140 results about "Magnetic imaging" patented technology

The invention discloses a Hall sensor combination system and method for magnetic imaging stability optimization. The system comprises a three-dimensional orthogonal Hall sensor array; the embedded encoder module is used for converting the analog magnetic field signals acquired by the sensor array into digital encoding signals with timestamps; the control module constructs an electromagnetic feature extraction model and is used for carrying out time-frequency domain conjoint analysis on the digital coding signals to obtain magnetic environment disturbance feature parameters; generating a compensation magnetic field parameter opposite to the magnetic environment disturbance characteristic parameter by adopting a closed-loop feedback mechanism; establishing a real-time data channel with a preset electromagnetic imaging module and a preset magnetic field generation module through a preset communication protocol; and constructing a magnetic environment state space model corresponding to the three-dimensional orthogonal Hall sensor array, and obtaining magnetic field distribution data to dynamically adjust and compensate magnetic field parameters so as to realize active magnetic interference cancellation in a three-dimensional space. Problems in the prior art can be effectively solved, and the precision and stability of magnetic imaging are improved.

According to the displacement modulation and optical assistance-based SERF atom magnetometer magnetic imaging method, an SERF atom magnetometer integrated with a magnetic flux guider is used as a magnetic sensor, and low-frequency magnetic field modulation is introduced to the magnetic sensor by controlling a to-be-tested sample to perform periodic infinitesimal displacement in the sensitive direction of the magnetic sensor; the modulation signal is demodulated by combining a phase-locked amplification technology, and a magnetic response signal subjected to phase-locked demodulation at each spatial position is extracted; constructing a magnetic response matrix through two-dimensional track scanning of micron-order step pitch; an image acquisition module and a reflection optical assembly are introduced for spatial registration so as to monitor the relative position in real time, and the visibility and controllability of the magnetic imaging process are guaranteed; the point-by-point detection of fT-level weak magnetic signals can be realized on the premise that an array structure is not needed; the low-frequency noise interference can be effectively inhibited, the stability and definition of direct-current and low-frequency magnetic field imaging are improved, and the method is suitable for high-resolution space imaging application of weak magnetic sources such as magnetic domain structures, nervous tissue slices and ancient rock samples.

The invention discloses a brain nuclear magnetic imaging focus reasoning method based on a multi-hop memory network. The method comprises the following steps: S1, acquiring brain nuclear magnetic resonance imaging data and corresponding clinical annotation data; s2, generating preprocessed brain nuclear magnetic resonance image data; s3, constructing a medical priori knowledge graph; s4, constructing a multi-hop memory network model; s5, generating an image feature vector; s6, generating an image feature vector fused with the prior knowledge; s7, storing the updated features in a memory unit; s8, performing hop-by-hop calibration on the judgment of the focus position, the focus range and the focus property, and outputting a focus reasoning result; and S9, performing fusion display with the original brain nuclear magnetic resonance image data. According to the method, remarkable innovation is achieved on the algorithm level, and meanwhile the accuracy and clinical applicability of the focus reasoning result are remarkably improved.

A wide-field dynamic magnetic imaging device and method. The wide-field dynamic magnetic imaging device comprises: a probe assembly (1), comprising a diamond (101) containing NV centers; a microwave magnetic field assembly (2) configured to generate a uniform microwave field and a uniform bias magnetic field in the vicinity of the diamond (101), so as to regulate the spin energy level of the diamond (101) and the quantum state evolution process; a laser modulation assembly (3) configured to output an initial uniform pulsed laser to excite the diamond (101) to emit fluorescence; a fringe light modulation assembly (4) configured to modulate the initial uniform pulsed laser to output a fringe pulsed laser, causing the fluorescence emitted by the diamond (101) to be fringe fluorescence, or to modulate the fluorescence emitted by the diamond (101) into fringe fluorescence; a fluorescence detection assembly (5) configured to perform spatial imaging on the fringe fluorescence to obtain magnetic field information of a sample under test (7), thereby obtaining an initial magnetic image of said sample (7); and a data processing assembly (6) configured to perform Fourier transform and inverse Fourier transform on the initial magnetic image to obtain a first magnetic image.

