12 results about "Permittivity distribution" patented technology

The invention relates to the technical field of coal quality detection, in particular to an online detection method and system for the quality of coal as fired. Comprising the following steps: a multi-modal data acquisition step: respectively acquiring a microwave scattering parameter and a surface element characteristic spectrogram through a microwave chromatography sensor array and a surface spectrum detector; a physical field inversion and modeling step: reconstructing a complex dielectric constant distribution diagram based on scattering parameters, and establishing a three-dimensional physical distribution model containing density and moisture; a field-spectrum coupling deduction step: taking the characteristic spectrogram as a boundary constraint, and deducing internal chemical element distribution in combination with the complex dielectric constant distribution diagram; volume weighted quantization: executing volume weighted integration for the three-dimensional physical model and the chemical distribution, and outputting comprehensive coal quality parameters; according to the method, the detection blind area of a single technology is eliminated, and the representativeness and the safety of coal as fired total cross-section detection are remarkably improved.

The invention belongs to the technical field of lunar subsurface material attribute inversion, and relates to a diffraction-reflection combined constraint dielectric constant inversion method for lunar exploration radar data, which comprises the following steps: preprocessing the lunar exploration radar data to obtain a radar profile; diffracted waves and reflected waves are separated from the radar profile; performing medium background impedance inversion based on the diffracted wave to obtain background impedance, and converting the background impedance into logarithmic impedance to obtain logarithmic background impedance; dielectric impedance disturbance inversion is carried out based on the reflected waves, and logarithmic impedance disturbance is obtained; matching and fusing the logarithmic background impedance and logarithmic impedance disturbance in a frequency domain to obtain a full-band impedance model; a dielectric constant distribution is calculated based on the full-band impedance model. By comprehensively utilizing complementary advantages of diffracted waves and reflected waves in dielectric constant inversion, stable constraint of dielectric constant low-frequency background information and fine description of high-frequency change characteristics are realized, so that the overall reliability and resolution capability of a dielectric constant inversion result are improved.

This invention relates to the field of coal quality testing technology, specifically to an online method and system for detecting coal quality entering the furnace; it includes: a multimodal data acquisition step: acquiring microwave scattering parameters and surface element characteristic spectra using a microwave tomography sensor array and a surface spectrometer, respectively; a physical field inversion and modeling step: reconstructing the complex permittivity distribution map based on the scattering parameters to establish a three-dimensional physical distribution model including density and moisture; a field-spectrum coupling deduction step: using the characteristic spectra as boundary constraints, and combining them with the complex permittivity distribution map to deduce the internal chemical element distribution; and a volume-weighted quantization step: performing volume-weighted integration on the three-dimensional physical model and chemical distribution to output comprehensive coal quality parameters; this invention eliminates the detection blind spots of single technologies and significantly improves the representativeness and safety of full-section detection of coal entering the furnace.

This invention relates to an intelligent flow sensing method and system for cold-pressing amorphous alloy powder, belonging to the field of flow measurement technology. The method includes constructing an acoustic emission feature vector; inputting the original capacitance measurement tensor and acoustic emission feature vector into a capacitance tomography reconstruction algorithm to construct a multi-frequency dielectric-mechanical coupled Gaussian mixture model; performing soft classification decoupling on the dielectric constant distribution matrix to generate a shear band density field and a porosity distribution field; introducing the shear band density field to perform free volume correction on the powder's apparent density distribution field, and solving to obtain a real-time flow characteristic scalar; inputting this time-series graph structure data into a graph neural network-long short-term memory coupled model; comparing the shear band network connectivity with a threshold in real time; and constructing a multi-objective cost function to achieve coordinated control of high-precision flow tracking and active suppression of shear band instability during cold pressing. This invention improves the flow sensing accuracy, instability early warning timeliness, and process control coordination of cold-pressing amorphous alloy powder.

The invention discloses a current collection cable line fault positioning and hidden danger identification method, system and device and a medium, and belongs to the technical field of current collection cable line fault analysis, and the method comprises the steps: setting a plurality of measuring points on a current collection cable line to collect fault traveling wave signals, and obtaining the traveling wave current waveform of each measuring point; acquiring dielectric constant distribution and dielectric loss factor distribution of each cable section by analyzing propagation characteristics of traveling wave current waveforms among different measuring points; taking the dielectric constant and the dielectric loss factor as two-dimensional feature vectors, and calculating an insulation degradation index of each cable section through coupling analysis; dividing a degradation section according to the numerical distribution of the insulation degradation index; determining the coordinates of a fault breakdown point according to the polarity reversal position of the traveling wave current waveform; and marking a first-level insulation hidden danger point and a second-level insulation hidden danger area. According to the method, the problem of positioning errors caused by constant wave velocity hypothesis is solved, and the fault positioning precision and the hidden danger recognition accuracy are remarkably improved.

This invention discloses a method for identifying coal and coal gangue based on capacitance tomography. It utilizes a differential capacitance tomography electrode sensor to collect capacitance measurement data of coal, coal gangue, or mixtures thereof within the measured area. Direct coupling capacitance between electrodes is canceled by applying an inverse excitation signal. The raw data is preprocessed, and stable and valid capacitance measurements are selected to form a data vector. A regularized iterative algorithm is used to solve for the dielectric constant distribution, combining a preset sensitivity distribution function. An initial solution is obtained through regularization, and then iteratively updated until convergence. Image reconstruction is performed based on the dielectric constant distribution. After normalization and edge detection, a capacitance tomography image representing the location, size, and dielectric differences of the materials is generated. The image grayscale values ​​are analyzed, and coal and coal gangue regions are automatically identified and marked according to a preset dielectric constant threshold range. Simultaneously, their centroid coordinates and equivalent areas are calculated, achieving non-destructive and accurate identification of the mixture components.

