-modulated continuous wave and the water flow direction) = 60°; Calculate the flow velocity respectively: V surface flow velocity = (160×3×10 8 ) / (2×24×10 9 ×cos60°) = 2.0 m / s; V subsurface flow velocity = (170×3×10 8 ) / (2×25×10 9 ×cos60°) = 2.04 m / s.

[0039] S104. Calculate the water flow stratification coefficient based on the surface flow velocity and the subsurface flow velocity to determine the comprehensive flow velocity; Among them, the water flow stratification coefficient is a dimensionless parameter used to quantify the degree of water flow stratification; the comprehensive flow velocity refers to the overall flow velocity considering the influence of stratification.

[0040] After obtaining the surface flow velocity and the subsurface flow velocity, the controller executes this step. Specifically, first, extract the first energy value of the surface reflection peak in the first signal spectrum and the second energy value of the subsurface reflection peak in the second signal spectrum. The controller calculates the ratio of the first energy value to the total energy value (the sum of the first energy value and the second energy value) to obtain the surface energy ratio. According to the magnitude of this surface energy ratio, the controller uses a piecewise function to determine the water flow stratification coefficient: when the surface energy ratio is greater than the preset first energy threshold (such as 0.8), take 1, indicating that the surface flow is dominant; when the surface energy ratio is less than the preset second energy threshold (such as 0.2), take 0, indicating that the subsurface flow is dominant; when the surface energy ratio is between the preset first energy threshold and the preset second energy threshold, directly use the surface ratio as the water flow stratification coefficient. Subsequently, the controller determines the comprehensive flow velocity according to the water flow stratification coefficient: when the water flow stratification coefficient is close to 1, use the surface flow velocity, when it is close to 0, use the subsurface flow velocity, and in the intermediate region, perform a weighted average of the two flow velocities according to the water flow stratification coefficient to obtain the comprehensive flow velocity.

[0041] Optionally, generally, based on the surface flow velocity and the subsurface flow velocity, calculating the water flow stratification coefficient can be achieved in the following ways, which are not limited herein: extract the first energy value of the surface reflection peak in the first signal spectrum and the second energy value of the subsurface reflection peak in the second signal spectrum; divide the first energy value by the sum of the first energy value and the second energy value to obtain the surface energy proportion; when the surface energy proportion is greater than the preset first energy threshold, set the water flow stratification coefficient to 1; when the surface energy proportion is less than the preset second energy threshold, set the water flow stratification coefficient to 0; when the surface energy proportion is between the first energy threshold and the second energy threshold, set the water flow stratification coefficient equal to the surface energy proportion.

[0042] Wherein, the energy value refers to the energy magnitude corresponding to the peak in the signal spectrum; the preset first energy threshold refers to the energy proportion threshold for determining complete surface flow; the preset second energy threshold refers to the energy proportion threshold for determining complete subsurface flow; weighted summation means performing an addition operation on multiple flow velocity values according to different weights.

[0043] Optionally, generally, calculating the water flow stratification coefficient to determine the comprehensive flow velocity can be achieved in the following ways, which are not limited herein: if the water flow stratification coefficient is greater than the preset first threshold, use the surface flow velocity as the comprehensive flow velocity; if the water flow stratification coefficient is less than the preset second threshold, use the subsurface flow velocity as the comprehensive flow velocity; if the water flow stratification coefficient is between the preset first threshold and the preset second threshold, perform a weighted summation on the surface flow velocity and the subsurface flow velocity to obtain the comprehensive flow velocity.

[0044] S105. Extract the cross-section coefficient that best matches the flow regime characteristics corresponding to the water flow stratification coefficient from the preset cross-section coefficient database; Wherein, the cross-section coefficient database is used to represent a data set storing cross-section coefficients under different flow regimes; the cross-section coefficient is a hydraulic parameter used to correct the flow rate calculation.

