36 results about "Propagation equation" patented technology

The invention discloses a method for calculating cable interference in an infinite shielding layer with holes in a point source radiation field, is applied to the field of electromagnetic interference, and has the advantages of simple algorithm, accurate result, high efficiency and the like. In that method, the aisle of the voltage wave on the cable and the propagation aisle of the space electromagnetic field are represented by signal pipelines, the position with the energy reflection is represented by nodes, a signal flow graph reflecting the electromagnetic energy flow of the system is established, the propagation equation of the whole system signal pipeline and the scattering equation on all the nodes are established by using the magnetic flow element radiation instead of the small holetransmission, the extended BLT (Baum-Liu-Tesche) equation of the system electromagnetic interference is obtained, and the interference intensity on the cable is obtained by solving the extended BLT equation. The method realizes the accurate calculation of the electromagnetic interference of the point source radiation field in the infinite shielding layer with holes and is coupled to the transmission line, and the method effectively reduces the dependence on the computing resources and improves the efficiency.

The invention discloses a level set topological optimization method, system and equipment and a medium, and belongs to the field of structural design topological optimizing. The method comprises the steps that a design area corresponding to a to-be-optimized object is divided into a plurality of finite element units, and a level set function and a boundary propagation equation of the finite element units are established; the strain energy density of each finite element unit is sequentially subjected to space smooth filtering and time smooth filtering, the value of a Lagrange multiplier in the boundary propagation equation is updated to be the Nsth small strain energy density after filtering, and Ns is the number of solid finite element units needing to be removed currently; topological optimization is performed based on the updated boundary propagation equation and the level set function to reduce the flexibility of the design area; and the calculation, filtering, updating and optimization operations are repeatedly executed until the flexibility of the optimized design area is converged to the minimum. A parameter-free method is proposed to determine the Lagrange multiplier, so that the problems of inaccurate volume constraint, low calculation efficiency, unstable convergence and the like in the existing method can be effectively solved.

The invention provides a noise prediction and layout optimization method for a flat terrain wind power plant. The noise prediction and optimization layout method for the flat terrain wind power plantcomprises the following steps that 1, on the basis of a wind power plant engineering wake flow model, generating the incoming flow wind speed of each wind turbine in the wind power plant, and calculating the aerodynamic noise source of each wind turbine; 2, simplifying the three-dimensional PE parabolic equation, and calculating a wind turbine noise propagation database based on a two-dimensionalnoise propagation equation of a single wind turbine; Step 3, according to the wind turbine noise propagation database obtained in the step 2, carrying out wind power plant noise numerical simulation calculation by using a wind power plant noise propagation multidimensional interpolation formula; And 4, optimizing the optimized layout of the wind power plant meeting the sound pressure level contourline by adopting a maximum sound pressure boundary value taking method.

The embodiment of the invention provides a target classification method for double-path coupling deep learning based on a sound wave propagation equation. A category to which the to-be-classified target belongs is determined by adopting a preset deep neural network classification model; the hidden layer has a two-way coupling structure and a cross-layer jump connection structure, the SWTNN classification model can have the double-path coupling capacity and the jumping connection capacity between layers at the same time, the problem of gradient disappearance can be solved, the training precision and the classification precision of the SWTNN classification model are improved, and then the efficiency and the accuracy of determining the category to which the to-be-classified target belongs are greatly improved. Moreover, the SWTNN classification model adopted in the embodiment of the invention is constructed based on a frequency domain first-order sound wave propagation equation and a finite difference algorithm, has clear physical and mathematical significance, is an interpretable deep neural network classification model, is another important technical breakthrough, and has very high innovativeness.

The invention provides an inertial navigation method, electronic equipment, a storage medium and a computer program product. The method comprises the following steps: acquiring acceleration and angular velocity output by an inertial measurement unit, and generating a state propagation equation of extended Kalman filtering based on a kinematic model of the inertial measurement unit; based on the state propagation equation, performing state prediction on the target equipment deployed with the inertial measurement unit to obtain a state prediction value; inputting the acceleration and the angular velocity into a target prediction model, performing observation noise covariance prediction, and obtaining an observation noise covariance output by the target prediction model; and constructing a state updating equation of extended Kalman filtering based on the observation noise covariance, and updating the state prediction value based on the state updating equation to obtain a state optimization value for navigation positioning. According to the method, the accuracy of Kalman filtering can be improved through deep learning, so that the more accurate observation noise covariance is obtained, and the positioning precision of the inertial measurement unit is improved.