The invention provides a four-dimensional cardiac function imaging method and device based on a biological magnetic signal. The method comprises the following steps: acquiring a magnetocardiogram signal of a to-be-detected object and dynamic structure information of a target trunk part in a full cardiac cycle; wherein the target trunk part at least comprises double lungs, a trunk, a heart cavity of the trunk and a pericardium structure, and the dynamic structure information comprises a contour structure and a multi-frame dynamic image; performing spatial registration on the dynamic structure information and the sensor for acquiring the magnetocardiogram signal to obtain coordinates of the sensor in a coordinate system of the dynamic structure information; according to the dynamic structure information, the coordinate of the sensor and the magnetocardiogram signal, calculating and reconstructing cardiac electrical excitation activity to obtain a calculation and reconstruction result; and converting the calculation reconstruction result into a four-dimensional visual image. According to the method, heart magnetic imaging and heart movement are combined, on the basis of obtained dynamic structure information and heart magnetic signals, the characteristics of biological magnetic signals are fully utilized, and the signal processing technology is integrated through space registration, so that accurate reconstruction of four-dimensional representation of the heart and visual display of functional activities are realized; therefore, the obtained four-dimensional visual image can completely represent the dynamic electrophysiological activities of the whole heart (including epicardium, endocardium and intrawall tissues) in a cardiac cycle, and a technical scheme with different concepts is provided for non-invasive imaging of cardiac electrical excitation activities.

The invention discloses an SERF atom magnetometer double-axis magnetic field detection method and device based on pulsed magnetic field modulation, relates to the technical field of magnetic field precision measurement, and compresses the action time of a modulation magnetic field additionally applied in the same unit period on a hot atom ensemble by replacing conventional continuous sinusoidal magnetic field modulation with pulsed magnetic field modulation. The pulse magnetic field with the duty ratio of d can reduce the spin exchange relaxation rate to 2d times of that of a conventional method under the same modulation amplitude and frequency, due to the fact that the spin exchange relaxation rate is effectively restrained, the collected polarizability response signal is obviously improved, and the polarizability response signal can be obtained through the pulse magnetic field with the duty ratio of d and the pulse magnetic field with the duty ratio of d. Low-relaxation-rate sensitivity-enhanced double-axis magnetic field measurement under a pulse modulation scheme is realized, the double-axis measurement sensitivity of a miniaturized SERF atom magnetometer is further improved, and the method has great significance in supporting leap-type development of a future array type extremely-weak magnetic imaging system and medical application thereof.

A lithium battery detection device based on BB optical pump magnetic imaging comprises a magnetic shielding cylinder and a substrate arranged in the magnetic shielding cylinder, and a laser, an optical lens system, an atomic gas chamber system, an array lens and an array photoelectric detector are sequentially arranged on the working face of the substrate from left to right; the atomic gas chamber system contains alkali metal atoms and buffer gas; a non-magnetic objective table for placing a lithium battery to be tested is arranged above the atomic gas chamber; according to the device, the array lens is adopted to split and focus a single beam of detection laser into small light spots which are respectively irradiated on different photoelectric detectors, and magnetic field information of a plurality of space point locations is detected at one time, so that the consistency and imaging quality of a subsystem are improved, and the system cost is saved.