[0045] After determining the water flow stratification coefficient and the comprehensive flow velocity, the controller executes this step. Specifically, first, the controller accesses the preset cross-section coefficient database, which stores cross-section coefficients and their corresponding flow regime characteristic parameters under different water flow conditions. The controller compares the currently obtained characteristic parameters such as the water flow stratification coefficient and the comprehensive flow velocity with the reference data in the preset cross-section coefficient database, and calculates the matching degree score. By searching for the record with the highest matching degree, the controller extracts the corresponding cross-section coefficient. This can select the most suitable cross-section coefficient according to the actual water flow state and improve the accuracy of subsequent flow rate calculations.

[0046] S106. Substitute the comprehensive flow velocity, the cross-section coefficient, and the measured water level collected by the emergency flow velocity meter into the preset flow rate calculation formula to obtain the instantaneous flow rate of the target cross-section; Among them, the preset flow calculation formula refers to the mathematical expression used to calculate the cross-sectional flow, and the preset flow calculation formula is: Q = K × VC × A × (1 + α × H / Href), where Q represents the instantaneous flow of the target cross-section, K represents the cross-section coefficient, VC represents the comprehensive flow velocity, A represents the cross-sectional area of the water flow, α represents the water level correction coefficient, H represents the measured water level, and Href represents the reference water level; the measured water level refers to the current water level value measured by the emergency current meter; the cross-sectional area of the water flow represents the effective cross-sectional area through which the water flow passes; the water level correction coefficient refers to the parameter used to correct the influence of the water level; the reference water level represents the water level value under the standard state; the instantaneous flow is used to represent the magnitude of the water flow at a certain moment.

[0047] After obtaining each calculation parameter, the controller executes this step. Specifically, the controller calculates using the preset flow calculation formula, and the controller substitutes the required parameters to obtain the instantaneous flow of the target cross-section at the current moment.

[0048] S107. When the instantaneous flow is greater than the preset flow threshold, issue a warning.

[0049] Among them, the preset flow threshold refers to the flow critical value for triggering a flood warning; the warning refers to the warning prompt information.

[0050] After calculating the instantaneous flow, the controller executes this step. Specifically, the controller compares the calculated instantaneous flow with the preset flow threshold. When the instantaneous flow exceeds the preset flow threshold, the controller determines the warning level according to the degree of overrun, which can be divided into multiple levels such as general warning, important warning, and emergency warning. Then the controller selects the corresponding warning method according to the warning level, such as on-site sound and light alarm, sending warning information to the monitoring center, pushing warning text messages to the flood control department, etc. At the same time, the controller will also record key data such as the flow and water level at the warning moment for subsequent analysis and processing. Through timely and accurate warnings, important decision-making support can be provided for flood control and fighting.

[0051] By adopting the above technical solution, after the emergency current meter emits the first frequency-modulated continuous wave to the water surface at the current position, the controller receives the first signal reflected by the water surface and analyzes the spectral characteristics of the first signal, so as to effectively identify the layered flow phenomenon of the water body. After the emergency current meter emits the second frequency-modulated continuous wave to the water surface at the current position, the controller receives the second signal reflected by the water surface, and determines the surface flow velocity and the subsurface flow velocity through the first signal, the second signal and the preset flow velocity calculation formula, then calculates the comprehensive flow velocity in combination with the flow stratification coefficient, and finally performs flow calculation in cooperation with the cross-section coefficient and the measured water level. This multi-level flow velocity measurement and analysis method significantly improves the accuracy of flood flow calculation, issues a warning in a timely manner when the instantaneous flow exceeds the preset flow threshold, and provides important support for flood control and fighting.

[0052] The following is a further and more specific process description of the method provided in this embodiment. Please refer to Figure 2 , which is another process schematic diagram of the flood flow warning method in the embodiment of the present application.

[0053] S201. Control the emergency flow velocity meter to emit a first frequency-modulated continuous wave towards the water surface at the current position and receive the first signal reflected by the water surface; Specifically, refer to step S101, which will not be elaborated here.