The invention relates to a three-dimensional reconstruction method and system based on a photogrammetric photometric stereo model. The method comprises the following steps: reading an internal orientation attitude, an external orientation attitude parameter and an incident light vector of a camera; substituting the parameters into a photogrammetry collinear equation and an error propagation equation to calculate a normal vector of an object space coordinate; according to the normal vector and the incident light vector, solving a cosine function of a light incident angle, an emergent angle anda phase angle; establishing a radiation equation of the image according to the incident angle, the emergent angle and the phase angle of the light; according to the radiation equation of the image, performing iterative solution to obtain gradient values of the elevation in the x and y directions of the image space coordinates; according to the gradient values of the image space coordinates in thex direction and the y direction, obtaining the relative elevation value of each point through least square solution, and therefore a reconstructed three-dimensional model is obtained. The limitation that three attitudes of a camera in a traditional photometric stereo are all 0 degree can be effectively broken through, the application range of the photometric stereo in close-range photogrammetry isexpanded, and the relative elevation value of an object is recovered.

The invention relates to an aviation network sweep effect inference method based on two-stage regression, belongs to the technical field of flight delay prediction, and solves the problem that an existing delay propagation analysis model is solidified and established based on idealized hypothesis. Comprising the following steps: constructing an adjacent matrix among all airports in each time slice, and generating a delay state vector of each airport; constructing a flight delay model according to the dynamic function library and the adjacent matrix; according to the delay state vector, fitting a flight delay model through an LASSO regression method to obtain a preliminary fitting equation; sampling from all airports to obtain a plurality of airport combinations, optimizing the preliminary fitting equation corresponding to each airport combination by adopting a weighted akaike information criterion to obtain an optimization equation corresponding to each airport combination, and obtaining a delay propagation equation based on each optimization equation; and obtaining delay time of all airports in corresponding time slices according to the delay propagation equation, and taking the delay time as an inference result of the aviation network sweep effect. And accurate prediction of the aviation network sweep effect is realized.

The invention provides an anti-dispersion seismic wave forward modeling method, system and device and a medium. The method comprises the following steps of obtaining an underground medium velocity field and a forward modeling wavelet dominant frequency, and setting a first projection relation according to the underground medium velocity field and the forward modeling wavelet dominant frequency, re-sampling in the depth direction according to the first projection relation to generate a second velocity field, and according to the second velocity field, performing seismic wave field forward modeling through a wave field propagation equation. The method realizes longitudinal frequency dispersion suppression, can balance efficiency and data quality to carry out seismic wave forward modeling, realizes relatively good balance of calculation cost, geologic structure characteristics and data quality, and can be widely applied to the technical field of seismic exploration.

The invention discloses a seismic data processing method for suppressing exogenous interference waves and a storage medium. The seismic data processing method for suppressing the exogenous interference waves comprises the following steps of: inputting initial seismic data; preprocessing the initial seismic data to obtain seismic data to be processed; obtaining coordinates of at least four points of the event of the exogenous interference wave and corresponding travel time; based on the propagation equation of the exogenous interference waves, utilizing the coordinates of the at least four points and the corresponding travel time to construct an equation set; solving the equation set formed by the at least four equations of the at least four points to obtain the coordinates of the exogenousinterference waves and the propagation speed of the exogenous interference waves; and processing the seismic data to be processed according to the coordinates of the exogenous interference waves andthe propagation speed of the exogenous interference waves so as to suppress the exogenous interference waves. According to the seismic data processing method for suppressing the exogenous interferencewaves and the storage medium, the source point position of the exogenous interference waves can be automatically obtained, and the suppression effect of the exogenous interference waves can be betterimproved.

The invention relates to a multilayer medium photoacoustic tomography method. The multilayer medium photoacoustic tomography method comprises the following steps of: illuminating a multilayer medium to be imaged by using pulsed light, receiving acoustic signals generated by the multilayer medium from different positions at multiple angles by using a plurality of transducers arranged in an outer layer medium, and performing Fourier transform on the signals received by each transducer, forming a sound pressure spectrum; according to a resolution requirement of required imaging, carrying out discretization grid division on the multilayer medium based on geometric parameters of the multilayer medium; according to a frequency domain sound propagation equation, selecting a certain number of discrete frequency points, and constructing a model matrix; combining the model matrix with the sound pressure spectrums corresponding to a certain number of discrete frequency points, and constructing a linear equation set; and solving and optimizing the linear equation set. According to the photoacoustic tomography method, the quality of the photoacoustic tomography image in the multilayer heterogeneous medium can be remarkably improved, accurate initial sound pressure distribution is obtained, and high-resolution and high-precision imaging can be completed by automatically setting image resolution according to actual needs.