51 results about "Field propagation" patented technology

The invention provides a metal material defect identification and analysis method and system based on a multiple detection technology, and relates to the technical field of metal defect detection, and the method comprehensively utilizes microscope detection and ultrasonic detection technologies to obtain surface topography data and internal structure data of a target metal material. And performing feature alignment and fusion processing on the two types of data through a multi-grid method to generate a unified feature distribution model, and establishing a mathematical solution model of ultrasonic wave field propagation based on the model. And determining the position, shape and size information of the potential defect by using the solved data, and generating defect positioning data containing three-dimensional coordinates and contour features. And extracting key defect information in combination with an edge detection algorithm, judging defect types by adopting a classification algorithm, and generating a detection result. According to the method, the problems of insufficient detection precision, high data fusion difficulty and low classification efficiency in the prior art are solved, and the applicability and reliability of a defect detection technology are improved.

The invention discloses a GIS equipment defect accurate positioning method and system based on acoustic visualization, and relates to the technical field of defect localization, and the method comprises the steps: collecting a vibration acoustic mixed signal in an equipment operation state, and separating the vibration acoustic mixed signal into a pure acoustic signal and a vibration signal through independent component analysis; an acoustic characteristic spectrum is constructed for the pure acoustic signals, a sound field propagation path model is generated, and meanwhile a corresponding relation graph of equipment components and the acoustic characteristic spectrum is established; and determining a source component and a specific position of the abnormal acoustic characteristic spectrum through an acoustic reverse tracking positioning algorithm in combination with the sound field propagation path model and the corresponding relation map. According to the method, by combining vibration acoustic conjoint analysis and acoustic reverse tracking, high-precision positioning of defects of hidden parts in the GIS equipment is achieved, the positioning precision and the recognition accuracy are improved, recognizable defect types are expanded, and the method is suitable for GIS equipment of different structures.

The invention discloses a sound source localization method based on multi-frequency separation and Newton optimization deconvolution, relates to the technical field of array acoustic signal processing, and is used for solving the problem that weak sound sources and multiple sound sources are difficult to identify. According to the method, dominant frequency is extracted through multichannel frequency domain analysis, a cross-spectrum matrix is constructed in combination with a near-field propagation model and a guide vector, delay summation beam forming is executed to obtain sound source preliminary distribution, then the distribution is regarded as a convolution result, a maximum likelihood model is introduced, and a two-stage deconvolution strategy of coarse estimation and Newton method fine optimization is adopted to obtain a high-resolution sound source. According to the multi-sound-source positioning method, subgrid-level analysis of sound source positions and amplitudes is achieved, finally, all frequency results are fused, continuous sound source images are smoothly output through a two-dimensional Gaussian kernel, the resolution and real-time performance of multi-sound-source positioning are remarkably improved, and the multi-sound-source positioning method is suitable for high-precision acoustic imaging in a complex sound field.

The invention discloses an underwater target positioning method and system based on dynamic error suppression, and a terminal, and the method comprises the steps: obtaining a vibration signal of an underwater target through a distributed optical fiber sound wave sensing technology, obtaining a rough position of the underwater target according to the vibration signal, and carrying out the positioning of the underwater target according to the rough position; obtaining a first time difference through a sound field propagation phase compensation model, and correcting the phase distortion of the rough position according to the first time difference to obtain a first accurate position; acquiring strain data of the optical fiber, obtaining an actual curvature radius of the sound wave propagation path by using the strain data, obtaining a second time difference according to the actual curvature radius, and correcting the deformation of the optical cable at the first accurate position according to the second time difference to obtain a second accurate position; dynamically compensating the sound path difference according to the second time difference to obtain a corrected sound path difference, and obtaining a final accurate position according to the corrected sound path difference; and performing coordinate conversion on the final accurate position to obtain a real coordinate. According to the invention, the precision of underwater target positioning is obviously improved.