[0054] S202. Perform a frequency-domain transformation on the first signal to obtain first spectral data; Among them, the frequency-domain transformation refers to a mathematical operation method for converting a signal from the time domain to the frequency domain; the first spectral data refers to the frequency-amplitude data obtained after the first signal undergoes a frequency-domain transformation.

[0055] After obtaining the original data of the first signal, the controller executes this step. Specifically, first, the controller preprocesses the first signal, including removing the DC component, filtering out high-frequency noise, etc. Then, the controller selects a suitable window function (such as a Hamming window) to window the first signal to reduce spectral leakage. Next, the controller uses the fast Fourier transform (FFT) algorithm to perform a frequency-domain transformation on the processed first signal to obtain a complex spectrum. Finally, the controller converts the complex spectrum into an amplitude spectrum to obtain the first spectral data representing the relationship between frequency and the corresponding amplitude. The controller adjusts the sampling parameters and transformation length to ensure sufficient frequency resolution for subsequent feature extraction.

[0056] S203. Extract the peak points in the first spectral data whose amplitudes are greater than the preset amplitude threshold; Among them, the preset amplitude threshold refers to the minimum amplitude standard for screening effective peaks; the peak point refers to the local maximum point in the spectrum.

[0057] After obtaining the first spectral data, the controller executes this step. Specifically, first, the controller determines the noise floor level of the first spectral data and sets the preset amplitude threshold to several times (usually 3-5 times) the noise floor. The noise floor represents the background noise level in the spectrum. Then, the controller uses a peak detection algorithm to scan the entire spectrum to find local maximum points. The peak detection algorithm refers to a calculation method for finding local maxima. For each candidate peak point, the controller calculates its significance index, including the amplitude difference from neighboring points, the sharpness of the peak, etc. Only the peak points whose amplitudes exceed the preset amplitude threshold and whose significance meets the requirements are retained. At the same time, the controller also records the characteristic parameters such as the frequency position, amplitude size, and effective bandwidth of each effective peak point.

[0058] S204. If two peak points are detected, calculate the frequency difference and amplitude ratio between the two peak points; Among them, the frequency difference represents the frequency interval between two peak points; the amplitude ratio refers to the proportional relationship between the amplitudes of two peak points.

[0059] When two peak points are detected, the controller executes this step. Specifically, first, the controller sorts the two peak points according to the amplitude size to determine the main peak and the secondary peak. The main peak represents the peak with a larger amplitude, and the secondary peak represents the peak with a smaller amplitude. Then, the controller calculates the difference in the frequency positions of the two peak points to obtain the frequency difference. At the same time, the controller calculates the ratio of the amplitude of the secondary peak to the amplitude of the main peak to obtain the amplitude ratio. The controller will also analyze other characteristics of the two peaks, such as the shape symmetry of the peaks and the relative distribution of the frequency positions, to assist in judging the validity of the peaks. These characteristic parameters will be used for subsequent double-peak characteristic judgment.

[0060] S205. When the frequency difference is greater than the preset frequency difference threshold and the amplitude ratio is within the preset ratio range, calculate the valley depth coefficient between the two peak points; Among them, the preset frequency difference threshold is the minimum frequency difference standard for judging the separation degree of the two peaks; the preset ratio range refers to the effective value range of the amplitude ratio; the valley depth coefficient represents the relative depth of the valley between the two peaks.

[0061] After obtaining the frequency difference and the amplitude ratio, the controller executes this step. Specifically, first, the controller compares the calculated frequency difference with the preset frequency difference threshold, and the preset frequency difference threshold is usually determined according to the signal bandwidth and measurement accuracy requirements. At the same time, the controller checks whether the amplitude ratio falls within the preset ratio range, and this preset ratio range is usually determined based on experimental data and theoretical analysis. When both conditions are met, the controller searches for the lowest point between the two peak points as the valley position, and then calculates the valley depth coefficient. The specific method is to divide the difference between the amplitude of the valley point and the arithmetic mean of the amplitudes of the two peaks by the arithmetic mean of the amplitudes of the two peaks to obtain a normalized relative depth value.

