12 results about "Propagation equation" patented technology

The invention discloses a monitoring equipment fault rapid positioning method based on causal diagram reasoning, and the method comprises the following steps: building a thermal diffusion model composed of equipment nodes and links through collecting the topological structure and operation data of a monitoring system; normalizing and fusing the operation deviation information into a node abnormal energy value, and establishing an abnormal energy propagation equation; when an alarm is triggered, collecting an energy change sequence of each node to generate a space-time energy distribution matrix, and reversely solving a thermal diffusion equation to calculate a disturbance source item; performing clustering backtracking on disturbance source items, determining fault root cause nodes, and comprehensively evaluating confidence; and when multi-source abnormity exists, thermal field orthogonal decomposition is executed, and model parameters are adaptively updated according to field results. According to the method, abnormal propagation of monitoring equipment is modeled into a thermal diffusion process, and reverse solution and adaptive calibration are combined, so that rapid, explainable and high-precision positioning of fault root causes in a complex monitoring network is realized.

The invention discloses an equal-length matching optimization method for differential pair transmission paths of a high-speed printed circuit board, and belongs to the technical field of signal integrity modeling and simulation. Comprising the following steps: constructing a multi-conductor transmission line model containing a reference conductor, extracting a parameter matrix per unit length, judging the uniformity and symmetry of a structure, and introducing a local modal substrate and a continuous modal coupling term which change along with space for describing modal conversion caused by gradual change of the structure, the propagation delay inequality of the two signal paths is calculated, a phase calibration operator is constructed, modal conversion and the delay mismatch effect are brought into a unified propagation equation to be solved, the phase calibration operator is applied at a recoupling reference plane to carry out alignment processing on voltage and current, and finally equivalent differential mode impedance is obtained through calculation. According to the method, integrated modeling is carried out by integrating the joint effect of mode conversion and time delay mismatch, and the impedance simulation precision of the difference pair snake-shaped compensation structure recoupling region is remarkably improved.

The application provides a gear fatigue crack propagation life calculation method and system considering random dynamic load, and the method is as follows: a local plane coordinate system is established at a crack tip, and a crack propagation equation is constructed; time-varying mesh stiffness containing a tooth root crack feature is calculated; a vibration differential equation of a gear mesh pair is constructed and solved, and dynamic meshing forces of the gear pair under different crack states are obtained; the dynamic meshing forces of the gear pair under different crack states are processed, and a load spectrum is prepared, and variable amplitude load data with multi-periodicity are obtained; the variable amplitude load data are taken as boundary conditions, crack propagation is simulated, gear fatigue crack propagation data are read from a finite element data file; stress intensity factors are calculated based on the gear fatigue crack propagation data; and fatigue crack propagation life is estimated based on the Paris formula and the stress intensity factors. The method can improve the reliability and fatigue crack propagation life of the gear, improve the safety of equipment, and reduce maintenance costs.

Systems, devices, methods, and computer-readable media for concurrent visualization of sensor and communications operations. A method can include receiving mission data indicating a target, a sensor, a communications system, and an operation to be performed regarding the target, identifying one or more operational layer, functional layer, and physical layer models for the sensor and communications system, and a physical layer model for weather, identifying, based on a comparison of the physical models of the sensor and communications system to a propagation equation, any gaps or inconsistencies between the physical models of the sensor and communications system and the propagation equation, and executing a simulation model resulting in a visual display of execution of the mission using the sensor and the communications system, the simulation model generated based on a filler model that fills any identified gaps or fixes any identified inconsistencies.

The present application relates to the technical field of dangerous rock monitoring, and particularly relates to a dangerous rock monitoring system and a risk assessment method thereof.The present application introduces a graph convolutional neural network to accurately model environmental factors such as wind speed and vegetation, overcomes the limitations of traditional wind force calculation models, corrects the influence of wind force tension, and thus more accurately assesses the stability of the rock mass;By introducing a dynamic adjustment mechanism of the environmental change coefficient and the vibration propagation coefficient, the model can adapt to changes in environmental factors such as temperature, humidity and precipitation in real time, and improve the adaptability and accuracy of the model;In addition, considering the spatial interaction and dynamic effect between rock mass units, an instability propagation equation is established to capture the propagation process of rock mass instability, so as to comprehensively consider the physical properties, spatial interaction and environmental changes of the rock mass, thereby providing more accurate and real-time instability prediction, and providing effective risk warning and emergency decision assistance for mining, slope construction and other engineering.

The invention discloses a method and device for suppressing a current fundamental component based on a particle filter, and belongs to the technical field of motor fault diagnosis, and the method comprises the steps: constructing a particle swarm used for estimating the fundamental component based on a collected stator line current signal, each particle in the particle swarm having two parameters, namely an amplitude and an initial phase, the two parameters respectively meet preset normal distribution and uniform distribution; carrying out propagation and weight updating on the particle swarm through a propagation equation and distribution of measured values, estimating state values of a stator line current fundamental frequency component at different sampling moments, and obtaining a fundamental frequency component estimation value; and subtracting the estimated value of the fundamental component from the collected stator line current signal to obtain a current signal after the fundamental component is suppressed. According to the method, the proper particle swarm is constructed, so that the fundamental frequency component accurate estimation based on the particle filter is realized, the fundamental frequency component in the stator line current is effectively inhibited, the identifiability of the fault characteristic current harmonic wave is improved, and the reliability of asynchronous motor fault diagnosis is improved.