The invention discloses an intraocular light field simulation method and system based on physiological constraint and pathology traceability, the system takes a Physics Informed Kolmogorov-Arnold Net (PI-KAN) network as a core, namely physical information KAN, the method comprises the following steps: obtaining personalized parameters of eyeballs; 5-dimensional light field parameters including space, wavelength and time are input into a pre-trained PI-KAN model for light field solving, a three-layer network architecture including an input layer, a hidden layer and an output layer is established, a physical information edge function is constructed, and training is performed through fusion of a Helmholtz equation and a loss function of boundary conditions; generating an OCT image based on the light field solved by simulation; by analyzing side function mapping, visualization and pathological traceability of a light field propagation physical mechanism are realized. According to the method, the sparsity and interpretability of PI-KAN are utilized, the problems that a traditional method is low in calculation efficiency, difficult in high-dimensional modeling, weak in physical constraint and poor in interpretability are solved, millisecond-level, high-precision and interpretable simulation of the eye light field is achieved, and the method is suitable for ophthalmic clinical auxiliary diagnosis, surgical planning and equipment optimization.

The invention relates to the technical field of laser cladding manufacturing, and discloses a light spot size self-adaptive control method for laser cladding additive manufacturing. The method comprises the following steps: according to real-time monitoring data in a laser cladding process, performing multi-dimensional fusion processing on dynamic characteristics of a molten pool to generate a spatial-temporal characteristic tensor containing temperature gradient distribution, molten pool morphology characteristics and spectral characteristic information; inputting the spatial-temporal feature tensor into a depth probabilistic reasoning model, carrying out probabilistic representation on a cladding abnormal state, and outputting a light spot regulation and control parameter vector with confidence; constructing a three-dimensional energy field distribution model according to the vector, and predicting an energy field propagation path and an evolution trend based on a dynamic graph convolutional network; and finally, according to a prediction result, a self-adaptive light spot adjustment mechanism based on the generative adversarial network is constructed, a multi-stage light spot adjustment threshold dynamically changing along with the cladding process is generated, self-adaptive control over the light spot size is achieved, and the cladding forming quality is improved.

Wireless communication assisted by a reconfigurable intelligent surface under near-field propagation faces the problem of array gain loss, and the increase of system capacity is limited. In order to further improve the communication system capacity of a large-scale intelligent reflecting surface (XL-RIS) in a near field and compensate for serious path loss, the invention provides a multi-user wireless communication system assisted by optimally deploying the large-scale intelligent reflecting surface, so that the near field range is further expanded, and the system capacity is improved. And the XL-RIS topological structure and the beam design are jointly optimized by taking the minimization of the beam gain error expected by the user as a target. In order to solve the non-convex problem, a self-adaptive tabu search algorithm, a Major-Minimization (MM) algorithm and the like are used for converting the sub-problems, and then alternate iterative optimization is carried out on the sub-problems. Particularly, on the premise that hardware cost is not increased, extra spatial freedom is obtained through selection of element positions, the user sum rate is effectively improved, and beam pointing is closer to the direction expected by the user. A simulation result verifies the effectiveness of the method, and a new solution thought is provided for the application of the XL-RIS in a near field communication system.

The invention discloses a near-field ISAC system channel estimation and waveform optimization method based on DPSS. The method comprises the following steps: establishing a near-field ISAC channel and a signal model; designing a channel estimation scheme; designing a joint communication perception optimization problem; based on the designed joint communication perception optimization problem, a joint optimization algorithm under a full-digital architecture is designed; and then designing a joint optimization algorithm under the hybrid beam architecture based on the designed joint communication perception optimization problem. Compared with a DFT codebook structure and a spherical codebook structure, the method has higher energy concentration and lower inter-column correlation, energy leakage can be effectively reduced, channel sparsity is improved, and channel estimation precision is remarkably improved. Besides, the DPSS structure is more suitable for near-field propagation characteristics, and high-precision channel estimation is realized under limited pilot frequency resources in combination with a compressed sensing method, so that the communication and sensing performance is improved in a near-field ISAC system.

The invention provides a false enterprise information identification and traceability method and system based on a structured field propagation chain. The method comprises the following steps: constructing a field propagation chain atlas based on a relationship between fields in an enterprise database; aiming at field values of a target field in the field propagation chain atlas in different time periods, calculating a change trend of the field values and a deviation relative to an industry reference or a historical reference, and calculating to obtain a field value evolution score; based on the field propagation chain atlas, obtaining a plurality of related fields having propagation path association with the target field, and generating a rule gating judgment result for the target field through a configured structured rule engine; and performing multi-factor fusion calculation based on the field value evolution score of the target field, the field confidence coefficient and the rule gating judgment result to obtain a false information identification result of the target field, and generating a field-level evidence chain corresponding to the identification result.