[0062] S206. Judge whether the spectrum characteristics of the first signal present double-peak characteristics according to the valley depth coefficient; After calculating the valley depth coefficient, the controller executes this step. Specifically, first, the controller compares the valley depth coefficient with the preset depth threshold, and the preset depth threshold is usually set between 0.3 and 0.5. The controller comprehensively considers all the characteristic parameters obtained previously, including the frequency difference, the amplitude ratio, the valley depth coefficient, etc., and establishes a comprehensive judgment model. This comprehensive judgment model can adopt methods such as weighted scoring or fuzzy logic to comprehensively evaluate each characteristic parameter and obtain a characteristic credibility score. When the characteristic credibility score exceeds the preset threshold, it is determined that the spectrum characteristics of the first signal present double-peak characteristics.

[0063] S207. When the spectral feature of the first signal shows a bimodal feature, control the emergency current meter to emit a second frequency-modulated continuous wave towards the water surface at the current position, and receive the second signal reflected by the water surface. The bimodal feature is used to characterize the phenomenon of stratified flow in the water body. The frequency interval between the second frequency-modulated continuous wave and the first frequency-modulated continuous wave is greater than a preset frequency threshold; Specifically, refer to step S102, which will not be elaborated here.

[0064] S208. Determine the surface flow velocity and the subsurface flow velocity according to the first signal, the second signal, and a preset flow velocity calculation formula; Specifically, refer to step S103, which will not be elaborated here.

[0065] S209. Calculate the flow stratification coefficient based on the surface flow velocity and the subsurface flow velocity to determine the comprehensive flow velocity; Specifically, refer to step S104, which will not be elaborated here.

[0066] S210. Extract the cross-section coefficient that best matches the flow regime characteristics corresponding to the flow stratification coefficient from a preset cross-section coefficient database; Specifically, refer to step S105, which will not be elaborated here.

[0067] S211. Substitute the comprehensive flow velocity, the cross-section coefficient, and the measured water level collected by the emergency current meter into a preset flow rate calculation formula to obtain the instantaneous flow rate of the target cross-section; Specifically, refer to step S106, which will not be elaborated here.

[0068] S212. Issue a warning when the instantaneous flow rate is greater than a preset flow rate threshold; Specifically, refer to step S107, which will not be elaborated here.

[0069] S213. Obtain the historical water level data of the target cross-section; Among them, the target cross-section refers to a specific river cross-section position for flood monitoring; the historical water level data refers to the water level measurement values recorded at this target cross-section over a past period of time.

[0070] After issuing a flood warning, the controller executes this step. Specifically, first, the controller accesses the hydrological database and extracts the water level observation data of the target cross-section in the recent period (such as the recent 24 hours). For the obtained historical water level data, the controller performs data quality checks, including removing outliers, filling in missing values, smoothing noise, etc. At the same time, the controller also obtains the water level observation data for a longer period (such as the recent 7 days) as a reference for establishing the background trend of water level changes. All processed data is sorted into a standardized time series in chronological order and necessary time markings and data annotations are made for subsequent analysis.

[0071] S214. Extract water level change characteristic parameters based on historical water level data. The water level change characteristic parameters include the water level rising rate, the water level duration, and the maximum water level value. Among them, the water level rising rate refers to the increment of the water level per unit time; the water level duration refers to the continuous period during which the water level exceeds a specific value; the maximum water level value refers to the highest water level record during the observation period.

[0072] After obtaining the processed historical water level data, the controller executes this step. Specifically, the controller uses the sliding window method to calculate the water level rising rates at different time scales, including the average change rates of multiple time windows such as 10 minutes, 30 minutes, and 1 hour. By analyzing the fluctuation characteristics of the water level sequence, the controller identifies important inflection points (an inflection point indicates the moment when the water level change rate changes significantly), divides the entire process into multiple stages, and calculates the duration of each stage. At the same time, the controller extracts the maximum water level value during the entire observation period and records the moment when it appears. The controller also calculates statistical indicators of various characteristic parameters, such as the average rising rate, the maximum rising rate, the cumulative time of the water level exceeding the warning level, etc., to form a complete set of water level change characteristic parameters.

