59 results about "Electromagnetism" patented technology

The invention provides an electromagnetic field prediction method and device and electronic equipment, and relates to the technical field of electromagnetic field solving. The method comprises the following steps: acquiring historical electromagnetic original data in a field-line coupling scene, preprocessing the historical electromagnetic original data, inputting the preprocessed historical electromagnetic original data into an LSTM-PINN model, and outputting a physical field quantity mapping result; wherein the physical field quantity comprises an electric field component and a magnetic field component; setting a weighted loss function, and performing optimization training on the LSTM-PINN model based on a physical field quantity mapping result and an error of a real physical field quantity corresponding to historical electromagnetic original data to obtain a trained electromagnetic field prediction model; wherein the weighted loss function comprises a data loss function, a physical residual loss function, an initial condition loss function and a boundary condition loss function; and inputting real-time electromagnetic original data into the trained electromagnetic field prediction model to obtain a spatio-temporal distribution electromagnetic field prediction result. The method can effectively extract the spatial distribution features and the time sequence features at the same time, and is suitable for a complex field-line coupling problem.

The invention belongs to the technical field of geological engineering monitoring and multi-physics field intelligent sensing, and discloses a separation grouting slurry migration monitoring method and system, and the method comprises the steps: constructing an acoustics-optics-electricity-electromagnetism multi-physics field coupling monitoring system; a grouting hole and a monitoring drilling hole array are arranged in a target stratum, a distributed optical fiber sensor, a drilling hole ultrasonic imager, a resistivity measuring device and a transient electromagnetic detection device are installed, and a three-dimensional monitoring network is formed; synchronously acquiring sound field, light field, electric field and magnetic field data; four-field monitoring data and overlying strata multi-parameter observation data are fused, a coal seam mining three-dimensional overlying strata separation model is constructed, and a slurry diffusion three-dimensional visualization model is generated through numerical simulation; and based on the four-field monitoring response difference of the separation space before and after grouting, in combination with a monitoring frequency domain correction model of multiple indexes of grout diffusion, the diffusion range, compactness and filling effect of the grouting grout are evaluated, and abnormal early warning is triggered.

The invention discloses a microwave device multi-physics field optimization method taking electromagnetism as a center based on a feature assistance and proxy model. The method comprises the steps of setting initial values of geometric design variables and multi-physics field design variables; the multi-physical field response with electromagnetism as the core responds at the solution point {xg, xm}, multiple pieces of parallel multi-physical field data are generated, and f represents the frequency; according to the multi-physics field data, constructing a feature-assisted multi-physics field agent model based on a neural network transfer function, and calculating a gradient optimization derivative of the feature-assisted multi-physics field agent model; and on the basis of the gradient optimization derivative and the optimization feature auxiliary multi-physics field agent model, obtaining an optimal solution of the variable. According to the method, the robustness and optimization design efficiency of a microwave device multi-physics field optimization algorithm taking electromagnetism as a core are improved.

The present disclosure provides systems and methods for detecting and mapping a subsurface object. The system includes a set of transmitters configured to emit a primary electromagnetic field, a set of receivers spatially separated from the transmitter and configured to detect a secondary magnetic field generated by the subsurface object in response to the primary electromagnetic field, and a processor operably connected to the transmitter and the receivers. The processor is configured to control the transmitter to generate the primary electromagnetic field, generate a data signal based on the secondary magnetic field detected by the receivers, and analyze the data signal to determine characteristics of the subsurface object based on the processed signal.

The invention discloses a pyrolytic particle detection device, which relates to the technical field of fire detection and comprises an air pump, a heating cavity, a conducting electromagnetic valve, a refrigeration cavity, a laser detection cavity, an exhaust electromagnetic valve, a weak photoelectric pulse signal processing unit, a comprehensive control and data processing unit and an RS485 communication unit. The sucking pump, the heating cavity, the conduction electromagnetic valve, the refrigeration cavity, the laser detection cavity and the exhaust electromagnetic valve are sequentially connected through 8 mm silica gel air pipes to form a complete air path system; the invention provides a pyrolytic particle detection device which can accurately detect pyrolytic particles in air in real time, can digitally display the content of the detected pyrolytic particles, can avoid interference of environmental factors such as dust, water mist, strong light and electromagnetism, and provides an effective detection device for extremely early warning of a fire hazard. And sufficient favorable time for several hours is provided to control combustion conditions, so that event expansion is avoided.