The invention provides a power transmission line audible noise simulation method based on machine learning and PINN, and the method comprises the steps: training a machine learning model through employing a first data set, and obtaining a first prediction model; according to the set environment characteristics, using a first prediction model to predict and obtain a plurality of audible noises; using a plurality of audible noises as boundary condition loss, using an acoustic propagation equation as physical loss, and training a PINN model to obtain a second prediction model; and using the second prediction model to predict the audible noise under the space coordinates of the power transmission line, and rendering according to the numerical value of the audible noise under the space coordinates of the power transmission line to obtain a simulation result of the audible noise of the power transmission line. Compared with the prior art that it is difficult to achieve transmission line audible noise simulation under the complex meteorological environment condition quickly and accurately with low calculation overhead, the method has the advantages that audible noise simulation capable of responding to the complex meteorological environment is achieved, and it is guaranteed that the simulation process is quick, accurate and low in calculation overhead.

The invention discloses an algebraic iteration photoacoustic image imaging method based on an acoustic transmission model, and belongs to the technical field of photoacoustic / ultrasonic imaging. Comprising the following steps: S1, designing a photoacoustic imaging system based on photoacoustic and ultrasonic bimodal; S2, discretizing an ultrasonic signal forward propagation equation; s3, calculating a forward model; and S4, constructing a forward propagation equation and iteratively solving the initial sound pressure. A traditional photoacoustic reconstruction method is influenced by limited bandwidth and limited visual angle of a transducer, so that reconstructed images are often influenced by artifacts. According to the method, the iterative reconstruction method based on the sound transmission model is introduced, so that the phenomena of high artifacts and multiple side lobes existing in a traditional image reconstruction algorithm are effectively inhibited. The invention provides a new method for reconstructing the photoacoustic image, and the resolution of the reconstructed image based on the photoacoustic effect is remarkably improved. In the process of iteratively solving the forward propagation equation, the regularization method is introduced, the convergence direction of the iterative solution is controlled by the L2 norm information of the initial sound pressure, and the robustness of the reconstructed image influenced by noise is effectively enhanced.

The invention relates to a consistent multi-center relative navigation method used under resource limitation. The invention relates to the technical field of relative navigation. The method comprises the following steps: constructing a multi-center relative navigation error state modeling and global error discrete time propagation equation; establishing an absolute measurement and relative measurement model; constructing a process noise covariance upper bound matrix based on the maximum speed boundary; performing consistent multi-center extended Kalman filtering based on an upper bound matrix; and outputting error feedback correction and a relative navigation result. According to the method, consistent propagation of process noise can be realized under the condition of not depending on high-frequency information of other machines, the stability and robustness of multi-center relative navigation are remarkably improved, and the method has important practical application value.

The application discloses a high-speed printed circuit board differential pair transmission path equal-length matching optimization method and belongs to the technical field of signal integrity modeling and simulation. The method comprises the following steps: constructing a multi-conductor transmission line model containing a reference conductor and extracting a per-unit-length parameter matrix; judging structural uniformity and symmetry; introducing a spatially-varying local modal basis and a continuous modal coupling term for describing the modal conversion caused by the gradual change of the structure; calculating the propagation time delay difference of two signal paths and constructing a phase calibration operator; integrating the modal conversion and the time delay mismatch effect into a unified propagation equation for solving; and applying the phase calibration operator to align the voltage and current at the recoupling reference surface, so that the equivalent differential mode impedance is finally calculated. The application integrates the combined effects of modal conversion and time delay mismatch for integrated modeling, and significantly improves the impedance simulation accuracy of the recoupling area of the differential pair serpentine compensation structure.

The application provides a positioning method, device and medium based on a solid-state laser radar and inertial navigation, feature points of the solid-state laser radar are extracted based on geometry and intensity by acquiring measurement values of an inertial sensor, and influence of motion blur on collected data is reduced; in a state propagation process of an iterative error Kalman filtering algorithm, the measurement values of the inertial sensor are taken as propagation error states, a discrete propagation equation is constructed, an iterative residual error vector is calculated by using the feature points of the solid-state laser radar, states in the iterative error Kalman filtering algorithm are updated, Kalman gain in the iterative error Kalman filtering algorithm is adjusted, the pose estimation result of the positioning algorithm is effectively improved, the positioning precision and robustness are improved, finally, parameters of the feature points of the solid-state laser radar and the measurement values of the inertial sensor are synthesized based on the iterative error Kalman filtering algorithm, a global pose is updated, and accurate positioning is realized.

The invention discloses a lumped model-based rapid modeling method for a quantum well semiconductor optical amplifier. The method comprises the following steps of: S1, extracting parameter data; s2, constructing a lumped model; s3, performing numerical simulation calculation; s4, extracting design parameters; and S5, system-level simulation optimization is carried out. Compared with an existing space-time two-dimensional device model, the lumped model-based rapid modeling method for the quantum well semiconductor optical amplifier has the advantages that original two-dimensional space-time solution is simplified into one-dimensional time solution by integrating a space propagation equation and combining reasonable approximation, so that the calculation efficiency is improved in an order of magnitude manner, and the modeling precision is improved. The time domain simulation speed of the quantum well semiconductor optical amplifier can be obviously improved, and the calculation time consumption of device and system joint debugging in the parameter extraction and optimization design process is effectively shortened.