[0073] S215. Extract flow change characteristic parameters based on instantaneous flow. The flow change characteristic parameters include the flow peak value, the flow rising rate, and the flood peak duration. Among them, the flow peak value refers to the maximum flow value during the observation period; the flow rising rate refers to the increment of the flow per unit time; the flood peak duration refers to the continuous time during which the flow maintains a high value range.

[0074] After obtaining the instantaneous flow, the controller executes this step. Specifically, first, the controller combines the currently obtained instantaneous flow with the historical flow data to construct a complete flow hydrograph. A flow hydrograph refers to a curve of the flow changing with time. By analyzing the flow hydrograph, the controller extracts the flow peak value and the moment when it appears, and calculates the flow rising rates at different time scales (such as 1 hour, 3 hours, 6 hours). The controller sets multiple flow thresholds, counts the duration of the flow exceeding each level of flow threshold, and determines the flood peak duration. At the same time, the controller analyzes the rising and falling processes of the flow, calculates the average change rates of the rising and falling segments, and identifies key change nodes. All the extracted characteristic parameters will be normalized and saved for subsequent flood characteristic analysis.

[0075] S216. Conduct flood characteristic analysis on the water level change characteristic parameters and the flow change characteristic parameters to determine the flood type of the target section.

[0076] Among them, flood characteristic analysis refers to the comprehensive study of the water level change characteristic parameters and the flow change characteristic parameters; flood type refers to the types of flood processes classified based on characteristic parameters.

[0077] After obtaining all the characteristic parameters, the controller executes this step. Specifically, first, the controller establishes a multi-dimensional analysis model of the characteristic parameters and standardizes the water level change characteristic parameters and the flow rate change characteristic parameters. Then, the controller performs pattern matching with the pre-established flood type characteristic library and calculates the similarity with each type of standard pattern. The similarity calculation considers multiple aspects, including the matching degree of parameters such as peak size, rising rate, and duration. Based on the similarity analysis result, the controller determines the most likely type of the current flood process, such as mountain flood type, plain type, mixed type, etc. At the same time, the controller evaluates its danger level and possible evolution trend, providing a basis for flood control and flood fighting decisions.

[0078] The controller in the embodiment of the present invention application will be described from the perspective of hardware processing. Please refer to Figure 3 , which is a schematic structural diagram of an entity device of the controller in the embodiment of the present application.

[0079] It should be noted that Figure 3 the structure of the controller shown is only an example and should not bring any limitations to the functions and usage scopes of the embodiments of the present invention.

[0080] As Figure 3 shown, the controller includes a CPU 301, which can execute various appropriate actions and processes according to the program stored in the ROM 302 or the program loaded into the RAM 303 from the storage section 308, such as executing the method described in the above embodiments. In the RAM 303, various programs and data required for system operation are also stored. The CPU 301, ROM 302, and RAM 303 are connected to each other via a bus 304. The I / O interface 305 is also connected to the bus 304.

[0081] The following components are connected to the I / O interface 305: an input section 306 including an audio input device, a button switch, etc.; an output section 307 including a liquid crystal display (LCD), an audio output device, an indicator light, etc.; a storage section 308 including a hard disk, etc.; and a communication section 309 including a network interface card such as a LAN (Local Area Network) card, a modem, etc. The communication section 309 performs communication processing via a network such as the Internet. A drive 310 is also connected to the I / O interface 305 as needed. A removable medium 311, such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, etc., is installed on the drive 310 as needed so that the computer program read from it can be installed into the storage section 308 as needed.

[0082] In particular, according to an embodiment of the present invention, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, an embodiment of the present invention includes a computer program product that includes a computer program carried on a computer-readable medium, and the computer program includes a computer program for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network through the communication section 309, and / or installed from the removable medium 311. When the computer program is executed by the CPU 301, various functions defined in the present invention are executed.