The invention relates to the technical field of electromagnetism and magnetic material loss prediction, in particular to a magnetic core loss prediction method based on an empirical state space model, which combines magnetic flux density (Bt) and magnetic field intensity (Ht) with temperature and frequency as key physical variables and incorporates the key physical variables into a neural network model. According to the method, the input feature space of the model is widened, the cross coupling effect between variables is considered in a larger range, the model can show high predictive capacity under different materials and working conditions, and the applicability in various environments is improved; aiming at various physical effects possibly existing in the magnetic material loss process, a plurality of parallel neural network modules are designed by introducing multi-state attribute constraints and considering mutual coupling and constraint effects of the multi-state attribute constraints, so that the superimposed effect of magnetic core loss is simulated, and the limitation of a traditional single formula model is broken through; and the complex change rule of the magnetic core loss is reflected more comprehensively, so that the expression capability of the model under various working conditions is effectively improved.

The utility model discloses an electromagnetic pulse air pressure spray water gun, which relates to the technical field of fire extinguishing devices and comprises an electromagnetic pulse spray water gun body, an internal structure and an external structure, the internal structure is fixedly connected inside the electromagnetic pulse spray water gun body, and the external structure is fixedly connected outside the electromagnetic pulse spray water gun body. The reciprocating piston slides on the surface of the connecting guide rod at a high speed under the action of magnetic force of the transmitting coil, the reciprocating piston moves to push out a fire extinguishing agent in the water storage chamber from an opening shaped like a Chinese character'mi 'in the surface of the rubber front baffle for extinguishing fire, and the electromagnetic pulse spraying water gun body takes electromagnetism as a power source which is much better than high-pressure gas; the electromagnetic pulse spraying water gun is lighter than a pulse air pressure spraying water gun, the electromagnetic pulse spraying water gun body is more convenient and flexible in maneuverability, a standby power supply is much lighter than a standby air cylinder, and the size is much smaller.

The application provides a method for calculating interface polarization charge and current distribution based on reflection coefficient, and relates to the technical field of computational electromagnetics. The method comprises the following steps: establishing a reflection coefficient-dielectric parameter mapping, directly correlating the reflection characteristics of electromagnetic waves with the intrinsic parameters of the medium through a reflection coefficient formula, and laying a physical foundation for polarization analysis; interface electromagnetic field reconstruction, using boundary conditions and constitutive relations to determine the electric field distribution on both sides of the interface and the corresponding polarization intensity. The distribution rule of the electromagnetic field in the medium is determined, the macroscopic electric field is converted into the spatial description of the polarization intensity, and an intermediate variable is provided for charge and current calculation; polarization dynamic response quantification, through the spatial and temporal derivatives of the polarization intensity, the interface polarization charge density and the polarization current density are derived. The theoretical model is converted into actual physical quantities, and the dynamic response mechanism of charges and currents when electromagnetic waves interact with the medium is revealed.

Various Freight left hand rules (motor rules), right hand rules (engine rules), Ampere rules 1, Ampere rules 2 (right hand spiral rules), Lorentz forces, Ampere forces and the like exist in the fields of electrotechnics, electromagnetics, optics and the like and are used for judging current, magnetic fields and acting force directions. And memory disorder of students and technicians is easily caused. The electronic magnetic pole and the spinning direction (figure 1 in the specification) are marked by using an electronic spinning right-hand rule expression method, and all the rules and forces can be replaced and unified. And three breakthrough discoveries are caused: (1) an electron magnetic pole and a spinning direction rule are caused; and (2) the electromagnetic field is the expansion, static and retraction type expression of the electronic ring. And (3) the expansion type electronic ring has the characteristics of electromagnetic wave (including light wave) particles, fluctuation, electromagnetism, quantum and the like, and solves the optical hundred-year competition problem. And more electronic equipment and products can be developed according to the'electron spin right hand rule '.