The invention discloses a super-large-scale MIMO communication system, a user scheduling method thereof and a medium, and relates to the technical field of MIMO communication systems.The method comprises the steps that a channel model containing a spherical wave propagation model is established in a near-field communication scene, and the near-field propagation characteristic that the antenna array size is equivalent to the user distance is considered; obtaining a beam focusing vector of the user based on a channel model; calculating to obtain beam focusing vectors and correlation between the beam focusing vectors; using an alternative optimization algorithm to jointly optimize user scheduling and power distribution, including grouping the users based on the correlation, so that the users in each group have similar channel conditions; and the total spectrum efficiency of the system is maximized under the condition that the minimum spectrum efficiency constraint and the total transmitting power constraint are met. According to the invention, interference among users can be effectively reduced, and the accuracy and efficiency of user scheduling can be improved by an alternative optimization scheduling method.

A near-field DoA estimation method based on CCKAN is proposed. In the offline stage, the received signals of array element channels are simulated. Based on the near-field propagation model, simulated signals affected by near-field effects are generated as a sample set. Feature data of the received signals of each array element channel are extracted from this sample set. Empirical autocorrelation is used to obtain the covariance features of the received signals, which are then used to train the constructed CCKAN. In the online stage, real-time DoA estimation is performed using the trained CCKAN. This invention introduces complex-valued convolution into the Kolmogorov-Arnold network (KAN). By simulating complex-valued operations in the convolution, the intrinsic relationship between signal amplitude and phase is enhanced. Simultaneously, the more interpretable KAN is introduced as a feature extraction method, achieving excellent DoA resolution under both far-field and near-field conditions.

The invention discloses a weak sound source sound pressure level calibration method based on an improved DAS beam, relates to the technical field of sound source positioning, and is used for solving the problem of repeated weak sound source positioning. According to the method, a distance matrix is constructed based on array geometric parameters, and a cross spectrum matrix and a steering vector are respectively calculated for a plurality of target frequencies in combination with a near-field propagation model to obtain a multi-frequency acoustic image; and performing normalization and relative threshold side lobe suppression on each frequency sound image result, superposing and highlighting a real sound source area on a scanning grid, suppressing a side lobe irrelevant to a position, and utilizing a sound pressure level calibration model obtained by training reference data to convert a sound image output quantity into a real sound pressure level, so as to realize spatial positioning and quantitative sound pressure evaluation of multiple sound sources. The weak sound source can still be clearly distinguished under the background that the sound pressure level difference of the strong and weak sound sources is large and the noise is complex, and the sound source positioning precision and the engineering detection reliability are improved.

The invention provides a channel modeling method, device and equipment for near-field spatial non-stationary characteristics, and the method comprises the steps: determining the propagation distance of each scatterer cluster in a near-field propagation space according to the cluster time delay information of the scatterer clusters and the pre-configured distance information of the scatterer clusters; wherein the distance information comprises distance distribution information between the scatterer cluster and the signal transmitting end and / or the signal receiving end; generating space coordinate information of the scatterer cluster according to the arrival angle information, the departure angle information and the propagation distance of the scatterer cluster; determining near-field propagation channel parameters according to the space coordinate information; obtaining a non-stationary attenuation factor of the near-field propagation space according to the parameter information and the position information of the shielding object in the near-field propagation space; and on the basis of a standard channel model, according to the near-field propagation channel parameters and the non-stationary attenuation factors, constructing a channel model with near-field spatial non-stationary characteristics. The channel model constructed by the embodiment of the invention is high in accuracy, and the complexity of the calculation process is low.