The invention discloses an ultrahigh-sensitivity three-axis closed-loop spin exchange relaxation-free atom magnetometer, which expands the ultrahigh-sensitivity measurement capability of the atom magnetometer to three axes based on parameter modulation optimization and double detection light, fully inhibits transverse spin relaxation introduced by a modulation magnetic field, provides more high-quality information for weak magnetic measurement, and improves the measurement accuracy. Based on decoupled magnetic field information, a three-axis magnetic field sensitive to an atomic ensemble is locked to zero in real time, and closed-loop feedback quantity is used as magnetic field measurement information, so that the problems of nonlinear offset of a magnetometer calibration coefficient and cross-axis coupling crosstalk caused by magnetic field drift are fundamentally inhibited; the high anti-interference capability of the atom magnetometer in a complex magnetic field environment is enhanced, long-time stable measurement and magnetic field measurement precision of the atom magnetometer are guaranteed, sub-fT-level sensitivity and pT-level precision can be achieved on transverse double axes, and the atom magnetometer is suitable for the fields of extremely weak magnetic measurement testing, biomedical weak magnetic imaging and the like.

The invention provides a CBCT pseudo nuclear magnetic image reconstruction method based on artificial intelligence, and relates to the field of pseudo nuclear magnetic image.The method comprises the steps that multi-modal image data and text description corresponding to the image are obtained, a paired data set and a non-paired data set are constructed, preprocessing is carried out, and a preprocessed multi-modal data set is obtained; carrying out integration by using a stable diffusion model, and carrying out multi-modal pre-training and cross-modal fine tuning to obtain a trained multi-modal generative basic model; constructing a deep learning model based on the converter, combining with a dual attention strategy, and training by using non-paired data to obtain a trained structure guide converter; and cascading the trained model and a structure guide converter, performing synchronous optimization through multi-task learning, dynamically adjusting the weight of a loss function, and generating a pseudo nuclear magnetic image by using a joint model based on real-time acquisition of CBCT data. The method and the device are used for overcoming the defects of scarcity of paired data and insufficient utilization of non-paired data in the prior art.

Techniques are described for determining cognitive impairment, an example of which includes accessing a set of epochs of magnetoencephalography (MEG) data of responses of a brain of a test patient to a plurality of auditory stimulus events; processing the set of epochs to identify parameter values one or more of which is based on information from the individual epochs without averaging or otherwise collapsing the epoch data. The parameter values are input into a model that is trained based on the parameters to determine whether the test patient is cognitively impaired.

The invention discloses a visual tactile sensor based on a magnetic imaging principle. The visual tactile sensor comprises a shell, an image acquisition module, a magnetic pole display film, an elastic body and a magnetic film, the magnetic pole display film, the elastic body and the magnetic thin film are arranged in the shell from top to bottom, and the image acquisition module is located above the magnetic pole display film and used for acquiring an image of the magnetic pole display film; when the sensor is used for pressure sensing, the position with the maximum gray level variation of the magnetic pole display film image is the pressure acting position, and the pressure is equal to the result that the gray level variation of the magnetic pole display film image is divided by the magneto-optical conversion coefficient of the magnetic pole display film and the product thereof. The magnetic induction intensity in the center range of the surface of the magnetic film, the initial distance between the magnetic film and the magnetic pole display film and the equivalent elastic coefficient of the magnetic film and the elastic body are related. The sensor converts a mechanical signal into a magnetic field signal and then converts the magnetic field signal into an optical image, high-sensitivity sensing of tiny pressure is achieved, and meanwhile the sensor has the higher signal-to-noise ratio, stability and anti-interference capacity.

For interventional surgery, robot-assisted operation and image guidance are urgently required clinically. However, due to limitation of size, magnetic component interference and the like, tracking and positioning of magnetic imaging catheters in IVUS and OCT forms are difficult problems. The interventional imaging catheter, the six-degree-of-freedom positioning method, the six-degree-of-freedom positioning system, the six-degree-of-freedom positioning equipment and the medium are different from a magnetic positioning method of a transmission embedded sensor, and the interventional imaging catheter is compatible with a magnetic part in a permanent magnet rotor form. Meanwhile, in cooperation with a magnetic positioning search strategy for linearly solving an initial value, positioning of the catheter can be rapidly achieved.