The utility model relates to an electromagnetic field fresh-keeping cabinet, which belongs to the field of fresh-keeping cabinets and comprises a refrigerating box. The mounting assembly is arranged on the upper surface of the refrigeration box in a communicating manner; the electromagnetic mechanism is arranged on the inner side of the mounting assembly; the loading assembly is detachably arranged on the inner side of the mounting assembly and comprises a loading box which is detachably arranged on the inner side of the mounting assembly; the two connecting plates are respectively arranged on the left side and the right side of the charging box; and the two handles are respectively arranged on the upper surfaces of the two connecting plates. According to the electromagnetic field fresh-keeping cabinet, electromagnetism in the fresh-keeping cabinet can be monitored through the arranged electromagnetic mechanism, so that the use safety of the electromagnetic field fresh-keeping cabinet is guaranteed, meanwhile, under the action of the loading assembly, meat food can be rapidly taken out of the mounting box, and therefore workers can rapidly clean the interior of the mounting box; and under the action of a shielding plate, electromagnetism can be blocked, so that the use safety of the electromagnetic field fresh-keeping cabinet is improved.

The application discloses a magnetic moment comparator device and a measuring method. The magnetic moment of a current-carrying standard coil is proportional to the magnetic field generated at a fixed distance on the axis, and according to the principle of equivalence between the magnetic dipole layer and the current-carrying coil in electromagnetism, the magnetic moment of the magnetic sample at the same position can be measured by the current-carrying standard coil when the spatial magnetic field can be accurately measured. The application designs a magnetic moment comparator in a magnetic shielding cylinder, uses an atomic magnetometer to measure the absolute magnetic field with high sensitivity, places a current-carrying standard coil at a distance r0 on one side of the atomic chamber along the background magnetic field direction, and the axis is parallel to the background magnetic field direction; the magnetic moment direction of the magnetic sample is parallel to the background magnetic field direction, when the magnetic sample is moved to the position of the atomic chamber at a distance r0 on the other side of the atomic chamber by a sample transmission rod, the current flowing into the standard coil is changed in real time under the condition that the background magnetic field remains unchanged, and then the magnetic moment of the magnetic sample is equal in size and opposite in direction to the magnetic moment of the current-carrying standard coil.

The anti-magnetic cable comprises a cable core, the side surface of the cable core is fixedly connected with an insulating layer, the side surface of the insulating layer is fixedly connected with an anti-magnetic layer, and the side surface of the anti-magnetic layer is fixedly connected with an outer sheath; the side surface of the magnetic ring is fixedly connected with a connecting rod, the side surface of the connecting rod is in threaded connection with an extension rod, the end, away from the connecting rod, of the extension rod is rotationally connected with a rotating block, the inner side face of the rotating block is in threaded connection with a threaded rod, and one end of the threaded rod is fixedly connected with a connecting block. Through the components, the antimagnetic layer can be used for isolating electromagnetism, converting electromagnetic radiation into heat and improving the anti-interference effect, the insulating layer with good heat insulation performance is used for protecting the internal cable core, the heat generated by the antimagnetic layer is effectively isolated, the influence on the cable core is avoided, the magnetic ring can be used for inhibiting electromagnetic interference, and the anti-interference effect is improved. And the extendable extension rod is arranged between the two groups of magnetic rings, so that a certain distance is kept between the cables, and mutual interference is prevented.

The invention discloses a low-frequency interference magnetic field elimination method and system, and belongs to the technical field of electromagnetism and control. The device mainly comprises a magnetic sensor module used for collecting interference magnetic field signals, a conversion circuit module used for converting the interference magnetic field signals into analog voltage signals, a characteristic frequency band interference signal selection module, an analog signal phase adjustment module, a multi-path characteristic frequency band interference signal addition module, an output gain adjustable module and a power amplification module. A magnetic field generation module and an elimination effect detection feedback module. According to the low-frequency interference magnetic field elimination system, an analog circuit design method is adopted, low-frequency interference magnetic fields of several different frequency bands can be effectively weakened and eliminated, and the low-frequency interference resistance of devices with high low-frequency interference sensitivity such as ultralow-field magnetic resonance imaging equipment can be improved by adjusting system related parameters; and the equipment availability is enhanced.