The present application relates to the technical field of laser cladding manufacturing, and discloses a kind of laser cladding additive manufacturing light spot size adaptive control method.The method is according to the real-time monitoring data in laser cladding process, the dynamic characteristics of molten pool are multidimensional fusion processing, generate the space-time characteristic tensor containing temperature gradient distribution, molten pool topographic feature and spectral feature information;Again, the space-time characteristic tensor is input into deep probability inference model, and the abnormal state of cladding is probabilisticly characterized, and the light spot regulation parameter vector with confidence is output;Then, according to the vector, a three-dimensional energy field distribution model is constructed, and the energy field propagation path and evolution trend are predicted based on dynamic graph convolution network;Finally, for the prediction result, an adaptive light spot adjustment mechanism based on generative adversarial network is constructed, and a multi-level light spot adjustment threshold that changes dynamically with the cladding process is generated, to realize the adaptive control of light spot size and improve the cladding forming quality.

Reconfigurable intelligent surface (RIS) assisted wireless communication in near-field propagation suffers from array gain loss, which limits the improvement of system capacity. To further improve the system capacity of large-scale RIS (XL-RIS) assisted wireless communication in near-field and compensate for the severe path loss, an optimized deployment of XL-RIS assisted multi-user wireless communication system is proposed to further expand the near-field range and improve the system capacity. The joint optimization of XL-RIS topology and beam design is performed to minimize the user's expected beam gain error. To solve this non-convex problem, the adaptive tabu search algorithm and Majorization-Minimization (MM) algorithm are used to alternately optimize the transformed sub-problems. Especially, without increasing the hardware cost, the selection of element positions obtains additional spatial degrees of freedom, effectively improves the user and rate, and makes the beam pointing closer to the user's expected direction. The simulation results verify the effectiveness of the proposed method, which provides a new solution for the application of XL-RIS in near-field communication systems.

The application discloses a phase recovery method based on single fractional Fourier transform amplitude observation, and comprises the following steps: S1, a near-field observation model based on fractional Fourier transform is established according to optical propagation theory; S2, corresponding single fractional Fourier transform amplitude observation information is obtained by simulation according to the established near-field observation model; S3, a phase recovery algorithm based on generalized alternating projection method is established, the single fractional Fourier transform amplitude observation information and signal prior information are taken as inputs, iterative calculation is carried out by using the phase recovery algorithm, and signal reconstruction is realized. The application has the advantages that the requirement of excessive dependence on oversampling or multiple observations is broken, the near-field propagation problem is described by combining a signal processing tool fractional Fourier transform, more accurate and efficient signal reconstruction is realized only from single amplitude observation, and the reconstruction quality is high.

This invention relates to the field of sensors, specifically to a multi-parameter sensing element, a multi-parameter sensor, and its design method for cryogenic applications. The scheme involves setting a reference channel and a sensing channel on a piezoelectric substrate. Each channel includes a SAW resonant unit composed of an interdigital transducer and a reflective grating, the SAW resonant unit being made of superconducting material. A functional sensitive layer is also positioned along the acoustic field propagation path of the SAW resonant unit in the sensing channel, making it sensitive to both temperature and non-temperature environmental parameters associated with the functional sensitive layer. The reference channel contains only the SAW resonant unit and is only sensitive to temperature. The sensor application of this invention allows for precise temperature measurement using the reference channel, and the result can be used to assist the sensing channel in resolving the values ​​of non-temperature environmental parameters. By integrating multiple channels with orthogonal sensing characteristics on the same piezoelectric substrate, this invention achieves independent decoupling of different parameters, enabling disturbance-free, high-sensitivity in-situ monitoring.

Methods, apparatus, devices, and systems for three-dimensional (3D) displaying objects are provided. In one aspect, a method includes obtaining data including respective primitive data for primitives corresponding to an object, determining an electromagnetic (EM) field contribution to each element of a display for each of the primitives by calculating an EM field propagation from the primitive to the element, generating a sum of the EM field contributions from the primitives for each of the elements, transmitting to each of the elements a respective control signal for modulating at least one property of the element based on the sum of the EM field contributions, and transmitting a timing control signal to an illuminator to activate the illuminator to illuminate light on the display, such that the light is caused by the modulated elements of the display to form a volumetric light field corresponding to the object.