According to the structure for reducing the area of the SQUID superconducting loop and the preparation method thereof provided by the invention, the laminated structure is formed on the silicon substrate, and then the laminated structure is accurately etched, so that the 3D nano bridge junction is formed on the slope surface of the laminated structure and stretches across the insulating layer, and therefore, batch preparation of the structure for reducing the area of the SQUID superconducting loop can be realized; according to the SQUID probe, large-scale application of the SQUID probe is more facilitated, the plane of the 3D nanometer bridge junction is perpendicular to the plane where the SQUID superconducting loop is located, so that the width of the 3D nanometer bridge junction does not influence the effective loop area of the SQUID any more, the performance of the SQUID can be improved by independently regulating and controlling the thickness of the 3D nanometer bridge junction, the inhibition effect of a magnetic field on the superconducting characteristic of the 3D nanometer bridge junction is greatly weakened, and in addition, the SQUID probe can be applied to a large scale. The SQUID superconducting loop with the minimum line width of 10nm can be prepared by combining the electron beam lithography technology with higher precision, the area of the SQUID superconducting loop can be greatly reduced, and the spin sensitivity is improved, so that higher spatial resolution can be realized during scanning magnetic imaging.

A coil for single-sided magnetic resonance imaging is disclosed. The coil is configured to generate a magnetic field outwards away from the coil. The coil includes a first ring and a second ring having different diameters and the current flows through the coil to generate the magnetic field in a region of interest. A method of imaging via a magnetic imaging apparatus is also disclosed. The method includes providing a power source and providing a coil that includes a first ring and a second ring having different diameters. The method includes turning on the power source so as to flow a current through the coil to generate a magnetic field in a region of interest. The method also includes selectively turning on a particular set of electronic components so as to pulse the magnetic field in a narrower frequency range.

The invention relates to the technical field of magnetic field measurement error compensation, in particular to a single-axis Hall surface magnetic rapid imaging analysis system, which is characterized in that a magnetic field gradient real-time analysis unit calculates a magnetic field gradient change rate through a sliding window weighted difference algorithm, identifies a magnetic pole transition region and analyzes the magnetic field gradient change rate. The multi-source error coupling modeling unit synchronizes Hall probe spacing fluctuation, inclination angle and magnetic field gradient data and constructs a composite compensation function, the adaptive compensation unit corrects and counteracts spacing attenuation and projection errors through two-stage assembly lines, and the nonlinear trigger control unit generates an adaptive encryption trigger signal, so that the sampling spacing decreases progressively along with the gradient change rate, and the error compensation is realized. And the magnetic field distribution reconstruction unit fuses the compensation data and the sampling sequence, reconstructs a continuous magnetic field distribution curve by adopting gradient constraint cubic spline interpolation, accurately outputs a magnetic pole boundary position and a surface magnetic field intensity quantification result, and improves the surface magnetic imaging precision and efficiency.

The invention discloses an overlying strata fracture electromagnetic imaging method and a grouting system, and particularly relates to the technical field of geological fracture imaging. The invention discloses an overlying strata fissure electromagnetic imaging method and a grouting system. The method comprises the steps that S1, magnetic source slurry containing permanent magnetic material particles is injected into a target overlying strata fissure area through the grouting system; s2, magnetizing the magnetic source slurry injected into the crack through an electromagnetic coil group arranged on the grouting system; s3, tracer slurry containing magnetic responsive nanoparticles is injected into the fissure area where the guiding magnetic field is formed through a grouting system; s4, in-hole electromagnetic detection equipment is adopted to scan the fracture area filled with the tracing slurry, and electromagnetic response data are obtained; and S5, processing and analyzing the electromagnetic response data. According to the overlying strata fissure electromagnetic imaging method and the grouting system provided by the invention, through a technical path of'pilot magnetism and post tracing ', the tracing slurry is actively guided to directionally migrate by utilizing the magnetic field, and high-precision filling and electromagnetic imaging of an overlying strata fissure network are realized.