The utility model discloses a magnetoresistive sensor with a conductive slip ring and a measurement experiment instrument of a geomagnetic field, which comprises a fixed working plate with an angle, a limiting ring is fixed on the lower wall surface of the working plate, a locking nut is arranged on the limiting ring, a fastening jackscrew is arranged on the locking nut, a ring groove is arranged on the working plate, and the conductive slip ring is arranged in the ring groove. A ring groove is formed in the working plate, a rotating steel ball is installed in the ring groove, a coil rotating table is installed in the working plate, and the coil rotating table is in lap joint with the rotating steel ball. A magnetoresistive sensor with a conductive slip ring and an experimental instrument for measuring a geomagnetic field are suitable for one of experimental instruments for measuring a weak magnetic field in an electromagnetic physical experiment of higher hospital science, and a precise angle measuring device of the instrument adopts the conductive slip ring, so that the instrument can rotate by 360 degrees without hindrance during angle measurement, and a measuring wire is not cut off; and the measurement is more convenient.

The utility model discloses a miniaturized high isolation degree coupler relates to the field of coupler, including the casing and the magnetic core, the lateral wall of casing adopts recessed structure to set up, the magnetic core sets up at the recessed position department of casing's lateral wall, the lateral wall of casing and be located the recessed position department is equipped with the protection isolation cover that will the magnetic core block, the protection isolation cover includes the upper cover body and lower cover body of magnetic adsorption setting, the inside of upper cover body and the inside of lower cover body all are equipped with the shielding layer. The utility model discloses have high isolation degree structure, avoid the interference that the outside world's electromagnetism causes to the magnetic core, avoid signal crosstalk and the phenomenon of error code simultaneously, thereby make the coupler can be accurately detected, in addition, have good heat conduction performance, improve the stability of coupler use.

The invention relates to the cross technical field of computational electromagnetism and precision permanent magnet device design, in particular to a method for improving the nonuniformity of a magnetic disk space magnetic field, and aims to solve the problems that a method for improving the uniformity of a magnetic field in the prior art is low in optimization efficiency and difficult to break through the uniformity bottleneck caused by angular harmonic waves and a structural coupling effect. According to the scheme, the method comprises the steps that an accurate finite element model containing seven circles of fan-shaped magnets, a parallel magnetic disk, an eddy current disk and an iron support is established in Opera3D, and meshing and solving are carried out; in the first stage, the structural height of the iron stand is optimized through parameterized scanning, and the optimal height parameter is determined; and in the second stage, on the basis of the optimal iron stand height, the outermost two circles of the magnetic disk are set as NdFeB. The non-uniformity deviation (delta B) of the magnetic field of the target spherical area can be reduced by 13%, and the method is suitable for high-precision scenes such as nuclear magnetic resonance and synchrotron radiation light sources and has the advantages of being efficient in design and high in repeatability.

The invention discloses a nano-molecular device magnetic response modeling method and system based on machine learning, and relates to the technical field of electromagnetis.The system comprises an electromagnetic response testing module, an electromagnetic response modeling module and a parameter adjusting module; the electromagnetic response test module is used for detecting the current and voltage oscillation frequency between a reference magnetic layer and a free magnetic layer of the nano oscillator and detecting the external magnetic field intensity of the nano oscillator; the electromagnetic response modeling module is used for predicting the precession frequency deviation state of a free magnetic layer under current regulation by using a machine learning method, and predicting the voltage oscillation frequency change of the nano oscillator when the external magnetic field intensity changes; the parameter adjusting module is used for adjusting direct current spin polarization current and external magnetic field intensity, the electromagnetic response test module comprises a conductive electrode, a current detection unit, a voltage detection unit and a spectrum analysis module, and the device has the advantage of being efficient in adjustment.