[0083] It should be noted that specific examples of computer-readable storage media may include, but are not limited to: electrical connections with one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), flash memory, optical fibers, portable compact disc read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the above. In the present invention, a computer-readable storage medium can be any tangible medium that contains or stores a program, and the program can be used by or in conjunction with an instruction execution system, apparatus, or device.

[0084] The flowcharts and block diagrams in the accompanying drawings illustrate the possible architectures, functions, and operations of systems, methods, and computer program products according to various embodiments of the present invention. Among them, each block in the flowchart or block diagram may represent a module, a program segment, or a part of code, and the above module, program segment, or part of code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the block may occur in a different order than marked in the accompanying drawings.

[0085] Specifically, the controller of this embodiment includes a processor and a memory. A computer program is stored on the memory. When the computer program is executed by the processor, the flood flow warning method provided in the above embodiment is implemented.

[0086] On the other hand, the present invention also provides a computer-readable storage medium. The storage medium may be included in the controller described in the above embodiment; or it may exist separately and not be assembled into the controller. The above storage medium carries one or more computer programs. When the one or more computer programs are executed by a processor of the controller, the controller is enabled to implement the flood flow warning method provided in the above embodiment.

[0087] As described above, the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the various embodiments of the present application.

[0088] As used in the foregoing embodiments, depending on the context, the term "when..." can be interpreted to mean "if...", or "after...", or "in response to determining...", or "in response to detecting...". Similarly, depending on the context, the phrase "when determining..." or "if detecting (the stated condition or event)" can be interpreted to mean "if determining...", or "in response to determining...", or "when detecting (the stated condition or event)", or "in response to detecting (the stated condition or event)".

[0089] Those of ordinary skill in the art can understand all or part of the processes in the methods of the above embodiments. These processes can be completed by hardware instructed by a computer program, and the program can be stored in a computer-readable storage medium. When the program is executed, it can include the processes of the above method embodiments. The foregoing storage media include: various media that can store program codes, such as ROM or random access memory RAM, magnetic disks, or optical discs.

Claims

1. A flood flow early warning method, characterized in that: Applied to a controller, the method comprises: Controlling the emergency current meter to transmit a first frequency modulated continuous wave to the water surface at a current position and receiving a first signal reflected by the water surface; When the frequency spectrum characteristic of the first signal shows a double peak feature, the emergency current meter is controlled to transmit a second frequency modulated continuous wave to the water surface at the current position, and receive a second signal reflected by the water surface, wherein the double peak feature is used to characterize the existence of stratified flow in the water body, and the frequency interval between the second frequency modulated continuous wave and the first frequency modulated continuous wave is greater than a preset frequency threshold; Determine the surface flow velocity and the sub-surface flow velocity according to the first signal, the second signal and a preset flow velocity calculation formula; Based on the surface flow velocity and the subsurface flow velocity, calculating a water flow stratification coefficient to determine a comprehensive flow velocity; Extracting the section coefficient that best matches the flow pattern characteristics corresponding to the water flow stratification coefficient from a preset section coefficient database; Substituting the comprehensive flow velocity, the section coefficient and the measured water level collected by the emergency flow meter into a preset flow calculation formula to obtain the instantaneous flow of the target section; When the instantaneous flow rate is greater than a preset flow rate threshold, an early warning is issued.

2. The method according to claim 1, characterized in that When the frequency spectrum characteristic of the first signal has a double peak characteristic, before the step of controlling the emergency current meter to transmit a second frequency modulated continuous wave to the water surface at the current position and receiving the second signal reflected by the water surface, the method further includes: Performing frequency domain transformation on the first signal to obtain first spectrum data; Extracting peak points whose amplitudes are greater than a preset amplitude threshold in the first spectrum data; If two peak points are detected, the frequency difference and amplitude ratio of the two peak points are calculated; When the frequency difference is greater than a preset frequency difference threshold and the amplitude ratio is within a preset ratio range, calculating a trough depth coefficient between the two peak points; It is determined whether the frequency spectrum characteristics of the first signal have a double peak feature according to the trough depth coefficient.