The invention discloses a tumor prognosis prediction system based on a multi-sequence nuclear magnetic imaging, and relates to the technical field of tumor prognosis prediction. According to the invention, through the single-mode tumor and peritumoral feature multi-graph fusion module, the whole tumor is taken as a global feature, the peritumoral region is subjected to local feature and global guidance local feature fusion is carried out, so that introduction of excessive redundant features can be avoided, and heterogeneity features of the tumor and the peritumoral region can be fully utilized, so that the interpretability of the model is improved; according to the method, multi-modal spatial features are divided into two-order neighbor nodes through a multi-modal feature spatial topology slice fusion module, a public learnable feature vector is introduced, a multi-modal spatial topology relation is learned, the multi-modal features are utilized more effectively, and the accuracy of model prediction is improved; through the interval consistency control module and the KL divergence and interval consistency joint loss function, the consistency of the multi-sequence nuclear magnetic image feature expression ability is controlled, overfitting of the model can be avoided, and the generalization ability of the model is improved.

Systems and methods directed toward acoustic analysis can include a plurality of acoustic sensor arrays, each including a plurality of acoustic sensor elements, and a processor in communication with the plurality of acoustic sensor arrays. The processor can be configured to select one or more of the plurality of acoustic sensor arrays based on one or more input parameters, and generate acoustic image data representative of an acoustic scene based on received acoustic data from the selected one or more acoustic sensor arrays. Such input parameters can include distance information and / or frequency information. Different acoustic sensor arrays can share acoustic sensor elements in common or can be entirely separate from one another. Acoustic image data can be combined with electromagnetic image data from an electromagnetic imaging tool to generate a display image.

In embodiments, a method for configuring an intelligent agent to do a task based on spatial-temporal magnetic imaging data of the brain of a worker is disclosed. The method includes generating a brain region parameter indicating an active neocortex region associated with visual processing during performance of the task based on the spatial-temporal magnetic imaging data. The method further includes selecting a convolutional neural network (CNN) component type in response to a match between the brain region parameter and an associated CNN component type. The method includes configuring the intelligent agent based on the selected CNN component and a neocortical processing flow parameter derived using the spatial-temporal magnetic imaging data, wherein the intelligent agent is configured to process image data using the CNN component and provide an output of the CNN to another AI component via a data connection created based on the neocortical processing flow parameter.

The invention discloses a super-surface sub-terahertz inversion imaging method and system, and relates to the field of multi-dimensional electromagnetic imaging. The problems of view field mismatching, output delay, large-size imaging and the like existing in a directional aperture sharing TR framework of an existing APCI based on the metasurface are solved, synchronous extraction of sub-terahertz frequency band active scattering and passive radiation data is achieved through spatial staggered layout and related average processing technologies, and the system has the advantages that the system is simple in structure and convenient to operate, and the system is easy to popularize and use. And a solution is provided for single-region information decoupling and multi-target fusion imaging. The highly integrated and high-throughput sub-terahertz APCI technology promotes the development of the detection system towards the direction of miniaturized deployment and real-time data reading. Besides, a non-imaging security check scheme is also introduced, non-interactive autonomous identification and hidden monitoring of hidden objects in public scenes are realized, and the method is also suitable for the application fields of aircraft navigation positioning, abnormity monitoring, non-interactive hidden security check and the like.

The invention discloses an electric transport measuring device and method, and the device comprises a probe structure which comprises a sample stage, a quantum probe assembly and an optical assembly, the sample stage is used for placing a to-be-measured sample, and an electric transport measuring condition is applied to the to-be-measured sample, so as to obtain an electric transport measuring signal; the quantum probe assembly is provided with a tuning fork and a piezoelectric crystal. The free end of the tuning fork is provided with an NV probe. The optical assembly emits exciting light, the exciting light is focused to the NV probe, microwave radiation is applied to the NV probe, and a fluorescence signal emitted by the NV probe is collected; the device also includes a control module for performing performance analysis based on the fluorescence signal and the electrical transport measurement signal. The electric transport measurement condition is applied to the to-be-measured sample through the sample table so as to obtain the electric transport measurement signal, and the electric transport characteristic is represented by monitoring the magnetic signal in combination with the quantum scanning magnetic imaging technology, so that the injection and extraction difficulty of local microscopic charges is reduced, and the measurement efficiency is improved.