The invention belongs to the technical field of electromagnetism experiment teaching instruments, and particularly relates to a demonstration experiment device and method for verifying the Biot-Savart law. The device is reasonable in design, the geomagnetic field serves as a reference magnetic field, indirect measurement of the magnetic induction intensity around the current-carrying wire is achieved by measuring the deflection angle of the magnetic needle under the action of the current-carrying wire according to the vector superposition principle of the magnetic field, a traditional measurement mode depending on a Hall sensor or a fluxmeter is replaced, and the measurement accuracy is improved. A measurement basis is provided for a verification experiment of the Biot-Savart law; the device is structurally composed of an angle positioning bottom plate, a current-carrying wire assembly and a magnetic needle measuring assembly, the relative magnetic induction intensity is obtained through visual angle reading, and data calculation is achieved in combination with the magnetic field vector superposition relation. By measuring the relationship between the magnetic induction intensity on the symmetry axis of the current-carrying bent conductor and the vertical distance, the current magnitude and the bending angle, experimental verification demonstration of the Biot-Savart law is realized.

The invention relates to the technical field of coal mine safety mining and roof disaster prevention and control, and discloses a roof directional long drill hole hydraulic fracturing multi-parameter effect discrimination method, which comprises the following steps of: firstly, constructing a multi-element heterogeneous integrated comprehensive discrimination system, and arranging micro-seismic, transient electromagnetic, drill hole peeping, bracket resistance and other monitoring units; acquiring surrounding rock background data before fracturing; real-time dynamic monitoring is carried out by utilizing pressure flow, reverse water and micro-shock during fracturing; carrying out static comparison and judgment by utilizing transient electromagnetism and peeping after fracturing; and the pressure relief effect is verified through support resistance and micro-seismic data in the stoping stage. And finally, performing cross validation from the dimensions of fracturing radius, pressure relief effect and water injection effectiveness based on multi-parameter data. According to the method, double-time-period accurate monitoring during fracturing and recovery is achieved, the limitation of single-means evaluation is overcome, and the comprehensiveness and accuracy of roof fracturing effect judgment are improved.

The invention belongs to the technical field of nuclear medicine and electromagnetism crossing, and particularly relates to a rapid scanning magnet for proton beam homogenization of a boron neutron capture therapy system based on a high-current cyclotron, which comprises a magnet yoke and a magnet exciting coil, wherein the magnet yoke is made of ferrite, the height of the air gap is determined by matching according to the outer diameter of the beam vacuum tube, and the proton beam vacuum tube is a large-diameter beam channel determined by taking the inner diameter of the proton beam vacuum tube as a target to meet the requirements of proton beam scanning targeting, beam halo expansion and collimation error; the two groups of excitation coils are respectively arranged on two opposite magnetic pole surfaces in the magnetic window and are positioned on the two sides of the air gap; the proportion of the magnetic pole face width and the air gap height of the magnet yoke and the size and the space layout of the magnet exciting coil meet the condition that the integral field uniformity deviation in a good field area is smaller than 1%. The problems of high temperature rise, slow magnetic field response and integral field uniformity degradation caused by an eddy current effect of a scanning magnet under a rapid excitation condition in an existing BNCT system can be solved.

The invention discloses an anti-interference differential polarimeter, which belongs to the technical field of optical measurement instruments, organically combines magneto-optical modulation with a polarization difference method for the first time, solves the problem of weak optical rotation signal detection in an open environment, has a lower glucose solution measurement limit of 0.020 g / mL, has greatly improved anti-interference capability compared with a traditional polarimeter, and has a wide application prospect. For solutions with different concentrations, the average error is maintained at a lower level of 3.25%, not only can light source fluctuation and ambient light interference be overcome and stable measurement be realized, but also subjective judgment of human eyes can be eliminated and objective quantitative reading can be realized. According to the invention, accurate measurement of a glucose solution in a range of 0.020-0.400 g / mL can be realized, automatic data acquisition and real-time concentration display are realized, and the system integrates electromagnetism, optics and information science, can be used as an ideal platform for college physical experiment and common physical experiment teaching, and has a wide application prospect. The method can also be popularized to measurement of physical quantities such as magneto-optical Kerr effect, weak magnetic field and micro displacement, and is wide in application prospect.