The present invention relates to the technical field of underwater target acoustic positioning, and in particular to a high-resolution vertical array broadband matching positioning method. A parabolic equation model is used to calculate a single-step recursive sound field propagation matrix, and a sound source-receiver system propagation matrix at different distances is obtained through matrix multiplication. According to the sound source depth search range and the vertical array element position, the corresponding position coefficients of the system propagation matrix are extracted to form a data copy matrix. Subsequently, the data copy matrix is ​​processed, and a broadband filter matrix group is formed by using a least squares estimation method and increasing a diagonal load factor. Finally, a broadband filter matrix group is used to process the vertical array receiving signal, and energy normalization is performed on the processing results of different distances to form a broadband distance-depth ambiguity map, and the target depth and distance estimation results are obtained. The present invention can effectively improve the depth and distance resolution of broadband signal target passive positioning, reduce the sidelobe intensity in the two-dimensional ambiguity map, and reduce the number of high-intensity sidelobes.

A high-precision above-ground and underground two-way communication trenchless pipeline construction and detection system, comprising a transmitter A, a receiver A, a transmitter B and a receiver B. The transmitter A and receiver B are located underground and arranged at a construction drill pipe at a front end of a drilling rig pipeline; the receiver A and transmitter B are located on the ground and arranged at the position of the guidance operator; the transmitter A and receiver A operate in the same frequency band, with transmitter A configured to transmit electromagnetic waves modulated with digital information. The entire process adopts two-way communication: a set of transmitting and receiving system is arranged on the ground, and another set is arranged underground, forming a closed loop for digital information transmission, which can eliminate impact of interference sources around the ground receiver, and impact of metal interferences during magnetic field propagation.

The invention discloses a method for determining a wave field propagation angle based on sliding window wave-by-wave polarization analysis, and the method comprises the steps: carrying out the data preprocessing based on VSP three-component seismic data for the calculation demands of a wave propagation angle in a three-component multi-wave wave field, carrying out the polarization analysis of a vector end diagram after preprocessing, and carrying out the calculation of the wave propagation angle after a time window is selected; the method comprises the following steps: respectively extracting amplitude information from corresponding original components according to the size and position of a window, integrating different component data of the same window to construct a vector end diagram, further determining a polarization angle and a wave propagation direction by fitting a straight line, and sliding the window to simply and effectively obtain the propagation direction of the whole wave field. The method is simple and efficient in process, large-scale VSP three-component seismic data can be rapidly processed through the sliding window, the data processing efficiency is remarkably improved, high-fidelity wave field propagation characteristic analysis, auxiliary speed modeling and wave field separation can be provided, and the result reliability is improved.

1. The name of the design product: liquid strain on-site expansion equipment shell. 2. The use of the design product: used for the shell of various functional microorganism on-site expansion equipment. 3. The design points of the design product: in shape. 4. The picture or photo that best indicates the design points: perspective view 1.

The present invention discloses a method for channel estimation and waveform optimization of a DPSS-based near-field ISAC system, including: establishing a near-field ISAC channel and a signal model; designing a channel estimation scheme; designing a joint communication and sensing optimization problem; based on the designed joint communication and sensing optimization problem, designing a joint optimization algorithm under a full-digital architecture; and then based on the designed joint communication and sensing optimization problem, designing a joint optimization algorithm under a hybrid beamforming architecture. Compared with the DFT codebook and spherical codebook structures, the present invention can have stronger energy concentration and lower inter-column correlation, can effectively reduce energy leakage, improve the sparsity of the channel, and significantly improve the channel estimation accuracy. In addition, the DPSS structure is more adaptable to the near-field propagation characteristics. Combining with the compressed sensing method, high-precision channel estimation can be achieved under limited pilot resources, thereby improving communication and sensing performance in the near-field ISAC system.

The invention provides a defect detection system based on zone plate array imaging. The defect detection system comprises a light source, a zone plate array and an image acquisition component, wherein the wave zone plate array is formed by arranging a plurality of wave zone plate units, and imaging areas of different wave zone plate units are separated from one another; multiple beams of light emitted by the light source pass through an object to be measured and then enter each zone plate unit on the zone plate array to form a convergent light field, and the convergent light field corresponding to each zone plate unit is transmitted to the image acquisition component to be received and imaged. Compared with the prior art, the zone plate array is adopted for imaging, the field of view of the object space is effectively increased while high-resolution imaging precision is obtained, the defect detection yield can be greatly improved, and therefore the requirement of the industry for the defect detection yield is met.