The embodiment of the invention discloses a method and device for testing foam seepage characteristics of a heterogeneous porous medium, electronic equipment and a storage medium, and relates to the technical field of fluid mechanics and nuclear magnetic resonance. The method comprises the steps that a heterogeneous porous medium sample with a clear permeability level difference is prepared, and the permeability level difference of the heterogeneous porous medium sample is determined; setting test parameters according to the permeability level difference of the sample, calibrating imaging parameters of the low-field nuclear magnetic resonance equipment, and setting a weighting mode; performing foam flooding treatment on the sample according to the set injection parameters, acquiring a spectrum of the sample according to the test parameters when foam is injected into a set amount, and acquiring nuclear magnetic imaging of the sample through low-field nuclear magnetic resonance equipment according to imaging parameters and a weighting mode; according to the relaxation characteristic of the spectrum, the main peak endpoint value is used for dividing the pore channel, the foam sweep degree is calculated according to the spectrum peak area of the spectrum, and the foam plugging strength is calculated according to the signal amplitude of nuclear magnetic imaging. According to the method, the problems of poor visualization adaptability and lack of evaluation systems in the prior art are solved.

A surgical frame incorporating an electromagnetic-radiation imaging device, and a radiation-mitigation system for use with the surgical frame are provided. The surgical frame can be capable of reconfiguration before, during, or after surgery, and can include a main beam that can be rotated, raised / lowered, and tilted upwardly / downwardly to afford positioning and repositioning of a patient supported thereon. The surgical frame can support the electromagnetic-radiation imaging device. One of an emitter and a receiver of the electromagnetic-radiation imaging device can be positioned under the main beam of the surgical frame, and the other of the emitter and the receiver of the electromagnetic-radiation imaging device can be positioned over the main beam of the surgical frame. The radiation-mitigation system can serve to intercept / block and mitigate at least some of the scatter of the electromagnetic radiation from the emitter.

Various embodiments disclosed herein comprise systems and methods to conform magnetic field sensors to a target geometry. In some examples, an apparatus is configured to conform to a target geometry. The apparatus comprises a sensor mount and a sensor array. The sensor mount comprises a flexible state for a first environmental condition and a rigid state for a second environmental condition. The sensor mount transitions from the flexible state to the rigid state when the first environmental condition transitions to the second environmental condition. The sensor mount transitions from the rigid state to the flexible state when the second environmental condition transitions to the first environmental condition. The sensor array is coupled to the sensor mount.

The present disclosure provides a wide-field dynamic magnetic imaging device and method, which includes: a probe assembly including a diamond containing NV color centers; a microwave magnetic field assembly adapted to generate a uniform microwave field and a uniform bias magnetic field near the diamond to regulate the spin energy level and quantum state evolution process of the diamond; a laser modulation assembly adapted to output an initial uniform pulse laser to excite the diamond to emit fluorescence; a stripe light modulation assembly adapted to modulate the initial uniform pulse laser to output a stripe pulse laser so that the fluorescence emitted by the diamond is stripe fluorescence; or to modulate the fluorescence emitted by the diamond into stripe fluorescence; a fluorescence detection assembly adapted to perform spatial imaging of the stripe fluorescence to obtain magnetic field information of a sample to be tested, thereby obtaining an initial magnetic image of the sample to be tested; and a data processing assembly adapted to perform Fourier transform and inverse Fourier transform processing on the initial magnetic image to obtain a first magnetic image.