The embodiment of the invention relates to a magnetic field calculation and visualization program based on MATLAB, and belongs to the technical field of electromagnetic field simulation. Programs solve the problems that a traditional magnetic field calculation process is complex and visualization is inconvenient through modular design, and a single-coil, double-coil, three-coil and solenoid rapid magnetic field simulation function is provided. According to the technical scheme, the method comprises the steps that an Option module selects the type of a magnetic field, a Parameters module inputs the position / length and current parameters of a coil, an Image module automatically generates a magnetic field distribution curve, and an Experimental module supports comparison verification of experimental data and theoretical values. A user generates an image through a 'Draw a curve' button, a 'Clear' button resets canvas, 'Draw dots' overlaps actually measured data points, one-button calculation, visualization and experimental verification of magnetic field distribution are achieved, and the method is suitable for electromagnetism teaching experiments and engineering magnetic field analysis.

The invention relates to a method for calculating a scattered field of an electrically large-size scatterer, and belongs to the field of electromagnetics, and the method comprises the steps: carrying out the discretization of the surface of a curved-surface scatterer through employing a high-order curved-edge triangular unit, and carrying out the curved-surface fitting of each curved-edge triangular region through employing a quadratic equation; constructing a local coordinate system and calculating a coordinate transformation relation; converting the three-dimensional curved surface integral into pixelated integral of a two-dimensional projection screen; calculating a local radiation field based on a physical optical method, and obtaining a global scattering field through vector field synthesis; and parallel computing optimization. According to the method, quadratic patch fitting is adopted for the complex curved surface, compared with a traditional plane triangular mesh, the mesh number is reduced by 50%-70%, and computing resource consumption is greatly reduced; the three-dimensional curved surface integral is converted into the two-dimensional plane integral through the projection of the local coordinate system, and the calculation complexity is simplified.

The application discloses a ferromagnetic material suspension locking method of a static permanent magnetic array. It relates to the technical field of mechanics and electromagnetism. The method comprises the following steps: determining the structure and size of a certain number of magnetic units and composing a ring-shaped magnetic array, the centroids of all the magnetic units are in the same plane and are uniformly distributed along the circumference; the polar directions of adjacent magnetic units are alternately directed to the center direction and the circumferential tangent direction, when a plurality of magnetic units are arranged clockwise along the ring-shaped magnetic array, each magnetic unit is counterclockwise rotated by a fixed angle in the plane of the ring-shaped magnetic array compared with the previous magnetic unit, a magnetic array of an axisymmetric composite magnetic field is formed, and a magnetic array ring with the suspension locking characteristic is obtained. The application can be used for the rapid docking between large mass bodies, for example, the application of the application to the docking of a space station can avoid complex attitude adjustment, and even if deviated, the application can be quickly locked.

The utility model discloses a random drive device, including the casing, is equipped with the installation cavity and the rolling cavity, random drive subassembly, including electromagnetic drive part, magnetic rolling part and magnetic driven part, electromagnetic drive part installs in the installation cavity, magnetic rolling part installs in the rolling cavity, and magnetic driven part is used for connecting with the object to be driven, electromagnetic drive part is used for electromagnetism drive magnetic rolling part and rolls in the rolling cavity, and the rolling of magnetic rolling part can drive magnetic driven part swing through magnetic force, to drive the object to be driven swing. Because random drive device is equipped with random drive subassembly, and electromagnetic drive part can drive magnetic rolling part rolls through the magnetic field of electromagnetism, and then can drive the object to be driven swing, and magnetic rolling part rolls in the rolling cavity, and the freedom degree of movement is high, and the randomness is high, can drive the object to be driven swing more randomly, improve the reality of flame simulation piece movement, and then improve the ornamental.