The application relates to a capacitive tomography method and system based on a two-stage neural network of physical information. The method comprises the following steps: collecting boundary capacitance measurement vector data of an imaging area under different electrode excitation modes; constructing a potential field reconstruction network as a first neural network, setting a hard boundary layer constraint in an output layer to meet a Dirichlet boundary condition, and constructing a first loss function to output a multi-channel potential field distribution of the imaging area; constructing a physical constraint inverse problem network as a second neural network, constructing a second loss function based on an electrostatic field Poisson equation and a multi-type electrode boundary condition, and inversely obtaining a preliminary dielectric constant distribution; constructing a hybrid loss function, obtaining a two-stage neural network through training, and obtaining a final dielectric constant distribution; and outputting and visualizing the final dielectric constant distribution to generate a capacitive tomography result of the imaging area, so that the imaging accuracy of capacitive tomography is improved.

The application provides a dielectric breakdown simulation method for insulating powder coating based on a phase field method, and belongs to the field of phase field method and material technology. The method comprises the following steps: constructing a dielectric breakdown phase field calculation model of the insulating powder coating, constructing a main breakdown phase field variable, constructing a relative dielectric constant distribution function changing with a spatial coordinate, and solving to obtain a total electric field intensity component; introducing a model total free energy F , introducing a unit step function to modify an Allen-Cahn equation, and obtaining a phase field control equation; determining a weak form of the phase field and electrostatic field control equation, and completing dielectric breakdown simulation through mutual coupling of the phase field and electrostatic field. The model constructed by the application can not only accurately simulate the whole process of breakdown of the insulating coating under a strong electric field, but also effectively predict a critical breakdown voltage and a possible breakdown path, thereby providing a direct and quantitative tool for precise optimization and performance improvement of the insulating powder formula.

The application relates to a kind of amorphous alloy powder cold pressure flow intelligent perception method and system, it is related to flow measurement technical field, including constructing acoustic emission feature vector;Original capacitance measurement tensor and acoustic emission feature vector are input into the reconstruction algorithm of electrical capacitance tomography, construct multi-frequency dielectric-mechanical coupling Gaussian mixture model;Soft classification decoupling is carried out to dielectric constant distribution matrix, and shear band density field and porosity distribution field are generated;Introduce shear band density field to the apparent density distribution field of the powder to carry out free volume correction, and solve to obtain real-time flow characteristic scalar;The time series graph structure data are input into graph neural network-long short-term memory coupling model;Shear band network connectivity is compared with the threshold value in real time;Multi-objective cost function is constructed, and the collaborative control of high-precision tracking of flow and active inhibition of shear band instability in cold pressing process is realized.The application improves the flow perception accuracy, instability early warning timeliness and process control synergy of amorphous alloy powder cold pressing.

The application provides a kind of sewer flow monitoring method, system and storage medium based on three-phase tomography, belongs to fluid measurement technical field.In the method, the boundary voltage vector and the capacitance vector of the radial section of the pipeline are synchronously acquired, the conductivity and dielectric constant distribution images are respectively reconstructed, and the phase distribution map is generated after fusion, according to which the cross-section content rate of gas, liquid and solid three phases is described;Based on the time sequence phase distribution map, different algorithms are used to calculate the flow rate of each phase, and the interface coupling, mass conservation and wall boundary constraint are introduced for physical correction, and finally the total flow is accurately calculated by combining the corrected flow rate, cross-section content rate and pipeline cross-sectional area.The application fuses the dual-mode information of electrical resistance and electrical capacitance tomography, realizes the independent and accurate measurement of the phase content rate and flow rate in complex multiphase flow, and has the advantages of non-invasive, no pressure loss and wide application flow type.

The invention provides a drainage pipeline flow monitoring method and system based on three-phase tomography and a storage medium, and belongs to the technical field of fluid measurement. According to the method, conductivity and dielectric constant distribution images are reconstructed respectively by synchronously obtaining boundary voltage vectors and capacitance vectors of the radial section of the pipeline, a phase distribution diagram is generated after fusion, and the section holdup of the gas phase, the liquid phase and the solid phase is described according to the phase distribution diagram; based on the time sequence phase distribution diagram, different algorithms are adopted to calculate the flow velocity of each phase, interface coupling, mass conservation and wall surface boundary constraint are introduced for physical correction, and finally the total flow is accurately calculated by combining the corrected flow velocity, the section holdup and the pipeline section area. According to the invention, resistance and capacitance tomography bimodal information is fused, independent and accurate measurement of each phase volume fraction and flow velocity in a complex multiphase flow is realized, and the method has the advantages of no invasion, no pressure loss and wide applicable flow pattern.

The application discloses an electromagnetic thermoacoustic cable detection method and device, and belongs to the technical field of cable state detection. The method applies electromagnetic excitation to the cable through an excitation source and a transmitting coil or antenna, generates ultrasonic signals under electromagnetic excitation by utilizing the difference in the conductivity and permittivity distribution in the cable medium, and detects the signals through an ultrasonic sensor or array. At the same time, the excitation current signal is detected by a current transformer, the sound source distribution and the cable electrical characteristic parameter (conductivity, permittivity) distribution are inverted, the electromagnetic signals containing cable information are collected through a receiving coil or antenna, and the electromagnetic anomalies caused by defects or aging are extracted. The reconstructed sound source image, electrical characteristic parameter image and electromagnetic anomaly signal are combined to comprehensively evaluate the cable defect and aging state. The application combines the advantages of high electromagnetic detection sensitivity and high ultrasonic imaging resolution, realizes early and accurate evaluation of the internal defects and aging state of the cable, and effectively improves the safe operation level of the cable.