In one embodiment, a method implemented by an electromagnetic imaging system for imaging material within a metal container, the method comprising: transmitting to. and receiving signals from, a plurality of antennas attached to an interior wall of the metal container, the signals delivered over a plurality of channels, each of the plurality of antennas comprising a ferrite loaded, shielded half-loop antenna; measuring a plurality of scattering parameters (S-parameters) for all of the plurality of channels; calibrating the measurements; and providing an image of the material using an inversion algorithm based on the calibrated measurements.

This invention provides a CT and SERF-based magnetic resonance imaging (MRI) registration system and method, including a MRI registration module and a CT registration module. The MRI registration module includes a multi-turn circular positioning coil and an adjustable patch limiting device; the positioning coil can be fixed to a protrusion of the limiting device. The CT registration module includes a non-magnetic marker with an appearance consistent with the arc-shaped reference object of the MRI registration module. CT scans acquire the image structure of the human torso, perform segmentation and 3D reconstruction; the relative positional relationship between the human body and the magnetometer can be obtained based on the positioning coil. The arc-shaped reference objects of the MRI registration module and the CT registration module are registered using a nearest neighbor algorithm, thereby completing the conversion between the CT coordinate system and the magnetometer coordinate system. This system is unaffected by human respiration, improving registration accuracy, making MRI equipment more complete, and advancing subsequent 3D imaging applications.

The invention discloses an anomalous body positioning method and system combining borehole transient electromagnetic and geological radar, and relates to the technical field of mine safety detection, and the method comprises the steps: synchronously collecting the borehole transient electromagnetic data and geological radar data of an ore body to be analyzed, and generating a borehole transient electromagnetic imaging graph and a borehole geological radar imaging graph; two-dimensional coordinates of a target abnormal point in the borehole geological radar imaging graph are extracted, and the corresponding target apparent resistivity is determined; drawing an apparent resistivity contour map based on the target apparent resistivity in a target radial sectioning map of the borehole transient electromagnetic imaging map, and determining a plurality of candidate three-dimensional coordinates of a target abnormal point; at least one target feature point is selected from the borehole geological radar imaging graph, and the feature apparent resistivity corresponding to the target feature point is determined; and drawing a feature circle based on the target feature points, and screening the plurality of candidate three-dimensional coordinates to obtain coordinates of the geological anomalous body. According to the invention, the technical problem of insufficient positioning precision and reliability in the prior art is solved.

The application provides an underwater rock mass crack positioning and repairing method based on acoustic emission and electromagnetic fusion, acquires acoustic emission signals of underwater rock mass through an acoustic emission monitoring module, extracts acoustic emission features, and determines a crack area based on a time difference positioning algorithm; applies current excitation in the crack area through an electromagnetic imaging module, and acquires potential responses through an electrode array; establishes an electromagnetic field inverse problem model based on the potential responses, and obtains a conductivity characteristic parameter; determines a crack grade based on the acoustic emission features and the conductivity characteristic parameter, and generates a repairing instruction when the crack grade exceeds a preset threshold; and performs reinforcement work in the crack area according to the repairing instruction. Multiple modules complement each other, reduce misjudgment and missed detection, and improve the reliability and resolution of crack identification.

In one embodiment, a system comprising: a container configured to store commodity; a measurement system comprising a vector network analyzer (VNA), a switch module, a plurality of cables, the container, and a plurality of antennas coupled to interior walls of the container, the switch module configured to switch signals transmitted to and received from the plurality of antennas via a plurality of channels, the VNA configured to measure scattering parameters (S-parameters) of all of the plurality of channels; a non-transitory computer readable medium comprising software; and a processor configured by the software to: de-embed a combined effect of the measurement system based on a 2-port network de-embedding technique using only a subset of the S-parameters; and provide an image of the commodity using an inversion algorithm based on input of a calibrated S-parameter after the de-embedding.