The invention belongs to the field of electromagnetism teaching, and provides a current magnetic field distribution three-dimensional display device for electromagnetism teaching, which comprises a mounting shell, a plurality of uniformly distributed display boards are movably mounted on the upper surface of the mounting shell through fasteners, and a plurality of uniformly distributed display cylinders are fixedly mounted on the upper surfaces of the display boards. A flexible magnetic wire bundle is movably installed in the display cylinder through a clamping piece, the buckling piece comprises an insertion plate fixedly installed at the lower end of the display plate, a clamping groove is formed in the side wall of the insertion plate, the insertion plate is inserted into the installation shell and slidably arranged with the installation shell, and a rotating shaft is rotationally arranged in the installation shell; according to the invention, the dense array formed by a large number of flexible magnetic wire bundles which can deflect independently is arranged, and each magnetic wire bundle automatically adjusts the direction under the action of a magnetic field after being electrified, so that the distribution of magnetic induction lines around current-carrying conductors with different shapes can be three-dimensionally and vividly simulated from a three-dimensional space; an abstract magnetic field concept is converted into a concrete and visual physical model, and the teaching demonstration effect is greatly improved.

The invention relates to the technical field of earth electromagnetism, in particular to a three-dimensional magnetotelluric inversion method based on an L1 norm and an adaptive moment estimation algorithm. Collecting magnetotelluric data of the target area as observation data; dividing the non-structural tetrahedral mesh of the target area to establish an initial resistivity model; performing forward modeling calculation according to the current resistivity model to obtain predicted electromagnetic response data of the target area; constructing an inversion objective function according to the data fitting term based on the L1 norm and the model constraint term based on the L2 norm; calculating a data fitting difference between the observation data and the predicted electromagnetic response data; if the data fitting difference does not meet the set condition, updating the current resistivity model by adopting an ADAM algorithm; and iterating in sequence until the data fitting difference meets a set condition, and outputting the resistivity model at the moment as an inversion result. According to the method, the influence of a big data fitting error in inversion can be effectively suppressed, and a higher inversion resolution is obtained.

The invention provides an electromagnetic solid-phase particle residence time distribution measuring device and measuring method, and belongs to the field of electromagnetic particle measurement. In the device, a first bearing pipeline is cylindrical and is made of a non-magnetic material, an annular electromagnet is arranged on the outer side of a storage section, a first sensor is arranged on the outer side of a first induction section, a tracer inlet is communicated with the interior of the pipe, and an electromagnetic shielding shell covers the outer side of the annular electromagnet; a second sensor is arranged on the outer side of the second induction section of the second bearing pipeline; the tracer agent has soft magnetism and has flow and mass transfer behaviors which are the same as or similar to those of solid-phase particles to be detected; in the upper computer, a direct-current excitation circuit provides or cancels electromagnetism for an annular electromagnet so as to adsorb or release a tracer agent; the oscillating circuit, the first sensor and the second sensor form oscillating electromagnetic fields respectively; the sampling circuit collects a voltage pulse counting sample from the oscillation electromagnetic field and calculates an RTD value. The RTD measurement of the solid-phase particles is perfected, and the measurement range and accuracy are improved.

The invention discloses a combined advanced detection method based on borehole transient electromagnetism and direct-current resistivity, and the method comprises the steps: laying an advanced borehole in a tunnel face in a tunneling direction, carrying out the collection of borehole transient electromagnetic data, and carrying out the inversion, and obtaining a borehole transient electromagnetic inversion result; according to an inversion result and a corresponding estimation method, calculating to obtain Gaussian variation models in three main axis directions, and expanding the Gaussian variation models to any direction; then, the Gaussian variation model in any direction is substituted into a covariance calculation formula, a covariance value between any two grid units in the area needing to be detected is obtained through calculation, and a covariance constraint matrix is assembled; and finally, introducing the matrix as a regularization item into an inversion objective function of direct-current resistivity advanced detection to realize covariance constrained direct-current resistivity inversion, so that the inversion stability and the inversion imaging precision of the direct-current resistivity advanced detection are remarkably improved, and the method is suitable for scenes such as tunnel face or coal mine underground tunneling advanced detection and the like.