The present application belongs to the field of coherent diffraction imaging, and specifically discloses a method and system for automatic focusing of coherent diffraction imaging. The present application simulates multiple groups of samples to be tested at different positions through a near-field propagation model, performs wavelet transformation on the simulated samples to be tested to obtain wavelet coefficients, calculates clarity based on the wavelet coefficients, and uses the clarity weights of all simulated samples to update the axial distance to gradually approach the actual value of the axial distance between the sample and the detector, thereby achieving automatic focusing of coherent diffraction imaging. The present application proposes for the first time the use of operators in the frequency domain to calculate the clarity of the reconstructed image. This method has higher axial contrast and noise robustness, greatly improving the convergence speed, accuracy and robustness; through wavelet transform, the detail components of the image in the horizontal, vertical and diagonal directions are extracted in the frequency domain to evaluate the clarity of the reconstructed image, and the weights of different directions can be flexibly adjusted, which has better generalization.

The application discloses a viscoacoustic medium characteristic wave and primary wave combined least square reverse time migration method and belongs to the technical field of oil geophysical exploration. The method constructs a new combined Q least square reverse time migration target function, introduces a viscoacoustic differential equation and an accompanied pseudo-differential equation, describes forward and reverse propagation wave fields of the combined Q least square reverse time migration, deduces Q compensation wave field propagation, Q compensation accompanied operators and Q attenuation migration operators of primary waves, multiple waves, diffracted waves and prism waves, constructs a new gradient formula, and realizes Q least square reverse time migration of combined multiple waves, diffracted waves, prism waves and primary waves in a viscoacoustic medium. The method can accurately image structures under salt, steeply inclined flanks, small faults and rock caves, obtain clearer complex structure information, obtain high-resolution and high-quality imaging diagrams, and solves the problem of unclear imaging of current special complex high-steep structures.

The application discloses an audio playing method and device, electronic equipment and storage medium, and belongs to the technical field of terminal control. The method is applied to the electronic equipment, and comprises the following steps: obtaining a target audio signal to be played; and playing the target audio signal through an audio playing module of the electronic equipment; wherein the audio playing module comprises at least two sound production units and at least two filters, each sound production unit is connected with a filter in correspondence, and the working coefficient of each filter is determined according to the maximum energy contrast of a test audio signal between a near-field propagation area and a far-field propagation area, and the distance between the near-field propagation area and the audio playing module is smaller than the distance between the far-field propagation area and the audio playing module. The application can reduce the signal leakage of the audio signal in the far-field propagation area, and improve the confidentiality of the audio signal.

The present invention discloses a method for determining the wavefield propagation angle based on sliding window-by-wave polarization analysis. Aiming at the calculation requirement of wave propagation angles in three-component multi-wave wavefields, data preprocessing is performed based on VSP three-component seismic data. Then, polarization analysis is carried out on the processed hodograph. After selecting a time window, amplitude information is extracted from the corresponding original components according to the size and position of the window respectively. The data of different components in the same window are integrated to construct a hodograph, and by fitting a straight line, the polarization angle and the wave propagation direction are determined. By sliding the window, the propagation direction of the entire wavefield is simply and effectively obtained. The method flow of the present invention is concise and efficient. Using the sliding window can quickly process large-scale VSP three-component seismic data, significantly improve the data processing efficiency, and can provide high-fidelity wavefield propagation characteristic analysis to assist velocity modeling and wavefield separation, improving the reliability of the results.

The invention provides a three-dimensional sound wave propagation simulation method based on a multi-relaxation time lattice Boltzmann model, and belongs to the crossing field of geophysical exploration and computational acoustics. Comprising the following steps: 1) constructing a three-dimensional mathematical model based on an actual geological structure; 2) establishing a 3D-MLBM equation, and modifying a migration process to obtain an iterative computation format of the sound wave field quantity; 3) setting physical parameters, processing boundary conditions and initializing simulation conditions; 4) simulation of sound wave field propagation is carried out, and wave field information at different moments is recorded; and 5) carrying out quantitative comparison on the performance of the D3Q15-MLBM and the performance of the D3Q27-MLBM, optimizing model parameters, and analyzing and applying a result. And analyzing a model result, establishing a multi-dimensional performance evaluation system, and applying the multi-dimensional performance evaluation system to seismic wave field simulation and inversion of a large-scale three-dimensional geologic model.