3. The method according to claim 1, characterized in that The determining of the surface flow velocity and the sub-surface flow velocity according to the first signal, the second signal and a preset flow velocity calculation formula specifically includes: Extracting the surface reflection peak frequency and the sub-surface reflection peak frequency respectively according to the frequency spectrum characteristics of the first signal and the frequency spectrum characteristics of the second signal; Substituting the surface reflection peak frequency and the emission frequency of the first frequency modulated continuous wave into the preset flow velocity calculation formula to obtain the surface flow velocity; Substituting the subsurface reflection peak frequency and the emission frequency of the second frequency modulated continuous wave into the preset flow velocity calculation formula to obtain the subsurface flow velocity; The preset flow rate calculation formula is: ; Among them, V represents the flow velocity, f represents the reflection peak frequency, ft represents the transmission frequency, c represents the propagation speed of electromagnetic waves in the medium, and θ represents the angle between the frequency modulated continuous wave and the flow rate.

4. The method according to claim 1, characterized in that: The calculating of the water flow stratification coefficient based on the surface flow velocity and the sub-surface flow velocity specifically includes: Extracting a first energy value of a surface reflection peak in the first signal spectrum and a second energy value of a sub-surface reflection peak in the second signal spectrum; Dividing the first energy value by the sum of the first energy value and the second energy value to obtain a surface energy ratio; When the surface energy ratio is greater than the preset first energy threshold, the water flow stratification coefficient is set to 1; When the surface energy ratio is less than the preset second energy threshold, the water flow stratification coefficient is set to 0; When the surface energy proportion is between the first energy threshold and the second energy threshold, the water flow stratification coefficient is set equal to the surface energy proportion.

5. The method according to claim 4, characterized in that The calculation of the water flow stratification coefficient to determine the comprehensive flow rate specifically includes: If the water flow stratification coefficient is greater than a preset first threshold, the surface flow velocity is used as the comprehensive flow velocity; If the water flow stratification coefficient is less than a preset second threshold, the sub-surface flow velocity is used as the comprehensive flow velocity; If the water flow stratification coefficient is between the preset first threshold value and the preset second threshold value, the surface flow velocity and the sub-surface flow velocity are weightedly summed to obtain the comprehensive flow velocity.

6. The method according to claim 1, characterized in that The preset flow calculation formula is: Q=K×VC×A×(1+α×H / Href); Among them, Q represents the instantaneous flow rate of the target section, K represents the section coefficient, VC represents the comprehensive flow velocity, A represents the water flow section area, α represents the water level correction coefficient, H represents the measured water level, and Href represents the reference water level.

7. The method according to claim 1, characterized in that After the step of issuing an early warning when the instantaneous flow rate is greater than a preset flow rate threshold, the method further comprises: Acquiring historical water level data of the target section; Extracting water level change characteristic parameters based on the historical water level data, wherein the water level change characteristic parameters include water level rise rate, water level duration and maximum water level value; Extracting flow change characteristic parameters based on the instantaneous flow, wherein the flow change characteristic parameters include flow peak value, flow rising rate and flood peak duration; A flood characteristic analysis is performed on the water level change characteristic parameters and the flow rate change characteristic parameters to determine the flood type of the target section.

8. A controller, characterized in that: The controller includes: one or more processors and a memory; the memory is coupled to the one or more processors, the memory is used to store computer program code, the computer program code includes computer instructions, and the one or more processors call the computer instructions to enable the controller to execute the method described in any one of claims 1-7.

9. A computer-readable storage medium comprising instructions, characterized in that: When the instructions are executed on a controller, the controller is caused to execute the method according to any one of claims 1 to 7.

10. A computer program product, characterized in that When the computer program product runs on a controller, the controller is caused to execute the method according to any one of claims 1 to 7.

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